Top Line: Is SBRT superior to hypofractionated chemoradiation for stage I NSCLC?
The study: SBRT (or SABR) provides high rates of local control in patients with early stage NSCLC. In the CHISEL trial, SBRT resulted in superior local control compared with conventionally fractionated RT (89% v 65%). The LUSTRE trial pitted SBRT against a slightly more formidable opponent of hypofractionated RT. It included 233 patients with inoperable, peripheral (72.5%) or central (27.5%), stage I NSCLC. They were randomized to receive SBRT (48 Gy in 4 for peripheral and 60 Gy in 8 for central) or hypofractionated chemoradiation (60 Gy in 15). The study was designed to detect an improvement of 75→ 87.5% at 3 years. Although numerically lower, hypofractionated RT performed better than expected, and the difference in local control at 3 years wasn’t statistically significant (87.6% SBRT v 81.2% HF; HR=0.61, P=.15). OS and EFS were also similar at 3 years. While LUSTRE doesn’t really question the superior local control of SBRT, it does provide useful comparisons of control and toxicity with the 60 Gy in 15 fractions regimen, which is sometimes employed for more advanced cases or ultracentral cases. Toxicity was low in both groups with 5.2% of SBRT and 3% of HF patients experiencing grade 3-4 toxicity. There was one grade 5 hemoptysis event in a patient with an ultracentral tumor treated with 60 Gy in 8 fractions. A total of 23 patients in the SBRT arm had ultracentral tumors, and 17% developed grade 3+ toxicity.
TBL: In the LUSTRE trial, local control at 3 years for stage I NSCLC was 87.6% with SBRT and 81.2% with hypofractionated RT, and toxicity was similar between groups. | Swaminath, JAMA Oncol 2024
The study: SBRT (or SABR) provides high rates of local control in patients with early stage NSCLC. In the CHISEL trial, SBRT resulted in superior local control compared with conventionally fractionated RT (89% v 65%). The LUSTRE trial pitted SBRT against a slightly more formidable opponent of hypofractionated RT. It included 233 patients with inoperable, peripheral (72.5%) or central (27.5%), stage I NSCLC. They were randomized to receive SBRT (48 Gy in 4 for peripheral and 60 Gy in 8 for central) or hypofractionated chemoradiation (60 Gy in 15). The study was designed to detect an improvement of 75→ 87.5% at 3 years. Although numerically lower, hypofractionated RT performed better than expected, and the difference in local control at 3 years wasn’t statistically significant (87.6% SBRT v 81.2% HF; HR=0.61, P=.15). OS and EFS were also similar at 3 years. While LUSTRE doesn’t really question the superior local control of SBRT, it does provide useful comparisons of control and toxicity with the 60 Gy in 15 fractions regimen, which is sometimes employed for more advanced cases or ultracentral cases. Toxicity was low in both groups with 5.2% of SBRT and 3% of HF patients experiencing grade 3-4 toxicity. There was one grade 5 hemoptysis event in a patient with an ultracentral tumor treated with 60 Gy in 8 fractions. A total of 23 patients in the SBRT arm had ultracentral tumors, and 17% developed grade 3+ toxicity.
TBL: In the LUSTRE trial, local control at 3 years for stage I NSCLC was 87.6% with SBRT and 81.2% with hypofractionated RT, and toxicity was similar between groups. | Swaminath, JAMA Oncol 2024