Skin Cancer: Precancers

FP Essent. 2019 Jun;481:23-27.


Actinic keratoses (AKs) are common skin lesions caused by cumulative sun exposure. Rates of lesion progression to squamous cell carcinoma (SCC) have been reported to be between 0.025% and 16%, some lesions may regress. Atypical moles are melanocytic nevi that indicate a higher risk of melanoma and, on rare occasions, transform into malignant melanoma, particularly in patients with dysplastic nevus syndrome or familial atypical multiple mole-melanoma syndrome. Precancerous lesions can be identified by physical examination; diagnostic accuracy is enhanced by dermatoscopy. Biopsy is indicated when definitive diagnosis is deemed necessary for suspicious lesions. AKs can be managed with surgical methods, topical chemotherapeutic drugs, or photodynamic therapy. Complications of AKs include itching, pain, cosmetic concerns, and progression to SCC. Management of dysplastic nevi depends on the degree of atypia present. Lesions may be observed in cases of mild atypia with positive histologic margins but negative clinical margins. Dysplastic nevi with a high degree of atypia should be surgically excised or the patient should be referred to a dermatology subspecialist. Complications of atypical nevi include cosmetic concerns, recurrence, and rare progression to melanoma. Surveillance of precancerous lesions should include patient self-examination and regular follow-up skin examinations performed by the physician.

MeSH terms

  • Dysplastic Nevus Syndrome*
  • Humans
  • Melanoma*
  • Neoplasm Recurrence, Local
  • Nevus, Pigmented*
  • Skin Neoplasms*