LAUSR

Background To analyze the efficacy of computed tomography (CT)-guided implantation of 125I radioactive particles in treatment of early lung cancer. Methods Six patients were analyzed, including 4 squamous cell carcinoma, 1 adenocarcinoma, and 1 small cell lung cancer. TPS software was used to calculate the therapeutic dose amount of particles implanted, and the spacing and distribution of seeds in the target area and adjacent tissues. Under the guidance of CT, 20-55 particles were implanted at each site, with the total number of radioactive particles being 226, the particle spacing being 0.5-1.0 cm, and the implantation being performed in accordance with the principle of uniform implantation. The patients were each followed up with repeated pulmonary CT scans at 1, 3, 6, 12, 18, 24, 30 and 36 months after the procedure. In accordance with the response evaluation criteria in solid tumors (RECIST), the following definitions for responses were used: complete response (CR), partial response (PR), stable disease (SD), progressive disease (PD). Results There were 2 CRs and 4 PRs one month after procedure; six patients were followed up 3 months after procedure, including 2 CRs and 4 PRs; one patient was lost in follow-up, and 5 patients were followed up 6 months after procedure, including 3 CRs and 2 PRs; five patients were followed up 12 months after procedure, including 3 CRs, 1 PR and 1 PD. The single PD patient was again given CT-guided implantation of 125I radioactive particles for the treatment of recurrent lesions. The pulmonary CT was repeated 6 months after procedure, and the response was evaluated as SD. Four patients were followed up 18 months after procedure, including 3 CRs and 1 PR; one patient was lost in follow-up and 3 patients were followed up 24 months after the procedure with the response being evaluated as CR for all of them; one patient was followed up 36 months after procedure, and the response was evaluated as PD. During the follow-up, no serious complications occurred in any of the patients. Conclusions The preliminary clinical observation showed that 125I radioactive particle implantation was a safe, reliable and effective therapeutic method for early lung cancer.