A landmark point analysis with cytotoxic agents for advanced NSCLC

Making the Rounds: Exploring the Role of Circulating Tumor DNA (ctDNA) in Non-Small Cell Lung Cancer

Advancements in the clinical practice of non-small cell lung cancer (NSCLC) are shifting treatment paradigms towards increasingly personalized approaches. Liquid biopsies using various circulating analytes provide minimally invasive methods of sampling the molecular content within tumor cells. Plasma-derived circulating tumor DNA (ctDNA), the tumor-derived component of cell-free DNA (cfDNA), is the most extensively studied analyte and has a growing list of applications in the clinical management of NSCLC. As an alternative to tumor genotyping, the assessment of oncogenic driver alterations by ctDNA has become an accepted companion diagnostic via both single-gene polymerase chain reactions (PCR) and next-generation sequencing (NGS) for advanced NSCLC. ctDNA technologies have also shown the ability to detect the emerging mechanisms of acquired resistance that evolve after targeted therapy. Furthermore, the detection of minimal residual disease (MRD) by ctDNA for patients with NSCLC after curative-intent treatment may serve as a prognostic and potentially predictive biomarker for recurrence and response to therapy, respectively. Finally, ctDNA analysis via mutational, methylation, and/or fragmentation multi-omic profiling offers the potential for improving early lung cancer detection. In this review, we discuss the role of ctDNA in each of these capacities, namely, for molecular profiling, treatment response monitoring, MRD detection, and early cancer detection of NSCLC.

Progression-Free Survival, Response Rate, and Disease Control Rate as Predictors of Overall Survival in Phase III Randomized Controlled Trials Evaluating the First-Line Chemotherapy for Advanced, Locally Advanced, and Recurrent Non-Small Cell Lung Carcinoma

INTRODUCTION

Recent improvements in chemotherapy agents have prolonged postprogression survival of non-small cell lung cancer. Thus, primary outcomes other than overall survival (OS) have been frequently used for recent phase III trials to obtain quick results. However, no systematic review had assessed whether progression-free survival (PFS), response rate (RR), and disease control rate (DCR) can serve as surrogates for OS at the trial level in the phase III first-line chemotherapy setting.

METHODS

We included phase III randomized clinical trials (RCTs) comparing two arms that were reported as a full article regardless of their primary end point. We included only RCTs that evaluated chemonaive patients with advanced, locally advanced, or metastatic non-small cell lung cancer and were published after January 1, 2005. We systematically searched four public electronic databases. Two investigators independently screened and scrutinized candidate articles. How surrogate outcomes represented hazard ratios (HRs) for OS was examined.

RESULTS

Among 1907 articles, we ultimately found 44 eligible articles covering 22,709 subjects. HR for PFS, median PFS in the experimental arm minus median PFS in the control arm in months, OR for RR (ORrr), and OR for DCR were evaluated in 34, 35, 44, and 35 RCTs, respectively. HR for OS (HRos), median PFS in the experimental arm minus median PFS in the control arm, ORrr, and OR for DCR had weighted Spearman's rank correlation coefficients with an HRos of 0.496, 0.477, 0.570, and 0.470, respectively; the standardized weighted regression coefficients were 0.439, -0.376, -0.605, and -0.381, respectively; and the adjusted weighted coefficients of determination were 0.224, 0.161, 0.350, and 0.176, respectively.

CONCLUSIONS

ORrr, followed by HRpfs, had the strongest association with HRos at the trial level. However, these measures were not strong enough to replace OS.

Similar survival benefits of a good response and stable disease to platinum-based chemotherapy in non-small cell lung cancer

The present study aimed to evaluate the similar survival benefits of a good response [complete response or partial response (CR/PR)] and stable disease (SD) to chemotherapy in non-small cell lung cancer (NSCLC) patients in clinical practice. All 322 patients who were treated between 1999 and 2012 with first-line platinum-based chemotherapy were retrospectively analyzed. Tumor responses were classified according to the response evaluation criteria for solid tumors. A total of 67 (20.8%) patients experienced CR/PR and 165 (51.2%) achieved SD. There was no difference in progression-free survival between the patients with CR/PR and those with SD (P=0.347). There was also no difference between the two groups with regard to overall survival time (P=0.878). In multivariate analysis, disease-control (more than SD) was one of the favorable prognostic factors. In clinical practice, a survival benefit would be provided not only for the patients who have good response, but also for those with SD.

Impact of the first tumor response at eight weeks on overall survival in metastatic breast cancer patients treated with first-line combination chemotherapy

The aim of this was to determine whether the change of size observed at the first response evaluation after initiation of first-line combination chemotherapy correlates with overall survival (OS) in patients with metastatic breast cancer (MBC). The change in size of tumors derived from measurements according to Response Evaluation Criteria In Solid Tumors (RECIST) at the first evaluation on computed tomography (CT) was obtained from a multicenter, randomized phase III trial ("TEX trial," n = 287) comparing treatment with a combination of epirubicin and paclitaxel alone or with capecitabine (TEX). Cox regression and Kaplan-Meier analyses were performed to evaluate the correlations between the first change in tumor size, response according to RECIST and OS. Data from CT evaluations of 233 patients were available. Appearance of new lesions or progression of non-target lesions (new/non-target) indicated short OS by univariable regression analysis (HR 3.76, 95 % CI 1.90-7.42, p < 0.001). A decrease by >30 % at this early time point was prognostic favorable (HR 0.69, 95 % CI 0.49-0.98, p = 0.04) and not significantly less than the best overall response according to RECIST. After adjustment for previous adjuvant treatment and the treatment given within the frame of the randomized trial, OS was still significantly shorter in patients with new/non-target lesions after a median 8 weeks of treatment (HR 4.41, 95 % CI 2.74-7.11, p < 0.001). Disease progression at the first evaluation correlates with OS in patients with MBC treated with first-line combination chemotherapy. The main reason for early disease progression was the appearance of new lesions or progression of non-target lesions. These patients had poor OS even though more lines of treatment were available. Thus, these factors should be focused on in the response evaluations besides tumor size changes.

Soluble Human Epidermal Growth Factor Receptor 2 (sHER2) as a Potential Risk Assessment, Screening, and Diagnostic Biomarker of Lung Adenocarcinoma

Lung cancer is the leading cause of cancer-related death in the United States. Here, we evaluated the potential clinical utility of soluble human epidermal growth factor receptor 2 (sHER2) for the risk assessment, screening, and diagnosis of non-small cell lung cancer (NSCLC) using an unmatched case-control study design. Serum sHER2 concentrations were measured by immunoassay in 244 primary NSCLC cases and 218 healthy controls. Wilcoxon rank-sum tests, logistic regression models, and receiver operating characteristic plots were used to assess whether sHER2 is associated with lung cancer. Median serum sHER2 concentrations are higher in patients with adenocarcinoma than squamous cell carcinoma regardless of gender, and sHER2 is a weak, independent biomarker of adenocarcinoma, but not of squamous cell carcinoma, adjusted for age and gender. The age-adjusted relative risk (odds) of adenocarcinoma is 3.95 (95% CI: 1.22, 12.81) and 7.93 (95% CI: 2.26, 27.82) greater for women and men with high sHER2 concentrations (≥6.60 ng/mL) vs. low sHER2 concentrations (≤1.85 ng/mL), respectively. When adjusted for each other, sHER2, age, and gender discern healthy controls from patients with primary adenocarcinomas of the lung with 85.9% accuracy. We conclude that even though serum sHER2 is not a strong, stand-alone discriminatory biomarker of adenocarcinoma, sHER2 may be a useful, independent covariate in multivariate risk assessment, screening, and diagnostic models of lung cancer.