Correlation between tumor cell prolieration and prognosis of primary cutaneous malignant melanoma in 127 patients

Objective: To investigate the correlations among Ki-67 expression, mitosis and other clinicopathological parameters of primary cutaneous malignant melanoma, and search for prognostic factors of malignant melanoma. Methods: Totally 127 cases of primary cutaneous malignant melanoma were collected from Beijing Cancer Hospital. Immunohistochemical study for Ki-67 was performed, and the mitosis was calculated referring to " hot spot" method recommended by the seventh edition of the American Joint Committee on Cancer (AJCC) melanoma staging system. The correlations of Ki-67 expression, mitosis and other clinicopathological parameters were analyzed, and the survival analysis of all these risk factors including TNM and Clark level was conducted based on follow up data. Results: The expression level of Ki-67 was associated with necrosis and Breslow thickness (P < 0. 05). Mitosis was correlated with Clark level and Ki-67 expression (P<0. 05). Univariate analysis indicated Ki-67 expression level (P = 0. 043), mitosis (P = 0.030) and TNM stage (P < 0. 001) might influence the survival of patients. However, multivariate analysis showed that the TNM staging was the only independent prognostic factor affecting survival. Conclusions: The prognosis of patients with primary cutaneous malignant melanoma was closely related to the TNM staging at the fist examination. Ki-67 expression and mitosis are two important clinicopathological parameters of primary cutaneous malignant melanoma.