Risk of Pneumonitis After Stereotactic Body Radiation Therapy in Patients With Previous Anatomic Lung Resection.
BACKGROUND
Stereotactic body radiation therapy (SBRT) has emerged as a standard treatment of early-stage, medically inoperable lung cancer. Limited data have evaluated the radiation pneumonitis (RP) risk with SBRT after previous anatomic lung resection (ALR). We assessed the incidence of RP and all pulmonary toxicity (PT) in patients who underwent lung SBRT after ALR and compared them with those of patients without previous ALR.


METHODS
We reviewed the medical records of 84 consecutively treated patients with stage T1-T2b non-small-cell lung cancer (NSCLC) treated with 88 courses of SBRT for 94 lung tumors from January 2007 to December 2014, including 17 patients with previous ALR. The rates of RP and all PT were compared between the patients with and without previous ALR.


RESULTS
At a median follow-up duration of 18.3 months (range, 1.8-85.6 months), the crude grade 2+ RP rate was 5.9% and 2.8% for patients with and without previous ALR, respectively (P = .51). The corresponding 2-year estimates of freedom from RP were 89% and 97% (P = .51). The crude rate of all grade 2+ PT was 11.8% and 2.8% for those with and without previous ALR (P = .11), with 2-year estimates of freedom from PT of 97% and 84% (P = .11), respectively. The 2 cohorts were well matched by the mean lung dose, percentage of lung volume receiving 20 Gy (P = .86), and prescribed dose (P = .75). The 2-year estimates of local control, cause-specific survival, and overall survival were similar between the 2 cohorts.


CONCLUSIONS
The observed rates of PT were low among all patients, with a trend toward increased grade 2 and 3 lung toxicity among patients with previous ALR. Previous ALR did not increase the risk of grade 4 and 5 RP, and SBRT appears safe and effective in this population.
Department of Radiation Oncology, University of California, Davis, Comprehensive Cancer Center, Sacramento, CA.
Jason T
JT
Hayes
Section of Thoracic Surgery, Department of Surgery, University of California, Davis, School of Medicine, Sacramento, CA.
Elizabeth A
EA
David
Division of Biostatistics, Department of Public Health Sciences, University of California, Davis, School of Medicine, Sacramento, CA.
LiHong
L
Qi
Department of Radiation Oncology, University of California, Los Angeles, School of Medicine, Los Angeles, CA.
Allen M
AM
Chen
Department of Radiation Oncology, University of California, Davis, Comprehensive Cancer Center, Sacramento, CA. Electronic address: megan.daly@ucdmc.ucdavis.edu.
Megan E
ME
Daly
D000368:Aged; D002289:Carcinoma, Non-Small-Cell Lung / Q000473:pathology / Q000601:surgery*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D015994:Incidence; D008175:Lung Neoplasms / Q000473:pathology / Q000601:surgery*; D008297:Male; D009367:Neoplasm Staging; D017564:Radiation Pneumonitis / Q000453:epidemiology / Q000209:etiology*; D016634:Radiosurgery / Q000009:adverse effects* / Q000379:methods; D012189:Retrospective Studies; D015996:Survival Rate
Lung resection; Non–small-cell lung cancer; Radiation pneumonitis; SBRT; Toxicity