NON-HODGKINS-LYMPHOMA IN SASKATCHEWAN - A REVIEW OF 10 YEARS EXPERIENCE

Background. The incidence and treatment of nonHodgkin's lymphoma (NHL) have changed in recent years. This study was intended to compare curr ent features with a previous study (1966-1975) and assess the impact o f these changes in our jurisdiction. Methods. Clinical features and tr eatment of 547 patients with NHL registered at our center from January 1980 through December 1989 were reviewed, including reassessment of h istologic type in each patient. Multivariate analysis of potential pre treatment prognostic factors was performed using the Cox proportional hazards model, and survival was analyzed in relation to treatment outc ome. Results. This review includes virtually all incident cases of NHL in a defined geographic area, representing an average annual incidenc e of 11.3/100,000 population. The male-to-female ratio was 1.1:1, medi an age was 65 years (range, 4-92 years). Median survival time (MST) of 482 patients with disease diagnosed antemortem was 4.8 years (95% con fidence interval [CI], 3.7-6.1 years), 52% of whom have died. Thirty-n ine percent of patients with disease classified by the International W orking Formulation (IWF) had low-grade disease (MST, 103 months); 27% had intermediate disease (MST, 62 months), and 30% had high-grade dise ase (MST, 35 months). Sixteen percent of patients had associated neopl asms: 4 acute leukemias, 35 skin cancers, and 37 miscellaneous solid t umors. Results of radiation therapy (RT), chemotherapy (CT), and combi ned CT/RT were analyzed. Survival correlated strongly with responsiven ess to treatment. Considering all patients treated with CT, anthracycl ine-containing CT was associated with the highest response rate, and s urvival time (more than 48 months) may have been affected by the addit ion of this agent. A survival advantage for patients with bulky Stage I and II disease treated with consolidative RT after CT is suggested, but not for more advanced stage disease. The proportional hazards mode l identified histologic type, disease stage, patient age, hemoglobin l evel, lactate dehydrogenase (LDH) level, bulky abdominal disease, and systemic ''B'' symptoms as significant independent prognostic factors influencing survival. Conclusions. The incidence of NHL has increased, and the survival of patients with high-grade disease has improved sig nificantly since the previous study. A high incidence of other associa ted malignancies was demonstrated in this group of patients with NHL. Recognition of prognostic factors should permit a rational application of innovative treatments for patients in unfavorable prognostic categ ories.