Risk for second primary cancers among pediatric and young adult melanoma survivors.

ABSTRACT

BACKGROUND/OBJECTIVES: Second primary cancers (SPCs) are a leading cause of morbidity and mortality among cancer survivors. In this study, we aimed to characterize the incidence of SPCs among pediatric and young adult survivors of CM. METHODS: Using the Surveillance, Epidemiology, and End Results Program data spanning 2000-2018, we calculated standardized incidence ratios (SIR) to assess SPC risk in all pediatric (0-18 years) and young adult (19-29 years) patients with a first primary cancer diagnosis of CM. RESULTS: Of 7,169 total CM survivors, 632 (8.82%) developed a SPC, corresponding to a 5-fold increased risk (standardized incidence ratio [SIR] 4.98; 95% confidence interval [CI] 4.60-5.38) compared to the general population. There was a highly elevated risk for second primary melanoma across all age groups (SIR 32.5; 95% CI 29.7-35.6), constituting the majority of SPC diagnoses (N = 485). Infants diagnosed with CM before 1 year of age had the highest risk for any SPC (SIR 164; 95% CI 19.8-592) and young adults diagnosed at 25-29 years had the lowest risk (SIR 4.64; 95% CI 4.19-5.13). SPC incidence was highest within the first year of CM diagnosis (SIR 27.5; 95% CI 23.7-31.6) and progressively decreased with time. CONCLUSIONS: Variation exists in the incidence and type of SPC according to age among pediatric and young adult survivors of CM.