Primary radiotherapy with endobronchial high-dose-rate brachytherapy boost for inoperable lung cancer: long-term results.

BACKGROUND: To retrospectively evaluate the outcome of patients with inoperable non-small-cell lung cancer treated with primary external beam radiotherapy combined with high-dose-rate endobronchial brachytherapy boost.

PATIENTS AND METHODS: Between 1988 and 2005, 35 patients with non-small-cell lung cancer (stage I-III) ineligible for surgical resection and/or chemotherapy, were primarily treated with external beam radiotherapy with a median total dose of 50 Gy (range, 46-60). A median of 3 fractions high-dose-rate endobronchial brachytherapy was applied as a boost after external beam radiotherapy, the median total dose was 15 Gy (range, 8-20). High-dose-rate endobronchial brachytherapy was carried out with iridium-192 sources (370 GBq) and prescribed to 1 cm distance from the source axis.

RESULTS: With a median follow-up of 26 months from the first fraction of high-dose-rate endobronchial brachytherapy, the 1-, 2- and 5-year overall (local progression-free) survival rates were 76% (76%), 61% (57%) and 28% (42%), respectively. Complete or partial remission rates 6 to 8 weeks after treatment were 57% and 17%, respectively. Significant prognostic favorable factors were a complete remission 6-8 weeks after treatment and a negative nodal status. In patients without mediastinal node involvement, a long-term local control could be achieved with 56% 5-year local progression-free survival. Common Toxicity Criteria grade 3 toxicities were hemoptysis (n = 2) and necrosis (n = 1). One fatal hemoptysis occurred in combination with a local tumor recurrence.

CONCLUSIONS: The combination of external beam radiotherapy with high-dose-rate endobronchial brachytherapy boost is an effective primary treatment with acceptable toxicity in patients with non-small-cell lung cancer ineligible for surgical resection and/or chemotherapy.