乳腺癌改良根治术后放疗中淋巴细胞减少对预后的影响

The influence of lymphopenia on prognosis in radiotherapy after mastectomy for breast cancer

目的:分析乳腺癌改良根治术后放疗中淋巴细胞减少与生存之间的关系,以及影响淋巴细胞减少的因素。方法:收集2017年01月至2022年08月我科乳腺癌改良根治术后辅助放疗患者,有完整放疗前、放疗期间以及放疗结束后外周血淋巴细胞计数,对淋巴细胞减少程度进行分级,采用Kaplan-Meier法比较0-2级淋巴细胞减少(G0-2)和3级淋巴细胞减少(G3)之间的无病生存(disease-free survival,DFS)与总生存(overall survival,OS),并用log-rank法检验。采用Logistic回归分析3级淋巴细胞减少的影响因素。结果:纳入132例患者,全组患者年龄(53.3±10.8)岁,中位放疗时间为5.0周。放疗过程中淋巴细胞减少程度为G0者27例(20.5%),G1者28例(21.2%),G2者56例(42.4%),G3者21例(15.9%),淋巴细胞数量随着放疗时间的进行持续下降,直至放疗第5周达到最低值。中位随访时间37.2个月,G0-2组中位DFS未达到,G3组中位DFS为40.6个月,G0-2组1年、3年、5年DFS分别为97.2%、90.7%、90.7%,G3组的1年、3年、5年DFS分别为81.0%、62.2%、41.5%(P<0.001)。术后放疗方式、肿瘤位置、BMI是影响放疗中淋巴细胞减少的独立危险因素。结论:乳腺癌改良根治术后放疗中G3级淋巴细胞减少的DFS率更低,术后放疗方式、肿瘤位置、BMI是影响放疗中淋巴细胞减少的独立危险因素。

Objective:To analyze the relationship between lymphopenia and survival in radiotherapy after mastectomy for breast cancer,and the factors affecting lymphopenia.Methods:The patients with breast cancer who received postoperative adjuvant radiotherapy after mastectomy in our department were collected from January 2017 to August 2022.The peripheral blood lymphocyte counts were obtained before,during,and at first follow-up after treatment.Lymphopenia was graded according to the degree of lymphocyte reduction.The Kaplan-Meier method was used to compare the disease-free survival(DFS) and overall survival(OS) between grade 0-2 lymphopenia(G0-2) and grade 3 lymphopenia(G3),and comparison between groups used the log-rank test.Logistic regression analysis was used to determine the predictive factors of grade 3 lymphopenia.Results:A total of 132 patients were enrolled.All patients were(53.3±10.8) years old,with a median radiotherapy time of 5.0 weeks.During treatment,the degree of lymphopenia were 27 cases(20.5%) in G0,28 cases(21.2%) in G1,56 cases(42.4%) in G2,and 21 cases(15.9%) in G3.Absolute lymphocyte count continued to decrease with the duration of radiotherapy until reaching the nadir at week 5.The median follow-up duration was 37.2 months.The median DFS of the G0-2 group was not achieved,the median DFS of the G3 group was 40.6 months.The 1-year,3-year,5-year DFS were 97.2%,90.7%,90.7% in the G0-2 group,compared to 81.0%,62.2%,41.5% in the G3 group,respectively( P < 0.001).Postoperative radiation method,tumor location,and body mass index( BMI) were independent risk factors of lymphopenia.Conclusion:G3 lymphopenia had poor disease-free survival in postoperative radiotherapy for breast cancer who received mastectomy.Postoperative radiation method,tumor location,and BMI are independent risk factors affecting lymphopenia during radiotherapy.