Outcomes and prognostic factors in marginal zone lymphoma: Case comprehensive cancer center cumulative experience of 358 cases.

8554 Background: MZL are uncommon B-cell lymphomas. The outcomes and prognostic factors of MZL remain poorly defined. Methods: We retrospectively identified 485 cases of MZL diagnosed between 1994-2014 from 2 institutions. Diagnoses had been confirmed by expert hematopathologists. We excluded 127 cases because of limited data and overlapping features with other lymphoma subtypes. Results: Of the 358 patients (pts) included in the analysis, 216 (60%) had extranodal MZL (EMZL) with most EMZL arising from stomach (32%), 56 (16%) nodal MZL (NMZL), 64 (18%) splenic MZL (SMZL), and 22 (6%) had typical MZL phenotype but were unclassifiable. Median age was 66 (range 13-95) years, 171 (48%) pts had stage III/IV disease at diagnosis. B-symptoms were present in 33 (9%) pts and 65 (18%) had > 4 nodal sites (LN) involved. Median time from diagnosis to treatment was 33 (2-1883) days and median duration of follow-up was 40.3 (2.2-236.4) months. Among treated pts, initial treatment was rituximab (R) (33%), chemotherapy +...