Early Detection Of Transformation Of Plexiform Neurofibromas To Malignant Peripheral Nerve Sheath Tumors In Neurofibromatosis Type 1.

TPS10083 Background: Neurofibromatosis 1 (NF1), an autosomal dominant genetic disorder, is characterized by development of benign plexiform neurofibromas (PN) and malignant peripheral nerve sheath tumors (MPNST) that often develops from malignant transformation in a preexisting PN. Complete surgical resection is only curative treatment, making early detection of malignant transformation an important goal. A preliminary study by Meany et al [Pediatr Blood Cancer. 2013, 60(1): 59-64] using 18Fluoro-deoxy-glucose positron emission tomography (FDG-PET) to identify concerning lesions, described high FDG uptake in both malignant and benign PN.18F-3´-fluoro-3´-deoxy-L-thymidine (FLT) PET measures cell cycling and proliferation. We hypothesize that FLT-PET may be more sensitive and specific in the identification of malignancy. This pilot study in NF1 patients with lesions concerning for MPNST will evaluate 1) feasibility of FLT-PET 2) ability of FLT-PET to distinguish benign from malignant and 3) perform comprehe...