Semi-solid cultures of primary melanomas and their correlation with histopathological features.

The results of semi-solid cultures of fresh biopsy material from 86 primary human melanomas are reported. Detailed histological assessments by Professor McGovern were available for 80 of the 86 melanomas, and these were compared with the growth characteristics of each specimen. Significant correlations were found between growth in hypoxic semi-solid culture and tumour thickness and numbers of mitoses, and there was a suggestive association between growth and the shape of the lesion. Seventy-seven patients had Stage I disease, and follow-up data were available for 68 of these. Twenty-one patients had relapsed and 9 had died. Time to relapse was significantly shorter in patients whose primary tumour grew in culture and in patients with tumours thicker than 1.5 mm. These results show correlations between the biological behaviour of human melanoma, as assessed in vitro by culture, and the histological assessments previously reported. Growth in culture, tumour thickness and number of mitoses were interdependent variables, with growth and thickness predicting for time to relapse. Further studies will be needed to determine the relative risks attached to each of these.