Wang Zhixian, Zeng Xiaoyong, Chen Ruibao, Chen Zhiqiang
Department of Urology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei 430030, China,
Hubei Institute of Urology, Wuhan, China,
Cancer Manag Res. 2018 Nov 5;10:5339-5347. doi: 10.2147/CMAR.S176242. eCollection 2018.
To identify whether and which of pathological features of sarcomatoid differentiation (SD) in renal cell carcinoma (RCC) can be used as independent predictors associated with overall survival (OS).
After institutional review board approval, patients with a diagnosis of sarcomatoid RCC (sRCC), spindled RCC, or RCC with the presence of spindle cells between 2003 and 2017 were further selected and re-examined. The primary pathological features including histological subtypes, tumor necrosis, Ki-67 index of SD, and the percent of SD (%SD) were included into analysis. Histological subtypes were categorized into clear-cell RCC and nonclear-cell RCC. Ki-67 index of SD was confirmed by immunohistochemical staining. %SD was estimated through reviewing all of the tumor sections microscopically and then giving an approximate %SD within the entire tumor. The clinical relevant prognostic predictor's association with OS was analyzed within Cox proportional hazards regression models. Survival curves were generated using the Kaplan-Meier method, and OS differences were compared using the log-rank test.
A total of 2,089 consecutive patients of RCC were referred to our department, of whom 62 (3.0%) patients were identified with histological element of SD after re-examining the available slides of suspicious cases. Finally, 53 patients were included into survival analysis after excluding 9 patients without adequate information. Thirty-eight (71.7%) patients died at last follow-up. The median OS for all patients was 11.0 months from the date of surgery. In patients with clinical distant metastasis (cM), the median OS was only 3 compared with 21 months for patients with no clinical distant metastasis (cM). Tumor stage, status of clinical distant metastasis, Ki-67 index, and %SD were independent predictors of multivariate analysis in overall 53 patients. However, in the cohort of cM patients, we found that only %SD and Ki-67 index were two independent predictors of OS in multivariate analysis.
Patients with sRCC are associated with very poor prognosis. Ki-67 index of SD and %SD were identified as the two most important independent predictors particularly for nonmetastatic patients. The limitations of our study were also observed, and further studies are needed.
确定肾细胞癌（RCC）中肉瘤样分化（SD）的病理特征是否以及哪些可作为与总生存期（OS）相关的独立预测指标。
经机构审查委员会批准，选取2003年至2017年间诊断为肉瘤样肾细胞癌（sRCC）、梭形细胞肾细胞癌或伴有梭形细胞的肾细胞癌患者，并进行重新检查。分析的主要病理特征包括组织学亚型、肿瘤坏死、SD的Ki-67指数以及SD百分比（%SD）。组织学亚型分为透明细胞肾细胞癌和非透明细胞肾细胞癌。SD的Ki-67指数通过免疫组化染色确认。%SD通过显微镜检查所有肿瘤切片，然后给出整个肿瘤内的近似%SD来估计。在Cox比例风险回归模型中分析临床相关预后预测指标与OS的关联。采用Kaplan-Meier法生成生存曲线，并使用对数秩检验比较OS差异。
共有2089例连续的肾细胞癌患者转诊至我科，其中62例（3.0%）患者在重新检查可疑病例的可用切片后被确定有SD的组织学成分。最后，排除9例信息不充分的患者后，53例患者纳入生存分析。在最后一次随访时，38例（71.7%）患者死亡。所有患者从手术日期起的中位OS为11.0个月。有临床远处转移（cM）的患者中位OS仅为3个月，而无临床远处转移（cM）的患者为21个月。肿瘤分期、临床远处转移状态、Ki-67指数和%SD是53例患者多因素分析中的独立预测指标。然而，在cM患者队列中，我们发现在多因素分析中只有%SD和Ki-67指数是OS的两个独立预测指标。
sRCC患者预后很差。SD的Ki-67指数和%SD被确定为两个最重要的独立预测指标，特别是对于非转移性患者。我们也观察到了本研究的局限性，还需要进一步研究。
