New horizons for uncommon mutations in non-small cell lung cancer: BRAF, KRAS, RET, MET, NTRK, HER2

The 2004 discovery of EGFR mutations,followed by ALK rearrangements,ushered in a targeted therapy era for advanced non-small cell lung cancer(NSCLC).Tyrosine kinase inhibitors targeting gene alterations have substantially improved survival and quality of life for patients with NSCLC.In the last decade,rearrangements of the ROS1 oncogene have been incorporated into healthcare practice that are applicable to another small subgroup of patients who benefit from similar targeted strategies.Recent genome studies of lung adenocarcinoma have identified other possible therapeutic targets,including RET,NTRK fusions,c-MET alterations,and activating mutations in KRAS,BRAF,and HER2,all with frequencies greater than 1%.Lung cancers harbouring these genome changes can potentially be treated with agents approved for other indications or under clinical development.This review updates the therapeutic arsenal that especially targets those genes.

Clinical characteristics and response to tyrosine kinase inhibitors of patients with non-small cell lung cancer harboring uncommon epidermal growth factor receptor mutations

Objective： To investigate the clinical features of patients with non-small cell lung cancer（NSCLC） harboring uncommon epidermal growth factor receptor（EGFR） mutations, and the treatment outcomes of EGFR tyrosine kinase inhibitors（TKIs） in these patients.Methods： We retrospectively analyzed the data of 128 NSCLC patients pathologically diagnosed with uncommon EGFR mutation in the Department of Pathology, National Cancer Center/Cancer Hospital, Chinese Academy of Medical Sciences ＆ Peking Union Medical College and Beijing Hospital from January 2010 to December 2015, including 40 advanced patients who received EGFR-TKI.Results： Among the total 128 patients, 11 patients were non-adenocarcinoma, including squamous carcinoma（3.9%）, adenosquamous carcinoma（2.3%）, large cell carcinoma（0.8%）, and composite neuroendocrine carcinoma（1.6%）. Single mutations accounted for 75.0%（96/128）, including G719X（29.7%）, S768I（18.0%）, 20 exon insertion（13.3%）, L861Q（12.5%）, De novo T790M（0.8%）, and T725（0.8%）. Thirty-two patients harbored complex mutations. Forty advanced patients received EGFR-TKI, the objective response rate（ORR） was 20.0%,the disease control rate（DCR） was 85.0%, and the progression-free survival（PFS） was 6.4 [95% confidence interval（95% CI）, 4.8–7.9] months. The exploratory analysis of tumor response and PFS in 33 patients with G719X/S768I/L861 Q subtypes showed that ORR was 21.2%（7/33）, the DCR was 93.9%（31/33）, and PFS was 7.6（95% CI, 5.8–9.4） months. Patients with exon 20 insertion mutation and De novo T790 M experienced rapid disease progression with PFS no more than 2.7 months.Conclusions： Uncommon EGFR-mutant NSCLCs are heterogeneous, EGFR-TKIs can have different efficacy in this specific subtype, and thus further individual assessment is required for each case.

Uncommon EGFR mutations in a cohort of Chinese NSCLC patients and outcomes of first-line EGFR-TKIs and platinum-based chemotherapy

Objective： Data on the clinical activity of epidermal growth factor receptor （EGFR） tyrosine kinase inhibitors （TKIs） in patients with non-small-cell lung cancer （NSCLC） and uncommon EGFR mutations remain insufficient. This study aimed to investigate the effect of first-line EGFR-TKIs or platinum-based chemotherapy in NSCLC patients with uncommon EGFR mutations. Methods： We retrospectively enrolled 504 patients with EGFR-mutant NSCLC. The clinical characteristics and treatment outcomes were collected and compared between patients with common and uncommon EGFR-mutant NSCLC. Results： Seventy patients （13.9%） harboring uncommon EGFR mutations were included. Thirty of these patients received EGFR-TKIs and 40 received platinum-based chemotherapy as first-line therapy. The objective response rate （ORR） and median progression-free survival （mPFS） of patients treated with TKIs in the uncommon mutation group was significantly inferior to that in the common mutation group （ORR： 23.3% vs. 51.8%, P=0.003; mPFS： 7.1 vs. 10.9 months, P〈0.001）. In the uncommon group, mPFS was similar between first-line EGFR-TKIs treatment and platinum-based chemotherapy （7.1 vs. 6.1 months, P=0.893）. In patients with EGFR G719X or L861Q mutations, the mPFS was longer in the first-line EGFR-TKIs treatment group than in the chemotherapy group, but the difference was not statistically significant （G719X： 8.2 vs. 5.8 months, P=0.061; L861Q： 7.6 vs. 4.1 months, P=0.872）. Multivariate analyses identified adenocarcinoma （P=0.003） as the independent predictive factor for PFS in patients with uncommon EGFR mutations who were treated with first-line EGFR-TKIs. Conclusions： The current study demonstrated that the effect of first-line EGFR-TKIs was similar to that of platinum-based chemotherapy in patients with uncommon EGFR-mutant NSCLC. Adenocarcinoma was the independent predictive factor for PFS in uncommon EGFR-mutant NSCLC patients treated with first-line EGFR- TKIs.

Brain metastasis in non-small cell lung cancer (NSCLC) patients with uncommon EGFR mutations： a report of seven cases and literature review

Brain metastasis(BM)arising from non-small cell lung cancer(NSCLC)with rare epidermal growth factor receptor(EGFR)mutations is quite rare.The prognosis and therapeutic effects of BM remain enigmatic.To the best of our knowledge,this is the first report to make a separate analysis of BM from NSCLC patients with original uncommon EGFR mutations.We retrospectively reviewed 7 cases of BM arising from 42 cases of uncommon EGFR mutated lung cancer in Tianjin Medical University Cancer Institute and Hospital.We also performed a literature review to assess therapeutic features and outcomes.

Response to dacomitinib in advanced non-small-cell lung cancer harboring the rare delE709_T710insD mutation:A case report

BACKGROUND Tyrosine kinase inhibitors(TKI)have been the standard first-line therapy for advanced non-small cell lung cancer(NSCLC)of epidermal growth factor receptor(EGFR)sensitive mutations.Uncommon EGFR mutations are increasingly reported with the development of next-generation sequencing.However,their sensitivity to TKIs is variable with limited clinical evidence.CASE SUMMARY Here,we report a patient with the rare delE709_T710insD mutation,who showed the favorable efficacy of dacomitinib and achieved a partial response with a progression-free survival of 7.0 mo.CONCLUSION To our knowledge,this is the first report displaying the clinical efficacy of dacomitinib for patients with delE709_T710insD,which may help to provide alternatives in non-classical variant NSCLC patients.Further studies are warranted to make the optimal choice of EGFR-TKI for rare mutations.

Antitumor activity of aumolertinib, a third-generation EGFR tyrosine kinase inhibitor, in non-small-cell lung cancer harboring uncommon EGFR mutations

Uncommon epidermal growth factor receptor(EGFR) mutations account for 10% 20% of all EGFR mutations in non-small-cell lung cancer(NSCLC). The uncommon EGFR-mutated NSCLC is associated with poor clinical outcomes and generally achieved unsatisfactory effects to the current therapies using standard EGFR-tyrosine kinase inhibitors(TKIs), including afatinib and osimertinib. Therefore, it is necessary to develop more novel EGFR-TKIs to treat uncommon EGFR-mutated NSCLC.Aumolertinib is a third-generation EGFR-TKI approved in China for treating advanced NSCLC with common EGFR mutations. However, it remains unclear whether aumolertinib is effective in uncommon EGFR-mutated NSCLC. In this work, the in vitro anticancer activity of aumolertinib was investigated in engineered Ba/F3 cells and patient-derived cells bearing diverse uncommon EGFR mutations. Aumolertinib was shown to be more potent in inhibiting the viability of various uncommon EGFR-mutated cell lines than those with wild-type EGFR. And in vivo, aumolertinib could also significantly inhibit tumor growth in two mouse allograft models(V769-D770insASV and L861Q mutations) and a patientderived xenografts model(H773-V774insNPH mutation). Importantly, aumolertinib exerts responses against tumors in advanced NSCLC patients with uncommon EGFR mutations. These results suggest that aumolertinib has the potential as a promising therapeutic candidate for the treatment of uncommon EGFR-mutated NSCLC.