In a review of 2296 patients with malignant melanoma, the overall incidence of a polypoid configuration was 21.5%. A markedly higher proportion of patients with polypoid melanoma than with dome-shaped melanoma first presented for melanoma treatment already with metastases (i.e. clinical stage II or III). In patients with localized disease, more men than women tended to present with polypoid lesions. The majority of these lesions were of the nodular histogenetic type, greater than 3.0 mm thick and ulcerated. When patients with polypoid and dome lesions were matched according to three known important prognostic determinants: sex of patient, the thickness of their primary lesion and whether their lesion showed microscopic evidence of ulceration, no consistent differences in prognosis were detected between patients with polypoid and dome lesions. Thus it appeared that the poor prognosis for patients with polypoid lesions was not attributable to the configuration of their lesion per se but primarily due to the fact that they were typically thick, ulcerated lesions.