Lung metastases treated with image-guided stereotactic body radiation therapy.

AIMS: To evaluate outcomes after treatment with image-guided stereotactic body radiation therapy (SBRT) using daily online cone beam computed tomography for malignancies metastatic to the lung.

MATERIALS AND

METHODS

Forty-seven lung metastases in 32 patients were treated with volumetrically guided SBRT. The median age was 62 years (21-87). Primaries included colorectal (n = 10), sarcoma (n = 4), head and neck (n = 4), melanoma (n = 3), bladder (n = 2), non-small cell lung cancer (n = 2), renal cell (n = 2), thymoma (n = 2), thyroid (n = 1), endometrial (n = 1) and oesophageal (n = 1). The number of lung metastases per patient ranged from one to three (68% single lesions). SBRT was prescribed to the edge of the target volume to a median dose of 60 Gy (48-65 Gy) in a median of four fractions (four to 10). Most lesions were treated using 12 Gy fractions (92%) to 48 or 60 Gy.

RESULTS

The median follow-up was 27.6 months (7.6-57.1 months). The 1, 2 and 3 year actuarial local control rates for all treated lesions were 97, 92 and 85%, respectively. Two patients with colorectal primaries (four lesions in total) had local failure. The median overall survival was 40 months. The 1, 2 and 3 year overall survival from the time of SBRT completion was 83, 76 and 63%, respectively. There were no grade 4 or 5 toxicities. Grade 3 toxicities (one instance of each) included pneumonitis, dyspnoea, cough, rib fracture and pain.

CONCLUSION

SBRT with daily online cone beam computed tomography for lung metastases achieved excellent local tumour control with low toxicity and encouraging 2 and 3 year survival.