Abstract：
OBJECTIVE: Most renal tumors merely displace nephrons while others can obliterate parenchyma in an invasive manner. Substantial parenchymal volume replacement (PVR) by renal cell carcinoma (RCC) may have oncologic implications; however, studies regarding PVR remain limited. Our objective was to evaluate the oncologic implications associated with PVR using improved methodology including more accurate and objective tools.
METHODS: A total of 1,222 patients with non-metastatic renal tumors managed with partial nephrectomy (PN) or radical nephrectomy (RN) at Cleveland Clinic (2011-2014) with necessary studies were retrospectively evaluated. Parenchymal volume analysis via semiautomated software was used to estimate split renal function and preoperative parenchymal volumes. Using the contralateral kidney as a control, %PVR was defined: (parenchymal volumecontralateral-parenchymal volumeipsilateral) normalized by parenchymal volumecontralateral x100%. PVR was determined preoperatively and not altered by management. Patients were grouped by degree of PVR: minimal (<5%, N = 566), modest (5%-25%, N = 414), and prominent (≥25%, N = 142). Kaplan-Meier was used to evaluate survival outcomes relative to degree of PVR. Multivariable Cox-regression models evaluated predictors of recurrence-free survival (RFS).
RESULTS: Of 1,122 patients, 801 (71%) were selected for PN and 321 (29%) for RN. Overall, median tumor size was 3.1 cm and 6.8 cm for PN and RN, respectively, and median follow-up was 8.6 years. Median %PVR was 15% (IQR = 6%-29%) for patients selected for RN and negligible for those selected for PN. %PVR correlated inversely with preoperative ipsilateral GFR (r = -0.49, P < 0.01) and directly with advanced pathologic stage, high tumor grade, clear cell histology, and sarcomatoid features (all P < 0.01). PVR≥25% associated with shortened recurrence-free, cancer-specific, and overall survival (all P < 0.01). Male sex, ≥pT3a, tumor grade 4, positive surgical margins, and PVR≥25% independently associated with reduced RFS (all P < 0.02).
CONCLUSIONS: Obliteration of normal parenchyma by RCC substantially impacts preoperative renal function and patient selection. Our data suggests that increased PVR is primarily driven by aggressive tumor characteristics and independently associates with reduced RFS, although further studies will be needed to substantiate our findings.
METHODS: A total of 1,222 patients with non-metastatic renal tumors managed with partial nephrectomy (PN) or radical nephrectomy (RN) at Cleveland Clinic (2011-2014) with necessary studies were retrospectively evaluated. Parenchymal volume analysis via semiautomated software was used to estimate split renal function and preoperative parenchymal volumes. Using the contralateral kidney as a control, %PVR was defined: (parenchymal volumecontralateral-parenchymal volumeipsilateral) normalized by parenchymal volumecontralateral x100%. PVR was determined preoperatively and not altered by management. Patients were grouped by degree of PVR: minimal (<5%, N = 566), modest (5%-25%, N = 414), and prominent (≥25%, N = 142). Kaplan-Meier was used to evaluate survival outcomes relative to degree of PVR. Multivariable Cox-regression models evaluated predictors of recurrence-free survival (RFS).
RESULTS: Of 1,122 patients, 801 (71%) were selected for PN and 321 (29%) for RN. Overall, median tumor size was 3.1 cm and 6.8 cm for PN and RN, respectively, and median follow-up was 8.6 years. Median %PVR was 15% (IQR = 6%-29%) for patients selected for RN and negligible for those selected for PN. %PVR correlated inversely with preoperative ipsilateral GFR (r = -0.49, P < 0.01) and directly with advanced pathologic stage, high tumor grade, clear cell histology, and sarcomatoid features (all P < 0.01). PVR≥25% associated with shortened recurrence-free, cancer-specific, and overall survival (all P < 0.01). Male sex, ≥pT3a, tumor grade 4, positive surgical margins, and PVR≥25% independently associated with reduced RFS (all P < 0.02).
CONCLUSIONS: Obliteration of normal parenchyma by RCC substantially impacts preoperative renal function and patient selection. Our data suggests that increased PVR is primarily driven by aggressive tumor characteristics and independently associates with reduced RFS, although further studies will be needed to substantiate our findings.
摘要：
目的：大多数肾肿瘤仅置换肾单位，而其他肾单位可以侵袭性方式切除实质。肾细胞癌（RCC）的实质实质体积置换（PVR）可能具有肿瘤学意义；然而，关于PVR的研究仍然有限。我们的目标是使用改进的方法，包括更准确和客观的工具，评估与PVR相关的肿瘤学意义。
方法：回顾性评估了在克利夫兰诊所（2011-2014年）接受部分肾切除术（PN）或根治性肾切除术（RN）的1,222例非转移性肾肿瘤患者，并进行了必要的研究。通过半自动软件进行的实质体积分析用于估计分裂的肾功能和术前实质体积。使用对侧肾脏作为对照，定义了％PVR：（实质体积-实质体积-实质体积）通过实质体积-实质体积-100%标准化。PVR在术前确定，未通过管理改变。患者按PVR程度分组：最小(<5%，N=566),适度(5%-25%，N=414),和突出(≥25%，N=142）。Kaplan-Meier用于评估与PVR程度相关的生存结果。多变量Cox回归模型评估了无复发生存率(RFS)的预测因子。
结果：在1,122名患者中，PN选择801例(71%)，RN选择321例(29%)。总的来说,PN和RN的中位肿瘤大小分别为3.1cm和6.8cm，分别,中位随访时间为8.6年.选择为RN的患者的PVR中位数为15％（IQR=6％-29％），而选择为PN的患者的PVR中位数为15％（IQR=6％-29％）。%PVR与术前同侧GFR呈负相关(r=-0.49,P<0.01),与晚期病理分期呈正相关,肿瘤分级高,透明细胞组织学，和肉瘤样特征（均P<0.01）。PVR≥25%与无复发缩短相关，癌症特异性，总生存期(均P<0.01)。男性,≥pT3a,肿瘤4级，手术切缘阳性，PVR≥25%与RFS降低独立相关(均P<0.02)。
结论：肾癌对正常实质的切除会显著影响术前肾功能和患者选择。我们的数据表明，PVR增加主要是由侵袭性肿瘤特征驱动的，并且与RFS减少独立相关。尽管需要进一步的研究来证实我们的发现.
方法：回顾性评估了在克利夫兰诊所（2011-2014年）接受部分肾切除术（PN）或根治性肾切除术（RN）的1,222例非转移性肾肿瘤患者，并进行了必要的研究。通过半自动软件进行的实质体积分析用于估计分裂的肾功能和术前实质体积。使用对侧肾脏作为对照，定义了％PVR：（实质体积-实质体积-实质体积）通过实质体积-实质体积-100%标准化。PVR在术前确定，未通过管理改变。患者按PVR程度分组：最小(<5%，N=566),适度(5%-25%，N=414),和突出(≥25%，N=142）。Kaplan-Meier用于评估与PVR程度相关的生存结果。多变量Cox回归模型评估了无复发生存率(RFS)的预测因子。
结果：在1,122名患者中，PN选择801例(71%)，RN选择321例(29%)。总的来说,PN和RN的中位肿瘤大小分别为3.1cm和6.8cm，分别,中位随访时间为8.6年.选择为RN的患者的PVR中位数为15％（IQR=6％-29％），而选择为PN的患者的PVR中位数为15％（IQR=6％-29％）。%PVR与术前同侧GFR呈负相关(r=-0.49,P<0.01),与晚期病理分期呈正相关,肿瘤分级高,透明细胞组织学，和肉瘤样特征（均P<0.01）。PVR≥25%与无复发缩短相关，癌症特异性，总生存期(均P<0.01)。男性,≥pT3a,肿瘤4级，手术切缘阳性，PVR≥25%与RFS降低独立相关(均P<0.02)。
结论：肾癌对正常实质的切除会显著影响术前肾功能和患者选择。我们的数据表明，PVR增加主要是由侵袭性肿瘤特征驱动的，并且与RFS减少独立相关。尽管需要进一步的研究来证实我们的发现.
