Department of Urology, Mayo Clinic, Jacksonville, Florida 32224-1865, USA.
Urology. 2012 Jul;80(1):147-50. doi: 10.1016/j.urology.2012.04.013.
To examine the association between kidney size and renal cell carcinoma (RCC) death among patients with Stage pT1 clear cell RCC undergoing surgery.
We used a case-cohort design and evaluated 191 patients from our Nephrectomy Registry who had undergone open radical nephrectomy for unilateral, sporadic, Stage pT1N0/NxM0, noncystic clear cell RCC from 1989 to 2004. Of these, 47 patients died of RCC ("cases") and 144 patients were alive at the last follow-up visit or had died of other causes ("cohort"). Univariate and multivariate associations with RCC death were evaluated using weighted Cox regression analysis and summarized with hazard ratios and 95% confidence intervals.
The median kidney size was 12 cm. We observed a positive association between increasing kidney size and the risk of RCC death. A 1-cm increase in kidney size was associated with an 18% increased risk of RCC death, even after adjusting for tumor size, nuclear grade, and the presence of necrosis. After multivariate adjustment, those patients with a kidney size greater than the median were 95% more likely to die of RCC than those with a kidney size less than the median (hazard ratio 1.95, 95% confidence interval 1.00-3.81; P = .05). The limitations of our study included a lack of data on the 3-dimensional kidney volume and an inability to generalize to patients with larger tumors (ie, Stage pT2) or other RCC subtypes.
Our data suggest that kidney size is an independent predictor of survival for patients with Stage pT1 clear cell RCC. Future investigations are needed to confirm this finding and investigate this issue in larger, organ-confined tumors and other RCC subtypes.
研究接受手术的 pT1 期透明细胞肾细胞癌（RCC）患者的肾脏大小与 RCC 死亡之间的相关性。
我们使用病例-队列设计，评估了 191 名来自我们的肾切除术登记处的患者，这些患者于 1989 年至 2004 年期间因单侧、散发性、pT1N0/NxM0、非囊性透明细胞 RCC 接受了开放性根治性肾切除术。其中，47 例患者死于 RCC（“病例”），144 例患者在最后一次随访时仍存活或死于其他原因（“队列”）。使用加权 Cox 回归分析评估与 RCC 死亡相关的单变量和多变量关联，并总结风险比和 95%置信区间。
中位肾脏大小为 12cm。我们观察到肾脏大小的增加与 RCC 死亡风险之间存在正相关。肾脏大小每增加 1cm，RCC 死亡风险增加 18%，即使在调整肿瘤大小、核分级和坏死存在后也是如此。多变量调整后，肾脏大小大于中位数的患者死于 RCC 的可能性是肾脏大小小于中位数的患者的 95%（风险比 1.95，95%置信区间 1.00-3.81；P =.05）。我们研究的局限性包括缺乏关于 3 维肾脏体积的数据，以及无法将其推广到具有更大肿瘤（即 pT2 期）或其他 RCC 亚型的患者。
我们的数据表明，肾脏大小是 pT1 期透明细胞 RCC 患者生存的独立预测因素。需要进一步的研究来证实这一发现，并在更大的器官局限性肿瘤和其他 RCC 亚型中研究这一问题。
