High-Grade Primary Gastric Lymphoma: A Retrospective Review of Clinicopathologic Features and Prognostic Factor Analysis in 214 Patients with High-Grade Gastric Lymphoma.

Stomach is the most common site of primary extranodal lymphoma. In addition to the ‘classical’ indolent marginal zone lymphoma of the mucosa-associated lymphoid tissue (MALT)-type, aggressive histologies are also encountered in the stomach, the majority being classified as diffuse large B-cell lymphoma (DLBCL). We reviewed all patients treated at four institutes between 1990 and 2004 for a NHL exhibiting primary gastric involvement with high-grade pathologies to analyze clinicopathologic features and clinical prognostic factors. A survey of 444 gastric lymphoma including MALT-lymphoma who had been diagnosed identified 260 patients with high-grade gastric lymphoma. Among these 260 cases, 214 high-grade gastric lymphoma patients who had been treated and evaluated were included in this analysis. T-cell lymphomas and mantle cell lymphomas were included in this analysis to reflect poor outcomes of these subtypes. The median age of the 119 male and 95 female patients was 55 years (range 21–81 years), many of the patients (63%) had a good performance status (0 or 1). The most of the patients (87%) had DLBCLs. Other pathologic subtypes were as follows: mantle cell lymphoma in 7 patients, Burkitt lymphoma in 5 patients, other high-grade B-cell lymphoma in 2 patients, and T-cell lymphoma in 14 patients (6.5%). Among these 187 DLBCL patients, 22 patients (10%) included low-grade component. Manay of the patients (63%) showed localized stage I or II diseases according to the Mushoff staging system. According to the International Prognostic Index (IPI), 66% of the patients showed low or low-intermediated risk, 34% showed high or high-intermediated risk. All the patients treated with surgery and/or combination chemotherapy with or without radiotherapy. The main chemotherapy was CHOP or CHOP-like regimens. Actually, through this analysis, we observed the change of treatment trend. Since 2000, gastric resections were performed in only 13 patients, who had been complicated with bleeding or perforation. The overall response rate to treatment was 82% (Complete Response (CR); 69%, Partial Response (PR); 13%). The median Progression-Free Survival (PFS) was 54 months (95% C.I.; 7–102). The median Overall Survival (OS) was 90 months (95% C.I.; 46–135). The prognostic factor analysis showed IPI had independent prognostic significance for OS by Cox-regression test (p = 0.000). We also identified the presence of ascites as independent prognostic factor, as well as IPI (p = 0.038). According to the subgroup analysis, M1 node (by AJCC staging system) positivity on pre-treatment CT-scanning was associated with poor clinical outcome (p = 0.0000 by log-rank test) for localized stage I or II patients. In conclusion, our cohort of patients represents one of the most important series that show the clinicopathologic feature, treatment outcome, and prognostic factors of high-grade primary gastric lymphoma.