Metachronous gastric MALT lymphoma and early gastric cancer

Synchronous gastric MALT lymphoma and gastric adenocarcinoma of fundic gland type arising from a hamartomatous inverted polyp in a Helicobacter pylori naive patient

We present a rare case that showed the coexistence of gastric cancer and mucosa-associated lymphoid tissue (MALT) lymphoma in Helicobacter pylori-naive stomach. A 72-year-old man was followed up after surgery for epithelial carcinoma of the glottis at the Department of Otolaryngology. He underwent an upper gastrointestinal endoscopy for an abnormal PET-CT accumulation, which revealed gastric adenocarcinoma of fundic gland type in the gastric fundus and MALT lymphoma in the upper gastric body. Hence, we performed an endoscopic submucosal dissection for gastric cancer and diagnosed gastric adenocarcinoma of fundic gland type derived from a hamartomatous-inverted polyp. Subsequently, Gastric MALT lymphoma was treated with radiation therapy because the API2-MALT1 gene was positive and the Helicobacter pylori infection was negative. A complete response was observed. Even in Hp-naive stomachs, cases such as the present case are complicated by special types of gastric cancer and MALT lymphoma, and endoscopic examination should be performed with these diseases in mind.

Long-term treatment of localized gastric marginal zone B-cell mucosa associated lymphoid tissue lymphoma including incidence of metachronous gastric cancer

BACKGROUND AND AIM

According to a few recent reports on the long-term clinical outcome of gastric marginal zone B-cell mucosa associated lymphoid tissue lymphoma (MALT lymphoma); localized gastric MALT lymphoma generally has a favorable prognosis. However, the risk of metachronous gastric cancer has not been evaluated. In this study, we analyzed long-term outcomes of localized gastric MALT lymphoma including the incidence of metachronous gastric cancer.

METHODS

Between April 1996 and May 2008, 60 patients (31 men and 29 women; mean age 58.1 years) with localized gastric MALT lymphoma (stage I and II(1) according to Lugano classification) were analyzed retrospectively.

RESULTS

Forty-eight patients (82.6%) achieved complete remission by eradication therapy. Radiation therapy was conducted on eight patients as second-line treatment, and all of them achieved remission. The median follow-up period was 76 months (range, 12-157 months). One patient had local relapse after remission for 5 years and three patients developed early gastric cancer without recurrence of lymphoma (5%). All of the three gastric cancers appeared in the same areas where MALT lymphoma had been eradicated.

CONCLUSION

Eradication therapy and radiation therapy for localized gastric MALT lymphoma have a favorable long-term outcome, though regular follow-up endoscopy should be performed for detecting metachronous early gastric cancer.

Diagnosis and staging in gastrointestinal lymphoma

The diagnosis gastrointestinal lymphoma can be made on endoscopic biopsies in the vast majority of cases. Definitive subtyping of the lymphoma according to the WHO classification with the use of additional immunological and molecular markers is the cornerstone for further decision making. Several lymphomas may occur multifocally or show both small cell and large cell components. Therefore, a second endoscopy with an extensive biopsy protocol (mapping) may be mandatory. Staging procedures are required for therapeutic decision making and should include CT-scan, laboratory studies and bone marrow examination as required in other lymphomas. Additional studies must be performed depending subtype and localisation of the lymphoma. In gastric lymphoma endosonography reveals prognostic information. In marginal zone lymphoma of MALT-type attention to other MALT-sites and autoimmune diseases is necessary. In enteropathy-associated T-cell lymphoma screening for coeliac disease and enteroscopy are required. In several lymphomas (diffuse large B-cell lymphoma and mantle cell lymphoma) a PET-scan is considered as standard of care. The value of staging procedures after treatment is less well defined. At least in gastric lymphomas, histology is the gold standard after treatment and during follow-up.

Role of radiotherapy in the treatment of lymphomas of the gastrointestinal tract

In patients with gastrointestinal lymphoma the most frequently involved site is the stomach (60%-75% of cases), followed by the small bowel, ileum, cecum, colon and rectum. The most common histological subtypes are extranodal marginal zone B-cell lymphoma of the mucosa-associated lymphoid tissue (MALT) and diffuse large B-cell lymphoma (DLBCL). The role of radiotherapy is most definite in early stage gastric lymphoma. The therapeutic approach for patients with gastric Non Hodgkin lymphoma (NHL) has changed significantly over the last decades. The primary treatment of limited gastric MALT lymphoma consists of Helicobacter pylori eradication. In case of insufficient response to H. pylori eradication or in case H. pylori is absent, irradiation of the stomach and perigastric lymph nodes to a dose of 30-40Gy in 15-20 fractions is indicated. In patients with gastric DLBCL conservative treatment with anthracycline-based chemotherapy alone or in combination with involved-field radiotherapy has become the therapy of choice.