title: False-negative fluorine-18 fluorodeoxyglucose positron emission tomography of a malignant peripheral nerve sheath tumor arising from a plexiform neurofibroma in the setting of neurofibromatosis type 1.
abstract: Development of malignant peripheral nerve sheath tumors (MPNSTs) is a recognized complication in patients with neurofibromatosis type 1 (NF1). Differentiating benign from malignant lesions can be a difficult clinical problem. Positron emission tomography (PET) is an established method for making this differentiation with a high degree of sensitivity and specificity. There are several reports showing that fluorine-18 fluorodeoxyglucose (FDG) PET is an effective imaging modality for detecting malignant transformation with a sensitivity nearing 100%. There are very few reports of false-negative 18F-FDG PET in a patient with an MPNST. This case report describes a woman with NF1 and a grade 3 MPNST and a negative PET scan. Identification of malignant transformation in NF is a significant clinical challenge. It is important to recognize the potential limitations of 18F-FDG PET in these patients.
authors.affiliation: Department of Radiology, Mayo Clinic, Rochester, MN 55905, USA.
authors.forename: Kameron R
authors.initials: KR
authors.lastname: Shahid
authors.forename: Kimberly K
authors.initials: KK
authors.lastname: Amrami
authors.forename: Robert J
authors.initials: RJ
authors.lastname: Esther
authors.forename: Val J
authors.initials: VJ
authors.lastname: Lowe
authors.forename: Robert J
authors.initials: RJ
authors.lastname: Spinner
mesh_terms: D000328:Adult; D003937:Diagnosis, Differential; D005188:False Negative Reactions; D005260:Female; D019788:Fluorodeoxyglucose F18; D006801:Humans; D008279:Magnetic Resonance Imaging; D018317:Nerve Sheath Neoplasms / Q000000981:diagnostic imaging* / Q000473:pathology; D018318:Neurofibroma, Plexiform / Q000000981:diagnostic imaging* / Q000473:pathology; D009456:Neurofibromatosis 1 / Q000150:complications* / Q000175:diagnosis / Q000000981:diagnostic imaging; D049268:Positron-Emission Tomography / Q000379:methods*; D019275:Radiopharmaceuticals
chemical_list: D019275:Radiopharmaceuticals; D019788:Fluorodeoxyglucose F18