Collecting duct carcinoma appearing as a hepatic hydatid cyst. A rare case report

Abstract

Background. Collecting duct carcinoma is located in the renal medulla and it originates from the collecting duct epithelium. It involves about 1% from all renal epithelial malignancies. Male patients are more exposed and the tumor localization shows a right sided predominance. It is characterized by aggressiveness and poor prognosis. Case report. We present a case of a middle age male patient who complained of right hypochondriac pain. The physical examination evidenced a large abdominal tumor formation in the right hypochondria and ultrasonography highlighted a mass, localized in the 8th segment of the right liver lobe. The primary diagnosis defined a hepatic hydatid cyst. A subsequent CT scan revealed a cystic structure of the right kidney, which presented Bosniak III type and measured 126x121x146 mm. Surgical treatment was initiated and intraoperatively a right kidney tumor was detected, due to which right nephrectomy was performed. The histopathological examination and the immunohistochemical profile established the final diagnosis of collecting duct carcinoma, with the tumor stage of pT3Nx. Regarding the patient's evolution, he was mobilized on the first postoperative day and was discharged after seven days. The patient did not receive any oncological treatment. 18 months following surgery the laboratory investigation values were within normal limits and any sign of relapse was excluded with ultrasonography. After 20 months the patient affirms that he is in good overall condition. Conclusions. As conclusion early diagnosis and surgical treatment can improve patient’s prognosis and disease-free survival. This work was supported by the Collegium Talentum 2019 Program of Hungary.