The Developing Role of Molecular Imaging PET in Peripheral Nerve Sheath Tumors

A correct pretreatment classification is crucial to optimize diagnosis and to set the best care for patients with PNSTs. Because of the limitations related to the clinical presentation, the anatomical imaging (CT and MRI), and the invasive techniques, malignant degeneration is often identified late during the disease, compromising the potential for treatment. Therefore, the need for alternative techniques for detecting malignancy has led to the evaluation of the role of PET as a noninvasive and suitable in vivo imaging tool in different phases of the clinical management of PNSTs. Although the use of this imaging has not yet been fully determined, several scientific contributions demonstrated the potential value of 18F-FDG PET by using an accurate semiquantification of metabolic activity with SUV values and other parameters in the differential diagnosis between benign and malignant tissues, treatment planning, and follow-up. In addition, other PET radiopharmaceuticals (such as 18F Choline, 68Ga-PSMA, 68Ga-DOTATOC) have revealed their utility in assessing patients affected by different PNST, primarily reported in the literature as clinical cases or incidental findings. Even though most studies in this field lack large cohorts, include heterogeneous populations, and are still in the early stages, current data have proposed the promising role of PET imaging in the differential diagnosis of MPNST from benign lesions, improving the knowledge of these diseases.