SABR not inferior to VATS L-MLND in operable stage I non-small cell lung cancer
Stereotaxic ablative radiotherapy treatment yielded non-inferior long-term survival compared to video-assisted thoracoscopic surgical lobectomy with mediastinal lymph node dissection in operable stage IA non-small cell lung cancer.
Long-term survival after stereotaxic ablative radiotherapy (SABR) treatment appears to be non-inferior to video-assisted thoracoscopic surgical lobectomy with mediastinal lymph node dissection (VATS L-MLND) in patients with non-small lung cancer. operable stage IA cells (NSCLC), according to the results of the revised STARS assay (NCT02357992).
No significant difference between overall survival (OS) was noted between the 2 patient cohorts (RR: 0.86; 95% CI: 0.45-1.65; P = .65). Trial results indicated that median OS had not yet been reached in the SABR group (95% CI, not reached [NR]âNR), and the rate of OS at 3 and 5 years was 91% (95% CI, 85% to 98%) and 87% (95% CI, 79% to 95%), respectively. In the VATS L-MLND cohort, the 3-year OS rate was 91% (95% CI, 85% to 98%) and the 5-year rate was 84% ââ(95% CI, 76% to 93%). The study had a median follow-up of 5.1 years.
âThese results are important because the pooled analysis of the STARS and ROSEL trials had notable limitations; as a result, the SABR group of the STARS trial was reconstituted with a larger sample size, and long-term follow-up was performed and compared by protocol to that of a contemporary institutional cohort of VATS L-MLND cases. “, Investigators wrote. “This study, however, does not replace the Phase 3 trials (for example, VALOR [NCT02984761], which could take at least 5 more years for registration, plus additional time for follow-up).
The single-arm, prospective STARS trial enrolled new patients who had similar primary and secondary goals, eligibility, and SABR dosage. The study recruited patients 18 years of age or older with newly diagnosed and histologically confirmed NSCLC. A Zubrod Performance Index of 0 to 2 was required, as well as a tumor diameter of 3 cm or less. Those with carcinoid histology, synchronous primary lung cancer, and prior pulmonary or mediastinal radiotherapy were not eligible to enroll.
Radiation was administered at a dose of 54 Gy in 3 fractions or 50 Gy in 4 fractions with a simultaneous integrated increase in gross internal tumor volume of 60 Gy. SABR was administered on consecutive days. Those who received VATS L-MLND did so by thoracic surgeons who specialize in chest cancer surgery.
The primary endpoint of the study was OS at 3 years, with secondary endpoints including progression-free survival (PFS) and cancer-specific survival (CSS).
Eighty patients were included from September 1, 2015 to January 31, 2017, the final follow-up date being September 30, 2020. Most of the patients included had adenocarcinomas and 67% had peripheral tumors. The average tumor size was 1.83 cm.
Additional results from the SABR cohort indicated that 10 patients had died at the time of the data lock on September 30, 2020, of which 6 were specific for cancer. In addition, 15 patients developed disease progression. The median PFS was not reached (95% CI, NR-NR, and the 3 and 5 year PFS rates were 80% (95% CI, 72% to 89%) and 77% (CI 95%, 68% -87%) 71% – 90%; P = 0.57). In addition, the median CSS had not been reached and the rates of CSS at 3 and 5 years were 95% (95% CI, 90% -100%) and 92% (95% CI, 86% -98% ).
In terms of safety, investigators reported that SABR was well tolerated and produced no grade 4/5 toxicity. Adverse reactions (AEs) included grade 3 dyspnea (1%), grade 2 lung disease (1%), and grade 2 pulmonary fibrosis (1%). In particular, no serious AEs, treatment changes, or treatment interruptions occurred after treatment with SABR.
The most common AEs in the VATSL-MLND cohort were pulmonary (38%) and cardiovascular (13%). Other complications included renal failure (1%), gastrointestinal complications (4%), genitourinary complications (4%), postoperative transfusions (5%), bleeding requiring readmission (1%) and wound complications (5%).
Reference
Chang JY, Mehran RJ, Feng L, et al. Stereotaxic ablative radiation therapy for operable stage I non-small cell lung cancer (revised STARS): long-term results from a prospective single-arm trial with predefined comparison to surgery. Lancet Oncol. 2021; 22: 1448-1457. doi: 10.1016 / S1470-2045 (21) 00401-0