MIB-1 immunoreactivity correlates with blood vessel density and survival in disseminated malignant melanoma

The purpose of our current work was to evaluate the prognostic significance of tumor cell proliferation in advanced metastatic melanomas and to invest igate a possible correlation between the proliferation index and blood vess el density in metastatic tissue. Sixty patients with disseminated malignant melanoma treated with four-drug chemotherapy combined with interferon-alph a were included in this study. Proliferative activity and vascularity in me tastatic tissues were examined by immunohistochemistry with anti-Ki-67 (MIB -1) and anti-CD31 antibody, respectively. A significant relationship betwee n MIB-1 index and blood vessel number was detected (rho = 0.323, p = 0.013) . In survival analysis, the overall survival and disease-free survival were significantly longer (58 and 38 vs. 38 and 17 months) for patients with lo w MIB-1 immunoreactivity (p = 0.012 and p = 0.023, respectively). Likewise, the low MIB-1 labeling index was associated with the prolonged survival ca lculated from the initiation of the chemoimmunotherapy (12 vs. 7 months, p = 0.032). In multivariate Cox's proportional hazard analysis, MIB-1 positiv ity was an independent prognostic factor both for overall survival and for survival after beginning of the chemoimmunotherapy (p = 0.016 and p = 0.029 ).