FGFR3 and seborrheic keratosis: FGFR3 mutations may lead to a wide spectrum of disorders ranging from skeletal dysplasias (hypochondroplasia, achondroplasia, and thanatophoric dysplasia), benign skin tumors (epidermal nevi, seborrheic keratosis, and acanthosis nigricans), and epithelial malignancies (multiple myeloma, prostate and bladder carcinoma, and seminoma) [2].