This session began with a series of interactive case challenges and discussions on the optimal management congenital melanocytic nevi. Our panelists included Drs Hensin Tsao, Ashfaq Marghoob, Keith Flaherty, Whitney High, Ilona Frieden and Ken Tanabe.
Understanding the medical and surgical management of nevi and melanoma is extremely important for the practicing dermatologist. Nevi are benign tumors composed of nevo-melanocytes and can arrive during fetal development (congenital nevi) or after birth (acquired nevi). The presence of many acquired nevi and the presence of dysplastic nevi, independent of each other, are two of the strongest risk factors for melanoma.
Some of the key takeaway points from the case study presentations are noted below:
- The transformation of small congenital nevi to melanoma is rare and the vast majority of that risk is after puberty
- Melanomas tend to arise at the periphery of congenital nevi
- Family history is associated with an increased risk for melanoma, but not necessarily within the small nevus
- There is a period of time when most dermatologists would not prefer to perform surgery on children with CMN (18-months to three years)
- Multiple satellite lesions are associated with an increased risk for neuro-cutaneous melanocytosis (NCM) which is associated with a higher risk for melanoma in the central nervous system. The number of satellite lesions is more important than their location.
- Experts now acknowledge that the risk of developing melanoma is dependent on more than just size alone
- There is little published data for immunotherapy in pediatric populations with melanoma; however, immunotherapy is tolerated children with advanced disease; risk of autoimmune toxicities is there; treatment selection similar to that of young adults
Detection and Management of Melanoma
The goal for the optimal management of nevi is to find early melanoma while avoiding the removal benign nevi. This can be accomplished through periodic screening, dermoscopy, and the use of total body photography and/or digital dermatoscopic monitoring. If a lesion is found, the best method for biopsy is excisional biopsy. A broad deep shave biopsy that removes the entire lesion is acceptable. A punch biopsy may lead to sampling error if used to obtain tissue from larger lesions. ,
The panel presented several clinical pearls with regards to melanoma:
- Recognition of melanoma is based on a variety of factors
- Change in size and change in color are the most significant factors in detection of melanoma
- Primary prevention of melanoma is UV protection; secondary prevention includes removal of precursor lesions and early melanomas (surveillance)
- Sentinal lymph node biopsies are of prognostic value only and have not yet been shown to increase survival.
- Dermatopathology (biopsy, analysis, and report) plays an important role in the management of melanoma
- Relapse-free survival consistently improved with high-dose interferon
- Thin 1B melanomas can be aggressive and SLNBx should be considered on a case-by-case basis
- Knowing if a patient has BRAF mutation (found in 50% of melanomas) can affect therapeutic choice ie selection of a BRAF inhibitor and overall survival rate
- Ipilimumab has demonstrated improved survival in patients with metastatic melanoma however it can result in life threatening colitis.