Chest Wall Toxicity after Stereotactic Radiation in Early Lung Cancer: A Systematic Review.

Background: Radiation-induced chest wall pain (CWP) and rib fracture (RF) are late adverse effects after stereotactic body radiation therapy (SBRT) for stage i non-small-cell lung cancer (NSCLC); however, the literature about their incidence and risk factors shows variability. We performed a systematic review to determine the pooled incidence of CWP and RF in the relevant population. Methods: A literature search using the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines considered English publications in MEDLINE and EMBASE from January 1996 to August 2017. Abstracts were screened, followed by full-text review and data extraction. Results: The database searches identified 547 records. Twenty-eight publications comprising 3892 patients met the inclusion criteria. Median reported ages and follow-up durations fell into the ranges 67-82 years and 12-84 months. Prescriptions fell into the range of 40-70 Gy in 3-10 fractions. Despite study heterogeneity, the pooled incidences of CWP and RF were estimated to be 8.94% and 5.27% respectively. Nineteen studies reported cwp grade: 58 of 308 patients (18.8%) experienced grades 3-4 CWP (no grade 5 events reported). Thirteen studies reported RF grade: grades 3-4 RF were observed in 9 of 113 patients (7.96%). A high chest wall V30 was an important predictor of CWP and RF. Conclusions: In patients with stage i nsclc, rates of CWP and RF after SBRT are low; however, tumour location, accurate toxicity reporting, and dose-fractionation schemes might alter those rates. Prospective correlation with dosimetry and quality of life assessment will further improve the understanding of CWP and RF after sbrt.