Re: Tumor Size Does Not Predict Risk of Metastatic Disease or Prognosis of Small Renal Cell Carcinomas

摘要

Expert's summary:In the multicentre study by Klatte et al, 1208 patients treated with radical nephrectomy (69%) or nephron-sparing surgery (NSS; 31%) for small solid renal tumours (SRTs) were analysed. Only 12% of these tumours were benign, whereas the majority (88%) were renal cell carcinomas (RCCs). Seventy-seven percent were incidentally detected. Of the RCCs, 7% (n = 72) had lymph node and/or distant metastases at the time of operation: 56 were N0M1, 8 were N+MO, 8 were N+M1. For the latter group, median survival time was 45 mo (range: 26-64 mo), corresponding to 1- and 5-yr cancer-specific survival rates of 76% and 42%, respectively. Median progression-free survival for metastatic RCC (mRCC) patients was 28 mo (range: 6-50 mo), and the 1- and 5-yr progression-free survival rates were 65% and 39%, respectively. The incidence of mRCC was independent of tumour size: 7%, 6%, 5%, and 8% of RCCs sized 0.1-1 cm, 1.1-2 cm, 2.1-3 cm, and 3.1-4 cm, respectively, had primary metastases (p = 0.322). On multivariate Cox regression analyses, Eastern Cooperative Oncology Group (ECOG) performance score, T stage, presence of distant metastases. and Fuhrman grade were independent predictors of cancer-specific survival, but not tumour size was not. Importantly, 5% of RCCs (n = 52) recurred and 3% (n = 28) of N0M0 patients died because of the disease. Cancer-specific survival rates for N0M0 RCC at 1- and 5-yr were 96% and 91%, respectively. Thus, there was a small but not insignificant risk of synchronous and metachronous metastatic disease and associated cancer death, even in small, nonmetastatic SRTs.