ABSTRACT
Objective To study clinical and histopathological features of high-risk small renal carcinoma and provide theoretical basis for the individualized treatment.Methods This retrospective study analyzed the clinical and histological data of 21 patients of high-risk small renal cell carcinomas which were highly aggressive or advanced stage, admitted from Jan 2000 to July 2015.There were 15 males and 6 females,and the average age was (61.5 ±7.1) years (ranged 27 to 75 years).The mean diameter of tumors was 3.3cm (ranged 2.0 to 4cm).The study mainly focused on pathological character and stage, Fuhrman grading, existence of perirenal tissue or vascular invasion, venous embolus and distant metastasis.Results Of all these 21 cases, 17 cases were clear cell carcinomas, 1 was papillary carcinoma, 2 were hybrid cellular tumor ( malignant rhabdoid tumor and sarcomatoid carcinoma) and 1 was sarcomatoid carcinoma. Among the 17 clear cell carcinoma cases, 12 were Fuhrman grade Ⅱ, 5 were grade Ⅲ and one was gradeⅣ.Tumor infiltrated renal vein or its branches and renal vein embolus were found in 7 cases.The tumor infiltrated perirenal or renal sinus fat were found in 11 cases.Synchronous lung and local lymph nodes metastasis were found in 3 patients respectively.Moreover, there was 1 case with metastasis to the brain (FuhrmanⅣ).The final clinical stage were T3a N0M0 in 14,T1a N1M0 in 3 and T1a N0M1 in 4 cases. Conclusions Small renal tumors are heterogeneous in its biological behavior and the minorities are aggressive with infringement of perirenal fat or simultaneous local lymph node or distant metastasis.When the tumor is greater than 3.0 cm in diameter and with high grade in Fuhrman classification, sarcomatoid carcinoma are more likely to be highly aggressive and advanced stage.