Razi Journal of Medical Sciences

    Introduction: We report a case of sarcomatoid transitional cell carcinoma of urachus in a 53-year-old man with unusual and very rare pathology. Case Report: The patient was operated for BPH a year before his admission. He complained from abdominal pain and palpable tumoral mass in left rectus muscle for five months. At follow-up, abdominal ultrasonography showed one semi echo mass in left rectus muscle. Then, abdominal and pelvic CT scan with double contrast study revealed asymmetric enlargement of the left rectus muscle. The density of the muscle was in homogeneous central hypodensity region. Suggestive of chronic resorbing hematoma, abscess or rare tumoral lesion, cystescopy showed no space occupying lesion in mucosa of bladder, but external pressure was identified in dome of bladder. The patient was operated with possibility of soft tissue tumor of abdominal wall and with high probability suspect for sarcoma or desmoids tumor. Post-operative pathological diagnosis was sarcomatoid transitional cell carcinoma of urachus. Conclusion: In review of the literature we found only one case with TCC of urachus, and to our knowledge no case of sarcomatoid TCC of urachus has been reported before.