The significance of blood flow in cutaneous malignant melanoma demonstrated by Doppler flowmetry.

The vascularity of malignant melanoma has been studied in 23 patients by Doppler ultrasonic frequency shift recordings. A 10 or 8 MHz directional Doppler probe was used and the signals were analysed on an Angioscan II spectrum analyser. No blood flow was detected in 7 primary melanomas each of thickness less than 0.75 mm and one recurrent subcutaneous nodule. Abnormal blood flow signals were detected in 8 primary melanomas--each of thickness greater than 1.2 mm--and in 7 skin nodules of secondary melanoma. Three tumours did not conform to the general pattern--one primary tumour 0.7 mm thick had abnormal blood flow signals whereas one primary lesion of 2 mm thickness and one secondary deposit were flow negative. Thus neovascularization corresponds in general to the cut-off point for good prognostic tumours, suggesting that it is a development of biological significance. This vascular pattern can be detected non-invasively by means of a Doppler probe and may have a prognostic importance, particularly with melanomas of the intermediate thickness range of 0.75-3.0 mm, where precise outcome cannot at present be predicted. The significance of an abnormal blood flow in one thin tumour remains to be determined from long-term follow-up.