Abstract 765P
Background
Pediatric malignant melanoma (MM) is rare, accounting for 1-4% of all melanomas, but can be deadly. This study investigates diagnosis and survival rates in children with malignant melanoma, aiming to improve understanding and treatment of this cancer. The Breslow scale and Mitotic activity are compared as diagnostic criteria to provide updated evidence for medical professionals.
Methods
The study used the Surveillance, Epidemiology, and End Results (SEER) 8.4.3 software to analyze data on pediatric patients (aged 0-19) with cutaneous MM, according to ICD-0-3, from 2010-2020. Patients were categorized based on Breslow thickness, Mitotic activity, and therapy. High mitotic activity was defined as ≥ 2 mitoses/mm2 and high Breslow Classification as Breslow thickness >4mm. Survival analysis was done using Kaplan-Meier and long-rank test, with statistical analysis conducted using IBM SPSS Statistics 27.0.1.
Results
A total of 2035 patients (mean age, 14.5 ± 4.5 years; female 57%) were obtained. Most patients were Non-Hispanic White (82.8%). Overall, the median survival was 58 months, and the 1-year, 3-year, and 5-year relative survival were 97.4%, 94.2%, and 92.4% respectively. Patients with high mitotic activity showed low observed survival (95% CI: 1.16 -1.25, P < 0.005); meanwhile, high Breslow Classification showed no statistically significant observed survival (95%CI 1.8 -1.3 ; P >0.005). Patients treated with Gross excision (95%CI 2.36 -2.44, P < 0.005) showed greater 10-year survival than those treated with Local excision (95%CI 2.24 -2.4, P < 0.005). In contrast, Gross resection (including Mohs surgery) showed no statistically significant increase in survival when compared to Wide excision with >1cm margins (95%CI 2.35 -2.41 P > 0.005).
Conclusions
Diagnosing and managing pediatric Cutaneous MM are challenging for oncologists. Breslow Classification is important, but the mitotic rate is a crucial prognostic tool. While Mohs surgery and Gross resection are standard in adults, Wide excision is more effective in children, with local excision having the lowest survival rates.
Clinical trial identification
Legal entity responsible for the study
The authors.
Funding
Has not received any funding.
Disclosure
All authors have declared no conflicts of interest.