The scalp biopsy for hair loss and its interpretation

The diagnosis of alopecia is an area of dermatology that frequently relies on the close correlation of clinical and pathological features. Therefore,careful selection of the scalp biopsy site, optimal biopsy technique, and proper specimen processing followed by informed histological interpretation are essential steps in the successful evaluation of both cicatricial and noncicatricial alopecias. This review will serve as a primer for clinicians and pathologists alike wishing to optimize their approach to the scalp biopsy and interpretation of key noncicatricial and cicatricial alopecias.