Treatment of primary gastric lymphoma: experience in the National Cancer Center Hospital, Tokyo.

The single institutional experience of the treatment of primary gastric lymphoma is presented in chronological order. Between 1963 and 1986, 74 patients were treated with various uncontrolled methods and resection line involvement was seen in seven cases. Between 1987 and 1995, a prospective study was conducted employing total gastrectomy with systematic lymphadenectomy, followed by chemotherapy for cases with lymph node metastasis. Fifty patients were enrolled and the 5-year survival rate was 86%. Thorough histological examinations of the resected specimens revealed multiple foci in the stomach and nodal involvement in 36% and 50% of cases, respectively. Since 1995, the effects of eradication of Helicobactor pylori have been examined in association with the introduction of the histological diagnosis of mucosa-associated lymphoid tissue (MALT) lymphoma. Special attention should be paid to the elevated type tumors because they could metastasize to lymph nodes preserving the features of "low-grade" MALT lymphoma.