TREATMENT, PATTERNS OF FAILURE, AND SURVIVAL OF PATIENTS WITH STAGE-INODAL AND EXTRANODAL NON-HODGKINS-LYMPHOMAS, ACCORDING TO DATA IN THEPOPULATION-BASED REGISTRY OF THE COMPREHENSIVE CANCER CENTER WEST

BACKGROUND. Primary extranodal lymphomas (EN-NHLs) are a heterogeneous category of tumors that are considered to be different from primary n odal non-Hodgkin's lymphomas (N-NHLs). To what extent these difference s have clinical implications is currently not very clear, because know ledge of EN-NHL as a separate group is limited. METHODS. Using data fr om the Comprehensive Cancer Centre West (CCCW) population-based NHL re gistry in the Netherlands, N-NHL and EN-NHL patients were compared to determine differences in characteristics at diagnosis, responses to tr eatment, patterns of failure, and survival. RESULTS. At presentation, EN-NHL patients had poorer performance scores and more often bulky tum ors compared with N-NHL patients, resulting in poorer responses to tre atment (complete response rates were 72% and 84%, respectively; P = 0. 04) and inferior 5-year overall survival (49% and 63%, respectively; P = 0.003). Among EN-NHL patients, considerable variations in response, survival, and relapse rates were observed, with gastric NHL patients having the best and central nervous system NHL patients having the wor st prognosis (66% and 7% 5-year overall survival, respectively). Relap se rates for N-NHL and EN-NHL patients did not differ (39% and 36% 5-y ear relapse rates, respectively), whereas among EN-NHL patients consid erable differences in relapse rates were noted. Relapses among N-NHL p atients were mainly found in nodal sites, whereas recurrent disease in EN-NHL patients was mainly found in extranodal sites. CONCLUSIONS, In this population-based study, Stage I EN-NHL patients as a group had a poorer prognosis than N-NHL patients. However, among EN-NHL patients, considerable differences in response, relapse risk, and survival were observed. The failure analysis conducted in this study suggests that patterns of dissemination for N-NHL and EN-NHL are different. Cancer 1 998;83:1612-9. (C) 1998 American Cancer Society.