Pediatric melanomas appear to be more progressive in adolescents than in young children, based on data from a retrospective study of 32 cases.
Few young children with melanoma die, despite a greater likelihood of thicker tumors, lymph node metastasis, and later diagnosis, which suggests that melanoma in young children may be biologically distinct from melanoma in adolescents, wrote Diana W. Bartenstein, of Harvard University Medical School, Boston, and her colleagues.
Overall, significantly more children than adolescents had spitzoid melanoma (50% vs. 10%, P = .01). In addition, children were more likely than adolescents to present with stage 3 or 4 cancer (58% vs. 25%) and with Clark level IV and V tumors (42% vs. 35%), although these differences were not significant. The median Breslow thickness of lesions was greater in children than in adolescents (3.5 mm vs. 1.5 mm) as was the median mitotic index (5 mitotic figures per mm2 vs. 2 mitotic figures per mm2) and children were more likely than adolescents to have neural invasion, but these differences were not significant either.