Clinicopathologic Characteristics,Treatment Outcomes,and Acquired Resistance Patterns of Atypical EGFR Mutations and HER2 Alterations in Stage IV Non–Small-Cell Lung Cancer

BackgroundThe clinicopathologic characteristics, acquired resistance patterns, and outcomes among patients with atypical EGFR mutations and HER2 alterations remain underexplored.Patients and MethodsA single-center retrospective review was conducted. Oncogenes assessed include typical EGFR (t-EGFR; exon 19 del and L858R), atypical EGFR (a-EGFR; G719X, exon 20, L861Q), HER2 (exon 19, exon 20, amplifications), gene fusions (ALK, ROS1, RET), RAS (KRAS, NRAS), and RAF (BRAF V600E). Progression-free survival (PFS), overall survival (OS), disease control rate, and objective response rate (Response Evaluation Criteria in Solid Tumors 1.1) were collected.ResultsAmong 570 patients, we found 55 a-EGFR mutations (13 G719X, 38 exon 20, 4 L861Q) and 31 HER2 alterations (2 exon 19 mutations, 27 exon 20 insertions, 2 amplifications). Patients with EGFR and HER2 alterations had increased lung and bone metastases relative to patients with gene fusions, RAS/RAF mutations, and no identified driver oncogenes (P < .001). Patients with EGFR exon 20 insertions had a median PFS to EGFR tyrosine kinase inhibitors (TKIs) of 5 months and an OS of 16 months—significantly worse than exon 19 del and L858R (Bonferroni correction; P < .001), but not G719X or L861Q. Relative to t-EGFR mutations, T790M and MET amplification occurred less frequently as acquired resistance mechanisms among a-EGFR samples (P < .001). Ten patients with a-EGFR mutations and HER2 alterations received single-agent immune checkpoint inhibitors (ICIs) with no radiographic responses and a median PFS of 2 months.ConclusionEGFR and HER2-mutated NSCLC have a high rate of synchronous lung and bone metastases. Patients with a-EGFR mutations have inferior responses to EGFR-directed therapies with lower rates of acquired T790M and MET amplification. Responses to ICIs are uniformly poor. Novel therapeutic approaches are needed.     

KRAS mutations are associated with inferior clinical outcome in patients with metastatic colorectal cancer,but are not predictive for benefit with cediranib

PurposeThe prognostic potential of KRAS mutations in advanced colorectal cancer (CRC) patients and the impact of KRAS mutation status on the effectiveness of chemotherapy or vascular endothelial growth factor (VEGF) signalling inhibitor therapy remain unclear. KRAS mutation status was evaluated retrospectively as a potential prognostic/predictive marker of clinical outcomes using tumour samples from patients with metastatic CRC receiving cediranib or placebo plus FOLFOX/XELOX in a Phase III trial (HORIZON II; NCT00399035).MethodsKRAS codon 12 and 13 mutation analyses were performed using a commercially available, allele-specific, amplification refractory mutation system (ARMS)-based polymerase chain reaction (PCR) assay. Retrospective analyses of progression-free survival (PFS) and overall survival (OS) according to KRAS mutation status were performed for patients randomised to cediranib 20 mg or placebo.ResultsKRAS status was determined in 599/1076 patients (cediranib 20 mg, n = 285/502; cediranib 30 mg, n = 110/216; placebo, n = 204/358). Baseline characteristics were similar across KRAS mutant (n = 258; 24.0%), wild-type (n = 341; 31.7%) and status unknown (n = 477; 44.3%) groups. There was a trend towards improved PFS and OS in the wild-type versus mutant subgroups independent of treatment (cediranib 20 mg and placebo: PFS hazard ratio (HR) = 0.85 [median PFS: wild-type = 8.5 months; mutant = 8.3 months]; OS HR = 0.71 [median OS: wild-type = 20.9 months; mutant = 16.9 months]). Treatment effects were similar between KRAS subgroups for cediranib 20 mg versus placebo (PFS: wild-type HR = 0.78, mutant HR = 0.82; OS: wild-type HR = 0.92, mutant HR = 1.01).ConclusionData from this large randomised Phase III study show that KRAS codon 12/13 mutations have negative prognostic value in metastatic CRC patients receiving treatment with FOLFOX/XELOX, but KRAS mutation status is not predictive of treatment benefit with cediranib, using PFS or OS.     

Correlation of FCGR3A and EGFR germline polymorphisms with the efficacy of cetuximab in KRAS wild-type metastatic colorectal cancer

BackgroundNext to KRAS mutation status, additional predictive markers are needed for the response to cetuximab in patients with metastatic colorectal cancer (mCRC). Previous studies indicated that germline polymorphisms in specific genes may predict efficacy and toxicity of cetuximab in mCRC patients.MethodsGermline DNA was isolated from 246 KRAS wild-type mCRC patients who were treated in the phase III CAIRO2 study with chemotherapy and bevacizumab alone or with the addition of cetuximab. Associations of epidermal growth factor (EGF) 61A > G, EGF receptor (EGFR) CA_14–22, cyclin D1 (CCND1) 932G > A, fragment-C gamma receptor (FCGR) 2A 535A > G and FCGR3A 818A > C polymorphisms with progression-free survival (PFS) and cetuximab-related skin toxicity were studied.ResultsIn cetuximab-treated patients, the FCGR3A 818C-allele was associated with decreased PFS compared with the FCGR3A 818AA genotype (median PFS, 8.2 [95%CI, 6.7–10.3] versus 12.8 [95%CI, 10.3–14.7] months, respectively; HR, 1.57 [95%CI, 1.06–2.34]; P = .025). The EGFR ? 20 genotype was associated with decreased PFS compared with the EGFR < 20 genotype (median PFS, 7.6 [95%CI, 6.7–10.0] versus 12.4 [95%CI, 10.3–13.4] months, respectively; HR, 1.58 [95%CI, 1.06–2.35]; P = .024). The FCGR3A and EGFR polymorphisms were not associated with PFS in patients treated without cetuximab. None of the polymorphisms were associated with the incidence of grades 2–3 skin toxicity.ConclusionEGFR and FCGR3A germline polymorphisms are associated with PFS in KRAS wild-type mCRC patients treated with cetuximab, bevacizumab and chemotherapy.     

RAC1b overexpression correlates with poor prognosis in KRAS/BRAF WT metastatic colorectal cancer patients treated with first-line FOLFOX/XELOX chemotherapy

IntroductionChemotherapy is the principal treatment in metastatic colorectal cancer (mCRC) patients. RAC1b, a RAC1 spliced variant, is over-expressed in colorectal cancer (CRC), and impairs apoptosis by activation of nuclear-factor-KB. Since RAC1b has been associated with the BRAF^V600E mutation, associated with poor prognosis in CRC, we evaluated the role of RAC1b expression as a predictor of chemotherapy efficacy in mCRC.MethodsWe analysed KRAS and BRAF mutation, microsatellite instability and RAC1b expression in 157 mCRC patients treated with FOLFOX/XELOX in first-line therapy.ResultsKRAS mutations were detected in 46 patients (34%), 10 patients were BRAF mutant (7%) and 79 were WT for both, KRAS and BRAF (59%). RAC1b overexpression was found in 30 patients (19%). In the multivariate analysis, BRAF mutational status was a poor prognostic factor for overall survival (OS); hazard ratio (HR), 2.78 (95% confidence interval (CI), 1.35–5.72; p = 0.0057). RAC1b overexpression was a poor survival factor for OS (HR, 2.35; 95% CI, 1.2–4.59; p = 0.01) and progression-free survival (PFS) (HR, 2.4; 95% CI, 1.2–4.78; p = 0.01) in KRAS/BRAF WT mCRC patients.ConclusionsRAC1b overexpression constitutes a marker of poor prognosis in KRAS/BRAF WT mCRC patients treated with first-line FOLFOX/XELOX therapy.     

Insulin-like growth factor type 1 receptor (IGF-1R) exclusive nuclear staining: A predictive biomarker for IGF-1R monoclonal antibody (Ab) therapy in sarcomas

AimsA minority of patients with advanced sarcoma achieve prolonged progression free survival (PFS) with insulin growth factor type 1 receptor (IGF-1R) monoclonal antibody (Ab) therapy. A biomarker identifying those patients beforehand would be useful to select patients for the development of these agents.MethodsThis single centre series includes patients with unresectable or metastatic soft tissue sarcomas (STS), Ewing sarcoma (ES) and osteosarcoma treated with IGF-1R Ab (R1507, IMC-A12, SCH 717454 and CP-751.871) in the Centre Léon Bérard. Tumour samples were analysed by immunohistochemistry for expression of IGF-1R, insulin-like growth factor binding protein type 3 (IGFBP-3), Ki67, epidermal growth factor receptor (HER1) and human epidermal growth factor receptor 2 (HER2). Predictive factors for PFS and overall survival (OS) were investigated.ResultsAll tumour samples had a positive IGF-1R immunostaining on 60% to 100% of tumour cells. IGFBP-3 immunostaining was observed in 12 (75%) samples with 5% to 100% of positive cells. IGF-1R immunostaining was nuclear (n = 9, 56%), cytoplasmic (n = 4, 25%), or nuclear + cytoplasmic (n = 3, 19%). Neither IGFBP-3 expression, nor Ki67 was correlated to PFS. HER2 and HER1 staining were positive in 0 and 2 samples respectively (both primary resistant to IGF-1R Ab therapy). Exclusive intra-nuclear immunoreactivity for IGF-1R was significantly associated with a better PFS (p = 0.01) and OS (p = 0.007).ConclusionExclusive nuclear localisation of IGF-1R is an easily testable biomarker associated with a better PFS and OS for patients treated with IGF-1R Ab therapy. Nuclear localisation of IGF-1R in tumour cells might be a hallmark of pathway activation.     

A phase III,randomized, open-label study of ASP8273 versus erlotinib or gefitinib in patients with advanced stage IIIB/IV non-small-cell lung cancer

BackgroundASP8273, a novel, small molecule, irreversible tyrosine kinase inhibitor (TKI) specifically inhibits the epidermal growth factor receptor (EGFR) in patients with activating mutations or EGFR T790M resistance mutations. The current study examines the efficacy, safety, and tolerability of ASP8273 versus erlotinib or gefitinib in patients with non-small-cell lung cancer (NSCLC) with activating EGFR mutations not previously treated with an EGFR inhibitor.Patients and methodsThis global, phase III, open-label, randomized study evaluated ASP8273 versus erlotinib/gefitinib in patients with locally advanced, metastatic, or unresectable stage IIIB/IV NSCLC with activating EGFR mutations. They were ineligible if they received prior chemotherapy for metastatic disease. The primary end point was progression-free survival (PFS), and secondary end points included overall survival, investigator-assessed PFS, best overall response rate (ORR), disease control rate, duration of response (DoR), and the safety/tolerability profile.ResultsPatients (n = 530) were randomized 1 : 1 to receive ASP8273 (n = 267) or erlotinib/gefitinib (n = 263). Patient demographics between both treatment groups were generally balanced. Median PFS was 9.3 months (95% CI 5.6–11.1 months) for patients receiving ASP8273 and 9.6 months (95% CI 8.8–NE) for the erlotinib/gefitinib group, with a hazard ratio of 1.611 (P = 0.992). The ORR in the ASP8273 group was 33% (95% CI 27.4–39.0) versus 47.9% (95% CI 41.7–54.1) in the erlotinib/gefitinib group. Median DoR was similar for both groups (9.2 months for ASP8273 versus 9.0 months for erlotinib/gefitinib). More grade ≥3 treatment-emergent adverse events (TEAEs) occurred in patients receiving ASP8273 than in those receiving erlotinib/gefitinib (54.7% versus 43.5%). An independent data monitoring committee carried out an interim safety analysis and recommended discontinuing the study due to toxicity and limited predicted efficacy of ASP8273 relative to erlotinib/gefitinib.ConclusionsFirst-line ASP8273 did not show improved PFS or equivalent toxicities versus erlotinib/gefitinib.ClinicalTrial.gov numberNCT02588261.     

Location of colon cancer (right-sided versus left-sided) as a prognostic factor and a predictor of benefit from cetuximab in NCIC CO.17

BackgroundRight- and left-sided colon cancers (RC, LC) differ with respect to biology, pathology and epidemiology. Previous data suggest a mortality difference between RC and LC. We examined if primary tumour side also predicts for outcome in chemotherapy refractory, metastatic colon cancer (MCC). We also compared RC versus LC as a predictor of efficacy of epidermal growth factor receptor (EGFR) inhibition with cetuximab.MethodsReanalyzing NCIC CO.17 trial (cetuximab versus best supportive care [BSC]), we coded the primary tumour side as RC (caecum to transverse colon) or LC (splenic flexure to rectosigmoid). The association between tumour side and baseline characteristics was assessed. Cox regression models determined factors affecting overall survival (OS) and progression free survival (PFS).ResultsPatients with RC (150/399) had more poorly differentiated, mutant KRAS, mutated PIK3CA and wild-type BRAF tumours, fewer liver and lung metastases, and shorter interval between diagnosis and study entry. Among BSC patients, tumour side was not prognostic for PFS (hazard ratios (HR) 1.07 [0.79–1.44], p = 0.67) or OS (HR 0.96 [0.70–1.31], p = 0.78). Among wild-type KRAS patients, those with LC had significantly improved PFS when treated with cetuximab compared to BSC (median 5.4 versus 1.8 months, HR 0.28 [0.18–0.45], p < 0.0001), whereas those with RC did not (median 1.9 versus 1.9 months, HR 0.73 [0.42–1.27], p = 0.26), [interaction p = 0.002].ConclusionIn refractory MCC, tumour location within the colon is not prognostic, but is strongly predictive of PFS benefit from cetuximab therapy. Additional research is needed to understand the molecular differences between RC and LC and their interaction with EGFR inhibition.     

Efficacy and Safety of Anti–PD-1 Immunotherapy in Patients With Advanced NSCLC With BRAF,HER2, or MET Mutations or RET Translocation: GFPC 01-2018

IntroductionImmune-checkpoint inhibitor (ICI) efficacy in patients with NSCLC harboring molecular alterations remains poorly elucidated. This study was undertaken to determine ICI efficacy against BRAF-, HER2-, MET-, and RET-NSCLC in a real-world setting.MethodsIn this retrospective, multicenter study in ICI-treated BRAF-, HER2-, MET- or RET-NSCLCs, we analyzed clinical characteristics and outcomes: ICI-treatment duration, progression-free survival (PFS), objective response rate, duration of response, and overall survival (OS).ResultsThere were 107 patients with NSCLC (mean age, 65.5 y) included from 21 centers: 37% were never-smokers, 54% were men, and 93% had adenocarcinoma. Among them, 44 had BRAF mutation (V600: 26), 23 had HER2 mutation, 30 had MET mutation, and nine had RET translocation. Programmed cell death ligand 1 (PD-L1) status was known for 70 patients and was greater than or equal to 1% in 34 patients. Before ICI, patients had received a median of one treatment line. Median duration of response, PFS, and OS were 15.4 (95% confidence interval [CI]: 12.6–not reached [NR]) months, 4.7 (95% CI: 2.3–7.4) months, and 16.2 (95% CI: 12.0–24.0) months, respectively, for the entire cohort. The response rates for BRAF-V600, BRAF–non-V600, HER2, MET, and RET-altered NSCLC were 26%, 35%, 27%, 36%, and 38%, respectively. For patients who were PD-L1 negative and those who were PD-L1 positive, PFS was 3.0 (95% CI: 1.2–NR) and 4.3 (95% CI: 2.1–8.5) months, respectively, and OS was 11.7 (95% CI: 4.1–NR) and 35.8 (95% CI: 9.0–35.2) months, respectively. Toxicities were reported in 28 patients (26%), including 11 patients (10%) with a grade greater than or equal to three.ConclusionsIn this real-world setting, ICI efficacy against patients with BRAF-, HER2-, MET-, or RET-NSCLC seemed close to that observed in unselected patients with NSCLC. Large prospective studies on these subsets of patients are needed.     

Unique genetic profiles from cerebrospinal fluid cell-free DNA in leptomeningeal metastases of EGFR-mutant non-small-cell lung cancer: a new medium of liquid biopsy

BackgroundLeptomeningeal metastases (LM) are more frequent in non-small-cell lung cancer (NSCLC) with epidermal growth factor receptor (EGFR) mutations. Due to limited access to leptomeningeal lesions, the purpose of this study was to explore the potential role of cerebrospinal fluid (CSF) as a source of liquid biopsy in patients with LM.Patients and methodsPrimary tumor, CSF, and plasma in NSCLC with LM were tested by next-generation sequencing. In total, 45 patients with suspected LM underwent lumbar puncture, and those with EGFR mutations diagnosed with LM were enrolled.ResultsA total of 28 patients were enrolled in this cohort; CSF and plasma were available in 26 patients, respectively. Driver genes were detected in 100% (26/26), 84.6% (22/26), and 73.1% (19/26) of samples comprising CSF cell-free DNA (cfDNA), CSF precipitates, and plasma, respectively; 92.3% (24/26) of patients had much higher allele fractions in CSF cfDNA than the other two media. Unique genetic profiles were captured in CSF cfDNA compared with those in plasma and primary tissue. Multiple copy number variations (CNVs) were mainly identified in CSF cfDNA, and MET copy number gain identified in 47.8% (11/23) of patients was the most frequent one, while other CNVs included ERBB2, KRAS, ALK, and MYC. Moreover, loss of heterozygosity (LOH) of TP53 was identified in 73.1% (19/26) CSF cfDNA, which was much higher than that in plasma (2/26, 7.7%; P < 0.001). There was a trend towards a higher frequency of concomitant resistance mutations in patients with TP53 LOH than those without (70.6% versus 33.3%; P = 0.162). EGFR T790M was identified in CSF cfDNA of 30.4% (7/23) of patients who experienced TKI progression.ConclusionCSF cfDNA could reveal the unique genetic profiles of LM and should be considered as the most representative liquid biopsy medium for LM in EGFR-mutant NSCLC.     

Benefit of Targeted DNA Sequencing in Advanced Non–Small-Cell Lung Cancer Patients Without EGFR and ALK Alterations on Conventional Tests

BackgroundGenetic sequencing testing has become widely used to inform treatment decisions for advanced non–small-cell lung cancer (NSCLC) patients. We analyzed benefits of genetic sequencing testing in real practice.Patients and MethodsWe retrospectively reviewed 209 NSCLC patients who had no EGFR and ALK alterations on routine molecular tests and underwent next-generation targeted DNA sequencing of 380 cancer-related genes between November 2013 and October 2016. Median patient age was 59 years. A total of 96 patients (46%) were never smokers, and 195 patients (93%) had adenocarcinoma.ResultsAmong 209 total patients, 64 (31%) demonstrated actionable genetic alterations; 20 had EGFR mutations (6 L858R, 8 exon 19 deletions, 1 L861Q, 1 G719S, 4 exon 20 duplications), 4 ALK fusions, 9 ROS1 fusions, 6 BRAF V600E mutations, 15 RET fusions, 1 MET high-level amplification, 6 MET exon 14 skipping mutations, and 3 ERBB2 exon 20 insertion mutations. Of the 64 patients harboring actionable alterations, 28 patients received therapy targeted to their own actionable alterations (15 EGFR, 3 ALK, 1 ROS1, 8 RET, 1 BRAF). There were significant differences in overall survival between individuals with no actionable alterations, those with actionable alterations but no targeted therapy, and those with actionable alterations and targeted therapy (20.1 vs. 17.1 vs. 66.2 months, P < .001).ConclusionThe results of targeted DNA sequencing testing could provide improved treatment options for some NSCLC patients and result in a survival benefit to NSCLC patients with no EGFR and ALK alterations on routine tests who are treated with targeted therapy.     

Phase I study of the HER3-targeted antibody patritumab (U3-1287) combined with erlotinib in Japanese patients with non-small cell lung cancer

ObjectivesHuman epidermal growth factor receptor 3 (HER3) is a key dimerization partner for HER family members and is associated with resistance to other HER family receptor-targeted therapeutics. This study evaluated the safety, tolerability, pharmacokinetics and efficacy of patritumab (U3-1287), a fully human anti-HER3 monoclonal antibody, in combination with erlotinib, an epidermal growth factor receptor-tyrosine kinase inhibitor in patients with previously treated advanced non-small cell lung cancer (NSCLC).Patients and methodsThis study enrolled patients with stage IIIB/IV NSCLC with Eastern Cooperative Oncology Group performance status 0–1, life expectancy >3 months and who had progressed after at least one prior course of chemotherapy (excluding erlotinib). This open-label study included two parts: dose escalation (Part 1) and dose expansion (Part 2). In Part 1, patients received intravenous patritumab 9 or 18 mg/kg every 3 weeks in addition to per-oral erlotinib 150 mg/day daily. In Part 2, patients received the recommended dose of patritumab as determined in Part 1. Adverse event rates, pharmacokinetics and tumor responses were determined.ResultsTwenty-four Japanese patients received patritumab at 9 mg/kg (n = 3) or 18 mg/kg (n = 21), and erlotinib. No dose-limiting toxicities were reported, indicating the maximum-tolerated dose was not reached. The most frequent adverse events were gastrointestinal or skin toxicities, which were generally mild and manageable. Patritumab pharmacokinetics were similar to those reported in previous studies. The median progression-free survival (95% confidence interval) was 44.0 (22.0–133.0) days for the EGFR wild-type group (n = 9) and 107.0 (74.0–224.0) days for the EGFR-activating mutation group (n = 13). Evaluation of biomarkers by immunohistochemical analysis did not indicate a relationship between efficacy and HER3 expression in tumor tissues.ConclusionPatritumab in combination with erlotinib was well tolerated and the efficacy of the combination was encouraging, especially in patients where prior gefitinib treatment failed.     

Impact of TP53 mutation status on systemic treatment outcome in ALK-rearranged non-small-cell lung cancer

BackgroundWe analyzed whether co-occurring mutations influence the outcome of systemic therapy in ALK-rearranged non-small-cell lung cancer (NSCLC).Patients and methodsALK-rearranged stage IIIB/IV NSCLC patients were analyzed with next-generation sequencing and fluorescence in situ hybridization analyses on a centralized diagnostic platform. Median progression-free survival (PFS) and overall survival (OS) were determined in the total cohort and in treatment-related sub-cohorts. Cox regression analyses were carried out to exclude confounders.ResultsAmong 216 patients with ALK-rearranged NSCLC, the frequency of pathogenic TP53 mutations was 23.8%, while other co-occurring mutations were rare events. In ALK/TP53 co-mutated patients, median PFS and OS were significantly lower compared with TP53 wildtype patients [PFS 3.9 months (95% CI: 2.4–5.6) versus 10.3 months (95% CI: 8.6–12.0), P < 0.001; OS 15.0 months (95% CI: 5.0–24.9) versus 50.0 months (95% CI: 22.9–77.1), P = 0.002]. This difference was confirmed in all treatment-related subgroups including chemotherapy only [PFS first-line chemotherapy 2.6 months (95% CI: 1.3–4.1) versus 6.2 months (95% CI: 1.8–10.5), P = 0.021; OS 2.0 months (95% CI: 0.0–4.6) versus 9.0 months (95% CI: 6.1–11.9), P = 0.035], crizotinib plus chemotherapy [PFS crizotinib 5.0 months (95% CI: 2.9–7.2) versus 14.0 months (95% CI: 8.0–20.1), P < 0.001; OS 17.0 months (95% CI: 6.7–27.3) versus not reached, P = 0.049] and crizotinib followed by next-generation ALK-inhibitor [PFS next-generation inhibitor 5.4 months (95% CI: 0.1–10.7) versus 9.9 months (95% CI: 6.4–13.5), P = 0.039; OS 7.0 months versus 50.0 months (95% CI: not reached), P = 0.001).ConclusionsIn ALK-rearranged NSCLC co-occurring TP53 mutations predict an unfavorable outcome of systemic therapy. Our observations encourage future research to understand the underlying molecular mechanisms and to improve treatment outcome of the ALK/TP53 co-mutated subgroup.     

Primary tumor sidedness and benefit from FOLFOXIRI plus bevacizumab as initial therapy for metastatic colorectal cancer. Retrospective analysis of the TRIBE trial by GONO

BackgroundRight-sided metastatic colorectal cancer (mCRC) patients have poor prognosis and achieve limited benefit from first-line doublets plus a targeted agent. In this unplanned analysis of the TRIBE study, we investigated the prognostic and predictive impact of primary tumor sidedness in mCRC patients and the differential impact of the intensification of the chemotherapy in subgroups defined according to both primary tumor sidedness and RAS and BRAF mutational status.Patients and methodsPatients were randomized to receive upfront 5-fluoruracil, leucovorin, and irinotecan (FOLFIRI) plus bevacizumab or 5-fluoruracil, leucovorin, oxaliplatin, and irinotecan (FOLFOXIRI) plus bevacizumab. Tumors were defined as right- or left-sided if they originated from the caecum to the transverse colon or within the splenic flexure and beyond, respectively. Patients with available information about both primary sidedness and RAS and BRAF status were included in the present analysis. Progression-free survival (PFS), overall survival (OS) and RECIST response rate were assessed according to tumor location and RAS and BRAF mutational status.ResultsInformation about primary sidedness and RAS and BRAF status was available for 358 (70.5%) out of 508 randomized patients. Patients with right-sided tumors (N = 173) presented shorter OS [23.7 versus 31.0 months, HR = 1.42 (95% CI 1.09–1.84), P = 0.010] and a trend toward shorter PFS [10.2 versus 11.5 months, HR = 1.24 (95% CI: 0.98–1.56), P = 0.083] than those with left-sided tumors (N = 185), but these associations were no longer evident when adjusting for RAS and BRAF status. Patients with right-sided tumors achieved more relative benefit from the intensification of the chemotherapy backbone in terms of both PFS (HR = 0.59 versus 0.89, P for interaction = 0.099) and OS (HR = 0.56 versus 0.99, P for interaction = 0.030) and this advantage was independent of their RAS and BRAF status.ConclusionsFOLFOXIRI plus bevacizumab may be regarded as a preferred first-line treatment option for clinically selected patients with right-sided metastatic colorectal cancer irrespective of their RAS and BRAF mutational status. Trial registration: clinicaltrials.gov identifier NCT00719797.     

Effect of docetaxel duration on clinical outcomes: exploratory analysis of CLEOPATRA,a phase III randomized controlled trial

BackgroundCombination pertuzumab, trastuzumab, and docetaxel (D) is considered standard first-line treatment of human epidermal growth factor receptor 2 (HER2)-positive metastatic breast cancer. This post hoc, exploratory analysis of CLEOPATRA study data evaluated the clinical effects of D treatment duration within this regimen. The clinical benefits of pertuzumab and trastuzumab by different durations of D treatment were also evaluated.Patients and methodsPatients with HER2-positive metastatic breast cancer received trastuzumab and D plus pertuzumab or placebo. Clinical outcomes were analyzed by the number of D cycles that patients received (<6D, 6D, or >6D). Progression-free survival (PFS) and overall survival (OS) for each treatment arm within each D cycle group were estimated using the Kaplan–Meier approach. Time-dependent, multivariate Cox regression was applied to estimate adjusted hazard ratios (HRs) and 95% confidence intervals (CIs) for HER2-targeted therapy and D cycle groups.ResultsOverall, 804 patients received <6D (n = 119), 6D (n = 210), or >6D (n = 475) cycles. After adjusting for pertuzumab benefits versus placebo (PFS HR = 0.61, 95% CI 0.51–0.74, P < 0.0001; OS HR = 0.60, 95% CI, 0.49–0.74, P < 0.0001), >6D versus 6D cycles was not associated with statistically significant improvements in PFS (HR = 0.80, 95% CI 0.63–1.01, P = 0.0640) or OS (HR = 0.88, 95% CI 0.69–1.12, P = 0.3073). Consistent improvements in PFS and OS were observed with pertuzumab versus placebo, irrespective of D duration. The HRs for PFS were 0.395, 0.615, and 0.633 for <6D, 6D, and >6D cycles, respectively (P < 0.05 for all D cycle groups). Corresponding HRs for OS were 0.577, 0.700, and 0.612, respectively (P < 0.05 for <6D and >6D).ConclusionsAfter accounting for pertuzumab benefits, more than six cycles of D treatment was not associated with significant improvements in either PFS or OS compared with six cycles. The addition of pertuzumab to trastuzumab improved clinical outcomes versus trastuzumab plus placebo, regardless of D treatment duration.ClinicalTrials.gov identifierNCT00567190.     

CMS-dependent prognostic impact of KRAS and BRAFV600E mutations in primary colorectal cancer

BackgroundThe prognostic impact of KRAS and BRAF^V600E mutations in primary colorectal cancer (CRC) varies with microsatellite instability (MSI) status. The gene expression–based consensus molecular subtypes (CMSs) of CRC define molecularly and clinically distinct subgroups, and represent a novel stratification framework in biomarker analysis. We investigated the prognostic value of these mutations within the CMS groups.Patients and methodsTotally 1197 primary tumors from a Norwegian series of CRC stage I–IV were analyzed for MSI and mutation status in hotspots in KRAS (codons 12, 13 and 61) and BRAF (codon 600). A subset was analyzed for gene expression and confident CMS classification was obtained for 317 samples. This cohort was expanded with clinical and molecular data, including CMS classification, from 514 patients in the publically available dataset GSE39582. Gene expression signatures associated with KRAS and BRAF^V600E mutations were used to evaluate differential impact of mutations on gene expression among the CMS groups.ResultsBRAF^V600E and KRAS mutations were both associated with inferior 5-year overall survival (OS) exclusively in MSS tumors (BRAF^V600E mutation versus KRAS/BRAF wild-type: Hazard ratio (HR) 2.85, P < 0.001; KRAS mutation versus KRAS/BRAF wild-type: HR 1.30, P = 0.013). BRAF^V600E-mutated MSS tumors were strongly enriched and associated with metastatic disease in CMS1, leading to negative prognostic impact in this subtype (OS: BRAF^V600E mutation versus wild-type: HR 7.73, P = 0.001). In contrast, the poor prognosis of KRAS mutations was limited to MSS tumors with CMS2/CMS3 epithelial-like gene expression profiles (OS: KRAS mutation versus wild-type: HR 1.51, P = 0.011). The subtype-specific prognostic associations were substantiated by differential effects of BRAF^V600E and KRAS mutations on gene expression signatures according to the MSI status and CMS group.ConclusionsBRAF^V600E mutations are enriched and associated with metastatic disease in CMS1 MSS tumors, leading to poor prognosis in this subtype. KRAS mutations are associated with adverse outcome in epithelial (CMS2/CMS3) MSS tumors.     

Clinical Outcome With Platinum-Based Chemotherapy in Patients With Advanced Nonsquamous EGFR Wild-Type Non–Small-Cell Lung Cancer Segregated According to KRAS Mutation Status

BackgroundWe hypothesized that KRAS mutations function as a marker of poor sensitivity to first-line platinum-based chemotherapy in patients with advanced nonsquamous EGFR wild-type (WT) non–small-cell lung cancer (NSCLC).Patients and MethodsConsecutive advanced nonsquamous EGFR WT NSCLCs treated at the Medical Oncology of Perugia with simultaneous assessment of KRAS mutation status were eligible. Anaplastic lymphoma kinase (ALK) gene status was known in roughly half of the patients who had KRAS WT.ResultsTwo hundred four patients were included. Among them, the 77 individuals carrying a KRAS-mutant phenotype experienced a significantly inferior outcome in terms of response rate (P = .04), disease control rate (P = .05), and progression-free survival (PFS) (P = .05) compared with the EGFR WT/KRAS WT population. The association between KRAS mutation and shorter PFS remained statistically significant at multivariate analysis (hazard ratio [HR], 1.45). In addition, patients with KRAS mutations reported a significantly shorter overall survival (OS) compared with patients with EGFR WT/KRAS WT/ALK negativity (n = 64) (P = .02). Among patients with KRAS mutations, those harboring a mutation at codon 13 (n = 12) performed worse than those with a mutation at codon 12 (n = 62) in terms of both PFS and OS (P = .09 for both).ConclusionKRAS mutation appears to negatively affect sensitivity to first-line platinum-based chemotherapy in patients with advanced nonsquamous EGFR WT NSCLC. Studies on larger case series are needed to address differences in clinical outcome according to the type of mutation.     

Subtypes of EGFR- and HER2-Mutant Metastatic NSCLC Influence Response to Immune Checkpoint Inhibitors

IntroductionThe efficacy of immune checkpoint inhibitors (ICIs) is low among EGFR-mutated non–small-cell lung cancer (NSCLC), although prolonged responses have occasionally been reported. We investigated the association between mutation subtypes and ICI outcomes among HER2- and EGFR-mutated NSCLC.Patients and MethodsThis retrospective single-center study analyzed patients with EGFR- and HER2-mutated advanced NSCLC who received at least 1 cycle of ICI between 2013 and 2019. Patient characteristics, mutation subtype, and ICI outcomes.ResultsAmong 48 patients with advanced NSCLC, 14 (29%) had HER2 mutations and 34 (71%) had EGFR mutations. EGFR mutations included 16 (47%) exon 19 deletion, 7 (21%) L858R, 5 (15%) uncommon, and 6 (18%) exon 20 insertion. Compared to EGFR-sensitizing mutations (ESMs), HER2 and EGFR exon 20 mutations were associated with a trend toward better response (respectively, ESM, HER2, and EGFR exon 20: 11%, 29%, and 50%; P = .07) and significantly better disease control rates (respectively, 18%, 57%, and 67%; P = .008). Compared to ESM, HER2 mutations (adjusted hazard ratio, 0.35; P = .02) and EGFR exon 20 mutations (adjusted hazard ratio, 0.37; P = .10 trend) were also associated with improved PFS. Programmed death ligand 1 (PD-L1) expression remained an independent predictor of PFS (adjusted hazard ratio, 0.42; 95% confidence interval, 0.23-0.76; P = .004). The 6-month PFS rates were 29% (HER2), 33% (EGFR exon 20), and 4% (ESM). ICIs were generally well tolerated in this population. Importantly, no immune-related toxicity was observed in 10 patients who received a tyrosine kinase inhibitor (TKI) as the immediate next line treatment after ICI.ConclusionHER2 and EGFR exon 20 mutations derive greater benefit from ICIs with comparable PFS to wild-type historical second/third-line unselected cohorts. ICIs remain a treatment option for this genomic subgroup, given the absence of approved targeted therapies for these rare mutations.     

A prospective examination of circulating tumor cell profiles in non-small-cell lung cancer molecular subgroups

BackgroundWe report the first study examining the clinical, numerical and biological properties of circulating tumor cells according to molecular subtypes of non-small-cell lung cancer.Patients and methods125 patients with treatment-naïve stage IIIb-IV NSCLC were prospectively recruited for CellSearch analysis. Anti-vimentin antibody was included for examination of CTCs to assess their mesenchymal character. Associations of total CTCs and vimentin-positive (vim +) CTCs with clinical characteristics, tumor genotype, and survival were assessed.Results51/125 patients (40.8%) were total CTC+ and 26/125 (20.8%) were vim CTC+ at baseline. Multivariate analysis showed patients with ≥5 total CTCs had significantly reduced OS (HR 0.55, 95% CI 0.33–0.92, P = 0.022) but not PFS (HR 0.68, 95% CI 0.42–1.1, P = 0.118) compared to patients with <5 total CTCs. No OS difference was evident between vim+ CTC and vim-negative CTC patients overall (HR 1.24, 95% CI 0.67–2.28, P = 0.494), but after subdivision according to NSCLC driver mutation, we found an increase of vim+ CTCs in the EGFR-mutated subgroup (N = 21/94 patients; mean 1.24 vs 1.22 vim+ CTCs, P = 0.013), a reduction of total CTCs in the ALK-rearranged subgroup (N = 13/90 patients; mean 1.69 vs 5.82 total CTCs, P = 0.029), and a total absence of vim+ CTCs in KRAS-mutated adenocarcinomas (N = 19/78 patients; mean 0 vs 1.4 vim+ CTCs, P = 0.006).ConclusionsWe validate that the baseline presence of ≥5 total CTCs in advanced NSCLC confers a poor prognosis. CTCs from EGFR-mutant NSCLC express epithelial–mesenchymal transition characteristics, not seen in CTCs from patients with KRAS-mutant adenocarcinoma.     

PD-L1 expression,tumor mutational burden,and response to immunotherapy in patients with MET exon 14 altered lung cancers

BackgroundMET exon 14 alterations are actionable oncogenic drivers. Durable responses to MET inhibitors are observed in patients with advanced MET exon 14-altered lung cancers in prospective trials. In contrast, the activity of immunotherapy, PD-L1 expression and tumor mutational burden (TMB) of these tumors and are not well characterized.Patients and methodsPatients with MET exon 14-altered lung cancers of any stage treated at two academic institutions were identified. A review of clinicopathologic and molecular features, and an analysis of response to single-agent or combination immune checkpoint inhibition were conducted. PD-L1 immunohistochemistry was carried out and TMB was calculated by estimation from targeted next-generation sequencing panels.ResultsWe identified 147 patients with MET exon 14-altered lung cancers. PD-L1 expression of 0%, 1%–49%, and ≥50% were 37%, 22%, and 41%, respectively, in 111 evaluable tumor samples. The median TMB of MET exon 14-altered lung cancers was lower than that of unselected non-small-cell lung cancers (NSCLCs) in both independently evaluated cohorts: 3.8 versus 5.7 mutations/megabase (P < 0.001, n = 78 versus 1769, cohort A), and 7.3 versus 11.8 mutations/megabase (P < 0.001, n = 62 versus 1100, cohort B). There was no association between PD-L1 expression and TMB (Spearman’s rho=0.18, P = 0.069). In response-evaluable patients (n = 24), the objective response rate was 17% (95% CI 6% to 36%) and the median progression-free survival was 1.9 months (95% CI 1.7–2.7). Responses were not enriched in tumors with PD-L1 expression ≥50% nor high TMB.ConclusionA substantial proportion of MET exon 14-altered lung cancers express PD-L1, but the median TMB is lower compared with unselected NSCLCs. Occasional responses to PD-1 blockade can be achieved, but overall clinical efficacy is modest.