Epidemiological trends and socioeconomic factors in malignant peripheral nerve sheath tumors with rhabdomyoblastic differentiation: A National Cancer Database study.
Authors: Yaye Fatou Diagne, William Brausch, Kat Chin, Isabel Langas, Peter T. Silberstein, Craig Heise, Beau Hsia
Journal: Journal of Clinical Oncology (2024)

e23562 Background: Malignant peripheral nerve sheath tumor with rhabdomyoblastic differentiation, also called a malignant triton tumor (MTT) is both a rare and aggressive form of cancer with both the features of peripheral nerve sheath tumors as well as rhabdomyoblasts with high recurrence rates. There is a higher risk of patients with neurofibromatosis type 1 (NF1) developing MTT. Radiation can be used to excise higher grade large MTT, however, chemotherapy still has no consensus on efficacy. Despite the rarity of MTT with rhabdomyoblastic differentiation, increased efforts to understand epidemiological trends could increase overall understanding of the malignancy. Methods: We extracted data from 50 patients diagnosed with MTT(ICD-9561-3) using the 2004-2020 National Cancer Database (NCDB) to perform a retrospective cohort analysis. We focused on various demographic factors including age, sex, race, Hispanic status, income status, educational status, insurance status, facility type and location, distance from facility, and Charleson-Deyo score using descriptive statistics. Regression analysis was used to identify incidence trends. Results: In our study of 50 patients diagnosed with MTT, a majority of the patients were male (62%), identified as White, and were of non-Spanish/non-Hispanic (90%) ethnicity. The average age at diagnosis was 49 years (SD = 20, range = 3-90) most and patients were treated in academic/research facilities (32%) or integrated network cancer programs (18%). Most patients (48%) had private insurance, with a significant number relying on government-funded programs (44%). The majority of patients (88%) underwent surgery as their primary treatment, with 30% having no residual tumor post-surgery. Additional treatments included radiation therapy (38%), chemotherapy (34%) and the most frequent primary site was the retroperitoneum (30%).The average survival time post-treatment was 35 months, with a survival rate of 43% at 2 years, 23% at 5 years, and a 15% at 10 years. Patients qualified for the top quartile of median housing income( $74,063 ≈). Conclusions: This study is the first analysis of patients with MTT, using the NCDB. It fills a gap in our understanding of this rare and aggressive disease. The majority of MTT patients were male, Caucasian, with an average age at diagnosis of 49 years, which supports previous case report descriptions. In addition, this study reveals the socio-economic factors associated with these patients who mostly earned a median income of $74,063 or more, were insured primarily by private insurance or managed programs (48%), and were treated predominantly in academic or research institutions (32%). It is necessary to continue research to further understand the influence of demographic and socio-economic factors on the diagnosis, treatments, and overall survival of patients with MTT.