Immunohistochemical Detection of CD95L (Fas Ligand) in Mantle Cell Lymphoma: A Prognostic Factor for Clinical Outcome.

Mantle cell lymphoma is a malignant lymphoma associated with a relatively aggressive clinical course and a median overall survival time of 3–4 years. Proliferation indices are important prognostic factors in the clinical outcome. We investigated immunohistochemically the expression of the apoptotic marker CD95L (Fas Ligand) in relation to the clinical course. Biopsy specimen from 69 untreated patients enrolled in two multicenter prospective trials were investigated immunohistochemically with monoclonal antibodies against CD20, CD5, CD3, CD23, cyclin D1, CD95L. The CD95L expression was analyzed into three groups: negative, weak positive and strong positive. The expression was compared with the overall survival data analysed according to Kaplan and Meier. Patients with mantle cell lymphoma that had negative and weak positive CD95L expression had a median overall survival time of 32.0 months compared to 18.3 months for patients with a strong CD95L expression. The Kaplan-Meier analysis showed a significant difference in the overall survival time between the patients with strong CD95L expression and the group of patients with negative or weak positive tumor cells (p<0.0038). Based on these findings, the immunohistochemical detection of CD95L in mantle cell lymphoma is a prognostic factor.