Arthur J. Sober

Desmoplastic neurotropic melanoma. A clinicopathologic analysis of 28 cases

Background. Desmoplastic neurotropic melanoma (DNM) is a rare variant of malignant melanoma, the natural history and histogenesis of which still are being defined.

Precursors to skin cancer

Certain cutaneous lesions serve as both precursors of skin cancer and markers for increased risk. The solar or actinic keratosis serves such a role for the nonmelanoma (NMSC) forms of skin cancer (basal cell carcinoma and squamous cell carcinoma). Clinically, these keratoses manifest as rough, scaly, erythematous patches on chronically sun‐exposed surfaces. Conversion to squamous cell carcinoma in an individual lesion is uncommon and has been estimated at 1 per 1000 per year. Individuals with actinic keratoses have had sufficient chronic photodamage to produce skin cancer, and regular surveillance is recommended. The second precursor for invasive NMSC is Bowens disease (squamous cell carcinoma in situ). Invasion of the dermis results in frank squamous cell carcinoma. Some types of viral warts may develop into squamous cell carcinoma.