Sort by
Managing Acquired Resistance to Third-Generation EGFR Tyrosine Kinase Inhibitors Through Co-Targeting MEK/ERK Signaling

Although epidermal growth factor receptor (EGFR)-targeted therapy has improved clinical outcomes of patients with advanced non-small-cell lung cancer (NSCLC) carrying activating EGFR mutations, the development of acquired resistance to EGFR tyrosine kinase inhibitors (EGFR-TKIs), including the promising third-generation ones, results in disease progression and has become an unavoidable problem that limits patient long-term benefit. The third-generation EGFR-TKIs, osimertinib and almonertinib, are now approved for the treatment of advanced NSCLC patients harboring activating EGFR mutations (first-line) and/or the resistant T790M mutation (second-line). Clinically, appropriate management of acquired resistance to third-generation EGFR-TKIs will substantially improve their long-term efficacy against EGFR-mutant NSCLC. Recent preclinical and clinical studies suggest that activation of the Ras/Raf/MEK/ERK signaling pathway may be an important resistance mechanism and accordingly co-targeting this pathway effectively overcomes and abrogates acquired resistance to third-generation EGFR-TKIs. This review focuses on discussing the scientific rationale for and potential of co-targeting MEK/ERK signaling in delaying and overcoming acquired resistance to third-generation EGFR-TKIs, particularly osimertinib.

Open Access
Relevant
Clinical outcomes following advanced respiratory motion management (respiratory gating or dynamic tumor tracking) with stereotactic body radiation therapy for stage I non-small-cell lung cancer

PurposeTo report the outcomes of stereotactic body radiation therapy (SBRT) for stage I non-small-cell lung cancer (NSCLC) according to respiratory motion management method.MethodsPatients with stage I NSCLC who received SBRT from 2007 to 2015 were reviewed. Computed tomography (CT) simulation with four-dimensional CT was performed for respiratory motion assessment. Tumor motion >1 cm in the craniocaudal direction was selectively treated with advanced respiratory management: either respiratory gating to a pre-specified portion of the respiratory cycle or dynamic tracking of an implanted fiducial marker. Comparisons were made with internal target volume approach, which treated all phases of respiratory motion.ResultsOf 297 patients treated with SBRT at our institution, 51 underwent advanced respiratory management (48 with respiratory gating and three with tumor tracking) and 246 underwent all-phase treatment. Groups were similarly balanced with regard to mean age (P=0.242), tumor size (P=0.315), and histology (P=0.715). Tumor location in the lower lung lobes, as compared to middle or upper lobes, was more common in those treated with advanced respiratory management (78.4%) compared to all-phase treatment (25.6%, P<.0001). There were 17 local recurrences in the treated lesions. Kaplan–Meier analyses showed that there were no differences with regard to mean time to local failure (91.5 vs 98.8 months, P=0.56), mean time to any failure (73.2 vs 78.7 months, P=0.73), or median overall survival (43.3 vs 45.5 months, P=0.56) between patients who underwent advanced respiratory motion management and all-phase treatment.ConclusionSBRT with advanced respiratory management (the majority with respiratory gating) showed similar efficacy to all-phase treatment approach for stage I NSCLC.

Open Access
Relevant
Silicosis and lung cancer: current perspectives

“Silica” refers to crystalline particles formed by the combination of silicon with oxygen. Inhalation of silica particles promotes the development of pulmonary fibrosis that over prolonged periods increases the risk of lung cancer. The International Agency for Research on Cancer (IARC) classified crystalline silica as a human carcinogen in 1997. This categorization was questioned due to 1) the absence of dose–response findings, 2) the presence of confounding variables that complicated interpretation of the data and 3) potential selection bias for compensated silicosis. Yet, recent epidemiologic studies strongly support the conclusion that silica exposure increases the risk of lung cancer in humans independent of confounding factors including cigarette smoke. Based on this evidence, the US Occupational Safety and Health Administration (OSHA) lowered the occupational exposure limit for crystalline silica from 0.1 to 0.05 mg/m3 in 2013. Further supporting the human epidemiologic data, murine models show that chronic silicosis is associated with an increased risk of lung cancer. In animals, the initial inflammation induced by silica exposure is followed by the development of an immunosuppressive microenvironment that supports the growth of lung tumors. This work will review our current knowledge of silica-associated lung cancers, highlighting how recent mechanistic insights support the use of cutting-edge approaches to diagnose and treat silica-related lung cancer.

Open Access
Relevant
Uncommon &lt;em&gt;EGFR&lt;/em&gt; mutations in cytological specimens of 1,874 newly diagnosed Indonesian lung cancer patients

PurposeWe aimed to evaluate the distribution of individual epidermal growth factor receptor (EGFR) mutation subtypes found in routine cytological specimens.Patients and methodsA retrospective audit was performed on EGFR testing results of 1,874 consecutive cytological samples of newly diagnosed or treatment-naïve Indonesian lung cancer patients (years 2015–2016). Testing was performed by ISO15189 accredited central laboratory.ResultsOverall test failure rate was 5.1%, with the highest failure (7.1%) observed in pleural effusion and lowest (1.6%) in needle aspiration samples. EGFR mutation frequency was 44.4%. Tyrosine kinase inhibitor (TKI)-sensitive common EGFR mutations (ins/dels exon 19, L858R) and uncommon mutations (G719X, T790M, L861Q) contributed 57.1% and 29%, respectively. Approximately 13.9% of mutation-positive patients carried a mixture of common and uncommon mutations. Women had higher EGFR mutation rate (52.9%) vs men (39.1%; p<0.05). In contrast, uncommon mutations conferring either TKI responsive (G719X, L861Q) or TKI resistance (T790M, exon 20 insertions) were consistently more frequent in men than in women (67.3% vs 32.7% or 69.4% vs 30.6%; p<0.05). Up to 10% EGFR mutation–positive patients had baseline single mutation T790M, exon 20 insertion, or in coexistence with TKI-sensitive mutations. Up to 9% patients had complex or multiple EGFR mutations, whereby 48.7% patients harbored TKI-resistant mutations. One patient presented third-generation TKI-resistant mutation L792F simultaneously with T790M.ConclusionRoutine diagnostic cytological techniques yielded similar success rate to detect EGFR mutations. Uncommon EGFR mutations were frequent events in Indonesian lung cancer patients.

Open Access
Relevant
Pretreatment Glasgow prognostic score and prognostic nutritional index predict overall survival of patients with advanced small cell lung cancer

BackgroundVarious biomarkers have been shown to predict prognosis in various types of cancers. However, these biomarkers have not been studied in advanced small cell lung cancer (SCLC). The modified Glasgow prognostic score (mGPS) is based on serum albumin level and C-reactive protein (CRP). The prognostic nutritional index (PNI) is a combination of serum albumin level and absolute lymphocyte count. This study aimed to evaluate the prognostic value of mGPS and PNI in SCLC.MethodsWe retrospectively reviewed and calculated mGPS and PNI for patients with stage IIIB or IV SCLC who initiated platinum-based combination chemotherapy between November 2007 and June 2016. We compared overall survival (OS) and progression-free survival (PFS) between high and low groups of these two biomarkers. Univariate and multivariate Cox hazard analyses assessed the prognostic value of these biomarkers.ResultsWe reviewed 97 SCLC patients. The OS of patients with mGPS 0–1 and higher PNI was significantly longer than that of those with mGPS 2 and lower PNI. The PFS of mGPS 0–1 was significantly longer than that of mGPS 2, while there was no significant difference in PFS according to PNI. Multivariate analyses found mGPS 0–1 (hazard ratio [HR] 2.34, 95% confidence interval [CI] 1.27–4.31, P<0.01) and higher PNI (HR 0.50, 95% CI 0.31–0.78, P<0.01) as prognostic factors for longer OS. However, neither biomarker was predictive of PFS.ConclusionOur study was a small retrospective study; however, the data demonstrate that pretreatment mGPS and PNI are independent predictors of OS in patients with advanced SCLC. The pretreatment assessment of mGPS and PNI may be useful for identification of patients with poor prognosis. We recommend pretreatment measurement of serum albumin, C-reactive protein, and absolute lymphocyte count.

Open Access
Relevant
65Plus: open-label study of bevacizumab in combination with pemetrexed or pemetrexed/carboplatin as first-line treatment of patients with advanced or recurrent nonsquamous non-small-cell lung cancer

BackgroundThe aim of the study was to investigate in terms of noninferiority the efficacy and safety of a monochemotherapy regimen of pemetrexed plus bevacizumab (BevPem) versus carboplatin/pemetrexed plus bevacizumab (BevCPem) in elderly patients as first-line treatment for advanced metastatic or recurrent nonsquamous non-small-cell lung cancer (NSCLC).Materials and methods65Plus was a Phase III, randomized, open-label study. In total, 253 patients received BevPem (n=119) or BevCPem (n=134). The primary outcome measure was progression-free survival. Secondary end points were overall survival, tumor response, and safety outcomes. Evaluations were performed for the whole study population and stratified according to Eastern Cooperative Oncology Group (ECOG) performance status (PS).ResultsNoninferiority of BevPem in comparison to BevCPem could not be demonstrated for the overall population (P=0.7864). Significant superiority of the combined treatment BevCPem was seen in patients of ECOG PS 0–1 (median PFS 5.1 vs 6.9 months, HR 1.353, 95% CI 1.03–1.777), while the opposite tendency was observed in patients with ECOG PS 2 (median PFS 2.9 vs 1.5 months, HR 0.628, 95% CI 0.195–2.025). Overall, better tolerability was found for the BevPem group, irrespective of ECOG PS.ConclusionResults from the 65plus study give evidence that BevPem and BevCPem treatments may exert differential effects on PFS, depending on the patients ECOG PS. It appears that patients with better ECOG PS (0–1) benefited more from the combined treatment with carboplatin, while the group comprising more severely impaired patients (ECOG PS 2) benefited more from the monochemotherapy.

Open Access
Relevant
Outcomes and prognostic factors of chemotherapy for patients with locally advanced or metastatic pulmonary squamous cell carcinoma

BackgroundPulmonary squamous cell carcinoma has not benefited from improvements in chemotherapy over the past decade, compared with non-squamous non-small-cell lung cancer. Nowadays, treatment strategies differ between squamous and non-squamous non-small-cell lung cancers. This study aimed to investigate the percentage of patients treated with first-, second-, or third-line chemotherapy and the characteristics of patients for whom chemotherapy has been beneficial.MethodData on patients with stage IIIB or IV squamous cell carcinoma diagnosed between June 2007 and March 2015, and on patients who had received first-, second-, or third-line chemotherapy between June 2007 and November 2015 at our hospital, were retrospectively extracted from our institutional medical charts. We also compared patients who were treated with chemotherapy (chemotherapy group) and patients who were not (non-chemotherapy group) using multivariate logistic regression and multivariate Cox hazard analyses, respectively.ResultsDuring the study period, 103, 63, and 32 patients received first-, second-, and third-line chemotherapy, respectively. Fifty-one patients did not receive chemotherapy. Factors predicting unlikely chemotherapy included age ≥75 years, Eastern Cooperative Oncology Group (ECOG)-performance status (PS) ≥2, Charlson comorbidity index ≥2, hemoglobin <12.2 g/dL, red cell distribution width ≥13.9%, and serum sodium <140 mEq/L. Factors predicting survival for each line of chemotherapy included the following: ECOG-PS ≥2 for first-line; ECOG-PS ≥2 and lymphocyte count for second-line; and ECOG-PS ≥2, body mass index <18.5 kg/m2, and hemoglobin and lactate dehydrogenase levels for third-line.ConclusionApproximately 66% of patients received first-line chemotherapy. Of those, 66% and 33% received second- and third-line chemotherapy, respectively. ECOG-PS was always an essential prognostic factor when considering introducing chemotherapy and proceeding with additional chemotherapy. Other markers, such as lymphocyte count, body mass index, anemia, and lactate dehydrogenase level, may be useful depending on the patient and line of chemotherapy.

Open Access
Relevant