BACKGROUND The association between natural killer (NK) cells and survival in colorectal cancer (CRC) patients remains controversial. This study aimed to clarify the prognostic value of peripheral blood NK cells in CRC patients. METHODS A total of 447 CRC patients who underwent radical surgery and chemotherapy were retrospectively analyzed. Cox regression analyses were used to identify independent prognostic indicators. Correlation between NK cell percentage and other clinicopathological features (gender, age, histological grade, tumor stage, immune cells, and inflammatory indicators) was analyzed. The prognostic values of the combinations of NK cell percentage and other clinicopathological features were also determined. RESULTS Multivariate Cox regression analysis revealed that NK cell percentage in the peripheral blood was an independent prognostic indicator in CRC patients. A higher percentage of NK cells indicated a longer survival time than a lower percentage. NK cell percentage was positively correlated to the T and B lymphocyte counts and negatively correlated to the patients' age and albumin levels. With an area of 0.741 under a receiver operating characteristic curve, NK cells have a moderate predictive value for 3rd-year survival in CRC. This area increased to 0.851 by combining NK cell percentage with the B lymphocyte count. Elderly patients and those at an advanced clinical stage presented a lower percentage of NK cells than younger patients and those at an early clinical stage. CONCLUSIONS This study demonstrated that NK cells in the blood were an independent predictor of survival in CRC patients, and the combined count of NK cells and B lymphocytes could increase the prognostic value.

中文翻译：

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外周血自然杀伤细胞在结直肠癌中的预后价值。

背景技术自然杀伤（NK）细胞与结直肠癌（CRC）患者的存活之间的关联仍存在争议。本研究旨在阐明外周血NK细胞在CRC患者中的预后价值。方法回顾性分析了447例接受根治性手术和化疗的CRC患者。使用Cox回归分析来确定独立的预后指标。分析了NK细胞百分比与其他临床病理特征（性别，年龄，组织学等级，肿瘤分期，免疫细胞和炎性指标）之间的相关性。还确定了NK细胞百分比和其他临床病理特征组合的预后价值。结果多变量Cox回归分析显示，外周血NK细胞百分比是CRC患者的独立预后指标。较高百分比的NK细胞表明存活时间比较低百分比的细胞更长。NK细胞百分比与T和B淋巴细胞计数呈正相关，与患者的年龄和白蛋白水平呈负相关。在受体工作特性曲线下的面积为0.741，NK细胞对于CRC的3年生存率具有中等预测价值。通过将NK细胞百分比与B淋巴细胞计数相结合，该区域增加到0.851。老年患者和临床晚期患者的NK细胞百分比低于年轻患者和临床早期患者。