The Significance of Thin-Section CT in Quality Assurance and Control of Non-Small Cell Lung Cancer Therapy through 125I Seed Implantation / 天津医药

ABSTRACT

Objective To explore the clinical value of the thin-section CT scanning in all the steps of non-small cell lung cancer (NSCLC) therapy through 125I seed implantation. Methods In the 137 patients who were diagnosed with non-small cell cancer (NSCLC), the preoperative targets were delineated by CT scan, and the implantation plan was accom-plished according to treatment planning system (TPS); Intraoperative 125I seeds were implanted under the guidance of CT, then their positions were confirmed and corrected by CT scan layer-by-layer in real time;Post implantation dosimetry was validated also under the help of CT scan. If necessary, distribution and number of seeds should be adjusted to conform dose distribution under the principle of effectivity and micro-invasion;Follow-up and periodic evaluation should also be accom-plished by CT scan. Results Dose-volume histograms (DVHs) showed that the dose in line with the targets meet the re-quirement of prescription dose while the surrounding organs at risk were within the scope of their tolerance dose. Among 137 patients, implanted seeds number was the same with seeds number of TPS plan in 129 patients, and the coincidence rate was 94%. CT scan showed the local control efficient rate was 91.9%after 6 months. The 1-year and 2-year survival rates were 91.2%and 50.4%respectively. No serious operation-led complication was found during treatment. Conclusion The thin-section CT could be applied in all key steps of 125I seed implantation in NSCLC therapy, especially it is clinical significant and irreplaceable in quality assurance and control of seed implantation therapy.