Abstract
We herein report FDG-PET/CT findings of sarcomatous transformation in a patient with neurofibromatosis type 1 (NF-1). About 5% of patients with NF-1 develop sarcomatous transformation of a malignant peripheral nerve sheath tumor which arises from plexiform neurofibromas and is often associated with a poor prognosis. Morphologic imaging techniques such as Magnetic Resonance Imaging (MRI) and Computed Tomography (CT) are the standard methods to define the anatomic extent of the tumor, although tumor heterogeneity prevents reliable differentiation between benign and malignant lesions. The degree of fluoro-deoxyglucose (FDG) uptake correlates with histologic grade in neurogenic tumors in NF-1 patients. Our patient had a huge mass in the left gluteus area with a large nearly circular focus of increased FDG uptake in the tumor. The mass had a photopenic center. The maximum Standard Uptake Value (SUVmax) of this mass was 6.6. There was CT evidence of invasion of the left iliac wing, left acetabulum, and left superior pubic ramus; however there was no increased FDG uptake in these areas on the PET study. We surmised that the high FDG uptake indicated a high grade sarcoma, which was confirmed histologically. There was also a focal region of increased uptake in the L5 vertebral body, correlating with the CT hypodense lesion, with 2.9 SUVmax. FDG-PET/CT can identify sarcomatous change from benign neurogenic tumor with minimal misregistration, and can also detect metastatic disease. This case illustrates the importance of evaluating both metabolic and morphologic abnormalities to be able to formulate a proper treatment plan. This information can be obtained in a single session, using PET/CT.
Article PDF
Similar content being viewed by others
Explore related subjects
Discover the latest articles, news and stories from top researchers in related subjects.Avoid common mistakes on your manuscript.
References
Gutmann DH, Aylsworth A, Carey JC, Korf B, Marks J, Pyeritz RE, et al. The diagnostic evaluation and multi- disciplinary management of neurofibromatosis 1 and neurofibromatosis 2.JAMA 1997; 278: 51–57.
Lee J, Sohn SK, Ahn BC, Chun KA, Lee K, Kim CK. Sarcomatous transformation of neurofibromas. Comparative imaging with Ga-67, Tl-201, Tc-99m pentavalent DMSA and Tc-99m MIBI.Clin Nucl Med 1997; 22: 610–614.
Crim JR, Seeger LL, Yao L, Chandnani V, Eckardt JJ. Diagnosis of soft-tissue masses with MR imaging: can benign masses be differentiated from malignant ones?Radiology 1992; 185: 581–586.
Cardona S, Schwarzbach M, Hinz U, Dimitrakopoulou- Strauss A, Attigah N, Mechtersheimer G, et al. Evaluation of Fl 8-deoxyglucose positron emission tomography (FDG- PET) to assess the nature of neurogenic tumours.Eur J Surg Oncol 2003; 29: 536–541.
Ferner RE, Lucas JD, O’Doherty MJ, Hughes RA, Smith MA, Cronin BF, et al. Evaluation of (18)fluorodeoxy- glucose positron emission tomography ((18)FDG PET) in the detection of malignant peripheral nerve sheath tumours arising from within plexiform neurofibromas in neurofibromatosis 1.J Neurol Neurosurg Psychiatry 2000; 68: 353–357.
Solomon SB, Semih Dogan A, Nicol TL, Campbell JN, Pomper MG. Positron emission tomography in the detection and management of sarcomatous transformation in neurofibromatosis.Clin Nucl Med 2001; 26: 525–528.
Kendi TK, Erakar A, Yildiz HY, Saglik Y, Erekul S. Intraosseous malignant peripheral nerve sheath tumor with local recurrence, lung metastases and death.Skeletal Radiol 2004; 33: 223–225.
Author information
Authors and Affiliations
Rights and permissions
About this article
Cite this article
Otsuka, H., Graham, M.M., Kubo, A. et al. FDG-PET/CT findings of sarcomatous transformation in neurofibromatosis: a case report. Ann Nucl Med 19, 55–58 (2005). https://doi.org/10.1007/BF02986337
Received:
Accepted:
Issue Date:
DOI: https://doi.org/10.1007/BF02986337