Correlation of Minichromosome Maintenance Protein 6 Expression Rate and Clinical Outcome in Patients With Hodgkin's Lymphoma

Minichromosome maintenance complex component 6 (MCM-6) is one of the six proteins of the MCM family, which are involved in the initiation of DNA replication, represents a marker of proliferating cells. The goal of this study was to evaluate the prognostic relevance of the neoplastic cell proliferation rate in patients with Hodgkin's lymphoma (HL). We evaluated the formalin-fixed paraffin-embedded lymph node biopsy specimens from 55 patients by using monoclonal antibody against MCM-6 and compared these findings with clinical data and treatment outcome. Median of MCM-6 expression was 85% (range: 35%-99%). In multivariate analysis, MCM-6 expression, B symptoms, and age were not statistically significant predictor for relapse in contrary to response (P=.001) and stage of disease (P=.048). Patients with lower MCM-6 expression rates showed higher relapse rate and lower disease-free survival (DFS). Meanwhile, patients with MCM-6 expression less than 85% showed shorter DFS (P=.031). We hypothesize that in group of patients with lower MCM-6 expression rate, a larger proportion of proliferating malignant cells are arrested in the very early phase of mitosis, in comparison to the group of patients with higher MCM-6 expression, and this could imply a shorter and probably higher relapse rate in the former group.