A proliferating trichilemmal tumor is an uncommon, benign, and well-circumscribed hair follicle tumor. It is also called proliferating pilar cyst of the scalp. The tumor has an unclear pathogenesis, but it is often derived from a pre-existing trichilemmal or pilar cyst and is more common in women. The tumor has a slow-growing nature and capacity to be malignant. A 55-year-old female was admitted to Kars Harakani Hospital Neurosurgery Department with a scalp lesion that was growing for 1 month and was infected. Although scalp lesions are frequently encountered in daily neurosurgical practice, proliferating trichilemmal cysts are quite a rare entity, and neurosurgeons should be aware of trichilemmal tumors during differential diagnosis.
Corresponding Author: Yakar F.