Differentiation between neurofibromas and malignant peripheral nerve sheath tumors in neurofibromatosis 1 evaluated by MRI

• Published in: Journal of cancer research and clinical oncology 2009-07, Vol.135 (7), p.891-900
• Main Authors: Matsumine, Akihiko, Kusuzaki, K, Nakamura, T, Nakazora, S, Niimi, R, Matsubara, T, Uchida, K, Murata, T, Kudawara, I, Ueda, T, Naka, N, Araki, N, Maeda, M, Uchida, A
• Format: Article
• Language: English
• Subjects: Adolescent; Adult; Aged; Aged, 80 and over; Antineoplastic agents; Biological and medical sciences; Cancer Research; Diagnosis, Differential; Female; Gadolinium; Hematology; Humans; Internal Medicine; Magnetic Resonance Imaging - methods; Male; Medical diagnosis; Medical sciences; Medicine; Medicine & Public Health; Middle Aged; Nerve Sheath Neoplasms - diagnosis; Nervous system; Neurofibroma - diagnosis; Neurofibromatosis 1 - diagnosis; Neurology; NMR; Nuclear magnetic resonance; Oncology; Original Paper; Peripheral Nervous System Neoplasms - diagnosis; Pharmacology. Drug treatments; Radioisotopes; Tomography, Emission-Computed - methods; Tumors; Tumors of the nervous system. Phacomatoses; Young Adult
• ISSN: 0171-5216; 1432-1335
• DOI: 10.1007/s00432-008-0523-y

Purpose The imaging discrimination between neurofibroma (NF) and malignant peripheral nerve sheath tumor (MPNST) is clinically very important. The purpose of this study is to define the criteria for the differential diagnosis between NF and MPNST on MRI in neurofibromatosis 1 (NF1). Methods A total of 37 patients with NF1, 18 NFs and 19 MPNSTs were evaluated by MRI at 1.5 T. Magnetic resonance imaging (MRI) findings were compared using univariate and multivariate analyses. Results The MRI findings characteristic of MPNST (p < 0.05) were an irregular tumor shape (15/19 in MPNST vs. 5/18 in NF), unclear margin (13/19 in MPNST vs. 6/18 in NF), intra-tumoral lobulation (12/19 in MPNST vs. 3/18 in NF), presence of high signal-intensity area on T1-weighted images (T1WI) (12/19 in MPNST vs. 1/18 in NF), no target sign (0/19 in MPNST vs. 12/18 in NF), inhomogeneous enhancement on contract-enhanced T1WI (17/18 in MPNST vs. 9/16 in NF) and a lower rate of enhanced area (54% in MPNST vs. 87% in NF) were critical indicators to differentiate MPNST from NF. A multivariate analysis showed that intra-tumoral lobulation and the presence of a high signal-intensity area on T1WI were considered to be diagnostic indicators of MPNST. The sensitivity and specificity for these two items were 63.2, 83.3, 63.2 and 87.5%, respectively. Conclusion MRI shows features which were helpful for differentiating MPNST from NF.