Clinical Significance Of EpCAM In Circulating Tumor Cells In The Peripheral Blood During Adjuvant Therapy For Postoperative Non-small Cell Lung Cancer Patients

Background: The lung cancer is one of the severest malignancies dangerous for human’s health, whose morbidity and mortality are both highly increasing in all countries. Non-small cell lung cancer(NSCLC) is the most common type of lung cancer, comprising about 85% of all lung cancer. Operative resection and postoperative adjuvant treatment are the best choice. The effect of adjuvant treatment depends on imaging tests. However, the patient was already in stage IV when recurrences or metastases were found by imaging tests. There are few successful treatment options for stage IV patients and the 5-year survival rate is less than 2%. Therefore, an early indicator on monitoring the therapeutic effects during adjuvant therapy for postoperative NSCLC patients is in need. Studies have showed that circulating tumor cells of peripheral blood is an important factor leading to disease progression and exacerbation, and could have diagnostic value in early stage of lung cancer. Therefore, we put forward hypothesis that Ep CAM in circulating tumor cells in the peripheral blood can be an early indicator on monitoring the therapeutic effects during adjuvant therapy for postoperative NSCLC patients.Methods: The method of Taq Man probe RTFQ-PCR used in the earlier period experiment has been applied in the present study to detect the epithelial cell adhesion molecule(Ep CAM) in postoperative circulating tumor cells of peripheral blood for NSCLC patients, with the imaging diagnosis of recurrence and metastasis as the endpoint. The purpose of this study is to observe the difference of the Ep CAM inpostoperative circulating tumor cells of peripheral blood between recurrence group and non-recurrence group and initially explore the relationship between Ep CAM in postoperative circulating tumor cells of peripheral blood and adjuvant therapy effects for postoperative NSCLC patients.Results: A total of 76 NSCLC patients in Beijing Chest Hospital from Jan. 2013 to Jun. 2014 were divided into recurrence group(n = 23) and non-recurrence group(n = 53). Ep CAM in circulating tumor cells in the peripheral blood of both group patients before the fourth chemotherapy treatment are 5269.73±2356.39 copies/2ml and 3625.51±1790.39 copies/2ml, which is statistical significance(P = 0.008). The average monitoring time of Ep CAM in postoperative circulating tumor cells of peripheral blood is 3.25 months. The average time of imaging diagnosis of recurrence and metastasis is 8.00±4.91 months. The result has statistical significance(P<0.0001). Although the result of Ep CAM in circulating tumor cells in the peripheral blood of both group patients before the fourth chemotherapy treatment has statistical significance, Ep CAM in circulating tumor cells in the peripheral blood of recurrence group during chemotherapy treatment is higher than non-recurrence group. What’s more, Ep CAM in circulating tumor cells in the peripheral blood of recurrence group is increasing gradually between the second and fourth chemotherapy treatment. Things are the opposite for the non-recurrence group.Conclusions: Ep CAM in circulating tumor cells in the peripheral blood can be a good early indicator on monitoring the therapeutic effects during adjuvant therapy for postoperative NSCLC patients.