OBJECTIVE: We began a controlled clinical trial to assess efficacy and toxicity 
of surgery (S), surgery + radiotherapy (SRT), surgery + chemotherapy (SCT), and 
chemotherapy (CT) in the treatment of primary gastric diffuse large cell 
lymphoma in early stages: IE and II1.
SUMMARY BACKGROUND DATA: Management of primary gastric lymphoma remains 
controversial. No controlled clinical trials have evaluated the different 
therapeutic schedules, and prognostic factors have not been identified in a 
uniform population.
PATIENTS AND METHODS: Five hundred eighty-nine patients were randomized to be 
treated with S (148 patients), SR (138 patients), SCT (153 patients), and CT 
(150 patients). Radiotherapy was delivered at doses of 40 Gy; chemotherapy was 
CHOP (cyclophosphamide, doxorubicin, vincristine, and prednisone) at standard 
doses. International Prognostic Index (IPI) and modified IPI (MIPI) were 
assessed to determine outcome.
RESULTS: Complete response rates were similar in the 4 arms. Actuarial curves at 
10 years of event-free survival (EFS) were as follows: S: 28% (95% confidence 
interval [CI], 22% to 41%); SRT: 23% (95% CI, 16% to 29%); that were 
statistically significant when compared with SCT: 82% (95% CI, 73% to 89%); and 
CT: 92% (95% CI, 84% to 99%) (P < 0.001). Actuarial curves at 10 years showed 
that overall survivals (OS) were as follows: S: 54% (95% CI, 46% to 64%); SRT: 
53% (95% CI, 45% to 68%); that were statistically significant to SCT: 91% (95% 
CI, 85% to 99%); CT: 96% (95% CI, 90% to 103%)(P < 0.001). Late toxicity was 
more frequent and severe in patients who undergoing surgery. IPI and MIPI were 
not useful in determining outcome and multivariate analysis failed to identify 
other prognostic factors.
CONCLUSION: In patients with primary gastric diffuse large cell lymphoma and 
aggressive histology, diffuse large cell lymphoma in early stage SCT achieved 
good results, but surgery was associated with some cases of lethal 
complications. Thus it appears that CT should be considered the treatment of 
choice in this patient setting. Current clinical classifications of risk are not 
useful in defining treatment.