Stereotactic body radiation therapy for ultra-central lung malignancies: an updated systematic review and meta-analysis

PURPOSE: Stereotactic body radiotherapy (SBRT) is a highly effective and well-tolerated treatment modality for peripherally located early-stage non-small cell lung cancer as well as pulmonary metastases. However, its feasibility and safety remain uncertain in patients with ultra-central (UC) lung tumors. This study aims to evaluate the efficacy and safety of SBRT in the management of UC lung malignancies. METHODS: A systematic review of the available literature was conducted in accordance with the PRISMA guidelines, incorporating studies that reported both treatment-related side effects and therapeutic efficacy associated with SBRT for UC lung malignancies. Patient characteristics, prescription doses, local control (LC), overall survival (OS), and side effects information were extracted. Clinical outcomes were analyzed using the random-effects model. Meta-regression was conducted to determine the effect of various covariates on LC and OS outcomes. RESULTS: and 1- and 2-year OS rates (P = 0.025, P = 0.002, respectively), and a significantly negative association between PTV volume and 1- and 2-year OS (P = 0.031, P < 0.001, respectively). The pooled rates of grade ≥ 3 and grade 5 treatment-related side effects were 9% (95% CI: 6-14%) and 2% (95% CI: 1-5%), respectively. CONCLUSION: This meta-analysis demonstrates that SBRT achieves favorable LC rates and is a relatively safe treatment for UC lung malignancies. Although the pooled rate of grade 5 side effects, at 2%, was within an acceptable range, vigilance remains essential. Further prospective research is warranted to verify our conclusions.