直肠癌患者手术前后外周血髓源抑制性细胞比例及其与预后的关系

Relationship of preoperative and postoperative myeloid-derived suppressor cells percentage with the prognosis in rectal cancer patients

目的观察直肠癌患者手术前后外周血中髓源抑制性细胞（MDSC）比例的动态变化，并探讨MDSC比例与患者预后的关系。方法收集郑州大学附属肿瘤医院普通外科2009年1—12月间收治的64例Ⅰ～Ⅲ期直肠癌患者术前及术后21d的全血标本，通过流式细胞法检测MDSC比例．并分析其与患者预后的关系。结果术后21d，直肠癌患者MDSC比例较术前明显降低（P〈0．01），但发生局部复发或远处转移时，MDSC比例再次增高（均P〈0．01）并接近术前水平（均P〉0．05）。以中位数为界，术前MDSC比例较高组（大于3．78％）及术后MDSC比例较高组（大于2．11％）的5年总体生存率（分别为58．1％和62．1％）和5年无病生存率（分别为54．8％和58．6％）均显著低于术前及术后MDSC比例较低组（分别为87．9％和84．8％以及82．8％和80．0％，均P〈0．05）。多因素预后分析显示．术前MDSC比例为直肠癌患者总体生存的独立预后指标（HR=4．065，95％CI：1．026～16．108，P=0．04）。结论直肠癌患者术前外周血MDSC比例升高预后不良；MDSC比例的动态变化或可反映疾病进展情况。

Objective To observe the change of myeloid-derived suppressor cells （MDSCs） percentage in peripheral blood after operation in rectal cancer patients and to examine its association with the prognosis. Methods Blood samples of pre-operation and postoperative 21-day from 64 stage Ⅰ～Ⅲ rectal cancer patients who underwent surgery in Department of General Surgery, The Affiliated Cancer Hospital, Zhengzhou University between January and December 2009 were collected. MDSCs percentage was detected by flow cytometry. Its association with the prognosis of patients was analyzed. Results MDSCs percentage of postoperative 21-day decreased significantly compared with pre-operation （P〈0.01）. When local recurrence or distant metastasis presented, MDSCs percentage increased again （all P〈0.01 ） and reached the preoperative level（P〉0.05）. All the patients were further divided into two groups based on median MDSCs percentage. Patients with higher MDSCs percentage before operation （〉 3.78% ） and after operation （〉2.11% ） had significantly lower 5-year overall survival （OS） （58.1% and 62.1%） and 5-year disease-free survival （DFS） （54.8% and 58.6%） as compared to those with lower MDSCs percentage （5-year OS 87.9% and 84.8%; 5-year DFS 82.8% and 80.0%, all P〈0.05）. Multivariate analysis showed that preoperative MDSCs percentage was an independent prognostic factor of rectal cancer （HR：4.065, 95% CI：1.026 to 16.108, P=0.04）. Conclusions Preoperative increased MDSCs percentage may be an important predictor of poor OS in rectal cancer patients. Dynamic change of MDSCs percentage can reflect the disease development.