Primary mucinous adenocarcinoma of the renal pelvis misdiagnosed as calculous pyonephrosis: a case report and literature review

Abstract

Primary mucinous adenocarcinoma of the renal pelvis is a rare malignant disease that is difficult to diagnose preoperatively. There are still no characteristic symptoms, radiological features, or standard treatment for this tumor with only ~100 cases reported. The prognosis is poor. We report a case of a 66-year-old man who presented with a 2-month history of fever and right waist pain. He was misdiagnosed with calculous pyonephrosis and underwent percutaneous nephrostomy (PCN) at a local hospital. Gelatinous material was drained via a PCN catheter. He was then transferred to our hospital. He had elevated CEA and CA19-9. We performed an open radical nephrectomy and found polypoid, gelatinous material and stones filling the renal pelvis. He was diagnosed with primary mucinous adenocarcinoma of the renal pelvis by pathology. He refused adjuvant chemotherapy and there was no sign of recurrence after one year of followup. By assessing a literature review of all of the cases reported since 2000, we recommend that careful history taking, serum tumor markers, and CT scans may improve the diagnostic accuracy rates and radical nephrectomy with total ureterectomy accompanied by adjuvant therapy may improve the prognosis.

Pyonephrosis Ultrasound and Computed Tomography Features: A Pictorial Review

“…PN is associated with factors that compromise host defense, including immunosuppression, renal failure, renal transplantation [ 1 , 2 ], and it is associated with local factors that compromise the urinary tract, such as congenital uropathy, neurogenic bladder, pregnancy, presence of foreign bodies such as calculi, indwelling catheters or other drainage devices, or endoscopic maneuvers, and it is frequently associated with the obstruction of the collecting system (renal calculus disease, RCD) [ 2 , 3 , 4 , 5 , 6 ]. PN has also been reported in patients with urinary obstruction from tumors, such as in transitional cell carcinoma [ 7 , 8 ]. Emerging evidence challenges the current paradigm that the bladder is a sterile microenvironment, and reveals that live bacteria are present in the bladder, even in “culture negative” patients [ 9 , 10 , 11 , 12 ].…”

Primary mucinous adenocarcinoma of the left renal pelvis with ectopic inferior vena cava and invasion of the left renal vein and the adjacent inferior vena cava: a case report

“…In addition, abdominal ultrasonography, intravenous pyelography, abdominal CT and other imaging examinations may not be able to accurately identify the tumor ( 12 ). Radiological findings of previously reported cases revealed that most of the patients presented with hydronephrosis, pyonephrosis and calculi, some patients presented with a mass or tumor, and a few patients presented with obstruction or stenosis of pelvis ureteric junction ( 1 ). The patient we reported presented with a huge mass, which was initially misdiagnosed as a renal cyst.…”

“…Primary mucinous adenocarcinoma of the renal pelvis lacks typical clinical manifestations. A recent article summarized the conditions of 30 patients reported in literatures since 2000 ( 1 ). Eleven cases presented single symptom of abdominal flank pain or discomfort, 3 cases presented single symptom of hematuria, and 2 cases presented single symptom of abdominal mass.…”

“…Primary mucinous adenocarcinoma of the kidney, lacking typical clinical manifestations and imaging features, is an especially rare malignancy and usually occurs in the renal pelvis ( 1 , 2 ). On the one hand, the patients may be easy to be missed due to having no symptoms in the early stage.…”

“…On the other hand, ultrasound examinations often show cystic masses with dark areas of anechoic liquid, which are easily misdiagnosed as renal cysts. Before operation, it is particularly difficult to obtain a definite diagnosis in clinical practice ( 1 ). The vast majority of patients are diagnosed according to pathological results of specimens after surgical treatment ( 2 , 3 ).…”