Skip to Main Content




  • CAN and DN are clinicopathologic markers of patients at an increased risk for melanoma. Patients with CAN/DN should be screened regularly for melanoma.

  • CAN are not obligate precursors to melanoma, and they do not have to be removed—they may be clinically monitored for change.

  • The majority of melanomas are believed to arise de novo, and are not associated with a precursor nevus.

image Beginner Tips

  • A biopsy of a pigmented lesion is performed if there is a high level of suspicion for melanoma. Other reasons for biopsy may include irritation, cosmesis, or atypical lesions in areas difficult to self-monitor.

  • An excisional biopsy is the preferred method to remove any lesion concerning for melanoma to provide the most accurate diagnosis and smallest risk of recurrence.

image Expert Tips

  • Reexcisions need not always be performed in mildly and moderately DN with clear margins on the original biopsy.

  • Mildly DN with positive histologic margins and no clinical residual pigmentation can be safely observed.

image Don’t Forget!

  • Observation of moderately DN with positive histologic margins and no clinical residuum may be reasonable, but more data are needed.

  • Severely DN with positive histologic margins should be reexcised.

image Pitfalls and Cautions

  • While the morbidity of a biopsy should always be considered, there is no substitute for biopsy in cases where a true concern for evolving melanoma exists.

  • Serial photography has no impact on the development of melanoma unless the clinician has a low threshold for biopsy for any evolving CAN.

image Patient Education Points

  • Patients should be taught that all CAN do not evolve on to melanoma, and that they represent a marker of melanoma risk rather than a “precancer.”

  • Therefore, most CAN may be monitored clinically as long as there is no evolution and they appear similar to the patient’s other CAN.

image Billing Pearls

  • The decision of whether to code a shave as a biopsy or shave removal is based on the clinician’s intent. Even a deep, broad scoop shave, if performed to biopsy the lesion in question, should be coded as a biopsy.


One of the greatest challenges to dermatologists and primary care clinicians alike is the management of complex pigmented lesions. Subtlety of diagnosis, slow evolution over time, and presentation in a broad array of demographic groups all add to the difficulty in appropriately assessing and managing these complex lesions. Most importantly, inadequate management or imprecise evaluation may result in tragic consequences, as melanoma represents the fifth most common cancer overall in the United States and is responsible for the majority of cancer deaths among women in the 25- to 30-year age group.1 Moreover, the precipitous drop in 10-year survival as a result of delayed diagnosis—patients with lesions less than 1 mm thick have a survival rate of 88%, whereas ...

Pop-up div Successfully Displayed

This div only appears when the trigger link is hovered over. Otherwise it is hidden from view.