Tumours of the skin adnexa: a case series with focus on multiple segmental forms.

Skin adnexal tumours (SAT) as a whole are rare tumours, and most of our current knowledge on SAT is from single case reports or small series focused on single histotypes. The purpose of this paper is to review a series of benign and malignant SAT diagnosed in a 20-year period.All consecutive cases of SAT diagnosed between January 1992 and Dicember 2011 were retrieved. All slides were reviewed and diagnosed according to currently accepted criteria.281 consecutive cases of SAT were found. The majority of cases (94.3%) were benign, the most frequent histotypes were eccrine spiradenoma, hidrocystoma, eccrine poroma, syringoma, sebaceous adenoma and trichofolliculoma. Benign SAT affected adult males more frequently (M/F = 153/112) (mean age 59 years). Recurrences were rare (2/265). Three cases of multiple segmental spiroadenoma were observed. Malignant SAT consituted only 5.7% of all cases comprising sebaceous carcinoma, extramammary Paget disease and apocrine carcinoma. There was a slight female predilection (M/F = 7/9) (mean age 72 years), although patients were older than those affected by benign SAT. All neoplasms were small and no recurrences were recorded.SAT are rare and most frequently benign. Correct diagnosis and complete surgical removal are important.