The stomach is the first part of the digestive tract in the abdomen. It is located between the esophagus and small intestine. Its size varies depending on the amount of substances it contains. Its main function is to initiate the digestion of food, convert it into slurry and pass it into the small intestine.
Stomach tumors usually originate from the cells that form the gastric mucosa which is the innermost part of the stomach wall. This type of cancer is called adenocarcinomas. Other less frequent stomach tumors are those coming from the deeper layers of the gastric wall (GIST, sarcomas), from lymphatic tissue (lymphoma) and those from hormone-producing cells (carcinoid tumors).
The incidence of adenocarcinoma is increasing. The primary tumor can invade the regional lymph nodes in its early stages and as the disease progresses, infiltration of surrounding organs like the pancreas, colon, spleen or liver can be seen. In advanced stages the cells can travel through the blood forming metastases in other organs such as the lung. The involvement of the peritoneal wall is another form of the characteristic progression of stomach cancer and is one of the most important criteria of inoperability.
Gastric cancer has a geographic distribution. Incidence is higher in Asiatic countries (Japan, China, and Korea) and is generally lower in Western countries (USA, Europe).
At iTAcC we have a highly specialized medical team in the diagnosis and treatment of stomach cancer. All treatment decisions are carried out in a multidisciplinary manner. This means involving specialists in the digestive system (endoscopists), general surgeons, radiologists, pathologists, radiation oncologists, and medical oncologists. Nutritionists and physiotherapists at iTAcC provide rehabilitative support to the patient during and after treatment. All of the aforementioned provides the best guarantee in the prevention, diagnosis and treatment of disease.
The main risk factors for the development of gastric cancer are:
- Diet high in salty and smoked foods.
- Low intake of fruits and vegetables.
- Chronic inflammation of the stomach due to infection from the Helicobacter pylori (Hp).
- Pernicious anemia.
- Family history of stomach cancer.
- Substance abuse: alcohol and tobacco.
- Gastric polyps.
- Gastric resection for a gastric ulcer.
Successful prevention of gastric cancer is based on:
- Avoiding fats and smoked food in the diet.
- Increase the intake of foods that represent the Mediterranean diet, such as fruits, vegetables, etc.
- Quit smoking-
- Eliminate Helicobacter Pylori.
- Follow a regular endoscopic control in family based forms of the disease and in the presence of gastric polyps in patients undergoing a resection for a gastric ulcer.
Cancer symptoms vary depending on the area of the stomach where the lesion is located:
- Symptomology in early stage tumors is usually nonspecific and slight: indigestion, eructation and fullness after eating little.
- Other signs and symptoms such as nausea, abdominal pain, vomiting, bleeding, weight loss and fatigue may occur in more advanced forms of the disease.
The most important tests for the diagnosis of stomach cancer are:
- Upper GI endoscopy (EGD): a flexible endoscope is introduced (a thin tube inserted through the mouth) and a direct visual exploration of the first part of the digestive tract is performed. This allows for tissue sampling (biopsy) to be analyzed later. It is the most important diagnostic procedure.
- Histological examination: it defines the subtype of cancer in the tissue samples and allows molecular analyses to be performed necessary in making therapeutic decisions.
- Radiology of the gastrointestinal tract: it is a backup method which is no longer very useful in the identification of small lesions.
The spread diagnosis of a disease determines the level of involvement of the stomach wall and regional lymph nodes. The various imaging tests that are done are:
- Endoscopic ultrasound: The doctor passes a flexible endoscope through the mouth. The head of the device emits ultrasounds in order to carry out an exploration of a gastric lesion directly. The depth of the tumor invasion in the gastric wall can be determined and the condition of the lymph nodes surrounding the stomach evaluated.
- A CT is usually the first step in staging stomach cancer. It is a diagnostic technique that uses X-rays to obtain razor sharp images which are used to accurately analyze the entire thoracic and abdominal cavity. A radiopaque contrast is injected in many cases for better visualization of lesions and determining the possible involvement of the lymph nodes.
- Magnetic Resonance Imaging: This technique uses electromagnetic fields and waves for imaging. The test is used in select cases when there is a degree of uncertainty regarding other diagnostic tests.
- PET: it is a test requiring the use of a small amount of radioactive glucose in order to detect growing tumor cells anywhere in the body.
ITAcC’s medical team maintains direct contact with all the previously mentioned specialists involved in making the best therapeutic decision for the patient diagnosed with stomach cancer.
At iTAcC our main objective is performing individualized treatment with each patient in order to obtain the highest success rate.
The Japanese experience (where these cases are very common) has shown that removal of these lesions by endoscopic therapy is safe and curative in the early forms of the disease. This is when the tumor is limited to the innermost layers of the gastric wall (mucosa and submucosa) and the lymph nodes have not been affected.
The surgical technique in invasive carcinomas varies with the spread and location of the tumor. It can be done by elimination of 2/3 of the stomach (partial gastrectomy) or its complete removal (total gastrectomy).
An integral part of the surgical treatment is the removal of regional lymph nodes that may be affected in a high percentage of cases even in the initial phase.
The removed tissue is examined by the pathologist who performs a histological examination. This allows accurate assessment of the spread of the tumor in the body and in the regional lymph nodes, as well as its biological aggressiveness.
Surgery can be performed in select cases via a laparoscopic approach. The surgeon performs the same surgical procedures through a small cannula introduced into the abdomen through slight incisions. This method obtains the same results compared with traditional techniques in selected patients, proportioning a faster recovery and a significant reduction in complications. Tt has become a standard today in Eastern Asian countries (Japan, Korea and China) where early-stage disease is much more common than in Europe.
Radiation therapy is administered mainly in the event of remnant cancer cells after surgery.
Radiation therapy is used in some cases as a preventive treatment following surgery when risk factors for tumor recurrence have been identified. The same goes for chemotherapy. iTAcC physicians may recommend radiation therapy in combination with chemotherapy. This depends on the clinical and pathological tumor stage as defined by the size of the lesion and the involvement of regional lymph nodes.
iTAcC has the most advanced technology for precise radiotherapy treatments. With TrueBeam STx © we can administer radiotherapy based on techniques such as volumetric modulated arc therapy (VMAT) and image guided radiation therapy (IGRT). This permits administering higher doses of radiation to the tumor with sub-millimeter precision. The system is able to detect the breathing movements of the patient which allows for treating the tumor with a maximum reduction of the side effects involving peripheral organs and tissues, such as liver, pancreas, spleen, kidneys and intestines. The treatment is done outpatient and is non-invasive, painless and administered in only a few sessions.
Chemotherapy before surgery (neoadjuvant) may reduce tumor size and increase the chances of complete removal in locally advanced tumors that cannot be completely removed. On occasion it can be administered together with radiation therapy.
Chemotherapy is used as a preventive treatment after surgery when the histological examination identifies risk factors for the recurrence of a tumor.
Chemotherapy is the primary treatment for tumors with distant metastases.
- Stenting: when the cancer is inoperable and causes blockage of the stomach or duodenum, prosthesis (stent) can be inserted improving the passage of food. This procedure is performed endoscopically and its main objective is to obtain a significant improvement of symptoms.
- Cirugía: performing a palliative surgical procedure may be proposed (individually and always after a multidisciplinary evaluation) in the case of stenosis (narrowing) when the patient cannot be treated endoscopically or in the presence of major bleeding of a tumor. This procedure involves removing part of the stomach and connecting it to the remaining part of the stomach with the small intestine (gastro-jejunal bypass).
iTAcC encourages a strong interest in research within the context of exhaustive clinical protocols. This permits the discovery of new therapies and improves existing ones, increase the survival rate and improve the quality of life of patients diagnosed with stomach cancer.
The monitoring protocol needs to begin after treatment and is based on a thorough progress control by specific imaging tests.
Follow up is done as in all oncological activity at iTAcC, in a personalized manner with cooperation of doctors who have been involved in the diagnosis and treatment of each case. iTAcC is an open institution and works closely them.