Erlotinib Versus Gemcitabine Plus Cisplatin as Neoadjuvant Treatment of Stage IIIA-N2 EGFR-Mutant Non–Small-Cell Lung Cancer (EMERGING-CTONG 1103): A Randomized Phase II Study

Somatic mutations in the tyrosine kinase (TK) domain of the epidermal growth factor receptor (EGFR) gene are reportedly associated with sensitivity of lung cancers to gefitinib (Iressa), kinase inhibitor. In-frame deletions occur in exon 19, whereas point mutations occur frequently in codon 858 (exon 21). We found from sequencing the EGFR TK domain that 7 of 10 gefitinib-sensitive tumors had similar types of alterations; no mutations were found in eight gefitinib-refractory tumors (P = 0.004). Five of seven tumors sensitive to erlotinib (Tarceva), a related kinase inhibitor for which the clinically relevant target is undocumented, had analogous somatic mutations, as opposed to none of 10 erlotinib-refractory tumors (P = 0.003). Because most mutation-positive tumors were adenocarcinomas from patients who smoked <100 cigarettes in a lifetime ("never smokers"), we screened EGFR exons 2-28 in 15 adenocarcinomas resected from untreated never smokers. Seven tumors had TK domain mutations, in contrast to 4 of 81 non-small cell lung cancers resected from untreated former or current smokers (P = 0.0001). Immunoblotting of lysates from cells transiently transfected with various EGFR constructs demonstrated that, compared to wild-type protein, an exon 19 deletion mutant induced diminished levels of phosphotyrosine, whereas the phosphorylation at tyrosine 1092 of an exon 21 point mutant was inhibited at 10-fold lower concentrations of drug. Collectively, these data show that adenocarcinomas from never smokers comprise a distinct subset of lung cancers, frequently containing mutations within the TK domain of EGFR that are associated with gefitinib and erlotinib sensitivity.

Results from phase II studies in patients with stage IIIA non-small-cell lung cancer with ipsilateral mediastinal nodal metastases (N2) have shown the feasibility of resection after concurrent chemotherapy and radiotherapy with promising rates of survival. We therefore did this phase III trial to compare concurrent chemotherapy and radiotherapy followed by resection with standard concurrent chemotherapy and definitive radiotherapy without resection. Patients with stage T1-3pN2M0 non-small-cell lung cancer were randomly assigned in a 1:1 ratio to concurrent induction chemotherapy (two cycles of cisplatin [50 mg/m(2) on days 1, 8, 29, and 36] and etoposide [50 mg/m(2) on days 1-5 and 29-33]) plus radiotherapy (45 Gy) in multiple academic and community hospitals. If no progression, patients in group 1 underwent resection and those in group 2 continued radiotherapy uninterrupted up to 61 Gy. Two additional cycles of cisplatin and etoposide were given in both groups. The primary endpoint was overall survival (OS). Analysis was by intention to treat. This study is registered with ClinicalTrials.gov, number NCT00002550. 202 patients (median age 59 years, range 31-77) were assigned to group 1 and 194 (61 years, 32-78) to group 2. Median OS was 23.6 months (IQR 9.0-not reached) in group 1 versus 22.2 months (9.4-52.7) in group 2 (hazard ratio [HR] 0.87 [0.70-1.10]; p=0.24). Number of patients alive at 5 years was 37 (point estimate 27%) in group 1 and 24 (point estimate 20%) in group 2 (odds ratio 0.63 [0.36-1.10]; p=0.10). With N0 status at thoracotomy, the median OS was 34.4 months (IQR 15.7-not reached; 19 [point estimate 41%] patients alive at 5 years). Progression-free survival (PFS) was better in group 1 than in group 2, median 12.8 months (5.3-42.2) vs 10.5 months (4.8-20.6), HR 0.77 [0.62-0.96]; p=0.017); the number of patients without disease progression at 5 years was 32 (point estimate 22%) versus 13 (point estimate 11%), respectively. Neutropenia and oesophagitis were the main grade 3 or 4 toxicities associated with chemotherapy plus radiotherapy in group 1 (77 [38%] and 20 [10%], respectively) and group 2 (80 [41%] and 44 [23%], respectively). In group 1, 16 (8%) deaths were treatment related versus four (2%) in group 2. In an exploratory analysis, OS was improved for patients who underwent lobectomy, but not pneumonectomy, versus chemotherapy plus radiotherapy. Chemotherapy plus radiotherapy with or without resection (preferably lobectomy) are options for patients with stage IIIA(N2) non-small-cell lung cancer. National Cancer Institute, Canadian Cancer Society, and National Cancer Institute of Canada.

Background Neoadjuvant anti-PD-1 may improve outcomes for patients with resectable NSCLC and provides a critical window for examining pathologic features associated with response. Resections showing major pathologic response to neoadjuvant therapy, defined as ≤10% residual viable tumor (RVT), may predict improved long-term patient outcome. However, %RVT calculations were developed in the context of chemotherapy (%cRVT). An immune-related %RVT (%irRVT) has yet to be developed. Patients and methods The first trial of neoadjuvant anti-PD-1 (nivolumab, NCT02259621) was just reported. We analyzed hematoxylin and eosin-stained slides from the post-treatment resection specimens of the 20 patients with non-small-cell lung carcinoma who underwent definitive surgery. Pretreatment tumor biopsies and preresection radiographic ‘tumor’ measurements were also assessed. Results We found that the regression bed (the area of immune-mediated tumor clearance) accounts for the previously noted discrepancy between CT imaging and pathologic assessment of residual tumor. The regression bed is characterized by (i) immune activation—dense tumor infiltrating lymphocytes with macrophages and tertiary lymphoid structures; (ii) massive tumor cell death—cholesterol clefts; and (iii) tissue repair—neovascularization and proliferative fibrosis (each feature enriched in major pathologic responders versus nonresponders, P  < 0.05). This distinct constellation of histologic findings was not identified in any pretreatment specimens. Histopathologic features of the regression bed were used to develop ‘Immune-Related Pathologic Response Criteria’ (irPRC), and these criteria were shown to be reproducible amongst pathologists. Specifically, %irRVT had improved interobserver consistency compared with %cRVT [median per-case %RVT variability 5% (0%–29%) versus 10% (0%–58%), P  = 0.007] and a twofold decrease in median standard deviation across pathologists within a sample (4.6 versus 2.2, P  = 0.002). Conclusions irPRC may be used to standardize pathologic assessment of immunotherapeutic efficacy. Long-term follow-up is needed to determine irPRC reliability as a surrogate for recurrence-free and overall survival.