Association of tumor differentiation and prognosis in patients with rectal cancer undergoing neoadjuvant chemoradiation therapy

肿瘤分化程度与行新辅助放化疗的直肠癌患者预后的关系

Background and objective:Neoadjuvant chemoradiation therapy(NCRT)followed by radical resection has been a common practice for patients with locally advanced rectal cancer.This study aimed to analyse the association of tumor differentiation and prognosis in rectal-cancer patients undergoing NCRT.Methods:Patients with locally advanced,non-mucinous rectal cancer who underwent NCRT followed by radical resection between 2007 and 2017 were identified from an electronic health record system at the Sixth Affiliated Hospital of Sun Yatsen University(Guangzhou,China).Multivariable logistic regression and multivariate Cox regression were performed to analyse the association of response to NCRT and survival with clinicopathological characteristics of all these patients.Results:We identified 325 patients(241 males and 84 females;mean age,54.4611.2 years)who underwent NCRT followed by radical resection,including 26(8.0%)with poorly-differentiated rectal cancer,182(56.0%)with moderately-differentiated cancer and 117(36.0%)with well differentiated cancer.Propensity score matching analysis and multivariable logistic regression analysis results showed that tumor differentiation was significantly associated with response to NCRT.In the poor differentiation and non-poor differentiation groups,the 3-year overall survival(OS)rates were 74.6 and 93.5%,respectively,whereas the 3-year local recurrence rates were 18.6 and 3.7%,respectively.Multivariable Cox regression analyses revealed that poor differentiation was an independent risk factor for local recurrence and OS.Conclusions:Among the patients with locally advanced,non-mucinous rectal cancer,the patients with poorlydifferentiated cancer who underwent NCRT had a worse response to NCRT and poorer prognosis than those with moderately-and well-differentiated diseases.

背景:新辅助放化疗+根治性切除术已成为局部进展期直肠癌的常规治疗。本研究旨在分析肿瘤分化程度与新辅助放化疗直肠癌患者预后的关系。方法:通过中山大学附属第六医院电子健康记录系统筛选出2007-2017年间行新辅助放化疗+根治性切除术的局部进展期非黏液腺癌病例。分别采用多因素逻辑回归模型和多因素Cox回归模型分析与新辅助放化疗的治疗反应和预后相关的临床病理因素。结果:共计325例患者[男性241例,女性84例;年龄(54.4611.2)岁]入组研究,其中26例(8.0%)为低分化腺癌,182例(56.0%)中分化腺癌,117例(36.0%)高分化腺癌。倾向评分匹配分析和多因素逻辑回归分析显示,肿瘤分化程度与新辅助放化疗治疗反应相关。低分化腺癌和非低分化腺癌患者3年总生存率分别为74.6%和93.5%,3年局部复发率分别为18.6%和3.7%。多因素Cox回归分析证实,低分化腺癌是局部复发和总体生存的独立危险因素。结论:在接受新辅助放化疗的局部进展期直肠非黏液腺癌患者中,低分化腺癌对新辅助放化疗的治疗反应及患者预后均劣于中高分化腺癌。