Bilateral Renal Metastasis of an Inguinal Malignant Solitary Fibrous Tumor, 9 Years after Primary Surgical Treatment

Objective: To report the first case of a bilateral renal solitary fibrous tumor (SFT) as a metastasis of an inguinal malignant SFT. Clinical Presentation and Intervention: A 60-year-old male patient with a history of a right inguinal 7 × 8 cm soft tissue mass excision 9 years ago was referred to our clinic with abdominal pain. Both physical examination and chest X-ray were normal. Computed tomography revealed bilateral renal tumor. He was successfully treated with left partial and right radical nephrectomy. Histopathological examination showed a metastasis of the previous inguinal SFT. Conclusion: This case showed that although malignant SFT is extremely rare in the urogenital tract, this tumor should be included in the differential diagnosis when identified in the kidneys.