The Farber Center: For Radiation Oncology

Gastrointestinal Cancer: Gastric Cancer

Gastrointestinal cancer refers to malignant disease of the gastrointestinal tract. It includes cancers of the esophagus, stomach (also called gastric cancer), liver, biliary system, pancreas, colon, rectum, and anus.

The American Cancer Society's most recent estimates for stomach cancer in the United States are for 2009:
21,130 new cases of stomach cancer and 10,620 deaths from stomach cancer.
Two out of 3 people found to have stomach cancer are older than 65. The risk of a person getting stomach cancer in their lifetime is about 1 in 112. The risk is slightly higher for men than for women. Stomach cancer is much more common in other parts of the world, such as Japan, Korea, and parts of Eastern Europe and Latin America. It was once a leading cause of cancer deaths in the United States, but it is now much less common.

There are several signs and symptoms in patients found to have gastrointestinal cancer, which vary from person to person and depend on the anatomic location. Not all patients exhibit any or all symptoms, which may include:

Unintended weight loss

Lack of appetite (anorexia)

Abdominal pain

Vague discomfort in the abdomen, often above the navel

A sense of fullness just below the chest bone after eating a small meal

Heartburn, indigestion, or ulcer-type symptoms

Nausea

Vomiting, with or without blood

Swelling or fluid build-up in the abdomen

Persistent tiredness

Unexplained low blood counts

Risk Factors

Age (the risk of developing gastric cancer increases with age)

Smoking cigarettes

Chronic gastritis

Gastric polyps

Poor diet: a diet low in fruits and vegetables and high in smoked and salted foods

Family history of gastric cancer

Gender: men are more likely to develop gastric cancer

A history of stomach disease

Diagnosing Gastric (Stomach) Cancers

Upper endoscopy: is an important test for diagnosing esophageal cancer. An endoscope is a thin, flexible tube with a light and video camera on the end. The doctor uses it to look at the inside of the esophagus and the stomach. If there are any areas of concern, a small piece of tissue can be removed through the tube to see if the area is cancer (biopsy).

Upper GI (gastrointestinal) series: patients drink a chalky liquid containing barium. The barium coats the lining of the esophagus, stomach, and first part of the small intestine. Because x-rays can't pass through the coating of barium, this will outline anything that isn't normal in the lining of these organs. X-rays are then taken. Sometimes, after the barium is swallowed, a thin tube is passed into the stomach and air is pumped in. This makes the barium coating very thin so that even small areas of change will show up.

Endoscopic ultrasound (EUS): In an ultrasound, sound waves are used to make pictures of internal organs. Most people know about ultrasound because it is used to get a picture of the baby during pregnancy. Ultrasound can also be done with a probe put down the throat into the stomach. It can help tell how far the cancer has spread within the stomach or into nearby tissues and lymph nodes.

CT scan (computed tomography): This test uses a special x-ray machine that takes pictures from many angles. Before any pictures are taken, you may be asked to drink 1 to 2 pints of a liquid called oral contrast. This helps outline the intestine so that certain areas are not mistaken for tumors. You may also receive an IV (intravenous) line through which a different kind of contrast dye (IV contrast) is injected. This helps better outline structures in your body. A computer then combines these pictures into images of slices of the part of your body being studied. The CT scan can help show where stomach cancer is and where it has spread. CT scans can also be used to guide a biopsy needle into a place that might have cancer. The patient stays on the CT scanning table while a doctor moves a biopsy needle through the skin toward the tumor. A small piece of the tumor is removed and looked at under a microscope.

MRI scan (magnetic resonance imaging): MRI (magnetic resonance imaging): Provide detailed images of soft tissues in the body. They use radio waves and strong magnets instead of x-rays, which are absorbed and then released in a pattern formed as they penetrate through different types of body tissue and by certain diseases. A computer translates the pattern into a very detailed image of parts of the body.

PET scan (positron emission tomography): a special type of scanner that uses a form of sugar that contains a radioactive atom. Because cancer cells in the body are growing rapidly, they absorb large amounts of the radioactive sugar. This allows for cancer cells to show up brighter in the images because they absorb more sugar than normal cells. PET scans are also useful to check if the cancer may have spread elsewhere in the body. PET can reveal spread of cancer to the liver, bones, adrenal glands, or some other organs. Some machines are able to perform both a PET and CT scan at the same time (PET/CT scan).

Chest x-rays: may be done to see whether the cancer has spread to the lungs.

Laparoscopy: A thin, flexible tube with a camera on the end is placed through a small cut (incision) at the side of the patient. It sends a picture of the inside of the abdomen to a video screen.

Lab tests: These may include a blood test called a complete blood count (CBC) to look for anemia (a low red blood cell count that may be caused by bleeding), and a fecal occult blood test, which looks for small amounts of blood in the stool.

Staging of Gastrointestinal cancers Cancer
When cancer cells break away from the primary (original) tumor and travel through the lymph or blood to other places in the body, another (secondary) tumor may form. This process is called metastasis. The secondary (metastatic) tumor is the same type of cancer as the primary tumor. For example, if breast cancer spreads to the bones, the cancer cells in the bones are actually breast cancer cells. The disease is metastatic breast cancer, not bone cancer.

The following stages are used for gastric cancer:

Stage 0 (Carcinoma in Situ)
In stage 0, abnormal cells are found in the inside lining of the mucosal (innermost) layer of the stomach wall. These abnormal cells may become cancer and spread into nearby normal tissue. Stage 0 is also called carcinoma in situ.

Stage I
In stage I, cancer has formed. Stage I is divided into stage IA and stage IB, depending on where the cancer has spread.

• Stage IA: Cancer has spread completely through the mucosal (innermost) layer of the stomach wall.
• Stage IB: Cancer has spread:
• completely through the mucosal (innermost) layer of the stomach wall and is found in up to 6 lymph nodes near the tumor; or
• to the muscularis (middle) layer of the stomach wall.

Stage II
In stage II gastric cancer, cancer has spread:

• completely through the mucosal (innermost) layer of the stomach wall and is found in 7 to 15 lymph nodes near the tumor; or
• to the muscularis (middle) layer of the stomach wall and is found in up to 6 lymph nodes near the tumor; or
• to the serosal (outermost) layer of the stomach wall but not to lymph nodes or other organs.

Stage III
Stage III gastric cancer is divided into stage IIIA and stage IIIB depending on where the cancer has spread.

• Stage IIIA: Cancer has spread to:
• the muscularis (middle) layer of the stomach wall and is found in 7 to 15 lymph nodes near the tumor; or
• the serosal (outermost) layer of the stomach wall and is found in 1 to 6 lymph nodes near the tumor; or
• organs next to the stomach but not to lymph nodes or other parts of the body.
• Stage IIIB: Cancer has spread to the serosal (outermost) layer of the stomach wall and is found in 7 to 15 lymph nodes near the tumor.

Stage IV
In stage IV, cancer has spread to:

• organs next to the stomach and to at least one lymph node; or
• more than 15 lymph nodes; or
• other parts of the body.

The management of gastrointestinal cancer depends on the site of the tumor several factors. Depending on the stage of the disease and these other factors, such as type, size, location of tumor, and general health, the main treatment options for people with gastrointestinal cancers include:

SURGERY is a common treatment of all stages of gastric cancer. The following types of surgery may be used:

• Subtotal gastrectomy: Removal of the part of the stomach that contains cancer, nearby lymph nodes, and parts of other tissues and organs near the tumor. The spleen may be removed. The spleen is an organ in the upper abdomen that filters the blood and removes old blood cells.
• Total gastrectomy: Removal of the entire stomach, nearby lymph nodes, and parts of the esophagus, small intestine, and other tissues near the tumor. The spleen may be removed. The esophagus is connected to the small intestine so the patient can continue to eat and swallow.

If the tumor is blocking the stomach but the cancer cannot be completely removed by standard surgery, the following procedures may be used:

• Endoluminal stent placement: A procedure to insert a stent (a thin, expandable tube) in order to keep a passage (such as arteries or the esophagus) open. For tumors blocking the passage into or out of the stomach, surgery may be done to place a stent from the esophagus to the stomach or from the stomach to the small intestine to allow the patient to eat normally.
• Endoluminal laser therapy: A procedure in which an endoscope (a thin, lighted tube) with a laser attached is inserted into the body. A laser is an intense beam of light that can be used as a knife.

RADIATION THERAPY
External beam radiation treatment is most often used in conjunction with surgery, but it can also be combined with chemotherapy as an alternative to surgery.

• Neoadjuvant therapy: radiotherapy (sometimes along with chemotherapy) delivered prior to surgery to shrink a tumor and make it more manageable
• Adjuvant therapy: radiotherapy (sometimes along with chemotherapy) given after surgery to kill any cancer cells that may have been left behind
• Primary therapy: radiotherapy given as the main treatment.
• Concurrent (chemoradiation) therapy: radiotherapy given along with chemotherapy

External beam radiation therapy involves focusing a beam of ionizing radiation to the tumor while sparing the surrounding tissue. It is delivered by a series of painless outpatient treatments over several weeks. Treatments are given Monday through Friday and last less than 30 minutes.

3-Dimensional Conformal Radiotherapy (3D-CRT) is a method of treatment delivery that combines multiple radiation treatment fields using 3-Dimensional computer planning to produce a high-dose area of radiation that conforms to the shape of the area to be treated. This technique allows the tailoring of delivery of precise doses of radiation to the targeted area while sparing surrounding normal healthy tissue.

Intensity modulated radiation therapy (IMRT) is an advanced form of 3D-CRT that modifies the intensity or strength of each radiation beam. It utilizes a sophisticated system of treatment delivery that allows a precise adjustment of the radiation beam intensity to the tissue within the target area while minimizing effects on surrounding tissue. This may allow for a higher dose of radiation to be delivered to the tumor from multiple angles.

IGRT or Image Guided Radiation Therapy is another technology that can also be used to ensure better targeting of daily radiation treatments. 

Stereotactic body radiation therapy (SBRT) is a specialized form of 3D-CRT that delivers high doses of radiation over a period of five to ten days. Instead of giving small doses of radiation each day for several weeks, SBRT involves delivery of very focused beams of high-dose radiation. Several beams are aimed at the tumor from different angles. In order to precisely target the radiation, a specially designed body frame is used for each treatment. This helps to minimize the movement of the lung tumor during breathing. . If it is delivered in a single fraction it is known as stereotactic body radiosurgery. Like other forms of external radiation, these treatments are painless. It can be used for some very early stage (small) lung cancers when surgery isn't an option usually for other medical reasons. There is emerging data that have demonstrated that this technique may provide an alternative first-line approach to surgery.

Brachytherapy (internal radiation therapy) is used most often to shrink tumors to relieve symptoms caused by the cancer. In some cases it may be part of a larger treatment regimen trying to cure the cancer.

High-dose-rate brachytherapy (HDR): a small source of radioactive material is placed directly into the cancer or into the airway next to the cancer. It involves placing thin plastic tubes (catheters) into the area to treat. These tubes are connected to a special HDR delivery machine. A small amount of radioactive material is computer-driven through these catheters allowing a high dose of radiation to be delivered to a small, precise area while sparing surrounding normal healthy tissue. The radiation and catheters are removed at the end of each treatment.

CHEMOTHERAPY
Is the use of anticancer drugs injected into a vein or taken by mouth to destroy certain types of tumors and is utilized in different stages of lung cancer. These drugs enter the bloodstream and go throughout the body, making this treatment useful for cancer that has spread (metastasized) to distant organs. Depending on the type and stage of lung cancer, chemotherapy may be used in different situations (see Radiation Therapy Section):

• Neoadjuvant therapy: chemotherapy (sometimes along with radiation therapy) delivered prior to surgery to shrink a tumor and make it more manageable
• Adjuvant therapy: chemotherapy (sometimes along with radiation therapy) given after surgery to kill any cancer cells that may have been left behind
• Primary therapy: chemotherapy given as the main treatment (sometimes along with radiation therapy) for more advanced cancers or for some people who are not deemed to be surgical candidates.

Possible Treatment Side Effects
Dr. Farber, Dr. Spierer, and their staff at The Farber Center for Radiation Oncology will discuss potential side effects with you before, during, and after treatment, and ensure that your experience is personalized.