化疗后结直肠癌转移瘤钙化CT影像学表现与化疗反应之间的关系

目的 探究结直肠癌转移灶在联合西妥昔单抗靶向化疗后钙化的CT特征与其治疗疗效的关系。方法 回顾性分析2011年1月至2016年12月接受过联合西妥昔单抗靶向化疗且有完整资料的转移性结直肠癌钙化患者。两位影像科医生对患者治疗前后的肿瘤钙化的发生、钙化特征,以及治疗疗效评价进行独立评估。参照《实体肿瘤疗效评价标准(1.1版本)》 对患者的最佳疗效评价进行记录:(1)将完全缓解(complete response,CR)和部分缓解(partial response,PR)归为治疗有反应组,将疾病稳定(stable disease,SD)和疾病进展(progressive disease,PD)归为治疗无反应组;(2)对于疗效评价为SD的患者,由于无进展生存时间(progress free survival,PFS)较长的患者可以认为能从治疗中获益,因此根据PFS长短对其进行进一步分组,将PFS大于治疗有反应组中位PFS的患者与疗效评价为CR或PR的患者归为治疗获益组,余者归为治疗未获益组。对比分析患者转移瘤钙化的不同影像学特征(钙化形态、最大钙化密度、钙化密度-时间增长斜率)的差异。结果 在所有符合要求的111名患者中,出现肿瘤钙化的患者总计27例,共涉及30个部位,其中肝脏转移灶钙化患者19个(63.3%),淋巴结转移8个(26.7%),肺转移2个(6.7%),皮下转移1个(3.3%)。治疗有反应组12例,治疗无反应组15例;治疗获益组13例,治疗无获益组14例。治疗有反应组对比无反应组有较高的钙化密度-时间增长斜率,治疗获益组表现为钙化灶数量增加的比例(61.5%)较治疗无获益组(14.3%)高(P=0.018),最大钙化密度在各分组间差异均无统计学意义。肝转移瘤钙化灶均为无定形钙化,呈中心性钙化(占36.8%)、偏心性钙化(占36.8%)以及花环状钙化(占15.8%)和弥漫性钙化(占10.6%)。淋巴结转移灶可呈弥漫型(占75.0%), 以及曲线或壳状钙化(占25.0%),在各分组间差异无统计学意义。结论 在接受联合西妥昔单抗靶向化疗的晚期结直肠癌发生钙化的患者中,密度增长快、钙化数量的增加可能成为治疗疗效有效的影像学特征,最大钙化密度和钙化形态与疗效无明显关系。

Relationship between the CT features of colorectal cancer metastases calcification and tumor response to chemotherapy

Objective: To investigate the relationship between CT features of metastatic calcification and the response to chemotherapy in colorectal cancer metastases.Methods: A total of 27 patients with 30 sites of calcified metastases who underwent chemotherapy combined with targeted therapy (cetuximab) between January 2011 and December 2016 comprised this retrospective study population. Two radiologists independently evaluated the occurrence of tumor calcification before and after treatment, and evaluated the tumor response after therapy. According to the response evaluation criteria in solid tumors (version 1.1), the best curative effect evaluation of the patients was recorded. The patients were divided into groups as below: (1) Patients who showed complete response (CR) and partial response (PR) were assigned to the response group, and the stable disease (SD) and progressive disease (PD) were assigned to the non-response group. (2) Patients showed CR or PR, or patients showed SD with longer progress free survival (PFS) were assigned to the benefit group, and the remaining patients were assigned to the no benefit group. The difference of different imaging calcification features (morphology, maximum density, and density-time slope) were analyzed.Results: The most common site of metastases calcification was liver (63.3%), followed by lymph nodes (26.7%). There were 12 cases in the response group, 15 cases in the non-response group; and 13 cases in the benefit group, 14 cases in the no benefit group. The density time growth slope was higher in the response group when compared with the non-response group (P=0.025). The proportion of thhe patients with increased number of calcified foci in the benefit group (61.5%) was higher than that in the no benefit group (14.3%), P=0.018. There was no significant difference in the maximum density between the groups. The calcification of liver metastases were all amorphous calcification, with central calcification (36.8%), eccentric calcification (36.8%), garland calcification (15.8%) and diffuse calcification (10.6%). The lymph node metastases could be diffuse (75.0%), and curve or egg-shell calcification (25.0%). There was no statistical difference between the groups.Conclusion: In patients with advanced colorectal cancer metastases treated with cetu-ximab combined chemotherapy, rapid growth of calcification density and increased calcification number may be valuable imaging features of therapeutic efficacy. The maximal calcification density and morphology of calcification are not related to the therapeutic efficacy.