Digital monitoring by whole body photography and sequential digital dermoscopy detects thinner melanomas.

INTRODUCTION Population screening for melanoma remains controversial. There are no studies demonstrating that population screening increases survival. As prognosis of melanoma is directly related to Breslow thickness, a surrogate marker of survival is thickness of melanoma. The development of several self-referred, whole-body photography and sequential digital dermoscopy imaging services reflects the public's concern regarding melanoma.

AIM To assess the ability of one of these services to detect melanoma at an early, thin stage.

METHODS Demographic and histological details from 100 melanomas diagnosed through self-referred whole-body photography and sequential digital dermoscopy imaging service compared to those diagnosed through traditional methods from data held by the New Zealand Cancer Registry.

RESULTS There were 52 invasive and 48 in-situ melanomas: 90% superficial spreading type, 6% lentigo-maligna type and 4% nodular on histology. Forty-eight were diagnosed on first visit; the remainder by serial digital dermoscopy. Thirty-five percent of patients reported having had previous primary melanoma. In 60%, patients had been concerned by the lesion, the rest (40%) detected solely by screening. Patients diagnosed by whole-body photography and sequential digital dermoscopy screening had thinner melanomas compared to the Registry data: 69% <0.75 mm Breslow thickness compared to 52% (p=0.0216); only 1.9% thicker than 3 mm compared to 10.8% (p=0.067).

DISCUSSION Melanomas detected by self-referred, whole-body photography with sequential digital dermoscopy service are thinner than melanomas detected by traditional diagnostic methods. It remains to be determined whether earlier diagnosis results in improved survival.