The clinicopathological characteristics and therapeutic analysis of renal oncocytoma / 中华泌尿外科杂志

ABSTRACT

Objective:To discuss the clinical and pathological features of the patients with renal oncocytoma.Methods:Making a retrospective analysis of the clinical data of 35 patients with renal oncocytoma who were admitted to the department of urology in the First affiliated Hospital of China Medical University from January 2013 to August 2020, discussing their clinical features, pathological characteristics, treatment and prognosis. The age range of the 35 patients was 35-79 years, with an average age of (59.0±11.3) years, there were 15 males and 20 females. The tumors of the 35 patients were unilateral, concluded 22 cases on the left side and 13 cases on the right side.Among the 35 patients, the tumors of 7 cases located in the upper pole, 14 in the middle pole, and 14 in the lower pole. At the time of admission, 5 patients complained with flank pain, 3 patients had gross hematuria, and the other patients were found during physical examination or examination due to other diseases. In the imaging examination, there were 33 cases of ultrasound data, including 18 cases of hypoechoic, 10 cases of hyperechoic, 3 cases of isoechoic and 2 cases of mixed echo. The data of CT were collected in 30 cases. The tumors showed isointense or slightly hypointense on plain scan, after enhancement, it showed low enhancement with clear boundary to the renal parenchyma and 12 patients had typical central stellate scar sign. All patients accepted surgical treatment, including 23 cases of retroperitoneal laparoscopic surgery and 12 cases of open surgery, but only 12 cases had partial nephrectomy.Results:The tumors were incised after the operation, the range of the tumors’diameter was 1.3-14.0 cm, with an average of (4.0±2.3) cm. The color of the cross-section was tawny in 14 cases, mahogany in 19 cases and 2 cases of other colors. The typical features of tumor cell under microscope were arranged in nests, alveolar or tubular shapes, the cells were round or polygonal.The cell size was uniform, the cytoplasm was rich in eosinophilic granules, the nuclei was deeply stained and the nucleoli was small. There are 9 indicators reach to 20 cases in immunohistochemical stain, and the positive rates of each indicator are respectively EMA 100.0%(23/23), E-cadherin 100.0%(20/20), CK 96.2%(25/26), CD117 95.5%(21/22), p504S(AMACR)35.0%(7/20), CD10 33.3%(9/27), CK7 31.0%(9/29), Vimentin 17.2%(5/29), Ki-67(0/28). Thirty-five patients were followed up after surgery, 4 patients were lost to follow-up, and the follow-up time of the other 31 patients ranged from 7 to 90 months, with an average of (46.9±25.0) months. All patients had a good prognosis without recurrence or metastasis. Among them, 3 patients had mild renal insufficiency in a short time after operation, and they have all recovered. Three patients with gross hematuria before the operation disappeared after the operation. In 5 patients with low back pain, only two patients felt significant improvement, and the other three still felt intermittent episodes of dull lumbar pain.Conclusions:Renal oncocytoma is a relatively rare benign tumor of the kidney. Because of the lack of effective diagnostic methods, it is difficult to differentiate from renal malignant tumors preoperatively. Pathological results are the golden standard for the diagnosis and differential diagnosis of renal oncocytoma. The main treatment of renal oncocytoma is surgery, and after surgery, the patient's prognosis is good, but renal oncocytoma has the possibility of recurrence and metastasis, regular follow-up and surveillance are still required.