Unusual presentation of pilomatricoma: A case report and comprehensive review of the literature.

Pilomatricoma is a benign proliferative lesion of skin appendages that often affects the head, upper limbs, and lower limbs. The clinical appearance of the lesions is that of asymptomatic nodules measuring less than 3 cm. pathologically, these skin lesions show the presence of basaloid cell islands, eosinophilic cytoplasmic cells without nuclei, as well as hemorrhage and calcification. In this study, we present the case of an 8-year-old girl with a 5 × 5 cm skin lesion on the forearm, which lacked the typical firmness associated with pilomatricoma lesions during examination. After biopsy, the lesion was confirmed to be pilomatricoma. Furthermore, we have reviewed studies documenting pilomatricoma lesions with atypical clinical features. Based on reports of different clinical manifestations of pilomatricoma in these studies, we suggest that the clinical diagnosis of pilomatricoma should not be limited to the typical presentation of these lesions. In cases where the lesions exceed 3 cm in size, display cystic characteristics, are painful, or resemble keloids, consideration should also be given to the possibility of pilomatricoma.