Medical

Stomach Cancer: Everything about the causes, symptoms, diagnosis and treatment of gastric cancer

Gastric cancer, one of the leading causes of cancer death, has no apparent symptoms in the early stages of the disease. How much do you know about this hidden disease?

Cancer begins when the growth of some cells in the body gets out of control. Almost all cells in the body can become cancerous and spread to other parts of the body. Gastric cancer starts in the stomach. It is not wrong to first know a little about the stomach’s standard structure and function to understand gastric cancer.

Stomach structure

The food enters the esophagus after being chewed and swallowed. The esophagus is the tube that carries food to the stomach. The esophagus joins the stomach at the junction of the esophagus with the stomach. The stomach is a sac-like organ that holds food and helps digest it by secreting gastric juice. In the stomach, food is mixed with gastric juice and then enters the first part of the small intestine called the duodenum. The stomach is made up of five parts:

  • Stomach: The first part of the stomach that is closest to the esophagus.
  • Stomach arch: The upper part of the stomach that is located near the mouth of the stomach.
  • Gastric body: The central part of the stomach that is located between the upper and lower parts
  • Antrum: The lower part of the stomach (near the small intestine) where food mixes with gastric juice.
  • Gastric pylorus: The last part of the stomach acts as a valve to control the stomach contents emptying into the small intestine.

The first three parts of the stomach (mouth, arch, and body of the stomach) are sometimes called the “close stomach.” Some cells in this part of the stomach produce acid and pepsin (a digestive enzyme) that help digest food. They also produce a protein called an endogenous factor, which the body needs to absorb vitamin B12. The lower two parts of the stomach (antrum and pylorus) are called the “distant stomach.” Other organs near the stomach include the large intestine, liver, spleen, small intestine, and pancreas. The stomach wall is made up of five layers:

The innermost layer is called the mucosal layer, where digestive enzymes and stomach acid are made. Most stomach cancers start in this layer. The next layer is the layer under the mucosa. Outside of this layer, there is a layer of muscle lining (muscle), a thick layer consisting of muscles that mix the stomach contents with their movements. The two outer layers, the serous layer, and the outer serous layer cover the stomach.

Layers are essential in determining the stage of cancer progression and determining a person’s prognosis. As cancer penetrates from the mucosal layer to the innermost layers, cancer has progressed, and the prognosis is not very good.

Progression of gastric cancer

Gastric cancer usually develops slowly over several years. Before real cancer develops, a series of precancerous changes often occur in the lining of the stomach. These early changes rarely cause symptoms and therefore are often undiagnosed. Cancers that start in different parts of the stomach can cause different symptoms and have different consequences.

Types of stomach cancers

Adenocarcinoma: About 95-90% of gastric cancers are adenocarcinomas. This type of cancer often begins in the stomach’s innermost layer, the lining of the mucosa.

Lymphoma: Lymphoma is a cancer of the immune system that sometimes occurs in the stomach wall. The treatment and outcome of this cancer depend on the type of lymphoma.

A gastrointestinal stromal tumor (GIST): These are tumors that start in very early forms of cells in the stomach wall called interstitial cells called cache. Some of these tumors are non-cancerous, while others are cancerous. However, these cancers can occur anywhere else in the gastrointestinal tract; But they are often found in the stomach.

Herpes tumors: These tumors start in the stomach’s hormone-producing cells. Most of these tumors do not spread to other organs.

Risk factors for gastric cancer

A risk factor is anything that increases a person’s chances of developing a disease such as cancer. Different cancers have different risk factors. Some risk factors, such as smoking, can be changed, while others, such as age or family history, cannot be changed. However, having one or more risk factors does not necessarily mean that the person will develop the disease. Many people who get a disease may have little or no risk factors for the disease. Several risk factors increase a person’s risk of stomach cancer, including:

Gender: The prevalence of gastric cancer is higher among men than women.

Age: The risk of stomach cancer increases with age.

Helicobacter pylori infection: Helicobacter pylori infection seems to be a major cause of stomach cancer, especially cancers in the lower stomach. Prolonged infection of the stomach with this microbe may lead to inflammation and precancerous changes in the stomach’s inner layer. People with gastric cancer have a higher rate of infection with the bacterium than people without cancer. Helicobacter pylori infection is also associated with several types of gastric lymphoma. However, most people who have this germ in their stomach never get cancer.

Gastric lymphoma: People with a particular type of gastric lymphoma called gastric mucosal lymph node cancer (MALT) are at risk for adenocarcinoma. This is because the infection causes MALT gastric lymphoma with Helicobacter pylori.

Diet: People with diets rich in smoked foods, salty meats, and pickled vegetables are at higher risk for stomach cancer. Nitrates and nitrites commonly found in processed meats can be converted by certain bacteria, such as Helicobacter pylori, to compounds that cause stomach cancer in laboratory animals. Consuming large amounts of fresh fruits and vegetables seems to reduce the risk of stomach cancer.

Tobacco use: Smoking increases stomach cancer risk, especially cancers in the upper stomach and near the esophagus. The prevalence of gastric cancer in smokers is almost twice that of non-smokers.

History of gastric surgery: People who have undergone surgery to treat non-cancerous diseases such as gastric ulcers and have had part of their stomach removed are more likely to develop gastric cancer. This may be because the stomach produces less acid and the nitrite-producing bacteria have a chance to grow. The return of bile from the small intestine into the stomach after surgery also increases the risk. These cancers usually occur years after surgery.

Pernicious anemia: Certain cells in the stomach wall make the protein, the internal factor we need to absorb vitamin B12. People who do not have enough of this internal factor may eventually become deficient in vitamin B12, which affects the ability to make new red blood cells and cause other problems. This condition is known as pernicious anemia. In addition to anemia, people with the disease are at higher risk for stomach cancer.

Menteri disease (hypertrophic gastropathy): In this condition, the gastric lining’s overgrowth causes large folds in the stomach and decreases stomach acid levels. Because the disease is so rare, it is unclear exactly how much it increases stomach cancer risk.

Blood type A: For unknown reasons, people with blood type A are at higher risk for stomach cancer.

Hereditary Cancer Syndromes: Some inherited conditions may increase a person’s risk of stomach cancer, including:

Hereditary disseminated gastric cancer: This inherited syndrome significantly increases the risk of developing gastric cancer. It is rare, but stomach cancer risk among these people is about 80-70%. Women with this complication are also at higher risk for certain types of breast cancer. A mutation in the CDH1 gene causes the disease.

Lynch Syndrome: Lynch Syndrome, formerly known as HNPCC, is an inherited genetic disorder that increases the risk of colon cancer, stomach cancer, and some other cancers. In most cases, this disorder is caused by a defect in the MLH1 or MSH2 genes, but other genes can also cause Lynch syndromes, such as the MLH3, MSH6, TGFBR2, PMS1, and PMS2 genes.

Familial adenomatous polyposis: Many polyps form in the large intestine and sometimes the stomach and small intestine of people with this disease. People with this syndrome are at increased risk for colon cancer and have a slightly increased risk of stomach cancer. Mutations in the APC gene cause this syndrome.

BRCA1 and BRCA2 genes: People who have mutations in the breast cancer genes BRCA1 and BRCA2 may also be at higher risk for stomach cancer.

Lee-Framani Syndrome: People with this syndrome have a higher risk of developing several cancer types, including stomach cancer. A mutation in the TP53 gene causes Lee-Fraumeni syndrome.

Putz Jagger Syndrome: Polyps form in the stomach and small intestine and other parts of the body such as the nose, airways, lungs, and bladder of people with the syndrome. The gastric and intestinal polyps of these patients are of a particular type called hamartoma. They can cause problems such as bleeding or small bowel obstruction. Potts-Jagger syndrome can also cause dark spots on the lips or inside the lips. People with this syndrome are also at risk for cancers of the breast, colon, pancreas, stomach, and other organs. A mutation in the STK1 gene causes this syndrome.

Family history of gastric cancer: People with first-degree relatives with gastric cancer are more likely to develop it.

Some types of gastric polyps: Polyps are non-cancerous growths that form on the lining of the stomach. Many of these polyps do not appear to increase a person’s risk of stomach cancer, but ADS polyps can sometimes turn into cancer.

Epstein-Barr virus infection: Epstein-Barr virus causes infectious mononucleosis. Almost all adults get the infection at some point in their lives. Epstein-Barr virus has been linked to some forms of lymphoma. The virus is also found in cancer cells in about 5-10% of people with gastric cancer. Cancer in these people has slower growth and a less invasive state, and its spread is slower. Epstein-Barr virus has been found in some gastric cancer cells, But it is unclear whether it causes stomach cancer.

Unique Occupations: Workers in industries such as coal, metal, and rubber appear to be at higher risk for gastric cancer.

Common variable immunodeficiency: People with common variable immunodeficiency are at higher risk for gastric cancer. The immune system of a person with the disease cannot produce enough antibodies in response to the presence of germs. Affected people frequently develop infections and other problems such as atrophic gastritis and pernicious anemia. They are also more likely to develop gastritis, lymphoma, and stomach cancer.

What causes stomach cancer?

There are several known risk factors for stomach cancer, But it is unclear how they cause stomach cells to become cancerous. Several changes that are thought to be precancerous conditions may occur in the lining of the stomach, some of which are noted:

In chronic atrophic gastritis, the normal glands of the stomach are weakened or absent. There is also some degree of inflammation, meaning that stomach cells are damaged by immune system cells. Atrophic gastritis is often caused by Helicobacter pylori infection. This condition can also be caused by an autoimmune reaction in which a person’s immune system attacks the stomach’s lining cells. Some people with this condition go on to develop pernicious anemia or other stomach problems such as cancer.

Another possible precancerous change is intestinal metaplasia. In this condition, cells similar to the gut’s lining cells replaced the stomach’s standard lining. People with this disease usually also have chronic atrophic gastritis. How and why this change occurs and progresses to gastric cancer is not well understood. This may be related to Helicobacter pylori infection.

Recent research has provided evidence of how gastric cancer develops. For example, Helicobacter pylori, especially certain strains of it, can convert substances in some foods into chemicals that cause mutations in the DNA of the cells lining the stomach. This explains why certain foods, such as processed meats, increase the risk of stomach cancer. On the other hand, some foods that may reduce stomach cancer risks, such as fruits and vegetables, contain antioxidants that can inhibit DNA-damaging substances.

Scientists have made great strides in understanding how specific DNA changes can cause normal stomach cells to grow abnormally and lead to cancer. Some genes control the time it takes for cells to grow and divide:

  • The genes that help cells grow and divide are called oncogenes.
  • Genes that control cell division or cause a cell to die at the right time are called tumor suppressor genes.

Changes in DNA that turn oncogenes on or turn off tumor suppressor genes can cause cancer.

Inherited mutations in some genes can increase a person’s risk of stomach cancer. Mutations are thought to be the cause of only a small percentage of stomach cancers. However, genetic tests can be done to identify gene mutations that can cause some inherited cancer syndromes. Most of the genetic changes that lead to stomach cancer occur after birth. Some of these changes may be due to risk factors such as Helicobacter pylori infection or tobacco use. But other genetic changes maybe just a random event that sometimes happens inside the cells for no apparent reason.

Is stomach cancer preventable?

There is no safe way to prevent stomach cancer, but something can be done to reduce the risk.

Diet, body weight, and physical activity: The dramatic decline in gastric cancer incidence in recent decades is thought to be because people have eliminated many of the risk factors associated with diet. These include using the refrigerator to store food instead of salting, pickling, and smoking. To help reduce your risk of stomach cancer, you should avoid diets that are high in smoked foods, pickles, and salty meats and fish. A diet high in fresh fruits and vegetables can reduce the risk of stomach cancer.

The American Cancer Society recommends a healthy diet with an emphasis on plant-based foods. This recommendation includes eating at least two and a half cups of vegetables and fruits each day. Choosing whole-grain bread and foods instead of refined grains and eating fish, poultry, and beans instead of red meats and processed meats may also help reduce cancer risk.

Avoid smoking: Smoking increases the risk of stomach cancer near the esophagus. Tobacco use also increases the risk of other cancers.

Treatment of Helicobacter pylori infection: It is not yet clear whether people whose gastric lining is chronically affected by Helicobacter pylori infection but have no symptoms should be treated with antibiotics. Some early studies have shown that giving antibiotics to people with Helicobacter pylori infection may reduce the number of precancerous lesions in their stomach and reduce stomach cancer risk. But not all studies have shown this relationship. There are several ways to check for an infection in a person’s stomach:

  1. The easiest way is to have a blood test that looks for Helicobacter pylori antibodies in the blood. Antibodies are proteins that the immune system produces in response to infection. If the antibody test is positive, it indicates that either the person is infected with the bacterium or has had the infection before but has now cleared up.
  2. Another method is to perform an endoscopy to take a sample of stomach cells. A series of chemical tests are performed on the sample. The bacterium can also be detected in a sample using a microscope. The sample can also be cultured to see if the bacterium is produced by culturing the sample.
  3. There are also specific respiratory tests to detect this bacterium. To do this, the patient drinks a liquid containing urea. If the desired bacteria is present, the area undergoes a chemical change (urea breath test).

Aspirin: The use of aspirin or other nonsteroidal anti-inflammatory drugs (NSAIDs) such as ibuprofen or naproxen appears to reduce the risk of stomach cancer. These drugs can also reduce the risk of developing colon polyps and colon cancer. But at the same time, these drugs can cause internal bleeding and other problems in some people. Doctors do not recommend the use of NSAIDs to prevent stomach cancer.

People at high risk for stomach cancer

The cause of a small percentage of gastric cancers is diffuse inherited gastric cancer syndrome. Still, it is essential to be diagnosed because most people with this condition will eventually develop gastric cancer.

Having a personal history of invasive lobular breast cancer before age 50 and having a family member with gastric cancer suggests that the person may also have the syndrome. These people can have a genetic test. If the test results show that a person has a mutation in the CDH1 gene, many doctors recommend that your stomach be removed before cancer develops. Another inherited cancer syndrome that is associated with an increased risk of gastric cancer is Lynch syndrome.

Is gastric cancer detectable in the early stages?

Screening is a test to look for a disease such as cancer in people who have no symptoms. In countries like Japan, where stomach cancer is prevalent, screening can detect many disease cases in the early and treatable stages. Still, in countries where gastric cancer is not widely screened, most people have the disease until the symptoms. To the extent that they require a medical examination, they are not identified.

Signs and symptoms of stomach cancer

Gastric cancer rarely causes symptoms in the early stages, making it challenging to diagnose stomach cancer in the early stages. Signs and symptoms of gastric cancer may include the following:

  • Poor appetite
  • Weight Loss
  • Pain in the abdomen, especially in the upper umbilicus
  • Feeling full in the upper abdomen after a short meal
  • Heartburn or indigestion
  • nausea
  • Vomiting with or without blood
  • Swelling or accumulation of fluid in the abdomen
  • The presence of blood in the stool
  • Reduce the number of red blood cells

Most of these symptoms may be caused by factors other than cancer, such as stomach viruses or stomach ulcers. These symptoms may also occur in other cancers, but people who have any of these problems, especially if their symptoms do not go away or worsen, need to see a doctor for a diagnosis.

Tests related to the diagnosis of gastric cancer

Gastric cancer is usually diagnosed when a person sees a doctor because of the symptoms. The doctor will ask about the patient’s medical history and examine him or her. If she is suspected of having stomach cancer, tests should be done to confirm or rule out the diagnosis.

Medical history and physical examination: The physician asks the patient questions about symptoms such as eating problems, pain, bloating, and related risk factors. The physical exam will give the doctor information about your general health status, possible signs of stomach cancer, and other health problems. Your doctor will check for any unusual changes in the patient’s abdomen. If your doctor suspects that you may have stomach cancer or other stomach problems, he or she will refer you to a gastroenterologist for further tests.

Upper endoscopy: Upper endoscopy or EGD is the primary test for diagnosing stomach cancer. In this test, a doctor inserts an endoscope, a thin tube with a light source and a small video camera, through the patient’s stomach through the throat. This allows the doctor to see the lining of the esophagus, stomach, and small intestine. If abnormal areas are observed, sampling is performed using an instrument attached to an endoscope. The samples are sent to a laboratory and used a microscope to determine if cancer cells are present. Gastric cancer can look like a bulging or fungal mass, thickened, flat, and scattered mucus areas known as lignite plastic. Hereditary disseminated gastric cancer syndrome is often not visible through endoscopy.

Endoscopic ultrasound: Ultrasound uses sound waves to produce images of organs such as the stomach. During a standard ultrasound, a swab-like instrument called a transducer is placed on the skin. This device generates sound waves and then detects the return waves from the internal organs. A computer processes these echoes’ pattern and a black and white image are displayed on the screen. In endoscopic ultrasound (EUS), a small transducer is placed at the end of the endoscope. After the patient is ready, the endoscope is passed through his throat and reaches his stomach. By doing this, the transducer can be placed on the stomach wall, where cancer can be present. Doctors can examine the stomach and lymph nodes’ layers and other structures near the stomach. This image’s quality is better than that of a standard ultrasound due to the shorter distance the sound waves travel. The main advantage of the EUS method is that it observes the spread of cancer in the stomach wall, adjacent tissues, and lymph nodes. This procedure can also be used to guide a biopsy needle (sampling).

Biopsy: If an abnormal area in the stomach is seen through endoscopy or imaging, your doctor may suspect cancer, but the only way to make a definitive diagnosis is to take a biopsy. In practice, the doctor takes a sample of abnormal area cells. Samples taken to check for stomach cancer are often taken during upper gastric endoscopy. If the doctor sees any abnormal areas in the stomach lining during the endoscopy, they will insert the sampling tool into the stomach through the endoscope. Some types of stomach cancers can develop deep in the stomach wall, making them difficult to sample using standard endoscopy. If your doctor suspects that cancer may have occurred deep in the stomach wall, he or she can use endoscopic ultrasound to guide the sampling needle into the stomach wall. Sampling may also be done from cancer areas that have spread, such as nearby lymph nodes or suspicious areas in other parts of the body.

Test biopsy specimens

Biopsy specimens are sent to a laboratory under a microscope to examine cancer and the type of cancer. If the sample contains cancer cells, more tests may be done. For example, a tumor may be examined to see if it has high levels of a growth-promoting protein called HER2. Tumors in which HER2 levels are high are called HER2 positive. HER2-positive gastric cancers can be treated with drugs that target the HER2 protein. There are two different ways to look at a biopsy specimen:

  1. Immunohistochemistry (IHC): In this test, specific antibodies bind to the HER2 protein are added to the sample. If a large amount of this protein is present, the cells’ color will change. The color change is examined under a microscope. The results of this test are reported as 0, +1, +2, or +3.
  2. In-situ hybridization (FISH): This test uses fluorescently labeled DNA fragments that bind specifically to copies of the HER2 gene in cells and can be counted using a special microscope.

The IHC test is usually done first. If the result is 0 or +1, HER2 cancer is negative. People with HER2-negative tumors are not treated with drugs that target HER2. If the test result is +3, it is HER2 positive. Patients with HER2-positive tumors may be treated with drugs such as trastuzumab. When the test result is +2, the HER2 status of the tumor is unknown. This often leads to tumor testing using the FISH technique.

In another test, the tumor may be tested for a certain amount of a specific immune-checking protein called PD-L1. If so, the tumor may be treated with a protein inhibitor such as pembrolizumab.

Imaging experiments

Imaging experiments use X-rays, magnetic fields, sound waves, or radioactive materials to create images of the body’s inside. Imaging tests may be performed for several reasons:

  • To diagnose cancer as a suspicious area.
  • To observe the spread of cancer.
  • To help determine the effectiveness of treatment.

GI Imaging Tests: This x-ray exam examines the lining of the esophagus, stomach, and early small intestine. This method is less commonly used to diagnose stomach cancer or other stomach problems than endoscopy. It may not show some abnormal areas and may not allow doctors to take tissue samples. However, this method is less invasive than endoscopy and can be useful in some situations.

To perform this test, the patient drinks a white plaster-like solution containing barium. Barium sits on the lining of the esophagus, stomach, and small intestine. Several x-ray images are then taken. Because X-rays cannot pass through the barium, these images can show abnormalities in these organs’ lining. The double contrast technique is also used to diagnose early-stage gastric cancer. In this method, after the patient eats the barium solution, a thin tube is inserted into his stomach through which air is pumped into the stomach. This leads to a thinning of the barium layer, and even small abnormalities will appear.

Computed tomography: A CT scan uses X-rays to create accurate, cross-sectional images of the body. CT scans often produce relatively clear images and shows the location of cancer. CT scans also show nearby organs in the stomach, such as the liver and lymph nodes, and more distant organs that cancer may have spread to. A CT scan can help determine the stage of cancer and whether surgery is a good option for that person.

CT scan-guided biopsy: CT scan is also used to guide the biopsy needle into the suspected area of ​​cancer spread. The patient is placed on a CT scan, and the doctor guides the biopsy needle toward the mass. CT scans are repeated until the needle reaches the mass. A small sample is taken and examined under a microscope.

MRI Scan: Like CT scans, MRI scans provide an accurate picture of the body’s soft tissues. But MRI scans use radio waves and a strong magnetic field instead of X-rays.

PET Scan: a radioactive substance is first injected into a person. This substance will mainly accumulate in cancer cells. Next, a special camera is used to create an image of the radioactive areas in the body. This image is not an accurate CT scan or MRI scan but can look for areas where cancer may have spread.

Chest X-ray: This test is helpful when cancer is likely to spread to the lungs. Of course, this test is not necessary if a chest scan has been performed.

Laparoscopy: This procedure is usually used when stomach cancer has been diagnosed. Although CT scans or MRIs can show accurate images of the body’s inside, they may not show tiny tumors. Doctors may perform a laparoscopy before surgery to confirm cancer in the stomach and whether it can be removed. The operation is performed in an operating room under general anesthesia. A laparoscope (a thin, flexible tube) is inserted through a small hole in the patient’s side. The laparoscope has a small video camera at the end that sends images of the abdomen to a screen.

Using this method, doctors can take a closer look at adjacent organs and lymph nodes’ surfaces or even take small samples. If cancer has not spread, doctors sometimes wash the abdomen with saline solution. The fluid is then removed and examined for the possible presence of cancer cells. If so, it means that cancer has spread even if its spread is not noticeable. Sometimes laparoscopy is combined with ultrasound to get a better picture of cancer.

Laboratory tests: Doctors may order a blood cell count test when looking for stomach cancer signs to determine if there is anemia (which could be due to bleeding from cancer). An occult blood test may also be done to determine if the stool’s blood is not visible.

Your doctor may order other tests if you are diagnosed with cancer, especially if you have surgery. For example, a series of blood tests are performed to ensure normal kidney and liver function and normal blood clotting. If surgery is to be performed or the person is taking medications that affect their heart, an electrocardiogram and an echocardiogram may also be done to check heart function.

Stages of gastric cancer

After the presence of gastric cancer is confirmed, doctors examine the condition of cancer in terms of spread and extent of spread. Determining the stage of cancer describes the state of cancer in the body. This helps determine the severity of cancer and the best treatment. The initial stage of gastric cancer is called stage zero and then enters stages one to four. As a rule, the lower the number, the lower the spread of cancer. A higher number, like stage four, indicates the widespread spread of cancer. Although each person’s experience with cancer is unique, cancers have the same outlook at the same stage and are often treated in the same way.

The stage detection system used for gastric cancer is the TNM system, which is based on three sets of essential information:

Tumor size (T): To what extent has cancer grown in the five layers of the stomach wall? Has cancer spread to nearby structures or organs?

The spread of cancer to adjacent lymph nodes (N): Has cancer spread to adjacent lymph nodes?

The spread of cancer to distant parts (M): Has cancer spread to more distant lymph nodes or organs such as the liver or lungs?

The numbers or letters that come after T, N, and M provide more detail about these properties. Larger numbers mean there has been more cancer progression. Once a person’s gastric cancer classification is determined in T, N, and M, this information is combined in a process called stage grouping to determine a general stage for the disease.

Treatment of gastric cancer

When a person is diagnosed with gastric cancer, the medical team will discuss the treatment options available and discuss each method’s pros and cons.

Gastric cancer surgery

Surgery is part of the treatment for many stages of gastric cancer if the person has the condition. If the disease is in stages zero, one, two, or three, and the patient is healthy enough, surgery (often with other treatments) will be the only real chance of cure in these stages. Surgery may be performed to remove cancer and part or all of the stomach and some surrounding lymph nodes, depending on the stomach cancer type and stage. The surgeon will try to leave as many healthy parts of the stomach as possible. Sometimes some other organs need to be removed.

Various surgeries are used to treat stomach cancer.

Endoscopic incision

Surgical procedures for endoscopic incision of the mucosa and endoscopic incision under the mucosa are used only to treat some cancers in the very early stages. The risk of cancer spreading to the lymph nodes is shallow. These processes do not need to create a gap in the skin. Instead, the surgeon inserts an endoscope through the throat into the stomach. The surgical instrument is inserted through the endoscope into the stomach and tumor, and part of the surrounding healthy wall is removed.

Partial gastric surgery

This procedure is often recommended if the cancer is only in the lower part of the stomach. This method is less commonly used for cancers that occur only in the upper part of the stomach. Only part of the stomach is removed, sometimes with the esophagus or the small intestine’s initial part (duodenum). The rest of the stomach is then reconnected. Part of the omentum (a layer of fatty tissue covering the stomach and small intestine) also separates with adjacent lymph nodes and possibly the spleen and parts of other adjacent organs.

General gastric surgery

This is done if cancer has spread throughout the stomach. It is also often recommended if cancer has occurred in the upper stomach near the esophagus. The surgeon removes the entire stomach, adjacent lymph nodes, and odontoma. The spleen and parts of the esophagus, small intestine, pancreas, or other nearby organs may also be removed. The end of the esophagus then connects to the small intestine. This allows food to enter the small intestine from the esophagus.

Most general and minor gastric surgeries are performed by making a large incision in the abdomen’s skin. This operation is performed using laparoscopy in some medical centers.

Lymph node resection

In total or partial gastric surgery, adjacent lymph nodes are also removed. This is an essential part of the action. Many physicians believe that the success of this procedure depends directly on how many lymph nodes are removed. It is recommended that at least 15 lymph nodes be removed in the United States during this type of gastric surgery. Japanese surgeons are very successful in this area and remove many lymph nodes near cancer.

Soothing surgery

For people whose stomach cancer cannot be removed even with surgery, surgery can prevent or alleviate symptoms or side effects. Removing a portion of the stomach with a tumor can help treat bleeding, pain, or obstruction of the stomach, even if it does not cure cancer. Because this type of surgery aims not to treat cancer, there is no need to remove nearby lymph nodes and other limbs.

Gastric bypass

Tumors in the lower part of the stomach may eventually become large enough to prevent food from leaving the stomach. One option to solve this problem is to leave the lower part of the stomach aside. This is done by attaching part of the small intestine to the upper part of the stomach. This removes food from the stomach in a new way.

Tumor destruction with endoscopy

In some cases, such as in people who do not have the necessary health conditions for surgery, an endoscope can be used to guide the laser beam and evaporate parts of the tumor. This is useful to prevent bleeding or blockage without the need for surgery.

Stenting

Another option to prevent tumor obstruction by the tumor is to use an endoscope to place a stent (a hollow metal tube) at the stomach’s entrance into the intestine. This keeps the path open and allows food to pass through. For tumors in the stomach’s upper part, this stent is placed at the esophagus and stomach junction. For tumors in the lower stomach, the stent is placed at the stomach and small intestine junction.

Insert the feed tube:

Some people with gastric cancer may not be able to eat enough. In this position, a small operation is performed to insert a tube of food through the abdomen’s skin into the area around the stomach or small intestine. Soluble nutrients can then enter the tube directly.

Side effects and possible problems caused by gastric surgery

Surgery is difficult to treat gastric cancer and can cause bleeding from a surgery, blood clots, and nearby organs’ damage during surgery. Rarely, new connections are made between the end of the stomach or esophagus and the small intestine, which may leak. Surgical techniques have advanced dramatically in recent years, with only about 1-2% of people dying from gastric surgery. This number is higher in cases where the operation becomes more complicated, such as when all the lymph nodes have been removed and a decrease in cases performed by experienced surgeons.

The patient will not be allowed to consume food or water for a few days after full or partial gastric surgery. This improves the gastrointestinal tract and ensures no leaks in the surgeon sutured sections during the operation. The patient may experience complications such as nausea, heartburn, abdominal pain, and diarrhea after recovery from surgery, especially after eating. These side effects are because part or all of the stomach is removed, and food enters the small intestine quickly. These side effects often get better over time, but they may persist for a long time in some people.

Therefore, general or partial gastric surgery is necessary to change the diet, and the most significant change is that the patient should eat more often and in smaller amounts. The volume of the stomach removed determines how much the sick person can eat. The stomach helps absorb some vitamins, so people who have gastric bypass surgery may be deficient in vitamins. If certain parts of the stomach are removed, doctors prescribe vitamin supplements, some of which only need to be injected.

Before the operation, the patient should ask the doctor how much his stomach is removed. Some surgeons try to keep healthy parts of the stomach as long as possible so that the patient can generally eat afterward. The problem with this is that there is a possibility of cancer recurrence. It is emphasized once again that the surgeon must have sufficient experience to perform this operation.

Chemotherapy for the treatment of gastric cancer

In chemotherapy, injectable or oral anticancer drugs are used. These drugs enter the bloodstream and reach all parts of the body. This treatment is useful for cancers that have spread to different parts of the body. Chemotherapy can be used to treat stomach cancer in several ways:

These drugs can be taken before gastric cancer surgery. This can make the tumor smaller and make surgery easier. It can also prevent cancer from coming back and help the patient survive longer. For some stages of stomach cancer, this method is one of the standard treatment options. The patient will often take these medications after surgery.

Chemotherapy may be given only after surgery to remove cancer. The purpose of this procedure is to kill cancer cells that may have survived the operation. This prevents cancer from coming back. For gastric cancer, chemotherapy is often given along with radiation therapy after surgery. This combination method is beneficial for cancers that cannot be entirely removed by surgery.

Chemotherapy may be the first treatment option for gastric cancer that has spread to the body’s distant areas. This procedure may help reduce the size or growth of cancerous tumors, but it may also improve some patients’ symptoms and help them survive longer.

Chemotherapy drugs are taken periodically. After each treatment period, there is a period of rest, an opportunity for the body to regenerate. Each course of treatment usually lasts several weeks. Some of the essential chemotherapy drugs used to treat stomach cancer are:

  • 5-FU, which is often prescribed with leucovorin
  • Capecitabine
  • Carboplatin
  • Cisplatin
  • Docetaxel
  • Epirubicin
  • Irinotecan
  • Oxaliplatin
  • Paclitaxel

Depending on the condition (stage of cancer, the individual’s general health, and whether chemotherapy is given in combination with radiation therapy), these drugs can be used alone or other chemotherapeutic drugs or targeted drugs.

Side effects of chemotherapy

Chemotherapy drugs attack cells that are rapidly dividing. But some of the body’s cells, such as those found in the bone marrow, the lining of the mouth and small intestine, and the hair follicles, divide rapidly. These cells may also be affected by these drugs, which can lead to side effects. The type of side effects depends on the type of medication, the amount is taken, and the duration of treatment. Common short-term side effects of most chemotherapy drugs can include the following:

  • Nausea and vomiting
  • Loss of appetite
  • hair loss
  • Diarrhea
  • Oral ulcers
  • Increased risk of infection
  • Bleeding or bruising after minor injuries
  • Fatigue and shortness of breath

These side effects are often short-lived and go away when the treatment is over. For example, after the end of the treatment, hair growth starts again. But the patient should talk to the doctor about the side effects of these drugs; there are ways to reduce these effects. Some chemotherapeutic drugs have specific side effects:

Neuropathy: Cisplatin, oxaliplatin, docetaxel, and paclitaxel can damage nerves outside the brain and spinal cord. This can sometimes lead to symptoms (mostly in the arms and legs) such as pain, burning or tingling sensation, sensitivity to cold or heat, or weakness. In most cases, these symptoms disappear when treatment is stopped, but these effects may be more lasting in some patients. Oxaliplatin can also affect the throat’s nerves and cause a sore throat, worsening when eating or drinking cold foods or liquids. This pain can lead to swallowing and even breathing problems and may continue for several days after treatment.

Heart damage: Doxorubicin, epirubicin, and some other medications can cause permanent damage to the heart if used for long periods or in high doses. Thus, doctors carefully monitor these drugs’ doses and use heart tests to monitor the patient’s heart function. Treatment with these drugs should be stopped as soon as the first sign of heart damage is seen.

Hand and foot syndrome may occur during treatment with capsaicin or 5-FU. These symptoms begin with redness of the hands and feet and can lead to pain and tenderness in the hands and feet’ palms. The skin may become blistered and scaly, and sometimes painful open sores develop. These symptoms gradually improve with stopping the medication or reducing the amount of medication taken. The best way to prevent severe hand and foot syndrome is to tell your doctor when the first symptoms start to change the amount of medicine.

Targeted therapies for gastric cancer

Targeted drugs may be helpful in some cases where standard chemotherapy drugs do not work. The side effects of these drugs are different from the side effects of chemotherapy drugs. Chemotherapy drugs target cells that are rapidly dividing. But cancer cells differ from normal cells in other aspects besides rapid cell division. In recent years, researchers have developed new drugs to target these differences:

Trastuzumab: About 20% of stomach cancer cases have a large amount of a growth-promoting protein called HER2 on the surface of cancer cells. Tumors that have high levels of HER2 are called HER2 positive.

Trastuzumab is a monoclonal antibody; A synthetic version of a particular immune protein that targets the HER2 protein. Co-administration of trastuzumab with chemotherapy drugs can help some patients with advanced HER2-positive gastric cancer survive longer.

It only works if the cancer cells have large amounts of HER2, so a tumor sample should be tested before starting this treatment. This method is not used for people whose cancer is HER2 negative.

Side effects of trastuzumab are relatively mild. These can include tabulations, weakness, nausea, vomiting, cough, diarrhea, and headache. These side effects are less likely to occur during the first dose. It rarely causes heart damage. The risk of heart damage increases if the drug is taken with certain chemotherapy drugs called anthracyclines (such as epirubicin or doxorubicin).

Ramosiromab: For cancer to grow and spread, it needs to create new blood vessels through which tumors can receive blood and nutrients. One of the proteins that tell the body to make new blood vessels is the VEGF protein. The VEGF protein binds to cell surface proteins called cellular receptors.

Ramosiromab is a monoclonal antibody that binds to a VEGF receptor. This prevents the VEGF from connecting to its receiver. This helps prevent or reduce the growth and spread of cancer. Ramosiromab is used to treat advanced stomach cancers, often after other medications have not been affected. The most common side effects are high blood pressure, headache, and diarrhea. Rarely, complications such as blood clots, heavy bleeding, cavities in the stomach and intestines, and wound healing problems may occur. If a hole forms in the stomach or small intestine, it can lead to severe infections that may require surgery to treat.

Immunotherapy for gastric cancer:

Immunotherapy is the use of drugs that help a person’s immune system find and destroy cancer cells.

Immunosuppressants: An essential part of the immune system is its ability to protect itself from attacking the body’s natural cells. The system uses several checkpoints: molecules on immune cells that must be turned on or off to initiate an immune response. Cancer cells sometimes use these points to protect themselves from immune system attacks. But newer drugs that target these areas are an excellent place to treat cancer.

Pembrolizumab targets PD-1; A protein located on T cells, and prevents these cells typically from invading other cells in the body. By inhibiting PD-1, the drug boosts the immune response against cancer. This drug can reduce the size of some tumors or slow their growth. Possible side effects of this medicine may include:

  • Feeling tired or weak
  • Fever
  • Cough
  • nausea
  • Itching
  • Skin rash
  • Loss of appetite
  • Muscle or joint pain
  • Shortness of breath
  • Constipation or diarrhea

Occasionally there may be side effects, such as:

Injection reactions: Some people have an injection reaction when they take this medicine. This is similar to an allergic reaction and can include fever, chills, flushing, pimples, itchy skin, dizziness, wheezing, and difficulty breathing.

Autoimmune reactions: This drug works primarily by inhibiting the inhibition of the immune system. Sometimes the immune system starts to attack other parts of the body, leading to severe or even fatal problems in the lungs, small intestine, liver, hormone-producing glands, kidneys, skin, and other organs. The patient should report new side effects to their medical team immediately. If severe side effects occur, treatment may need to be stopped, and the patient is given high doses of corticosteroids to suppress the immune system.

Radiation therapy for stomach cancer

Radiation therapy uses high-energy particles or rays to kill cancer cells in a specific area of ​​the body. Radiation is used in a variety of ways to help treat stomach cancer:

Before surgery for some cancers, radiation can be used in combination with chemotherapy to reduce the tumor’s size and make surgery easier.

Postoperative radiation therapy can kill small cancerous debris that could not be seen or removed during surgery. Radiation therapy, mainly when used in combination with chemotherapy drugs such as 5-FU, may prevent or delay cancer recurrence after surgery. Radiation therapy can reduce growth and stop the symptoms of advanced stomach cancers such as pain, bleeding, and eating problems. Extracorporeal radiation therapy is also used to treat stomach cancer. In this method, with the help of a device that is placed outside the body, rays are sent to the cancerous tissue inside the body. Side effects of radiation therapy for stomach cancer can include the following:

  • Skin problems range from redness of the skin to blisters and flaking in the area where the radiation has passed. (Oily Skin And Everything You Need To Know About Caring For It)
  • Nausea and vomiting
  • Diarrhea
  • Fatigue
  • Decreased number of blood cells
  • These symptoms usually go away within a few weeks of completing the course of treatment.

Worse side effects may occur when radiation therapy is given in combination with chemotherapy. Patients may have difficulty drinking enough fluids. In some cases, it may be necessary to inject fluids or use a feeding tube to feed during the treatment period. The patient should talk to the doctor about any side effects but find a way to solve them.

Radiation therapy may also cause damage to nearby organs. This can lead to heart or lung damage problems or even increase the risk of other cancers. Doctors try to prevent this as much as possible by using the required dose of radiation, controlling the radiation’s location, and covering specific areas of the body during treatment. The treatment must be done in centers where doctors have enough experience in treating stomach cancer.

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