Survival outcomes in aggressive non-Hodgkin's lymphoma according to the International Prognostic Index.

Purpose: To retrospectively analyse the disease-free survival (DFS) and overall survival (OS) according to the International Prognostic Index (IPI) risk groups in patients with aggressive non-Hodgkin's lymphoma (A-NHL) treated at the Institute of Oncology, Istanbul University between 1989-1998.

Patients And Methods: The records of 201 patients with A-NHL and aged 15 years and over were retrospectively analysed. Features evaluated for potential prognostic importance for DFS and OS included sex, age, tumor stage, performance status (PS), "B" symptoms, bone marrow infiltration, number of extranodal disease sites, size of the largest tumor, histologic grade, erythrocyte sedimentation rate (ESR), and serum levels of lactate dehydrogenase (LDH), albumin and beta2-microglobulin. The International Working Formulation system and the Ann Arbor staging system were used for histologic and staging classifications, respectively. Kaplan-Meier, log-rank and Cox's methods were used for statistical analyses.

Results: Sixty-six percent of the patients were classified in the low risk group; 23% in the low-intermediate risk group; 9% in the intermediate-high risk group; and 2% in the high risk group. The median follow-up was 25.9 months (range 1-150 months). Five-year DFS and OS were 41% and 47%, respectively, in all patients. According to IPI, based on the age, tumor stage, LDH level, PS, and extranodal involvement in the identified 4 risk groups of all patients and all ages, the 5-year DFS and OS rates were 66-51%, 49- 43%, 40-34%, and 0%, respectively. Patients in the lowintermediate and intermediate-high risk groups had a worse survival outcome than low risk patients (p=0.001).

Conclusion: The IPI can be used in the selection of appropriate therapeutic strategy for individual patients. IPI is the most acceptable prognostic system, but being not the ideal one, is still being under critical discussion.