This page was reviewed under our medical and editorial policy by
Maurie Markman, MD, President, Medicine & Science
This page was reviewed on November 12, 2021.
Gastrointestinal lymphoma refers to lymphoma that starts in the digestive tract, including in the stomach, small intestine, large intestine (colon and rectum) and esophagus.
Lymphoma is a cancer of the lymphatic system, a widespread network of organs and tissues that make up part of the larger immune system, the body’s shield against diseases and other ailments. The lymphatic system transports lymph, a fluid that contains infection-fighting cells.
Lymph nodes are the most fundamental lymph system structures. These small, round clusters are found in the neck, armpit, groin and many other places. Their job is to produce immune system cells called lymphocytes. Many other tissues and structures involved in the lymphatic system are spread throughout the body, and lymphoma can begin in any of these places.
Lymphoma can start in the digestive tract wherever lymph tissue is present. Lymphoma types can have substantial differences, depending on:
While there are different types of gastrointestinal lymphomas, most are B-cell non-Hodgkin lymphomas. Lymph tissue contains two main types of immune system cells: B lymphocytes (B-cells) and T lymphocytes (T-cells). A majority of all lymphomas affect B-cells, including most gastrointestinal lymphomas.
Of all the lymphoma types that can occur in the gastrointestinal tract, two are the most common:
MALT lymphomas account for more than 50 percent of gastric non-Hodgkin lymphomas, according to a study in the Journal of Gastrointestinal Oncology. These cancers begin within lymph tissue found in the lining of the stomach. They tend to grow slowly and respond well to treatment. Sometimes, MALT lymphomas can transform into the more aggressive DLBCL, but DLBCL can also arise on its own. About 40 percent to 70 percent of gastrointestinal lymphomas are DLBCL, according to the study.
Overall, gastrointestinal lymphoma is a rare disease, making up 1 percent of cancers that start in the gastrointestinal tract. Those who develop it are most often diagnosed between the ages of 50 and 70.
The stomach is the most common site for lymphoma to start within the digestive system, affecting about one in 100,000 people in Western countries, according to the National Organization for Rare Disorders (NORD).
After the stomach, the small intestine and the colon are the most common locations. Lymphomas that start in other parts of the digestive system, such as the esophagus or liver, are extremely rare.
Although it's not always possible to pinpoint the cause of gastrointestinal lymphoma, some risk factors may increase the risk for developing this disease.
Cancer stems from changes within the DNA. These mutations may be passed down within a family or triggered by environmental factors, such as cigarette smoke.
Mutations also occur randomly. Cells must copy their DNA every time they divide to make new cells, and this process may be imperfect. When DNA is copied incorrectly, a mutation may arise.
When mutations occur within certain immune system cells, they may turn into lymphoma cells. Lymphoma often comes from a mutation within an immune system cell that causes it to become abnormal and start replicating uncontrollably.
In the case of gastrointestinal lymphoma, cancer-causing mutations are often spurred by bacterial or viral infections, especially Helicobacter pylori (H. pylori) infections. About 90 percent of MALT lymphomas in the stomach are linked to a chronic H. pylori infection, according to NORD.
When this bacteria persists in the digestive tract over a long time, the intestinal lining becomes inflamed. Long-term inflammation may trigger the growth of immune system cells, which may then turn into lymphoma cells. Many people are infected with H. pylori, but few contract MALT lymphoma, suggesting that weakened immunity and other factors may also contribute to the development of this cancer.
Besides chronic H. pylori infection, other factors that may increase the risk of developing gastrointestinal lymphoma include:
The potential symptoms of gastrointestinal lymphoma vary widely, and some patients may experience no apparent symptoms. The symptoms are often nonspecific and may be seen as signs of another ailment or condition.
When symptoms do occur, they may include:
Abdominal pain is a common symptom of gastrointestinal lymphoma. The pain stems from the presence of a growing mass, which may also cause a blockage. According to a study in the journal, BMJ Open Gastroenterology, abdominal pain occurs in about 45 percent to 65 percent of patients with gastrointestinal lymphoma.
Other potential symptoms are rarer, but may include:
The symptoms of gastrointestinal lymphoma also depend on the cancer’s location. For example, difficulty swallowing may indicate esophageal lymphoma, which is an infrequent occurrence.
Diagnosing gastrointestinal lymphoma may be complicated, because there are many different types.
A cancer diagnosis often starts with a general physical examination to look for an abnormal lump or bumps. The care team may also ask the patient a series of questions about his or her medical history, including symptoms, underlying conditions and current medications. Then, the patient likely undergoes a series of tests, such as blood tests, biopsies and imaging tests.
Blood tests: A complete blood count (CBC)—which measures how many red blood cells, white blood cells and platelets are present in the blood—is often helpful in diagnosing lymphoma, as the cancer can affect blood cell levels. Blood samples may also be tested for specific proteins, such as lactate dehydrogenase (LDH), which can indicate whether the cancer is fast- or slow-growing, and the presence of viruses and bacteria, including H. pylori, hepatitis B and hepatitis C.
Biopsies and endoscopy: An upper endoscopy is useful in diagnosing this type of lymphoma because the procedure provides a look at the inside of the gastrointestinal tract while also allowing for biopsy samples to be taken. The test is often performed by a gastroenterologist, who is an expert in digestive diseases. Biopsy samples are analyzed under a laboratory microscope to see whether they contain cancerous cells. If a biopsy reveals cancer, the lab specialists take a deeper look at the cells to find out more information, such as the exact type and subtype of the cancer and whether it is slow-growing or aggressive.
Other imaging tests: While a biopsy is needed to confirm the diagnosis and establish the type of cancer, imaging tests may provide information about the extent of cancer spread. The imaging techniques that doctors may use to help diagnose gastrointestinal lymphoma include those listed below.Computed tomography (CT) scan: A CT scan may identify enlarged lymph nodes that may contain cancer cells.
Positron emission tomography (PET)/CT scan: PET/CT scans show whether or not cancer has spread and where it may have spread. They also may help determine whether treatment is working.
During or after the diagnostic process, the care team also needs to determine the cancer’s stage, which describes the extent of spread within the body. Many of the tests used to diagnose gastrointestinal lymphoma provide information on its stage.
The cancer stage helps inform treatment and patient outcomes. It generally corresponds with the cancer’s severity—advanced stages tend to have poorer outcomes.
According to summary guidelines in the journal Digestive and Liver Disease, about 70 percent of gastrointestinal lymphomas are early-stage or localized, meaning that the cancer hasn’t spread far beyond where it started.
After the diagnostic and staging process—when the care team has determined the type of lymphoma, where it’s located and its stage—they will develop a treatment plan. The patient's health history, preferences and input play an essential role in treatment decisions. It’s important to understand the benefits and drawbacks of treatment options and to ask questions if any of the information is unclear.
Treating gastrointestinal lymphoma is a team effort that often requires the expertise of several different types of doctors. For example, if the patient plans to undergo chemotherapy, he or she will likely work with a medical oncologist who specializes in anti-cancer drugs. The core members of the cancer care team may also include a gastroenterologist and a hematologist, who are trained to treat gastrointestinal diseases and blood-based conditions, respectively. The patient may also consult with other medical professionals along the way, including nurses, psychologists and oncology dietitians.
Besides the patient's personal preferences, overall health and age, the key factors that determine a treatment plan include:
Below are some of the potential treatment options for gastrointestinal lymphoma.
Watch and wait: For some cases of gastrointestinal MALT lymphoma, doctors may recommend withholding treatment unless there are signs that the disease is progressing. MALT lymphoma tends to be slow-growing and can take many years to cause problems or symptoms. A watch-and-wait protocol involves regular checkups to look for signs of disease progression. The benefit of this method is that it allows patients to avoid cancer treatments and their side effects until they become necessary.
Antibiotics: For almost all cases of gastrointestinal MALT lymphoma, the first treatment used is antibiotics. Doctors typically prescribe a regimen of clarithromycin combined with amoxicillin or metronidazole to eradicate the H. pylori bacteria from the digestive system. For early-stage cancer, antibiotics may be the only treatment needed. Antibiotics successfully treat more than 70 percent of early-stage MALT lymphomas linked to H. pylori, according to the study in BMJ Open Gastroenterology.
Patients treated with antibiotics alone need regular checkups with blood tests and endoscopies to ensure that the bacteria or lymphoma hasn’t returned.
Radiation therapy and chemotherapy: Radiation therapy and/or chemotherapy may be a part of treatment for gastrointestinal lymphoma under any of the following circumstances:
For patients with MALT lymphoma that isn’t eradicated by antibiotics, doctors typically recommend external beam radiation therapy to the stomach. Advanced-stage gastrointestinal MALT lymphoma may be treated with a combination of radiation therapy and chemotherapy. For cases of the more-aggressive gastrointestinal DLBCL, higher doses of radiation may be used in combination with chemotherapy.
For gastrointestinal DLBCL, chemotherapy is the standard treatment. Typically, doctors will give patients a chemotherapy regimen of five drugs, called R-CHOP, which stands for rituximab, cyclophosphamide, hydroxydaunorubicin, Oncovin and prednisone. Rituximab is a type of immunotherapy that helps the body recognize and attack lymphoma cells. The other four are chemotherapy drugs. The drugs are usually administered at three-week intervals. After an R-CHOP regimen, some patients with gastrointestinal DLBCL may undergo radiation therapy to the stomach.
Gastrointestinal lymphoma is a relatively rare cancer, and it can develop in many forms. Outcomes vary depending on where the cancer starts, and the gastrointestinal tract has many parts. Different factors—such as the cancer’s subtype, the type of cell the cancer begins in, and how aggressive the cancer is—influence outcomes. Since gastrointestinal lymphomas can display very different characteristics, it’s difficult to estimate the average survival rate of patients.
According to a report from the National Library of Medicine, 90 percent of patients with low-grade gastrointestinal MALT lymphomas involving the mucosal and submucosal layers live for at least 10 years following diagnosis.
For patients with high-grade gastrointestinal MALT lymphoma, survival rates depend on how many risk factors they carry from the list below.
Ninety-nine percent of patients with none of these risk factors live five years or more after diagnosis. Those who had one risk factor had a 93 percent five-year survival rate. For patients with two or more risk factors, the overall five-year survival rate was 64 percent.
Patients who have recently been diagnosed with gastrointestinal lymphoma and are confused about the disease or its outcomes should talk to their care team. Diagnosing and treating gastrointestinal lymphoma is complicated, and knowing the specific characteristics of each patient’s cancer will allow the care team to provide the most accurate information.