Sentinel lymph node biopsy in pediatric and adolescent cutaneous melanoma patients.

BACKGROUND: The rarity of melanoma in young patients, particularly pediatric ones, has to date precluded any valid comparisons being made between young patients and adults undergoing sentinel lymph node biopsy (SLNB) for intermediate thickness localized melanoma. The present study takes advantage of the large Sydney Melanoma Unit (SMU) database to clarify this issue.

MATERIALS AND METHODS: Clinical and pathologic data on pediatric and adolescent AJCC Stage I and II cutaneous melanoma patients aged <20 years undergoing SLNB at the SMU between January 1993 and February 2008 were reviewed. SLNB positivity rates and outcomes in these patients were compared with adult SMU patients.

RESULTS: In 55 young patients, overall median tumor thickness was 1.7 mm (range, 0.6-5.2 mm) and overall SLNB positivity rate was 14 of 55 (25%), tumors tending to be thicker (median, 2.6 mm), and SLNB positivity rate higher (2 of 6; 33%) in patients aged <10 years. Of the 14 patients, 13 underwent immediate completion lymph node dissection (CLND); 2 patients had non-SLN metastases (15.4%). Only 0.7% of a total of 295 lymph nodes removed at CLND were involved with melanoma. In 14 SLNB-positive patients with follow-up data, 3 (21%) have died from melanoma after a median follow-up of 60 months, compared with 42% of 356 SLNB positive adults.

CONCLUSIONS: Although the SLNB positivity rate was higher in pediatric and adolescent melanoma patients than in adults (25% vs. 17%, respectively), non-SLN positivity and melanoma-specific death rates were low.