Lipomatosis of the sciatic nerve: multimodal approach in diagnostics

Objective. To present a clinical case of atypically located nerve lipomatosis with traumatic injury in an adult patient’s medical history, and to demonstrate the current capabilities of ultrasound diagnostics in this pathology.

Materials and methods. A retrospective analysis of the patient’s medical history treated at the Peking University Third Hospital (China) was conducted.

Results. Nerve lipomatosis is a rare benign congenital peripheral nerve lesion. Involvement of the sciatic nerve trunk is exceptionally uncommon and may pose diagnostic challenges in differential diagnosis. Differential diagnostics is carried out with malignant neoplasms (liposarcoma, malignant neoplasm of the peripheral nerve sheaths) to avoid unjustifiably aggressive treatment.

Conclusion. The presented clinical case highlights the importance of an integrative approach based on a multidisciplinary analysis of clinical, morphological, and advanced medical imaging data for the accurate verification of rare peripheral nerve tumors with atypical localization.

1. Al Ghamdi YH, Alawad SH, Karem F, Alsaadi MJ. Fibrolipomatous hamartoma of the sciatic nerve: an atypical case report. Front Radiol. 2025;5:1-4. DOI: https://doi.org/10.3389/fradi.2025.1663742

2. Keppler-Noreuil KM, Rios JJ, Parker VE, Semple RK, Lindhurst MJ, Sapp JC, et al. PIK3CA-related overgrowth spectrum (PROS): diagnostic and testing eligibility criteria, differential diagnosis, and evaluation. Am J Med Genet A. 2015;167A(2):287-295. DOI: https://doi.org/10.1002/ajmg.a.36836

3. Canaud G, Hammill AM, Adams D, Vikkula M, Keppler-Noreuil KM. A review of mechanisms of disease across PIK3CA-related disorders with vascular manifestations. Orphanet J Rare Dis. 2021;16(1):1-10. DOI: https://doi.org/10.1186/s13023-021-01929-8

4. Gupta A, Geetha V, Monappa V, Bhat SS. Multiple neural fibrolipomas with macrodactyly. Indian J Dermatol. 2011;56(6):766-767. DOI: https://doi.org/10.4103/0019-5154.91851

5. 毛荣军, 杨克非, 王坚. 神经脂肪瘤病的临床病理学特征分析. 中华病理学杂志 2011;40(3):165-168.

6. Toms AP, Anastakis D, Bleakney RR, Marshall TJ. Lipofibromatous hamartoma of the upper extremity: a review of the radiologic findings for 15 patients. AJR Am J Roentgenol. 2006;186(3):805-811. DOI: https://doi.org/https://doi.org/10.2214/AJR.04.1717

7. Broski SM, Johnson GB, Howe BM, Nathan MA, Wenger DE, Spinner RJ, et al. Evaluation of (18)F-FDG PET and MRI in differentiating benign and malignant peripheral nerve sheath tumors. Skeletal Radiol. 2016;45(8):1097-1105. DOI: https://doi.org/10.1007/s00256-016-2394-7

8. Yao C, Zhou H, Dong Y, Alhaskawi A, Hasan Abdullah Ezzi S, Wang Z, et al. Malignant peripheral nerve sheath tumors: latest concepts in disease pathogenesis and clinical management. Cancers (Basel). 2023;15(4):1-19. DOI: https://doi.org/10.3390/cancers15041077

9. Marek T, Spinner RJ, Syal A, Wahood W, Mahan MA. Surgical treatment of lipomatosis of nerve: a systematic review. World Neurosurg. 2019;128:587-592.