Chemotherapy for management of localised high-grade gastric B-cell lymphoma: how much is necessary?

BACKGROUND: Recent data suggest that chemotherapy with the cyclophosphamide, doxorubicin, vincristine and prednisone (CHOP) regimen is a highly effective treatment for localised primary gastric lymphoma of diffuse large B-cell histology (DLBCL). We have reported that the large majority of patients achieve complete remission (CR) following three cycles of treatment, and now provide an updated series with special emphasis on patients receiving only short-term chemotherapy. PATIENTS AND METHODS: All patients with a histologically verified diagnosis of gastric DLBCL in stages EI and EII(1) undergoing chemotherapy with the CHOP regimen were evaluated. Data analysed included clinical stage, histology [presence of an additional mucosa-associated lymphoid tissue (MALT) component], evidence of Helicobacter pylori infection, H. pylori eradication, time to CR, survival and regular restaging (i.e. after three and six cycles, respectively). RESULTS: A total of 37 patients with DLBCL of the stomach with localised disease were identified, five of whom also had a MALT component. Twenty-two patients presented with stage EI and 15 with stage EII(1) disease. All patients were given chemotherapy as sole management of their lymphoma; 36 patients received CHOP, while one patient was given CHOP along with rituximab. Thirty-two (86%) achieved a CR after a maximum of three cycles, while only four patients had to be given six cycles for CR. In total, nine of 37 patients (24%) discontinued therapy earlier than scheduled: one patient received one cycle, two received two, six received three and one patient received four cycles. Two of these patients stopped treatment due to toxicity, i.e. protracted thrombocytopenia or chemotherapy extravasation. One additional patient died after one cycle of treatment; autopsy disclosed no signs of remaining lymphoma. Three patients have died after a median follow-up of 39 months (including the one patient who discontinued therapy after one cycle of treatment), while the remaining 34 patients are alive without evidence of disease. Twenty-four out of 37 patients (65%) had also undergone H. pylori eradication (including six of nine patients receiving only short-term treatment). CONCLUSIONS: DLBCL of the stomach appears to be a highly chemosensitive disease. Our data question the need for full-term CHOP treatment in patients achieving CR upon first follow-up. However, recent data suggest that additional H. pylori eradication might have contributed to the excellent results achieved in our series.