Analysis of nuclear DNA and morphometry, and proliferating cell nuclear antigen in primary and metastatic malignant melanoma.

Sections from 23 primary malignant melanomas and 39 corresponding metastases were analysed for DNA content, nuclear morphometry, and proliferating cell nuclear antigen (PCNA). In 15 of 23 patients (65%) both primary and secondary tumours showed similar DNA patterns, whereas a disparity was found in the remaining eight patients (35%). The 23 primary tumours and groups of metastases (from different patients) located in skin, lymph nodes, and brain did not differ significantly in any of the variables investigated. Cox stepwise regression analysis indicated that a large variability (CV) of nuclear area in the first metastasis correlated with increased survival after recurrence (p = 0.039) as well as with survival (p = 0.031).