The incidence of malignant melanoma is increasing worldwide and patients are being diagnosed earlier with thinner primary lesions. Most patients with very thin melanoma (Breslow thickness < 0·76 mm) are cured by surgery but 2–18% relapse locally or with distant metastases.Objectives
The objective of this study was to establish potential new prognostic markers in very thin melanoma.Methods
We identified a group of subjects with relapsing very thin primary cutaneous melanoma and a matched control group who had not relapsed. We investigated the expression of p16, Helix pomatia agglutinin (HPA), CD95 and CD95 ligand (CD95L) by immunohistochemistry on paraffin-embedded tissue sections from the subject group, their subsequent metastases and the control group.Results
Reduced p16 expression was significantly associated with relapse in very thin melanoma (P = 0·0129). Loss of p16 expression was also found in 76% of metastases. There was no significant association between HPA, CD95 or CD95L expression and subsequent relapse.Conclusions
This work is the first to show a significant loss of p16 in relapsing very thin melanoma.