Detection of circulating tumor cells and microemboli in the blood of lung adenocarcinoma in situ patients case reports

Based on the pathological characteristics of lung adenocarcinoma in situ (AIS), conventional histopathological understanding suggests that non-small cell lung cancer (NSCLC) cells should not penetrate the basement membrane to enter systemic circulation. When cancer cells enter the blood circulation and form circulating tumor cells (CTCs) or even circulating tumor microemboli (CTM), they may trigger cancer metastasis. CASE PRESENTATION: In three AIS patients, we detected heterogeneous populations of CTCs and CTM in peripheral blood using the CTCBIOPSY® system-a finding that possibly contradicts established AIS pathomorphological criteria. Our findings suggest that CTCs/CTM may possess occult metastatic potential, indicating a dormant risk of micrometastasis even in AIS. Therefore, we believe that CTCs/CTM can serve as essential preoperative examination indicators for evaluating the prognosis of lung cancer patients and determining their treatment plans.