Jonathan W. Riess, MD, MS
Real-World Retrospective Study Suggests Inferior Outcomes to First-Line Systemic Treatment in Advanced NFE2L2 and KEAP1 Mutant Squamous NSCLC
Targeted therapies against oncogene-driven lung cancer, such as epidermal growth factor receptor (EGFR) and anaplastic lymphoma kinase (ALK), in lung adenocarcinoma have revolutionized lung cancer treatment. However, there are no US Food and Drug Administration–approved targeted therapies for commonly occurring mutations in advanced squamous non–small cell lung cancer (NSCLC).
NFE2L2 and KEAP1 mutations are molecular alterations that occur in about 25%-30% of squamous NSCLC. NFE2L2 encodes for the NRF2 transcription factor that is involved in the oxidative stress pathway and KEAP1 encodes for the KEAP1 protein, which is the negative regulator of NFE2L2. 1 When the NRF2-KEAP1 signaling pathway is disrupted, there is persistent activation of NRF2, which promotes cell proliferation and carcinogenesis and may contribute to resistance to cancer-directed treatments. Previous retrospective studies suggest that patients with lung cancers harboring NFE2L2 and KEAP1 mutations have a poorer prognosis and do worse with both systemic anticancer treatments and radiation. 2-5
Wu and colleagues , in a retrospective cohort study, identified 703 patients with squamous NSCLC from 2011 to 2018 who had NFE2L2 or KEAP1 mutations identified by comprehensive genomic profiling in the Flatiron Health-Foundation Medicine Clinico-Genomic Database. Real-world progression-free survival (PFS), defined as a distinct episode where the clinician concluded that there was growth or worsening of disease, was assessed by line and type of treatment, as was overall survival (OS). Patients with squamous NSCLC with NFE2L2/KEAP1 mutations had shorter real-world PFS to first-line treatment compared with patients whose tumors were wild-type for these mutations (4.54 months vs 6.25 months; P = .0027). Median OS was numerically shorter in patients with NFE2L2/KEAP1 mutations, but this was not statistically significant (13.59 vs 17.37 months; P = .41). This retrospective real-world analysis suggests that patients with squamous NSCLC and NFE2L2/KEAP1 mutations have inferior outcomes with systemic treatments and may have worsened OS; however, this was not statistically significant. Many of these patients were treated before the approval of the KEYNOTE-407 chemo-immunotherapy regimen in squamous NSCLC, so they did not have what we would consider contemporary standard treatment. Further studies are needed to evaluate the role of NRF2 activation in resistance to NSCLC treatments, and there is a need for therapeutics to target these common mutations in squamous NSCLC. Fortunately, there are current ongoing clinical trials. [6]
Segmentectomy Is Noninferior to and Improves Overall Survival Compared With Lobectomy in Selected Cases of Small Peripheral Early-Stage NSCLC
Lobectomy has been the standard of care for surgical treatment of early-stage NSCLC. Saji and colleagues investigated whether segmentectomy was noninferior to lobectomy in selected cases of small-sized peripheral NSCLC. This randomized, controlled, noninferiority trial was conducted at 70 institutions in Japan.
Patients with selected stage IA (American Joint Committee on Cancer [AJCC], seventh edition) NSCLC (peripheral tumors, £ 2 cm diameter, consolidation-to-tumor ratio > 0.5) were randomly assigned to undergo segmentectomy or lobectomy. The primary endpoint was OS. Pertinent secondary endpoints included postoperative respiratory function, relapse-free survival, and adverse events.
A total of 1106 patients were enrolled: 554 in the lobectomy group and 552 in the segmentectomy group. The 5-year OS was 94.3% for segmentectomy and 91.1% for lobectomy (hazard ratio 0.663; one-sided P < .001 for noninferiority; P = .0082 for superiority). In addition to the modestly improved OS observed, 5-year relapse-free survival was comparable between the groups (88% for segmentectomy and 87.9% for lobectomy). However, more local relapse was observed for segmentectomy (10.5%) than for lobectomy (5.4%) ( P = .0018). Despite significantly more locoregional recurrences with segmentectomy compared with lobectomy, rates of combined distant and locoregional relapses were similar. Slightly more patients died in the lobectomy group than the segmentectomy group, and the rate of cancer-related deaths, including second primary lung cancers, was higher in the lobectomy group. Interestingly, although segmentectomy had better OS, the survival advantage was not cancer-specific.
The mechanism by which segmentectomy improved survival over lobectomy in these selected patients with small, peripheral stage IA NSCLC is still unclear. Limitations of the study included that all patients were from one geographic region (Japan) and that the study was unblinded, which can introduce bias. We await the results of CALGB 140503: A Randomized Phase III Trial of Lobectomy versus Sublobar Resection for Small (< 2cm) Peripheral Non-Small Cell Lung Cancer (NCT00499330). This study is being done in a US population and includes nonanatomic wedge in its sublobar resection cohort.
The study by Saji and colleagues suggests that surgeons should consider segmentectomy in appropriate patients (select small stage IA NSCLC [peripheral tumors, £ 2 cm diameter, consolidation-to-tumor ratio > 0.5]), based on the modest improvement in OS compared with lobectomy.
Immunotherapy Activity in Cachexic and Noncachexic Patients With Advanced NSCLC and Clinical Outcomes, by Adipose Tissue Loss on Treatment
There are emerging data that body mass index (BMI) and the presence or absence of cachexia in cancers, including NSCLC, may change the efficacy of programmed cell death-ligand 1 (PD-L1) immune checkpoint inhibitors. Nishioka and colleagues , in a single-center retrospective cohort, examined patients with advanced NSCLC (40 with cachexia and 34 without cachexia) who received PD-L1 inhibitors (pembrolizumab, nivolumab, or atezolizumab). Patients were excluded if they had poor performance status, EGFR/ALK/ROS1 oncogene drivers, unknown PD-L1 expression status, and unknown weight loss in the 6 months before immunotherapy administration. In addition to BMI, measurements of adipose tissue quantity and muscle mass were used.
The overall response rate was 28.4% in the 74 patients analyzed. Patients with cachexia had a lower overall response rate than those without cachexia (15.0% vs 44.1%; P < .05). Among the patients without cachexia, those with total adipose tissue loss had a significantly longer PFS than those with total adipose tissue maintenance (18.5 months vs 2.86 months; P = .037), including in a multivariate analyses (hazard ratio 0.34; P < .05), after adjustment for PD-L1 expression and performance status (Eastern Cooperative Oncology Group [ECOG] 0 vs. 1).
Mechanistically, a paradoxical effect of obesity on T-cell function that relates to leptin, which is secreted by adipose tissue, has been observed in preclinical studies. 7 In a previously published study, obesity resulted in tumor progression and PD-1–mediated T-cell dysfunction, which can be overcome by PD-L1 blockade with improved clinical outcomes to these therapies in patients with obesity and cancer, including NSCLC. 7 This "obesity paradox" may underlie some of the findings observed in Nishioka and colleagues' study. More research needs to be done regarding the activity of immune checkpoint inhibition in NSCLC as it relates to BMI, cachexia, and amount of adipose tissue.
Additional References
1. Shibata T, Ohta T, Tong KI, et al. Cancer related mutations in NRF2 impair its recognition by Keap1-Cul3 E3 ligase and promote malignancy. Proc Natl Acad Sci U S A. 2008;105(36):13568-13573. doi: 10.1073/pnas.0806268105
2. Frank R, Scheffler M, Merkelbach-Bruse S, et al. Clinical and pathological characteristics of KEAP1- and NFE2L2-mutated non-small cell lung carcinoma (NSCLC). Clin Cancer Res. 2018;24:3087-3096. doi: 10.1158/1078-0432.CCR-17-3416
3. Binkley MS, Jeon YJ, Nesselbush M, et al. KEAP1/NFE2L2 mutations predict lung cancer radiation resistance that can be targeted by glutaminase inhibition. Cancer Discov. 2020;10(12):1826-1841. doi: 10.1158/2159-8290.CD-20-0282
4. Hellyer JA, Padda SK, Diehn M, et al. Clinical implications of KEAP1-NFE2L2 mutations in NSCLC. J Thorac Oncol. 2021;16(3):395-403. doi: 10.1016/j.jtho.2020.11.015
5. Jeong Y, Hellyer JA, Stehr H, et al. Role of KEAP1/NFE2L2 mutations in the chemotherapeutic response of patients with non-small cell lung cancer. Clin Cancer Res. 2020;26(1):274-281. doi: 10.1158/1078-0432.CCR-19-1237
6. Riess JW, Frankel P, Shackelford D, et al. Phase 1 trial of MLN0128 (sapanisertib) and CB-839 HCl (telaglenastat) in patients with advanced NSCLC (NCI 10327): Rationale and study design. Clin Lung Cancer. 2021;22:67-70. doi: 10.1016/j.cllc.2020.10.006