The clinical analysis of chromophobe renal cell carcinoma / 中国医师进修杂志

ABSTRACT

Objective To explore the clinical features of chromophobe renal cell carcinoma (chRCC) in order to improve its diagnosis and treatment. Methods Clinical data of 8 patients with chRCC treated from July 2012 to February 2019 in the Second People′s Hospital of Lianyungang were retrospectively analyzed. There were 3 males and 5 females. Their age ranged from 34 to 71 years, with a mean age of (52.1 ± 11.2) years. All tumors were located unilaterally, with 3 cases in left kidney and 5 cases in right kidney. Five patients were asymptomatic and back pain occurred in other 3 patients. The maximum diameter of the tumor was 2.0 to 8.5 cm and the mean value was (5.6 ± 2.2) cm. Ultrasonography and CT scan were performed on all patients. Ultrasonography was mainly characterized by low echo renal mass with intact capsule and low blood flow signals. The CT appearances were typically well circumscribed and homogeneous solid mass, with mild enhanced. One case had calcification, 1 case had necrosis and cystic degeneration, and 1 case had central scar 1 case had significant enhancement. All patients underwent surgery. Five cases underwent retroperitoneal laparoscopic radical nephrectomy, 2 cases underwent open radical nephrectomy and 1 case underwent retroperitoneal laparoscopic partial nephrectomy. Results Postoperative pathologic findings confirmed the diagnosis of chRCC. The cross section of the tumors was grossly homogeneous, gray and yellow or gray and red. Immunohistochemical assay was positive of CK7 and CD117. The pathologic TNM stage of chRCC was as follows pT1aN0M0 in 2 cases, pT1bN0M0 in 2 cases, pT1bN0M1(with bone metastasis) in 1 case and pT2N0M0 in 3 cases. All cases were followed-up. The follow-up time was 3 to 79 months, and the mean time was (26.8 ± 24.1) months. One case with bone metastasis was treated with apatinib and had pulmonary metastasis 9 months after operation and died 19 months after operation. One case had pulmonary metastasis 24 months after operation and survived up to March 2019 refusing to accept targeted therapy. Other 6 patients were followed-up without local recurrence and metastasis. Conclusions chRCC is rare and its diagnosis mainly depends on pathology without obvious clinical and preoperative imaging presentation. Nephrectomy is the common treatment for chRCC and should follow the treatment principles of renal cell carcinoma, with a favorable prognosis owing to a relatively indolent clinical behavior.