Derm Dx: A firm nodule with a positive skin crease sign

A 10-year-old boy presents with an asymptomatic firm nodule on his right cheek; it has enlarged slowly in size over the past year. The boy is in good health, without developmental or behavioral abnormality. On squeezing the lesion, a longitudinal crease is noted traversing the center of the growth. No similar lesions are noted elsewhere.