Objective  To evaluate the clinical effect and adverse reactions of radioactive seed interstitial brachytherapy combined with etoposide (EP) regimen concurrent chemoradiotherapy treatment for locally advanced non-small cell lung cancer.

  Methods  All 24 cases of locally advanced non-small cell lung cancer received three-dimensional conformal intensity modulated radiation therapy by using 6 MV X-ray to obtain 95% 60-66 Gy/30-33 F planning target volume.All cases received radiation therapy five times a week.EP regimen chemotherapy concurrent with radiotherapy was given to 24 patients.The therapy included VP-16, 60 mg/m²intravenous infusion for 1 d to 5 d, and DDP 50 mg/m²intravenous infusion on the 1st, 8th, and 28th therapy day.Chemotherapy with EP regimen was given for four cycles, in which two cycles were given during radiotherapy and the remaining cycles were completed after radiotherapy.The patients were reexamined three months after concurrent chemoradiotherapy was completed.Patients with residual tumor, confirmed via positron emission tomography/computed tomography, underwent¹²⁵I radioactive seed implantation interstitial brachytherapy to complement the dose of tumor.

  Results  The response rate was 83.3% (20/24);the local control rates of 3, 6, 9, 12, 18, and 24 months were 87.5% (21/24), 83.3% (20/24), 75.0% (18/24), 70.8% (17/24), 58.3% (14/24), and 50.0% (12/24).The median survival was 20.2 months.The one-year survival rate was 62.5%, and the two-year survival rate was 37.5%.The following main toxicities were observed: the incidence of radiation-induced lung injury was 25%;the incidence of radiation esophagitis was 33.3%;the incidence of grades Ⅰ to Ⅱ gastrointestinal reactions was 82.3%;the incidence of reducing neutropenia was 87.5%, in which the incidence of grades Ⅰ to Ⅱ was 75.0%, grade Ⅲ was 12.5%, and grade Ⅳ was 0%.

  Conclusion  EP regimen concurrent radiotherapy and chemotherapy combined with radioactive seed interstitial brachytherapy for locally advanced non-small cell lung cancer is effective and has few serious adverse reactions, thus making this approach worthy of promotion.