Exclusive high dose rate brachytherapy (HDR-BT) for early stage non-small cell lung carcinoma: Results of a retrospective study in 226 patients

7688 Objective: To evaluate efficacy and toxicity of HDR BT in non operable endobronchial carcinoma from a retrospective multicentric study. Patients and Methods: Criteria for selection: non small cell carcinoma accessible to fiberoptic bronchoscopy, no extrabronchial extension on CT, contraindication to surgery and external radiation therapy (ERT). Statistical analysis: survival curves calculated with the Kaplan-Meier method and compared with the Logrank test; Cox model to evaluate in uni and multivariate analysis the impact on survival and complications of these parameters: location of tumor: lobar or segmental vs main stem bronchus, previous ERT vs no, total dose:= 30 Gy vs less, dose per fraction:= 5 Gy vs more, number of catheter(s):1 vs = 2. Results: Between 1991 and 2006, 226 patients from 9 radiotherapy departments were included. Main characteristics of tumors: squamous-cell histology: 96%, stage Tis: 60, T1: 153, T2: 9, Tx 4; lobar or segmental location: 91%. 51 patients (22.5%) had received ERT for previous lung cancer(s). Characteristics of HDR BT were: total dose = 30 Gy: 70%, dose per fraction = 5 Gy: 66%, 1 catheter: 46%. Dose was prescribed at 1 cm from the radius. Mean follow-up was 30.4 months (9- 116). Histologic evaluation was performed at 3 months in 137 patients. 92% had a complete response. 128 patients were died: intercurrent disease 45, local failure 35, complications 13. Two and 5-year survival: overall: 57%, 29%; specific (death of lung cancer) 81%, 56%; local- relapse free (LRF) 68%, 50%. Toxicity included 1.3% pneumothorax, hemoptysis 6.6% (5% fatal), bronchitis 20%. In univariate analysis: overall, specific and LRF survival were better for lobar or segmental location vs main stem bronchus (p=0.0001), overall and specific survival were higher with no previous ERT (p=0.006). In multivariate analysis, lobar or segmental location was associated with improved overall (p=0.0001) and LRF (p=0.003) survival. LRF survival was better in patients treated with = 2 catheters (p=0.007). No factor influence frequency of complications. Conclusion: This large retrospective study confirmed that HDRBT is efficient and safe in medically inoperable patients particulary with lobar or segmental endobronchial carcinoma. No significant financial relationships to disclose.