Nuclear DNA measurements of metastatic melanoma by a computerized digital imaging system.

To determine the extent of nuclear DNA abnormalities and their relationship with prognosis of stage II malignant melanoma, metastatic melanomas in lymphadenectomy specimens of 22 patients were studied by a computerized digital imaging system. The DNA ploidy pattern was aneuploid in 86% of the cases and tetraploid in the remaining 14%. In metastatic melanomas, there was a single clone in one third of patients and multiple clones in the remaining two thirds. Poor survival rate was associated with multiple clones and greater than 30% of mean coefficient of variation of DNA content. With tumor progression stem-cell lines often became heterogeneous with the development of multiple clones and widespread DNA values. These abnormalities, determined by nuclear DNA ploidy analysis, provide useful prognostic information.