[High dose rate brachytherapy: a potentially curative treatment for small invasive T1N0 endobronchial carcinoma and carcinoma in situ].

Introduction: High dose rate brachytherapy (HDR-BT) is an option for treatment of small invasive endobronchial carcinoma and carcinoma in situ. This retrospective study describes the results of 33 consecutive patients treated with curative intent and followed up for more than one year.

Methods: Between July 1994 and October 1999, 35 tumours were treated with HDR-BT alone using a standard protocol delivering 6 fractions of 5 Gy delivered across 1cm from the catheters over 3 to 6 weeks. In 31 patients, surgical treatment was ruled out because of histology (in situ carcinoma), history of pneumonectomy or significant co-morbidity. Two patients were treated for positive resection margins following pneumonectomy. All the tumours were Tis or T1 N0.

Results: The locations of tumours were: trachea - 2, main bronchus - 5, lobar - 20, and segmental - 8. Only one catheter was needed in 15 cases, 2 in 13 cases, 3 in 6 cases and 4 in 1 case. The median follow-up was 17 months (range, 5-53 months). The recurrence-free rate was 94.3% at 2 months and 86.2% at 6 months after the treatment. 15 patients (45.5%) developed local recurrence at a median time of 9 months. Three patients developed metastases. The 1-year and 2-year overall survival rate were 71.4% and 53.8% respectively and specific survival rates were 69.4% and 59%. One patient developed an acute pneumothorax, and late complications included 6 infections and 12 bronchial stenoses. There were no episodes of haemoptysis nor lethal complications.

Conclusions: With strict selection criteria, HDR-BT can be a curative treatment for early invasive or in situ endobronchial carcinoma without serious toxicity. It is therefore a good alternative treatment with curative intent for inoperable patients.