Histological features of ocular adnexal lymphoma (REAL classification) andtheir association with patient morbidity and survival

Background-The histological characteristics of ocular adnexal lymphomas hav e previously provided only a limited guide to clinical outcome for affected patients. This clinicopathological relation was reexamined using the Revis ed European American Lymphoma (REAL) system to classify the tumours in a la rge cohort of patients. Methods-The biopsies and clinical follow up data for 192 patients with ocul ar adnexal lymphoma were reviewed, the biopsies being regraded in accordanc e with the REAL classification. For each of five histological groups, logis tic regression analysis was used to determine the odds ratios (OR) for the presence of systemic disease at the time of orbital diagnosis and Cox regre ssion analysis was used to assess the hazard ratios (HR) for disseminated d isease and lymphoma related death. For 108 patients in whom extraorbital sp read occurred, the histological category of lymphoma was compared with the sites of dissemination. Results-At presentation, the frequency of previous or concurrent extraorbit al disease increased from marginal zone lymphoma (OR 1.0), diffuse lymphopl asmacytic/lymphoplasmacytoid lymphoma (OR 2.3), follicle centre lymphoma (O R 3.8), diffuse large B cell lymphoma (OR 4.0) to other histological lympho ma variants (OR 26.8). For all histological types, the estimated risk of ex traorbital disease and lymphoma related death continued for many years and the proportion of patients with at least one extraorbital recurrence after 5 years was 47% for MZL, 48% for LPL, 64% for FCL, 81% for DLCL, and 95% fo r other lymphoma variants. The corresponding estimated rates for 5 year lym phoma related mortality were 12%, 19%, 22%, 48%, and 53% respectively. Conclusions-Patients with ocular adnexal lymphoma can be classified by REAL into five distinct groups, which show a progressive increase in the risks of extraorbital disease at diagnosis, of disease dissemination with time, a nd of tumour related death.