neoplasms of the nailbed neoplasms of the nailbed neoplasms of the nailbed may often present with paronychia, ingrown nail, onycholysis, pyogenic granuloma, nail-plate dystrophy, longitudinal erythronychia, bleeding, and discolorations.: 792 there are various benign and malignant neoplasms that may occur in or overlying the nail matrix and in the nailbed, and symptoms may include pain, itching, and throbbing.: 792 benign tumors of the nails include verruca, pyogenic granuloma, fibromas, nevus cell nevi, myxoid cysts, angiofibromas (koenen tumors), and epidermoid cysts.: 792 squamous cell carcinoma of the nailbed is uncommon, and often mistaken for a pyogenic granuloma initially.: 792 subungual melanoma is frequently diagnosed late in the course of growth.: 793