skin disorders
Tumors of the Nails
Introduction
Noncancerous (benign) and cancerous (malignant) tumors can affect the nail unit, causing a changes in nail texture and/or color ( Deformities, Dystrophies, and Discoloration of the Nails ). Many of these are tumors that originate in tissues around but not in the nail. Noncancerous tumors include myxoid cysts (benign, fluid-filled swellings), Pyogenic Granulomas , and glomus tumors. Cancerous tumors include Squamous Cell Carcinoma in Situ (an early form of skin cancer), A dark band in the nail may be the initial sign of malignant melanoma of the nail. Pigment cells of the nail-making tissue, known as the nail matrix, may become malignant and develop into a melanoma. A worrisome sign is known as Hutchinson sign. The Hutchinson sign is black, brown, or gray discoloration that extends to the area around the nail, such as the cuticle or nail fold (the fold of hard skin at the sides of the nail plate where the nail and the skin meet). This sign may mean there is melanoma in the nail bed (the soft tissue underneath the nail plate that attaches the nail to the finger). When this sign is present, doctors do a biopsy of the nail bed abnormality. Melanoma may also occur without the Hutchinson sign. 