NF1 and undifferentiated pleomorphic sarcoma: Moreover, a recent cohort study established that patients with NF1 not only possessed significantly lower disease-specific survival (DSS) ratios for undifferentiated pleomorphic sarcomas, high-grade gliomas, MPNST, melanomas, or ovarian carcinomas in comparison to other tumors but also a lower age of occurrence for these neoplasms than in individuals without NF1 [14].