Central thoracic lesions treated with hypofractionated stereotactic body radiotherapy

Abstract

Purpose: To investigate the toxicity and outcome after moderately hypofractionated stereotactic body radiotherapy (SBRT) for central thoracic lesions.

Methods: Fifty-three patients undergoing 63 courses of SBRT for central thoracic lesions were retrospectively reviewed. Ninety-eight lesions received 30-63 Gy in 2.5-5.0 Gy fractions using the Novalis ExacTrac patient positioning platform.

Results: The 2-year lesion local control was 73%. Larger lesion volume was associated with poorer local control. The 2-year overall survival of patients with Stage I NSCLC, Stages II-III NSCLC and limited metastatic disease was 72%, 12% and 49%, respectively. There were four patient deaths from pulmonary causes, potentially grade 5 toxicities, though three had comorbid pulmonary conditions which may have contributed to the cause of death. One patient died from hemoptysis after undergoing two courses of SBRT to a mediastinal lesion. Most other deaths were attributable to metastatic progression.

Conclusions: Moderately hypofractionated SBRT to central thoracic lesions is effective with respect to local control and toxicity. Further dose escalation can provide an opportunity for better tumor control. Even with less aggressive dose fractionation, pulmonary deaths can occur, though it is difficult to ascertain the extent to which SBRT contributed to the death of patients with comorbid pulmonary conditions.