Primary cutaneous melanoma in hidden sites is associated with thicker tumours - a study of 829 patients

The aim of this study was to determine if primary cutaneous melanomas in hi dden anatomical sites were associated with thicker tumours. Retrospective m edical data of 829 patients with melanomas diagnosed at our centre between January 1976 and July 1998 were recorded from our database. Three groups we re defined according to the anatomical site of the primary melanoma: (1) vi sible areas (group 1. 493 patients): (2) visible areas only to the patients or to their partners in privacy (group 2: 281 patients); and (3) hidden ar eas (group 3: 55 patients). Univariate analysis indicated that patients wit h melanoma in hidden regions presented significantly thicker tumours (media n for group 3: 2.25 versus 1.17 for group 1 and 1.42 for group 2). This gro up were also more commonly males (group 3: 58% men versus group 1: 38% and group 2. 51%), in a more advanced stage (metastatic disease at diagnosis in 16% of patients in group 3 versus 6% in groups 1 and 2) and at a more adva nced age (median group 3. 66 years versus group 1: 59 years and group 2: 51 years), than patients in the other two groups. The association between tum our thickness and body site remained statistically significant after a mult ivariate analysis. As a delay in diagnosis may be responsible for the thick er size of melanoma in the hidden areas, preventive programmes should stres s the importance of not forgetting these locations in self-examination and screening. Special attention should be given to educating elderly men. (C) 2001 Elsevier Science Ltd. All rights reserved.