Pediatric melanoma: results of a large cohort study and proposal for modified ABCD detection criteria for children.

BACKGROUND

Clinical and histopathologic features of childhood melanoma are poorly characterized. Atypical clinical presentations and ambiguous microscopic findings may contribute to diagnostic delays.

OBJECTIVES

We sought to determine whether conventional ABCDE melanoma detection criteria (Asymmetry, Border irregularity, Color variegation, Diameter >6 mm, Evolution [any morphologic or symptomatic change in the lesion]) adequately detects pediatric melanoma and to evaluate clinicopathologic and outcome differences between younger and older children.

METHODS

This was a retrospective study of children given the diagnosis of melanoma (N = 60) or ambiguous melanocytic tumors treated as melanoma (N = 10) before age 20 years from 1984 to 2009 at the University of California, San Francisco. Seventy patients were divided into 2 age groups: 0 to 10 years (N = 19, group A) and 11 to 19 years (N = 51, group B). Clinical, histopathologic, and outcomes data were collected. Main outcome measures were time from diagnosis to death and predictors of metastasis and death.

RESULTS

In all, 60% of group A and 40% of group B children did not present with conventional ABCDE criteria. Rather, amelanosis, bleeding, "bumps," uniform color, variable diameter, and de novo development were most common. Histopathological subtypes differed significantly between groups (P = .002). In all, 44% were histopathologically unclassifiable using current melanoma subtypes. Stage IIA disease or higher comprised 92% and 46% of groups A and B, respectively (P = .05). Ten patients died: 1 in group A and 9 in group B. Of these, 70% had amelanotic lesions, and 60% had at least 1 major risk factor. Breslow thickness predicted metastasis (adjusted odds ratio 12.8 [CI 1.4-115]).

LIMITATIONS

The retrospective design resulted in incomplete data capture.

CONCLUSION

Additional ABCD detection criteria (Amelanotic; Bleeding, Bump; Color uniformity; De novo, any Diameter) used together with conventional ABCDE criteria may facilitate earlier recognition and treatment of melanoma in children.