The initial diagnosis for lung cancer using isotope ratio

为了开发肺癌的检查方法，我们进行了各种试验。结果表明，该方法可测量大量的挥发性有机化合物，准确度高，且呼气量小，减轻了患者负担。作为呼气测试，不同食物的呼气几乎没有差异，呼气测试前禁止的食物和饮料的呼气时间也不长。吸烟者呼出的气体中苯的含量高于非吸烟者。吸烟6小时后，呼出物中苯含量逐渐降低。而且，吸薄荷香烟的呼出物中含有高浓度的苯和甲苯。利用热解吸系统，可以测量多种挥发性有机化合物的碳同位素，具有较高的精度和准确性。

For the development of the inspection method for lung cancer, we conducted various tests. As the results, the developed method can be measured lot of VOCs for high accuracy, and reduced a patient burden by small exhalation. As the exhalation test, there is almost no difference exhalation by different food and no long time by prohibited food and drinks before exhalation test. The exhalation for smokers included benzene than non-smoker. The benzene of exhalation was decreasing after smoking 6 hours. And, the exhalation for smoking menthol cigarettes included high level benzene and toluene. Using thermal desorption system, carbon isotope for many VOCs can be measured for high precision and accuracy.