Clinical outcomes following image-guided stereotactic body radiation for pulmonary oligometastases
Daniel Kim, Mark M. Fuster, Sameerk. Nath, Anjali Bharne, WIlliam Read, Lyudmilla Bazhenova, William Y. Song, Arno J. Mundt and Ajay P. Sandhu
Background: The lung is a common site of extracranial metastases. Frameless Stereotactic Body Radiation Therapy (SBRT) is a promising new therapy for non surgically resectable neoplastic lung lesions used at our institution.
Materials and Methods: A retrospective study of 21 patients and 33 lesions treated with SBRT was done. Local control (LC), distant control (DC), progression-free survival (PFS) and overall survival (OS) were analyzed using the Kaplan-Meier method. Potential prognostic factors were analyzed using the log-rank test and Cox regression. Toxicities were also reported.
Results: Actuarial local control rates by lesions were 88% (95% confidence interval [CI], 77-99%) and 76% (95% CI, 59-92%) at 12-and 24-months, respectively. Actuarial local control rates by patients was 80% (95% CI, 62-98%) and 71% (95% CI, 43-100%) for 12- and 24-months, respectively. DC rates were 52% (95% CI 31-74%) and 38% (95% CI, 15-61%), at 12- and 24-months respectively. PFS rates were 52% (95%CI 31-74%) and 32% (95% CI 9-55%) at 12- and 24-months, respectively. Overall survival rates were 90% (95% CI 77-100%) and 78% (95% CI 59-97%) at 12- and 24-months, respectively. Single metastasis was associated with better PFS (p=0.023). No toxicities greater than CTCAE grade 3 were observed.
Conclusions: Frameless SBRT achieves acceptable control in pulmonary metastatic lesions with an excellent toxicity profile.
Keywords: Pulmonary metastases; oligometastases; stereotactic body radiotherapy (SBRT); frameless SBRT.