Multiple proliferating trichilemmal tumors in a middle-aged yellow man.

Proliferating trichilemmal tumor (PTT) is a rare but morphologically distinctive tumor. It usually occurs on the scalp of elderly women, characterized by frequent local recurrence. Some authors have recently proposed to classify PTT among the squamous cell carcinomas. We present the case of a 47-year-old yellow man with a 20-year history of multiple benign tumors in a number of anatomic areas. Based on their histological features, the tumors were diagnosed as PPTs. The case is unusual for the sex and age of the patient and the tumor locations. Moreover, this report illustrates a rare tumor which can be diagnostically challenging. The differentiation between a benign or malignant process in these lesions can sometimes be difficult. Careful clinical and histological assessment is necessary for an accurate diagnosis.