Extraneural Soft Tissue Perineurioma: A Report of a Rare Case of Peripheral Nerve Sheath Tumor.

Extraneural perineuriomas are rare, benign soft tissue tumors arising from perineurial cells, which form the protective lining of peripheral nerves. These tumors are infrequently encountered in the foot, posing diagnostic challenges due to their rarity and non-specific clinical presentation. Here, we describe the case of a 45-year-old woman, who had a swelling over the right foot dorsum for four years for which an excision biopsy was done. Her histopathological variant and immunohistochemistry were consistent with extraneural perineurioma. This article aims to present a comprehensive review of extraneural perineuriomas, focusing on a case study involving the foot, and to discuss the clinical and histopathological characteristics, differential diagnosis, treatment options, and prognosis of this uncommon entity.