Trends in overall survival in 133 cases of balloon cell melanoma: An NCDB analysis.

Abstract

e21508 Background: Balloon cell melanoma (BCM) is a rare, malignant subtype of melanoma characterized by large, foamy melanocytes lacking pigmentation with a low overall 5-year survival rate of 37.5%. The incidence of melanoma is increasing at a greater rate than other types of cancer, but the cases of this subtype remain low. Demographic factors were analyzed via the National Cancer Database (NCDB) in an attempt to mitigate the knowledge gap in BCM diagnoses. The primary site at presentation and the effects of demographic factors on overall survival are described. Methods: A retrospective cohort analysis utilizing the NCDB from 2004 to 2020 included patients diagnosed with histologically confirmed BCM (N = 133). Socio-demographic factors (sex, age at diagnosis, race, facility type, and insurance type) were analyzed for frequency. A multivariate analysis of factors was performed on overall survival via the Kaplan–Meier Method (p = 0.05). Results: Since 2004, the number of cases diagnosed with BCM has steadily decreased (R2 = 0.204). The average age at diagnosis was 58.17 years (SD = 17.3). Most patients were male (63.9%), White (94.0%), treated at a non-academic center (56.4%), and had government insurance (96.1%). On multivariate analysis, age, race, and insurance type had statically significant effects on overall survival (p < 0.001). Patients that were older at diagnosis had poorer overall survival (p < 0.001, CI = [1.022 - 1.075]). Black patients were 4.6 times more likely than White patients to have suffered death (p < 0.001, CI = [23.586 - 450.230]). Patients without insurance were more likely to die than patients with government insurance (p < 0.001, CI = [0.026 - 0.229]). The average time from diagnosis until death was 143.1 months (SD = 8.0) with a 1-year and 5-year survival rate of 92.0% and 72.2%, respectively. Conclusions: This is the first study analyzing trends and demographic features relating to BCM in the NCDB. Due to the low survival rate of this cancer, understanding the risk factors affecting overall survival serve as a valuable clinical tool for prognostic evaluation. This database analysis suggests that the survival rate of BCM might be higher than previous literature suggests. The differences in BCM treatment on overall survival were not described in this study. Future research should aim to evaluate other prognostic factors, such as treatment, on survival.