NUCLEAR MORPHOMETRY, IMMUNOHISTOCHEMICAL STAINING WITH KI-67 ANTIBODYAND MITOTIC INDEX IN THE ASSESSMENT OF PROLIFERATIVE ACTIVITY AND PROGNOSIS OF PRIMARY MALIGNANT MELANOMAS OF THE SKIN

Nuclear morphometry, immunohistochemical staining with Ki-67 antibody and mitotic index were studied in primary cutaneous malignant melanoma s. The number of Ki-67 positive cells/200 tumor cells did not correlat e with any nuclear morphometrical parameters, and it only approached b ut did not reach significant correlation with melanoma thickness accor ding to Breslow. The nuclear area, short axis and long axis correlated with melanoma thickness, but the nuclear axis ratio (which reflects t he sphericity of nuclei) and melanoma thickness did not show significa nt correlation. Mitotic index was higher in thick melanomas and in mel anomas with high Ki-67 positivity, large nuclear area, long nuclear sh ort axis, and small nuclear axis ratio. In Cox's stepwise proportional hazard model, melanoma thickness and the nuclear axis ratio were sign ificant independent prognostic factors for patient survival, while the nuclear area, short axis and long axis, gender, age, Clark level, mit otic index and Ki-67 positivity lacked significant independent prognos tic value. The results suggest that the proliferative activity of tumo r cells does not alone explain the great importance of tumor thickness as prognosticator in melanoma. The thickness of melanoma measured acc ording to Breslow and the nuclear axis ratio are more efficient progno sticators in melanoma than parameters associated with proliferation.