Abstract：
Breath and fecal VOCs, among others, represent a new and encouraging clinical practice for the differential diagnosis of CRC. The purpose of our research was to identify VOCs present in exhaled air and feces of 20 HVs and 15 CRC patients. For collection of gas phase released from feces, emission microchambers were applied. Sorption tubes were used to enrich analytes for both breath and fecal samples. TD technique combined with GC-MS was used at the separation and identification step. The combination of statistical methods was used to evaluate the ability of VOCs to classify control group and CRC patients. Heptanoic acid, acetone, 2,6,10-trimethyldodecane, n-hexane, skatole, and dimethyl trisulfide are observed in elevated amounts in the patients group. The performance of diagnostic models on the tested data set was above 90%. This study is the first attempt to document the using of TD-GC-MS to analyze both breath and fecal samples to search for volatile biomarkers of CRC. A full evaluation of the results described herein requires further studies involving a larger number of samples. Moreover, it is particularly important to understand the metabolic pathways of substances postulated as tumor biomarkers.
摘要：
呼吸和粪便挥发性有机化合物（VOCs），其中,代表了结直肠癌（CRC）鉴别诊断的新的令人鼓舞的临床实践。我们研究的目的是确定20名健康志愿者（HV）和15名CRC患者的呼出空气和粪便中存在的VOC。为了收集粪便释放的气相，发射微室被应用。使用吸附管来富集呼吸和粪便样品的分析物。在分离和鉴定步骤中使用热脱附（TD）技术与气相色谱和质谱联用。采用统计学方法相结合的方法评价VOCs对对照组和CRC患者进行分类的能力。庚酸,丙酮,2,6,10-三甲基十二烷,正己烷,skatole,在患者组中观察到高含量的二甲基三硫。诊断模型在测试数据集上的表现在90%以上。这项研究是首次尝试使用TD-GC-MS分析呼吸和粪便样品以搜索CRC的挥发性生物标志物。对本文所述结果的全面评估需要涉及大量样品的进一步研究。此外，了解被假定为肿瘤生物标志物的物质的代谢途径尤为重要。
