CT, MRI, and ¹⁸F-FDG PET/CT findings of malignant peripheral nerve sheath tumor of the head and neck

Abstract

Background Malignant peripheral nerve sheath tumor (MPNST) is a highly malignant tumor and rarely occurs in the head and neck. Purpose To describe the imaging features of MPNST of the head and neck. Material and Methods We retrospectively analyzed computed tomography (CT; n = 14), magnetic resonance imaging (MRI; n = 16), and F-FDG PET/CT (n = 5) imaging features of 18 MPNSTs of the head and neck in 17 patients. Special attention was paid to determine the nerve of origin from which the tumor might have arisen. Results All lesions were well-defined (n = 3) or ill-defined (n = 15) masses (mean, 6.1 cm). Lesions were at various locations but most commonly the neck (n = 8), followed by the intracranial cavity (n = 3), paranasal sinus (n = 2), and orbit (n = 2). The nerve of origin was inferred for 11 lesions: seven in the neck, two in the orbit, one in the cerebellopontine angle, and one on the parietal scalp. Attenuation, signal intensity, and enhancement pattern of the lesions on CT and MRI were non-specific. Necrosis/hemorrhage/cystic change within the lesion was considered to be present on images in 13 and bone change in nine. OnF-FDG PET/CT images, all five lesions demonstrated various hypermetabolic foci with maximum standard uptake value (SUV) from 3.2 to 14.6 (mean, 7.16 ± 4.57). Conclusion MPNSTs can arise from various locations in the head and neck. Though non-specific, a mass with an ill-defined margin along the presumed course of the cranial nerves may aid the diagnosis of MPSNT in the head and neck.

Sellar surprises: a single-centre experience of unusual sellar masses

“…4B1, B2 and B3). In a recent series describing MRI features of 16 MPNST patients, Kim et al reported varying MRI features, none being specific for MPNSTs (26). Thus, in a sporadic setting, missing the pre-operative diagnosis of MPNST is common; however, most of the tumors in their series showed either moderate or marked contrast enhancement, as was seen in our case.…”

Cranial and Spinal Malignant Peripheral Nerve Sheath Tumor: A Pathological Enigma

“…Also, invasion of adjacent structures, destruction of surrounding bone by pressure, or frank destruction is seen in 20% of cases, and it favors the diagnosis of MPNST. 21 Demeheri et al reported that the minimum apparent diffusion coefficient is lower in malignant tumors than benign MPNSTs. 24 The dynamic contrast-enhanced imaging and MR spectroscopy are additional MR sequences that can help differentiate these tumors from their benign counterparts.…”

“…Out of these, only 17 cases have been intraparenchymal lesions, while others arise from one of the nerves, either cranial or spinal. 21 22 Although the epidemiological data are very minimal, few literature reviews suggest that the average age is 39 years, with a male-to-female ratio of 1.5:1. 23 In our short series, the average age of the cohort was 34.3 years, with a male to female ratio of 0.2:1.…”

“… 5 Size criteria can be challenging to apply in some CNS cases. Other features like ill-defined margins, invasion of adjacent structures with peritumoral edema, 24 intratumoral cystic/necrotic/hemorrhagic changes, 25 nodular morphology, or inhomogeneity, 26 and frequent intratumoral calcifications 21 can be helpful to differentiate malignant versus benign lesions. Also, invasion of adjacent structures, destruction of surrounding bone by pressure, or frank destruction is seen in 20% of cases, and it favors the diagnosis of MPNST.…”

First documented case of intracranial falcine malignant peripheral nerve sheath tumor: illustrative case

“…However, the former originates directly from brain parenchymal tissue, and it has no relationship with the cranial nerves. [13][14][15] Pathogenetically, MINSTs are supposed to originate from ectopic multipotential mesenchymal cells of the neural crest, which are displaced during embryogenesis. 16 Nevertheless, only a few cases have been reported in the literature, and lesions are commonly located in the cerebral hemispheres.…”