RESUMEN
We report a case of primary seminal vesicle spindle cell sarcoma of a 57-year-old man who underwent multiple surgical treatment. The first diagnosis of a local hospital was a right seminal vesicle cyst, so only laparoscopic decompression was performed. Postoperatively, the patient gradually developed lower abdominal discomfort, frequent and urgent urination, dysuria and constipation. Digital rectal examination palpated a heterogeneous mass. Magnetic resonance imaging showed a multilocular cystic mass of about 4.5 cm in diameter in the right seminal vesicle, which was diagnosed as a recurrent cyst. The patient underwent a second operation in our hospital, but the tumour could not be completely removed because of severe peripheral adhesions. The postoperative pathological diagnosis was seminal vesicle cystadenoma with spindle cell sarcoma. One month later, a computed tomography scan performed at another hospital showed that the mass had invaded the bladder and sigmoid colon. The pathological diagnosis of re-examination was spindle cell liposarcoma. After neoadjuvant chemotherapy, extended resection of the tumour was performed, and adjuvant chemotherapy was continued after surgery. The total duration of follow-up was 19 months and 3 months after the third surgery. The patient survived with no recurrence or metastasis.