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The patient, a 63-year-old woman, presented with pain in the right peritrochanteric region that extended to the gluteus and lasted 3 months. Her movement was not limited, and she had no history of trauma, fever, or constitutional symptoms. During examination, pain was noted on digital compression of the trochanteric area, without signs of inflammation or limitation of active or passive mobilization of the coxofemoral joint. Results of radiographs of the lumbosacral spine and pelvis were normal. Axial STIR sequences (A) and T1 sequences with fat suppression after administration of gadolinium (B) were obtained on magnetic resonance imaging (MRI) of the right hip. The MRI showed a high signal intensity mass in the soft tissue between the greater trochanter (GT) and the ischial tuberosity (IT). STIR images showed high signal intensity in the central portion of the lesion (arrow in A) and peripheral and heterogeneous enhancement after administration of gadolinium on T1-weighted sequences (arrow in B). A biopsy was performed, and histologic analysis (C) revealed the presence of a schwannoma with degenerative features (ancient schwannoma), characterized by interstitial hyalinization, degenerative atypia, and cells with large and hyperchromatic nuclei. Schwannomas are benign and encapsulated tumors of the nerve sheath, found most commonly in the extremities, head, and neck ([1, 2]). The term “ancient schwannoma” is used to describe a tumor that has undergone degenerative changes; it is considered a rare condition and is most common in elderly patients ([1, 2]). Although extremely rare, the malignant transformation of ancient schwannoma has been described ([3]). Ancient schwannoma may be misdiagnosed as other types of tumors based on radiologic findings of cystic degeneration, such as malignant fibrous histiocytoma, malignant peripheral nerve sheath, and synovial sarcoma. Bursae presenting with thick walls and central cystic areas should also be considered in the differential diagnosis. Despite the rarity of these tumors, they should be considered in the differential diagnosis of soft tissue pain, as in the case reported herein.