[18F]2-fluoro-2-deoxy-D-glucose positron emission tomography (FDG PET) as a diagnostic tool for neurofibromatosis 1 (NF1) associated malignant peripheral nerve sheath tumours (MPNSTs): a long-term clinical study.
BACKGROUND
Malignant peripheral nerve sheath tumours (MPNSTs) are difficult to detect in neurofibromatosis 1 (NF1) individuals. The purpose was to evaluate [(18)F]2-fluoro-2-deoxy-D-glucose positron emission tomography (FDG PET) and PET computed tomography (CT) as a diagnostic tool for MPNST in NF1 patients with symptomatic plexiform neurofibromas and to verify the diagnosis by pathology and clinical follow-up.


METHODS
NF1 individuals with symptomatic plexiform neurofibromas underwent clinical evaluation and magnetic resonance imaging. Qualitative FDG PET and PET CT associated with semi-quantitative maximum standard uptake value (SUVmax) assessed possible malignant change. Excision/biopsy verified the diagnosis when possible and clinical follow-up was undertaken in all patients.


RESULTS
In all, 116 lesions were detected in 105 patients aged 5-71 years, including 80 plexiform neurofibromas, five atypical neurofibromas, 29 MPNST and two other cancers. Biopsy confirmed the findings in 59 tumours and no MPNST was diagnosed on clinical follow-up of 23 lesions diagnosed as benign on FDG PET and PET CT. FDG PET and PET CT diagnosed NF1-associated tumours with a sensitivity of 0.89 [95% confidence interval (CI) 0.76-0.96] and a specificity of 0.95 (CI 0.88-0.98), but the SUVmax level did not predict tumour grade.


CONCLUSIONS
FDG PET and PET CT is a sensitive and specific diagnostic tool for NF1-associated MPNST. Other PET tracers will be required to solve the problem of predicting tumour grade.
Ferner
R E
RE
Department of Neurology, Guy's and St Thomas' NHS Foundation Trust, Kings College London, London, UK. rosalie.ferner@kcl.ac.uk
Golding
J F
JF
Smith
M
M
Calonje
E
E
Jan
W
W
Sanjayanathan
V
V
O'Doherty
M
M
D000293:Adolescent; D000328:Adult; D000367:Age Factors; D000368:Aged; D001707:Biopsy, Needle; D002648:Child; D002675:Child, Preschool; D015331:Cohort Studies; D005260:Female; D019788:Fluorodeoxyglucose F18; D005500:Follow-Up Studies; D006801:Humans; D007150:Immunohistochemistry; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D009367:Neoplasm Staging; D018317:Nerve Sheath Neoplasms / Q000000981:diagnostic imaging* / Q000473:pathology / Q000503:physiopathology; D018318:Neurofibroma, Plexiform / Q000000981:diagnostic imaging* / Q000473:pathology / Q000503:physiopathology; D009456:Neurofibromatosis 1 / Q000000981:diagnostic imaging* / Q000473:pathology / Q000503:physiopathology; D049268:Positron-Emission Tomography / Q000379:methods*; D011336:Probability; D018570:Risk Assessment; D012680:Sensitivity and Specificity; D012737:Sex Factors; D014057:Tomography, X-Ray Computed
D019788:Fluorodeoxyglucose F18