Soluble MIC-A, IPI, and response to treatment strongly predict survival in patients with germinal center diffuse large B cell lymphoma.

ABSTRACT

Diffuse large B-cell lymphoma (DLBCL) is the most frequent lymphoma. MIC-A and MIC-B are the natural ligands for NKG2D, a receptor expressed in NK cells. MIC-A soluble isoforms (sMICA) have been described in different malignancies. OBJECTIVES: To analyze lymphocyte subsets and sMIC-A in germinal center DLBCL. MATERIALS AND METHODS: sMICA, sMICB, and peripheral blood lymphocyte subsets (CD4+, CD8+, NK, NKT, γδ T cells, and dendritic cells) were analyzed in 59 patients and 60 healthy donors. RESULTS: Patients had decreased numbers of type 1 and type 2 dendritic cells, NK, iNKT, CD4 T, and CD8 T cells, and higher levels of sMIC-A. The 2-year PFS for high IPI scores and high sMIC-A was 24% and 28%, respectively. The 2-year OS for high IPI scores and high sMIC-A was 42% and 33%. The 2-year PFS and OS for patients not achieving response to treatment were 0% and 10%, respectively. The MICPI score (one point each for high IPI score and high sMIC-A) showed that those patients summing two points had worse PSF and OS. CONCLUSIONS: Patients with DLBCL have decreased numbers of peripheral lymphocyte subsets and high levels of sMIC-A. The addition of sMIC-A to IPI could improve its prognostic relevance.