Clinical and histopathologic findings of basal cell carcinomas on completely covered anatomical sites of the body

Basal cell carcinoma (BCC) is the most common cancer type seen among the Caucasian population. Sun exposure may play a less important role in the causation of BCC in completely covered body sites than in sun-exposed skin. The aim of this study was to analyze in detail the BCCs that occur on completely covered anatomical sites. A total of 322 primary BCC cases was diagnosed. Of these, 44 were located on completely covered anatomical sites. Completely covered anatomical sites were classified as follows: trunk (including mammillae, excluding the neck), arms (excluding forearms and hands), legs (excluding feet), the perianal area and genitalia, and the buttocks and groin areas. Twenty-four lesions were of the superficial type, 14 lesions were of the nodular type, four lesions were of the infiltrative type, one lesion was of the morpheiform type, and one lesion was of the adenoid type. The most frequently reported symptom was itching. Forty-two percent of patients had no related symptoms. A close clinical check revealed 13 lesions which seemed to contain pigment. The preoperative diagnosis was based on clinical grounds and punch biopsies. Punch biopsies were performed on 10 cases which had been treated for a different diagnosis. The findings of our retrospective study showed that BCCs which occur on completely covered anatomical sites differ from those on sun-exposed skin. The clinical appearance of these sites with BCC may be similar to that which has other skin lesions. All physicians should bear in mind that BCC may occur not only in sun-exposed areas, but also in regions which are normally protected from ultraviolet radiation. © 2010 Springer-Verlag