嘉義基督教醫院 外科部 泌尿科
Primary Renal Mucinous Cystadenoma Mimicking Hydronephrosis: A case report and literature review
Chang-Yu Tsai, Wei-Hong Lai, Yeong-Chin Jou, Cheng-Huang Shen, Chang-Te Lin, Ming-Chin Cheng
Divisions of Urology, Department of Surgery, Chia-Yi Christian Hospital
Mucinous cystadenoma of the pyelocaliceal system are considered extremely rare. In this article, we present a case of mucinous cystadenoma mimicking hydronephrosis, which also caused bilateral lower limbs edema and abnormal increment in waist circumference. Previous literatures associated with mucinous cystadenoma of the pyelocaliceal system will also be reviewed in this article.
This is a 69-year-old male with past history of gouty arthritis, who had suffered from bilateral lower limbs edema and abnormal increment in waist circumference for 3-months. He then came to our outpatient department for help. Abdominal ultra-sound and computed tomography (CT) scan revealed severe right hydronephrosis and hydroureter.
Right percutaneous nephrostomy (PCN) creation was performed and yellowish jelly-like material was drained out from the PCN which was negative for malignant cells. PCN was removed before discharge. During subsequent follow-ups, hydronephrosis and bilateral lower limbs edema did not improve. Cystic tumor was suspected and the comprehensive functional renal test revealed impaired right renal function (differential right renal function: 10%). Right laparoscopic nephrectomy was arranged. Intraoperative drainage was conducted and 3000c.c. yellowish jelly-like material was drained. The final pathologic report showed a resected polycystic and atrophic kidney which was occupied by the renal mucinous cystadenoma. The post-operative clinical course was smooth and the patient was discharged on postoperative day 5. There was also no recurrence noted during the 6-months follow-up period.
According to related literatures published, primary renal mucinous cystadenoma is uncommon. Due to the absence of typical presentation, these mucinous cystadenomas are usually discovered incidentally. In our case, the mucinous cystadenoma mimicked hydronephrosis, which led to bilateral lower limbs edema and abnormal increment in waist circumference. Preoperative imaging modalities such as abdominal CT and magnetic resonance imaging (MRI) are informative; however these modalities are insufficient in helping us to make an accurate pre-operative diagnosis of mucinous cystadenoma.
There is about 15-30% of mucinous cystadenoma developing into mucinous cystadenocarcinoma in various primary sites. The pathogenesis of mucinous cystadenoma was discussed, but have not yet been established nor fully understood. With surgical excision being the most prevalent treatment modality, both laparotomy and laparoscopic were reported. In our case, intraoperative drainage decreased the volume of the tumor, making laparoscopic technique feasible and safer.
This case reminds us that renal mucinous cystadenoma may mimic hydronephrosis, however majority reported were asymptomatic with no specific radiological feature. Intraoperative drainage may contribute to increased safety and convenience to both the surgeon and the patient.