According to a prospective multicenter trial, one fifth of patients with operable early-stage non-small cell lung cancer (NSCLC) had major pathologic responses (MPR) and over 40% had pathologic downstaging after neoadjuvant atezolizumab.
Out of 144 patients, 30 achieved MPR (defined as ≤10% viable tumour cells), 10 of whom had pathologic complete response (pCR), while 66 experienced downstaging and upstaging occurred in 29.
Jay M Lee, MD, of the David Geffen School of Medicine at the University of California Los Angeles, explained: “The LCMC (Lung Cancer Mutation Consortium)3 study successfully met its primary endpoint of achieving major pathologic response in 21% of patients, and a pathologic complete response rate of 7%. Neoadjuvant atezolizumab monotherapy was well tolerated, with no new safety signals, and resection was performed with low perioperative morbidity and mortality, usually within a narrow protocol window, with a short time frame from completion of atezolizumab and with a corresponding high R0, or complete resection rate.”
Some 90% of patients were still alive at 18 months, and 80% were disease-free and alive. The findings indicate that neoadjuvant therapy with an immune checkpoint inhibitor (ICI) is possible thought it does make surgery harder, said invited discussant Shinichi Toyooka, MD, of Okayama University Hospital. Similar outcomes were seen in patients with stage I-II versus stage III disease, although survival data is currently lacking, requiring follow-up to find out if single-agent ICI is sufficient for all patients with operable NSCLC.
“I think single ICI can be used for early-stage disease and poor performance status,” said Toyooka. “On the other hand, a combination of ICI and chemotherapy is suitable for advanced-but-resectable cases.”
Minimally invasive surgery (robotic or VATS) was successful in 86 patients, and 15 others required conversion to thoracotomy. Lee said 79% of patients underwent lobectomy, and 3% had segmentectomy or wedge procedures. R0 (clear surgical margins) status was achieved in 92% of the 159 patients who went to surgery.
The trial included 181 patients with newly diagnosed, resectable stage Ib-IIIa and selected IIIb (T4 because of mediastinal invasion) NSCLC and no targetable mutations, of which 159 underwent surgery. 15 patients were later found to have EGFR/ALK-positive disease and excluded from analysis. Patients had radiographic staging before and after two cycles of atezolizumab and then underwent surgery within 30 to 50 days after finishing neoadjuvant therapy.
Minimally invasive surgery (robotic or VATS) was successful in 86 patients, and 15 others required conversion to thoracotomy; 79% of patients underwent lobectomy, and 3% had segmentectomy or wedge procedures. R0 (clear surgical margins) status was achieved in 92% of the 159 patients who went to surgery.
Source:MedPage Today
Presentation reference: Lee JM, et al “Surgical and clinical outcomes with neoadjuvant atezolizumab in resectable stage Ib-IIIb NSCLC: LCMC3 trial primary analysis” WCLC 2020; Abstract PS01-05.
