Diagnostic and prognostic utility of PD-1 in B cell lymphomas

Article type: Research Article

Authors: Muenst, S. | Hoeller, S. | Willi, N. | Dirnhofer, S. | Tzankov, A.

Affiliations: Institute of Pathology, University Hospital, Basel, Switzerland | Institute of Pathology, Cantonal Hospital Liestal, Switzerland

Note: [] orresponding author: PD Dr. A. Tzankov, Institute of Pathology, University Hospital Basel, Schönbeinstrasse 40, 4031 Basel, Switzerland. Tel.: +41 61 2652757; Fax: +41 61 2653194; E-mail: [email protected]

Abstract: Aims: Programmed death-1 (PD-1) is expressed by germinal center-associated helper T-cells and acts as a negative regulator of the immune system. PD-1 is encountered on tumor cells of angioimmunoblastic T-cell lymphoma and is a postulated diagnostic marker in chronic lymphocytic leukemia (CLL/SLL). Recent data suggest prognostic importance of PD-1 in follicular lymphoma (FL). We assessed the diagnostic potential and the prognostic importance of PD-1 in B-cell lymphomas. Methods: Distribution of PD-1+ lymphocytes in B-cell lymphomas was studied on 403 cases. Correlation with known biologic and clinical key data was performed. Prognostic cut-off scores were determined by receiver operating curve analysis. Results: PD-1+ tumor-infiltrating lymphocytes were numerous in extranodal marginal zone lymphomas and FL. Their amount decreased from FL grade 1 to grade 3 and to FL with transformation to diffuse large B-cell lymphoma. An increased amount of PD-1 tumor-infiltrating lymphocytes above the prognostic cut-off score (> 2.8%) was a positive prognostic factor of disease-specific survival (DSS) in FL-patients. Five percent of the studied 66 CLL/SLL cases showed unequivocal PD-1 positivity of neoplastic cells. Conclusions: Increased number of PD-1+ tumor-infiltrating lymphocytes is associated with significantly improved DSS in FL and may be useful to predict its heterogeneous clinical behavior. PD-1 has probably limited diagnostic value for primary histopathological CLL/SLL diagnostics.

DOI: 10.3233/DMA-2010-0725

Journal: Disease Markers, vol. 29, no. 1, pp. 47-53, 2010