Abstract:

Objective To analyze the clinical and pathological characteristics of the mixed renal cell carcinoma （RCC） patient with co-existence of unilateral renal eosinophilic papillary renal cell carcinoma （OPRCC）and renal clear cell carcinoma （CCRCC）， and to improve the understandings of this disease. Methods The clinical data of one RCC patient with co-existence of OPRCC and CCRCC were retrospectively analyzed， and the diagnosis， treatment， and prognosis of the patient were analyzed in combination with the literature review. A 52-year-old male patient was admitted to the hospital due to a right renal mass detected by physical examination. The results of plain scan and enhancement CT of both kidneys showed space-occupying lesions of the right kidney， which was highly likely considered to be malignant. The laparoscopic partial nephrectomy was performed. Results The postoperative pathological results showed mixed RCC（lower pole of right kidney）.The results of immunohistochemical staining showed CK （AE/AE3） （partial +）， Vimentin （partial +）， EMA （partial +）， CK7 （+）， CD10 （+）， CAIX （partial +）， P504s （+）， PAX-8 （weak +）， TFE3 （－）， HMB45 （－）， MelanA （－）， SDHB （+）and Ki-67 （the positive rate was 2%）.The mixed RCC of the right kidney was diagnosed. The patient recovered quickly after operation and did not receive any adjuvant therapy. The CT examination results showed no local tumor recurrence and metastasis 3 months after operation， and no discomfort symptoms were found during the follow-up 6 months after operation. Conclusion The RCC patient with co-existence of OPRCC and CCRCC has no specific clinical manifestations， and the diagnosis mainly depends on the histopathological examination. Surgery is the first choice for the treatment；the malignant degree of the tumor is low， the progression is slow， the prognosis is good，and the long-term and close follow-up is still needed after operation.

Key words: Mixed renal cell carcinoma, Oncocytic papillary renal cell carcinoma, Clear cell renal cell carcinoma, Partial nephrectomy