Correlation of progression-free and post-progression survival with overall survival in advanced colorectal cancer

Real-World Evidence of FOLFIRI Combined with Anti-Angiogenesis Inhibitors or Anti-EGFR Antibodies for Patients with Early Recurrence Colorectal Cancer After Adjuvant FOLFOX/CAPOX Therapy: A Japanese Claims Database Study

BACKGROUND

Oxaliplatin-containing adjuvant regimens (folinic acid, fluorouracil, and oxaliplatin/capecitabine and oxaliplatin [FOLFOX/CAPOX]) are used after curative resection of colorectal cancer (CRC). However, real-world evidence regarding treatment sequences and outcomes in patients with early recurrence CRC after adjuvant chemotherapy is limited.

OBJECTIVE

We aimed to describe the patient characteristics, treatment sequence, and overall duration of second-line (2L) therapy in patients with early recurrence CRC who received adjuvant chemotherapy (FOLFOX/CAPOX) followed by folinic acid, fluorouracil, and irinotecan (FOLFIRI) + anti-angiogenesis drugs (AA) or FOLFIRI + anti-epidermal growth factor receptor (EGFR) antibodies.

METHODS

This retrospective study analyzed Japanese administrative data from November 2014 to March 2023 of adult patients who underwent CRC resection surgery, started FOLFOX/CAPOX ≤3 months (mo) after surgery, and had early CRC recurrence. Early recurrence was defined as initiation of FOLFIRI+AA or FOLFIRI+anti-EGFR antibodies as 2L therapy, ≤12 mo of discontinuing adjuvant chemotherapy. Patient characteristics, treatment sequence, median time to treatment discontinuation (mTTD), i.e., duration between the start and end dates of 2L therapy (Kaplan-Meier method), and factors associated with 2L time to treatment discontinuation constituted the study outcomes (Cox regression model). Subgroup analyses were performed for timing of early CRC recurrence (≤6 mo and 6-12 mo) and tumor sidedness.

RESULTS

Among the 832 selected patients (median age [minimum-maximum] 67 (24-86) years, 56.4% male), CAPOX (71.3%) was more commonly used than FOLFOX (28.7%) as adjuvant therapy. FOLFIRI+AA (72.5%) was used more commonly than FOLFIRI+anti-EGFR antibodies (27.5%) in 2L. AA and anti-EGFR antibodies groups had similar mTTD: 6.2 mo (95% confidence interval 5.8, 6.9) and 6.1 mo (95% confidence interval 5.2, 7.4). Age ≥70 years showed significant association with shorter 2L treatment duration (hazard ratio 1.2, 95% confidence interval 1.0, 1.4; p = 0.03). The AA cohort's mTTD was numerically shorter in the ≤6 mo recurrence subgroup compared with the 6-12 mo recurrence subgroup (6.1 mo vs 8.1 mo); the anti-EGFR antibodies cohort had similar mTTD (5.8 mo vs 6.2 mo). The AA and anti-EGFR antibodies cohorts also had similar mTTD in the left-sided CRC subgroup (6.5 mo vs 6.2 mo), but not in the right-sided subgroup (5.6 mo vs 3.9 mo).

CONCLUSIONS

This is the first administrative data-based real-world evidence on treatment sequence and outcomes for patients with early recurrence CRC treated with FOLFIRI+AAs or FOLFIRI+ anti-EGFR antibodies after adjuvant FOLFOX/CAPOX therapy in Japan. Both regimens had similar TTD, but relapse timing and tumor sidedness may influence their efficacy.

Time-to-Event Endpoints in Imaging Biomarker Studies

Time-to-event endpoints are widely used as measures of patients' well-being and indicators of prognosis. In imaging-based biomarker studies, there are increasingly more studies that focus on examining imaging biomarkers' prognostic or predictive utilities on those endpoints, whether in a trial or an observational study setting. In this educational review article, we briefly introduce some basic concepts of time-to-event endpoints and point out potential pitfalls in the context of imaging biomarker research in hope of improving radiologists' understanding of related subjects. Besides, we have included some review and discussions on the benefits of using time-to-event endpoints and considerations on selecting overall survival or progression-free survival for primary analysis. LEVEL OF EVIDENCE: 5 TECHNICAL EFFICACY: Stage 3.

Real-World Data Analysis of Second-Line Antiangiogenic Targeted Treatments Following Anti-Epidermal Growth Factor Receptor Monoclonal Antibodies and First-Line FOLFOX for Patients with Metastatic Colorectal Cancer

Introduction

Evidence is lacking on second-line and later treatments for patients with RAS wild-type colorectal cancer (CRC) who receive first-line anti-epidermal growth factor receptor (EGFR) antibody therapy. In this study, we explored the real-world treatment sequences, treatment duration, and factors associated with treatment sequences and durations in Japanese patients with CRC.

Methods

This retrospective observational cohort study used a Japanese administrative claims database (April 2008 to July 2021). Patients with confirmed CRC (presumed RAS wild-type) who received first-line FOLFOX (leucovorin + 5-fluorouracil + oxaliplatin) plus anti-EGFR therapy in or after May 2016, followed by second-line irinotecan-based chemotherapy plus an antiangiogenic drug, were included. Treatment durations were estimated by the Kaplan–Meier method. Cox regression analysis was used to identify factors associated with treatment duration.

Results

Analysis populations consisted of 1163 (first-line and second-line) and 645 (third-line) patients. At the start of first-line therapy, 67.8% of patients were male, the mean age was 64 years, 83.4% had left-sided CRC, and 84.3% were prescribed FOLFOX plus panitumumab. For second-line therapy, patients were prescribed bevacizumab (63%), ramucirumab (27%), or aflibercept beta (10%). Median (95% CI) treatment durations from the start of second-line therapy to the end of antitumor drug therapies were similar for bevacizumab (12.5 months [11.2, 14.0]), ramucirumab (12.5 months [11.2, 14.8]), and aflibercept beta (14.0 months [10.4, 17.0]). Treatment duration from second-line was positively associated with first-line treatment duration of 6 months or more, CRC surgery before starting first-line therapy, and liver surgery during first-line therapy, and was negatively associated with use of nonsteroidal anti-inflammatory drugs before second-line therapy.

Conclusion

Real-world data revealed that all three antiangiogenic drugs were used as second-line therapy after first-line anti-EGFR antibodies and showed similar treatment durations.

Supplementary Information

The online version contains supplementary material available at 10.1007/s12325-022-02122-4.

Clinical impact of post-progression survival in patients with locally advanced non-small cell lung cancer after chemoradiotherapy

BACKGROUND

The efficacy of first-line chemoradiotherapy for overall survival (OS) might be confounded by the subsequent treatments in patients with locally advanced non-small cell lung cancer (NSCLC). In this study, we assessed the associations of progression-free survival (PFS) and post-progression survival (PPS) with OS after chemoradiotherapy for locally advanced NSCLC using patient-level data.

PATIENTS AND METHODS

Between January 2011 and December 2018, 45 patients with locally advanced NSCLC who had received first-line chemoradiotherapy and in whom recurrence occurred were analysed. The associations of PFS and PPS with OS were analysed at the individual level.

RESULTS

Linear regression and Spearman rank correlation analyses revealed that PPS was strongly correlated with OS (r = 0.72, p < 0.05, R2 = 0.54), whereas PFS was moderately correlated with OS (r = 0.58, p < 0.05, R² = 0.34). The Glasgow prognostic score and liver metastases at recurrence were significantly associated with PPS (p < 0.001).

CONCLUSIONS

The current analysis of individual-level data of patients treated with first-line chemoradiotherapy implied that PPS had a higher impact on OS than PFS in patients with locally advanced NSCLC. Additionally, current perceptions indicate that treatment beyond progression after first-line chemoradiotherapy might strongly affect OS.

Post-Progression Survival Influences Overall Survival among Patients with Advanced Non-Small Cell Lung Cancer Undergoing First-Line Pembrolizumab Monotherapy

BACKGROUND

Among patients with non-small cell lung cancer (NSCLC), the impact of first-line treatment on overall survival (OS) may be influenced by subsequent therapies. Thus, using patient-level data, we assessed the relationships of progression-free survival (PFS) and post-progression survival (PPS) with OS among patients with high-programmed death-ligand 1 (PD-L1) expression undergoing first-line pembrolizumab monotherapy for NSCLC.

METHODS

We reviewed data from 133 patients with high PD-L1 expression undergoing first-line pembrolizumab monotherapy for NSCLC at 6 Japanese centers between February 2017 and December 2018. The correlations of PFS and PPS with OS were evaluated at the patient level.

RESULTS

Linear regression analyses and Spearman's rank correlation coefficient revealed that PPS was strongly correlated with OS (r = 0.76, p < 0.05, R2 = 0.65), while PFS was only moderately correlated with OS (r = 0.71, p < 0.05, and R2 = 0.4). Furthermore, PPS was significantly associated with performance status at the end of pembrolizumab monotherapy, as well as the use of platinum-based combination chemotherapy after pembrolizumab monotherapy (both p < 0.05).

CONCLUSIONS

Among patients with high PD-L1 expression undergoing first-line pembrolizumab monotherapy for NSCLC, PPS was more strongly correlated with OS, relative to the relationship between PFS and OS. Therefore, subsequent treatment appears to significantly influence OS in patients with disease progression following first-line pembrolizumab monotherapy.

Surrogate Endpoints in Oncology: Overview of Systematic Reviews and Their Use for Health Decision Making in Mexico

OBJECTIVES

The use of surrogate endpoints (SEs) for cancer drug approval in health systems is common. The objectives of this study were to identify systematic reviews (SRs) that evaluated the correlation of SEs with overall survival (OS) in cancer drugs to analyze the applications of approved cancer drugs with SEs in Mexico and to apply the validation framework proposed by the Institute for Quality and Efficiency in Health Care (IQWiG).

METHODS

An overview of SRs was conducted according to Cochrane Collaboration methodology. Applications for approved cancer drugs with SEs in Mexico were analyzed. The IQWiG validation framework was applied to evaluate the SEs identified in the overview and in the applications in Mexico.

RESULTS

A total of 85 SRs that assessed 192 SEs for different types of cancer were selected. According to the IQWiG model, only 2.5% of the SEs analyzed in the overview and only one of the applications in Mexico could be used as surrogates for OS because the reliability (methodological quality) of the SRs and the strength of the correlation of SEs with OS was mostly low (92%) and low (correlation coefficient r ≤ 0.7; 50.5%), respectively. Of the total number of cancer drugs approved in Mexico, 19.4% used SEs.

CONCLUSIONS

Most SEs for different types of cancer could not be used as surrogates for OS according to the IQWiG model, and their use for the approval of cancer drugs in Mexico is generally not justified.

Skeletal Muscle Volume Is an Independent Predictor of Survival after Sorafenib Treatment Failure for Hepatocellular Carcinoma

Few studies exist on the relationship between post-progression survival (PPS) and skeletal muscle volume in hepatocellular carcinoma (HCC) patients receiving sorafenib. This study aimed to analyze the effects of muscle volume on clinical outcomes. We retrospectively enrolled 356 HCC patients. Various clinical parameters, including skeletal muscle index, were analyzed as predictors of overall survival (OS), progression-free survival (PFS), and PPS. Patients with high muscle volume showed longer survival or PPS than those with low muscle volume (median survival time: 12.8 vs. 9.5 months, p = 0.005; median PPS: 8.2 vs. 6.3 months, p = 0.015); however, no differences in PFS were found. Multivariate analysis indicated that muscle volume was an independent predictor of PPS and OS. Skeletal muscle volume was a PPS predictor in HCC patients receiving sorafenib. Therefore, survival can be prolonged by the upregulation of skeletal muscle volume, especially in HCC patients with skeletal muscle depletion.

Doubling the Dose of Bevacizumab Beyond Progression in Metastatic Colorectal Cancer-the Experience of a Tertiary Cancer Center

Background: Colorectal cancer (CRC) is the third most common cancer in Europe, with an annual increase in incidence ranging between 0.4 and 3.6% in various countries. Although the development of CRC was extensively studied, limited number of new therapies were developed in the last few years. Bevacizumab is frequently used as first- and second-line therapy for management of metastatic CRC (mCRC). The aim of this study is to present our experience with using bevacizumab beyond disease progression at different dosage levels in mCRC patients, in terms of overall survival, progression-free survival, time to treatment failure, and toxicities.

Methods: We performed a consecutive retrospective analysis of patients with confirmed mCRC who were treated with bevacizumab at "Prof Dr. Ion Chiricuta" Institute of Oncology, Cluj-Napoca, Romania. We included patients who had received bevacizumab as first- or second-line therapy and further stratified them according to the dose administered as a second-line (either standard dose of 5 mg/kg every 2 weeks or 7.5 mg/kg every 3 weeks, or double dose of 10 mg/kg every 2 weeks or 15 mg/kg every 3 weeks–depending on the classical chemotherapy partner). All patients had received bevacizumab beyond progression (BYP) which is defined as continuing bevacizumab administration through second-line treatment despite disease progression. In each group, we evaluated the prognostic factors that influenced survival and treatment outcome.

Results: One hundred and fifty-one (151) patients were included in the study. Themedian age of patients receiving double dose bevacizumab (DDB) and standard dose bevacizumab (SDB) was 58 years (range 41–71) and 57 years (range 19–75), respectively. The median overall survival in the DDB group was 41 months (range 27–49) compared to 25 months (range 23–29) in the SDB group (p = 0.01 log-rank test). First-line oxaliplatin-based treatment was used more frequently regardless of group, while irinotecan-based more frequently used as a second-line treatment (p = 0.014). Both oxaliplatin- and irinotecan-based regimens were found to be suitable partners for BYP. Statistical analysis revealed that dose intensity, primary tumor location, and cumulative exposure to BYP had significant influence on survival.

Conclusion: Doubling the dose of bevacizumab after first progression may improve survival in mCRC patients. Increasing bevacizumab dose intensity could override the prognostic impact of primary tumor location in patients receiving double the dose of bevacizumab after first disease progression.

Clinical impact of post-progression survival on overall survival in patients receiving nivolumab monotherapy as a second-line treatment for advanced non-small cell lung cancer

Background

The effect of second‐line treatment on overall survival (OS) may be affected by subsequent treatment in patients with non‐small cell lung cancer (NSCLC); however, in such patients, the correlation between post‐progression survival (PPS) and OS is unclear. Our study assessed the correlation of progression‐free survival (PFS) and PPS with OS, using individual patient data, in advanced NSCLC patients who were treated with second‐line nivolumab monotherapy,

Methods

Between January 2016 and March 2019, we evaluated 92 NSCLC patients who received second‐line nivolumab treatment after first‐line platinum‐based combination chemotherapy. Using individual patient data, the correlations of PFS and PPS with OS were examined.

Results

Linear regression and Spearman rank correlation analysis demonstrated that PPS was strongly correlated with OS (r = 0.85, p < 0.05, R² = 0.75), while PFS was moderately correlated with OS (r = 0.65, p < 0.05, R² = 0.42). Performance status at the beginning of second‐line treatment, immune checkpoint inhibitor rechallenge, and the number of treatment regimens used post‐progression, after the second‐line treatment significantly correlated with PPS (p < 0.05). In advanced NSCLC patients who underwent second‐line treatment with nivolumab, in comparison to PFS, there was a stronger correlation between PPS and OS.

Conclusions

Our findings suggest that subsequent treatment for disease progression after a second‐line nivolumab treatment had a significant impact on OS.

Are Quality of Randomized Clinical Trials and ESMO-Magnitude of Clinical Benefit Scale Two Sides of the Same Coin, to Grade Recommendations for Drug Approval?

The approval of a new drug for cancer treatment by the US Food and Drug Administration (FDA) and the European Medicines Agency (EMA) is based on positive, well-designed randomized phase III clinical trials (RCTs). However, not all of them are analyzed to support the recommendations. For this reason, there are different scales to quantify and evaluate the quality of RCTs and the magnitude of the clinical benefits of new drugs for treating solid tumors. In this review, we discuss the value of the progression-free survival (PFS) as an endpoint in RCTs and the concordance between it and the overall survival (OS) as a measure of the quality of clinical trial designs. We summarize and analyze the different scales to evaluate the clinical benefits of new drugs such as the The American Society of Clinical Oncology value framework (ASCO-VF-NHB16) and European Society for Medical Oncology Magnitude of Clinical Benefit Scale (ESMO-MCBS) and the concordance between them, focusing on metastatic colorectal cancer (mCRC). We propose several definitions that would help to evaluate the quality of RCT, the magnitude of clinical benefit and the appropriate approval of new drugs in oncology.

Treatment sequences of patients with advanced colorectal cancer and use of second-line FOLFIRI with antiangiogenic drugs in Japan: A retrospective observational study using an administrative database

The objectives were to describe treatment sequences for advanced colorectal cancer (CRC), use of second-line FOLFIRI (leucovorin, 5-fluorouracil, irinotecan) plus antiangiogenic drug (bevacizumab, ramucirumab, aflibercept beta) therapy, and the factors associated with the duration of antitumor drug treatment from second-line antiangiogenic therapy in Japan. This retrospective observational study was conducted using a Japanese hospital-based administrative database. Patients were enrolled if they started adjuvant therapy (and presumably experienced early recurrence) or first-line treatment for advanced CRC between May 2016 and July 2019, and were analysed until September 2019. Factors associated with overall treatment duration from second-line treatment with FOLFIRI plus antiangiogenic drugs were explored with multivariate Cox regression analysis. The most common first-line treatments were FOLFOX (leucovorin, 5-fluorouracil, oxaliplatin) or CAPOX (capecitabine, oxaliplatin) with bevacizumab (presumed RAS-mutant CRC) and FOLFOX with panitumumab (presumed RAS-wild type CRC). The most common second-line treatments were FOLFIRI-based. Many patients did not transition to subsequent lines of therapy. For second-line treatment, antiangiogenic drugs were prescribed more often for patients with presumed RAS-mutant CRC, right-sided CRC, and independent activities of daily living (ADL). The median duration of second-line FOLFIRI plus antiangiogenic drug treatment was 4.5 months; 66.2% of patients transitioned to third-line therapy. Low body mass index and not fully independent ADL were significantly associated with shorter overall duration of antitumor drug treatment from second-line therapy. Left-sided CRC, presumed RAS-wild type CRC, previous use of oral fluoropyrimidines and use of proteinuria qualitative tests, antihypertensives, or anticholinergics during second-line therapy were significantly associated with longer treatment. Treatment of advanced CRC in Japan is consistent with both international and Japanese guidelines, but transition rates to subsequent therapies need improvement. In addition to antitumor drug treatment, better ADL, higher body mass index, management of hypertension, and proteinuria tests were associated with continuation of sequential therapy that included antiangiogenic drugs.

Hypoxia‑induced circCCDC66 promotes the tumorigenesis of colorectal cancer via the miR‑3140/autophagy pathway

Circular RNAs (circRNAs) have been reported to be involved in the progression of colorectal cancer (CRC). However, the biological role of circCCDC66 in CRC remains unclear. Therefore, the present study aimed to elucidate the mechanisms through which circCCDC66 affects the hypoxia‑induced progression of CRC. It was found that hypoxia promoted the progression of CRC and upregulated the expression of circCCDC66. Furthermore, circCCDC66‑knockdown reduced viability, migration and invasion, and enhanced the apoptosis of hypoxia‑exposed CRC cells. Using the starBase database, it was identified that circCCDC66 may bind to miR‑3140. Subsequently, it was confirmed that circCCDC66 serves as a sponge of miR‑3140 and the depletion of miR‑3140 partly abolished the effects of circCCDC66 on the phenotype of hypoxia‑exposed CRC cells. In addition, miR‑3140 was validated to inhibit the autophagy pathway. The use of an autophagy inducer partially reversed the miR‑3140 overexpression‑induced inhibition of the viability and invasion, and the promotion of the apoptosis of hypoxia‑exposed CRC cells. In summary, the findings of the present study demonstrated that circCCDC66 facilitates the development of CRC cells under hypoxic conditions via regulation of miR‑3140/autophagy. These findings may provide a novel therapeutic option for patients with CRC.

Disagreement between patient- and physician-reported outcomes on symptomatic adverse events as poor prognosis in patients treated with first-line cetuximab plus chemotherapy for unresectable metastatic colorectal cancer: Results of Phase II QUACK trial

The status and prognostic value of the disagreement between physician and patient assessments of symptomatic adverse events (AEs) remain unclear for patients with metastatic colorectal cancer treated with first-line cetuximab plus chemotherapy. Paired data on patient-reported outcomes using the EORTC QLQ-C30 and physician-reported outcomes using the NCI-CTCAE for eight symptomatic AEs (fatigue, pain, insomnia, dyspnea, constipation, appetite loss, nausea/vomiting, and diarrhea) were collected from a prospective trial assessing the relationships between treatment efficacy, AEs, and quality of life. The overall agreement rates between patient and physician reporting at 4 weeks ranged from 40.2% to 76.5% for 129 patients. The level of agreement based on Cohen's κ statistics was slight to poor for dyspnea, pain, fatigue, and insomnia, while it was moderate to fair for the remaining AEs. No clinicopathological characteristics of disagreement were found. The underreporting by physicians ranged from 12.5% (nausea/vomiting) to 56.7% (fatigue). The 2-year overall survival (OS) rate was more favorable for patients with high agreement than for those with low agreement (71.2% vs. 46.5%, p = .016), and the agreement status was an independent factor of OS (HR, 2.31; 95% CI, 1.13-4.71; p = .022). For patients who were reported as asymptomatic by the physician, the presence of patient-reported symptoms resulted in a trend toward poor prognostic outcomes for appetite loss, dyspnea, diarrhea, and constipation. These findings provide the clinical importance of the monitoring of patient-reported symptoms that can be complementary to physician-reported data to ensure more accurate clinical outcomes.

Impact of subsequent chemotherapy on the survival of elderly patients with extensive stage small cell lung cancer

BACKGROUND/AIMS

The prognosis of small cell lung cancer (SCLC) is still poor because of rapid recurrence, despite good response to initial chemotherapy. Additionally, patients' old ages and comorbidities are often obstacles that make it difficult to apply subsequent treatment after initial treatment. This retrospective study analyzed the correlation of post-progression survival (PPS) with overall survival (OS), and prognostic factors including comorbidities to figure out impact of subsequent chemotherapy on OS in elderly extensive disease SCLC.

METHODS

We analyzed 101 patients of age 65 years or older who were recently diagnosed with extensive disease SCLC (ED-SCLC) in Korea University Medical Center between January 1995 and December 2015. The degree of comorbidity was scored using simplified comorbidity score (SCS). Correlation between PPS, progression-free survival (PFS) and OS was analyzed using a Pearson correlation coefficient. Cox proportional hazards regression was employed to examine the influence of clinical variables on survival.

RESULTS

Median age of patients was 71 years old (range, 65 to 83). Median OS was 8.7 months (range, 0.3 to 42.7). PPS was a reliable factor on OS than PFS (R2 = 0.852, p < 0.001). Prognostic factors associated with improved survival were SCS < 9, administration > 4 cycles of first line chemotherapy and subsequent second line chemotherapy.

CONCLUSION

PPS was more correlated with OS than PFS in elderly patients with ED-SCLC. The most important prognostic factors for PPS and OS included SCS and second line chemotherapy. Patients receiving subsequent treatment had increased OS regardless of degree of comorbidity.

Patient-reported symptom burden as a prognostic factor in treatment with first-line cetuximab plus chemotherapy for unresectable metastatic colorectal cancer: Results of Phase II QUACK trial

Background

It remains unclear whether patients’ self‐perceptions of symptoms at baseline clinically impact the prognostic relevance, treatment efficacy, or toxicity profiles in metastatic colorectal cancer (mCRC) patients treated with the first‐line cetuximab and standard chemotherapy.

Methods

The data were collected from a prospective trial that assessed the relationships between quality of life (QOL), treatment efficacy, and adverse events (AEs).

Results

The analysis of 137 mCRC patients revealed a significant association between the presence of baseline tumor‐related symptoms and a lower overall survival (OS) compared to the absence of symptoms (HR, 2.49; 95% CI, 1.37‐4.62; P = .003). The asymptomatic responders had favorable outcomes compared to the symptomatic nonresponders (2‐year OS rates: 83.6% and 35.9%, respectively), while the symptomatic responders had similar outcomes to the asymptomatic nonresponders. The median postprogression survival differed significantly: 10.2 months for the symptomatic patients and 15.9 months for the asymptomatic patients (HR, 2.29; 95% CI, 1.25‐4.29, P = .008). The objective response rates and patient toxicity profiles were similar irrespective of the severity of baseline symptoms.

Conclusion

Baseline symptoms were associated with worse OS but not with impaired treatment efficacy or more frequent AEs in mCRC patients treated with cetuximab in addition to chemotherapy.

Surrogacy of Time to Progression for Overall Survival in Advanced Hepatocellular Carcinoma Treated with Systemic Therapy: A Systematic Review and Meta-Analysis of Randomized Controlled Trials

Time to progression (TTP) is widely used as the endpoint in early-phase trials of advanced hepatocellular carcinoma (HCC). However, the relevance of using TTP as a surrogate marker for overall survival (OS) in pivotal trials remains uncertain. The PubMed database and ASCO Meeting Library were searched for reports of randomized controlled trials that investigated patients with advanced HCC, included data for both OS and TTP, and were launched between 2009 and 2016. The correlation between hazard ratios (HRs) for TTP and OS was determined using weighted linear regression. Correlations between median OS and TTP, and between median OS and postprogression survival (PPS), defined as the period obtained by subtracting the median TTP from the median OS, were also evaluated. The database search yielded 24 trials with 50 arms. Overall, TTP HR correlated with OS HR (R = 0.73); however, the coefficient in the regression equation was 0.48. The correlation between median OS and median TTP was not so strong (R = 0.50), whereas the correlation between median OS and median PPS was strong (R = 0.78). In advanced HCC, the OS HR can be predicted from the TTP HR, which is useful when considering whether to proceed to a pivotal trial based on the results of early-phase trials. TTP may be a better endpoint than OS for evaluating a novel agent in a pivotal trial, because an improvement in antitumor effect cannot fully reflect an improvement in OS due to the strong impact of PPS on OS.

CHALLENGES AND METHODOLOGIES IN USING PROGRESSION FREE SURVIVAL AS A SURROGATE FOR OVERALL SURVIVAL IN ONCOLOGY

OBJECTIVES

A primary outcome in oncology trials is overall survival (OS). However, to estimate OS accurately requires a sufficient number of patients to have died, which may take a long time. If an alternative end point is sufficiently highly correlated with OS, it can be used as a surrogate. Progression-free survival (PFS) is the surrogate most often used in oncology, but does not always satisfy the correlation conditions for surrogacy. We analyze the methodologies used when extrapolating from PFS to OS.

METHODS

Davis et al. previously reviewed the use of surrogate end points in oncology, using papers published between 2001 and 2011. We extend this, reviewing papers published between 2012 and 2016. We also examine the reporting of statistical methods to assess the strength of surrogacy.

RESULTS

The findings from 2012 to 2016 do not differ substantially from those of 2001 to 2011: the same factors are shown to affect the relationship between PFS and OS. The proportion of papers reporting individual patient data (IPD), strongly recommended for full assessment of surrogacy, remains low: 33 percent. A wide range of methods has been used to determine the appropriateness of surrogates. While usually adhering to reporting standards, the standard of scholarship appears sometimes to be questionable and the reporting of results often haphazard.

CONCLUSIONS

Standards of analysis and reporting PFS to OS surrogate studies should be improved by increasing the rigor of statistical reporting and by agreeing to a minimum set of reporting guidelines. Moreover, the use of IPD to assess surrogacy should increase.

The Nedd8-activating enzyme inhibitor MLN4924 suppresses colon cancer cell growth via triggering autophagy

Neddylation is a post-translational protein modification process. MLN4924 is a newly discovered pharmaceutical neddylation inhibitor that suppresses cancer growth with several cancer types. In our study, we first investigated the effect of MLN4924 on colon cancer cells (HCT116 and HT29). MLN4924 significantly inhibited the neddylation of cullin-1 and colon cancer cell growth in a time and dose-dependent manner. MLN4924 induced G2/M cell cycle arrest and apoptosis in HCT116 and HT29 cells. Moreover, MLN4924 also triggered autophagy in HCT116 and HT29 cells via suppressing the PI3K/AKT/mTOR pathway. Inhibiting autophagy by autophagy inhibitor 3-MA or ATG5 knockdown reversed the function of MLN4924 in suppressing colon cancer cell growth and cell death. Interestingly, MLN4924 suppresses colon cell growth in a xenograft model. Together, our finding revealed that blocking neddylation is an attractive colon cancer therapy strategy, and autophagy might act as a novel anti-cancer mechanism for the treatment of colon cancer by MLN4924.

Post-progression survival following second-line chemotherapy in patients with advanced pancreatic cancer previously treated with gemcitabine: a meta-analysis

Background Post-progression survival (PPS) could be a confounding element in interpreting data from clinical trials of second-line chemotherapy in patients with advanced pancreatic cancer (PC) previously treated with gemcitabine (GEM) because a recent meta-analysis of oxaliplatin combination therapy showed statistical heterogeneity for overall survival (OS) but not for progression-free survival (PFS). This study aimed to improve the understanding of the impact of PPS on OS in this setting. Methods Databases were searched to identify randomized controlled trials (RCTs) in the salvage setting. We evaluated relationships between OS and PFS, PPS, and other variables. Results Totally, 17 RCTs with 3253 patients were identified. Median OS was strongly and moderately associated with median PPS and PFS, respectively (r = 0.913; p < 0.001 and 0.780; p < 0.001, respectively). The proportion of patients with good performance status was significantly associated with both PPS and PFS (r = 0.574, p < 0.001 and 0.492, p < 0.001, respectively). The induction rate of subsequent chemotherapy was related to the duration of PPS and OS (r = 0.640, p < 0.001 and 0.647, p < 0.001, respectively). Median PPS and OS were significantly longer in recent trials than those in older trials (3.55 versus 2.78 months, p < 0.001 and 6.29 versus 5.02 months, p < 0.001). Conclusions Median PPS was strongly correlated with median OS. Given the recently increased opportunity for subsequent chemotherapy and supportive care, PPS may serve as an important element to clarify problems in this setting.

Overall survival and post-progression survival are potent endpoint in phase III trials of second/third-line chemotherapy for advanced or recurrent epithelial ovarian cancer

Purpose: A growing number of treatment options and active compounds in treatments have led to better outcomes for patients with advanced or recurrent epithelial ovarian cancer. We examined the association between progression-free survival (PFS), post-progression survival (PPS) and overall survival (OS) in phase III trials of second- and third-line chemotherapy for advanced or recurrent epithelial ovarian cancer. We aim to determine whether PFS or PPS is a surrogate of OS so that we can decide progress of disease is optimal endpoint for ovarian cancer.

Methods: We identified 22 trials conducted between January 1, 2000 through December 31, 2014 by literature search. We divided OS into PFS and PPS, and assessed the association between OS and PFS/PPS. We also examined whether the year of trial enrollment completion was associated with any variables.

Results: The median PPS was slightly longer in recent trials compared to older trials (10.0 vs. 8.8 months). While PPS was strongly associated with OS (r = 0.88) in all trials, PFS was moderately correlated with OS (r = 0.72). The correlation between OS and PPS in recent trials (r = 0.93) was stronger than in older trials (r = 0.84).

Conclusions: Our findings indicate that PPS is highly associated with OS in second/third-line chemotherapy for advanced or recurrent epithelial ovarian cancer, while the association between PFS and OS is moderate. We recommend using OS as primary endpoint for clinical trial of ovarian cancer, however PFS is still an optional endpoint.

Model-based meta-analysis of progression-free survival in non-Hodgkin lymphoma patients

BACKGROUND

Non-Hodgkin lymphoma (NHL) is a group of lymphoproliferative malignancies with varying treatment responses and progression-free survival (PFS) times. The objective of this study was to quantify the effect of treatment and patient-population characteristics on PFS in patients with NHL.

METHODS

A database was developed from 513 NHL clinical trials reported from 1993 to 2015. Summary-level PFS was obtained from 112 of these trials, which included 155 cohorts and 11,824 patients. Characteristics evaluated for their impact on PFS included cohort treatment, percentage of patients with each NHL subtype, percentage of patients with different numbers of prior treatments, percentage of subjects previously administered rituximab, performance status, disease stage, median age, and sex distribution.

RESULTS

Rituximab, bendamustine, CHOP (cyclophosphamide, doxorubicin, vincristine, and prednisone combination)/CHOP-like, and other nonchemotherapy drugs, aside from bortezomib, prolonged median PFS time 2 to 4-fold. Follicular lymphoma patients had 60% longer median PFS time than mantle cell lymphoma (MCL) patients, while diffuse large B-cell lymphoma patients had a median PFS time that was 25% of MCL patients. Patients who received ≤1 prior treatment had median PFS times > 10-fold longer than patients who received ≥2 prior treatments. The final model predicted the hazard ratio in 75% of the studies within 25% of the observed value and the observed median PFS time of 92% of the studies fell within the predicted 90% confidence intervals.

CONCLUSIONS

The developed PFS model predicts the median PFS time and hazard ratio for specific populations and treatment combinations quantitatively and can potentially be extended to link short-term and long-term clinical outcomes.

Surrogate Endpoints in Second-Line Trials of Targeted Agents in Metastatic Colorectal Cancer: A Literature-Based Systematic Review and Meta-Analysis

PURPOSE

The purpose of this study was to evaluate progression-free survival (PFS) and objective response rate (ORR) as surrogate endpoints of overall survival (OS) in modern clinical trials investigating the efficacy of targeted agents in the second-line treatment of metastatic colorectal cancer (mCRC).

MATERIALS AND METHODS

A systematic search of literature pertaining to randomized phase II and III trials evaluating targeted agents as second-line treatments for mCRC was performed. The strength of the correlation between both PFS and ORR and OS was assessed based on the Pearson's correlation coefficient (R) and the coefficient of determination (R2).

RESULTS

Twenty trials, including a total of 7,571 patients, met the search criteria. The median duration of post-progression survival (PPS) was 7.6 months. The median differences between experimental and control arms were 0.65 months (range, -2.4 to 3.4) for the median PFS and 0.7 months (range, -5.8 to 3.9) for the median OS. PFS and ORR showed moderate (R=0.734, R2=0.539, p < 0.001) and poor correlation (R=0.169, R2=0.029, p=0.476) with OS, respectively. No differences between anti-angiogenic agents and other drugs were evident.

CONCLUSION

Targeted agents investigated in the second-line treatment of mCRC provided minimal PFS gains translating into modest OS improvements. Considering both the moderate correlation between PFS and OS and the short duration of PPS, the OS should remain the preferred primary endpoint for randomized clinical trials in the second-line treatment of mCRC.

Clinical significance of post-progression survival in lung cancer

Progression-free survival (PFS) and overall survival (OS) are two common endpoints in cancer trials. OS is usually preferred, because it is reliable, precise, meaningful, and can easily be documented. However, subsequent lines of therapy might confound the effects of first-line treatment on OS. Whether PFS or OS is the more appropriate endpoint in clinical trials of metastatic cancer remains controversial. Previous reports on lung cancer have shown that an increase in PFS does not necessarily result in an increase in OS; however, post-progression survival (PPS) is strongly associated with OS after early-line treatment. The significance of PPS after first and second-line therapy at the individual level in patients with advanced lung cancer has also recently been reported. Findings of previous reports indicate that PPS is highly associated with OS after first and second-line chemotherapy in patients with advanced non-small cell lung cancer and small cell lung cancer, whereas PFS is only moderately associated with OS. Therefore, subsequent treatment after disease progression following early-line treatments may greatly influence OS. This review demonstrates that even in advanced lung cancer, PPS, rather than PFS, has become more strongly associated with OS over the years, potentially because of intensive post-study treatments. As a result of the increasing impact of PPS on OS, a PFS-related advantage does not necessarily indicate an OS-related advantage. Thus, the prolongation of PPS might limit the classical role of OS for assessing true efficacy derived from early-line chemotherapy in future clinical trials.

Update on optimal treatment for metastatic colorectal cancer from the ACTG/AGITG expert meeting: ECCO 2015

The treatment of metastatic CRC (mCRC) has evolved over the last 20 years, from fluoropyrimidines alone to combination chemotherapy and new biologic agents. Median overall survival is now over 24 months for RAS mutated (MT) patients and over 30 months for RAS wild-type (WT) patients. However, there are subgroups of patients with BRAF V600E MT CRC who have a significantly poorer outlook. Newer treatment options are also being explored in select subgroups of patients (anti-HER 2 in HER2 positive mCRC and immunotherapy in patients with defective mismatch repair (dMMR)). The best use of these systemic treatment options, as well as surgery in well-selected patients requires careful consideration of predictive biomarkers and importantly, the optimal sequence in which therapies should be given to derive maximal benefit. A group of colorectal subspecialty medical oncologists from Australia, USA, The Netherlands and Germany met during ECCO 2015 in Vienna to review current practice.

Post-Progression Survival Associated with Overall Survival in Patients with Advanced Non-Small-Cell Lung Cancer Receiving Docetaxel Monotherapy as Second-Line Chemotherapy

BACKGROUND

In patients with non-small-cell lung cancer (NSCLC), the effects of second-line chemotherapy on overall survival (OS) might be confounded by subsequent therapies. Therefore, using individual-level data, we aimed to determine the relationships between progression-free survival (PFS) and post-progression survival (PPS) with OS in patients with advanced NSCLC treated with docetaxel monotherapy as second-line chemotherapy.

METHODS

Between April 2002 and December 2014, data from 86 patients with advanced NSCLC who underwent second-line docetaxel monotherapy following first-line treatment with platinum combination chemotherapy were analyzed. The relationships of PFS and PPS with OS were analyzed at the individual level.

RESULTS

Spearman rank correlation and linear regression analyses showed that PPS was strongly associated with OS (r = 0.86, p < 0.05, R2 = 0.93), whereas PFS was moderately correlated with OS (r = 0.50, p < 0.05, R2 = 0.21). Performance status at the end of second-line treatment and the number of regimens after progression beyond second-line chemotherapy were significantly associated with PPS (p < 0.05).

CONCLUSIONS

In patients with advanced NSCLC with unknown oncogenic driver mutations undergoing docetaxel monotherapy as second-line chemotherapy, when compared with PFS, PPS had a stronger association with OS. This finding suggests that subsequent treatment after disease progression following second-line docetaxel monotherapy has a significant influence on OS.

Factors Associated with Length of Stay at Home in the Final Month of Life among Advanced Cancer Patients: A Retrospective Chart Review

BACKGROUND

Living at home is an important factor for maintaining high quality of life among patients. Many studies have discussed parameters associated with place of death, but no studies have yet clarified which factors influence the length of stay at home during the end of life.

OBJECTIVE

The aim of this study was to identify factors influencing the amount of time spent at home during the final month of life among patients with advanced cancer.

METHODS

A retrospective chart review was conducted for 415 patients with advanced cancer. Multivariate multiple linear regression analysis was used to examine relationships between the length of stay at home during the final month of life and variables measuring patient's background (four indicators), family structure (three indicators) cancer type (four types), chief complaint at initial palliative care referral (seven indicators), and medical interventions (three factors).

RESULTS

The multiple linear regression predicting time spent at home in the last month of life yielded partial regression coefficients of 4.2 for past outpatient palliative care services (OPCS) (p < 0.001) and 3.3 for in-home nurse visits (p = 0.003).

DISCUSSION

The most influential factor for length of stay at home in the final month of life was a history of OPCS. Many patients with advanced cancer who receive chemotherapy without OPCS spend time as inpatients after an initial period at home. Palliative care interventions for outpatients effectively enable patients with advanced cancer to adapt and continue living at home.

Positive relationship between subsequent chemotherapy and overall survival in pancreatic cancer: meta-analysis of postprogression survival for first-line chemotherapy

PURPOSE

To gain a better understanding of the impact of postprogression survival (PPS) and post-trial anticancer therapy on overall survival (OS) in first-line pancreatic cancer patients.

METHODS

A literature search identified 54 randomized trials, focusing on gemcitabine monotherapy to eliminate effects of heterogeneity of first-line regimens. We evaluated the relation between OS and either progression-free survival (PFS) or PPS. We also examined whether any association might be affected by the year of completion of trial enrollment.

RESULTS

For all 54 trials, PPS was strongly associated with OS (r = 0.844), whereas PFS was moderately associated with OS (r = 0.623). Average OS and PPS were significantly longer in recent trials than in older trials, (7.29 versus 6.15 months, p < 0.001) and (3.64 versus 2.86 months, p < 0.001), respectively. The correlation between OS and PPS in recent trials was much stronger than that in older trials (r = 0.846 versus 0.729). The relation between OS and PFS in recent and older trials did not differ (r = 0.595 versus 0.563). The percentage of patients with post-trial treatment was significantly higher in recent trials than in older trials (52.7 versus 39.7%, p < 0.001). The rate of post-trial anticancer therapy was significantly associated with OS (r = 0.910).

CONCLUSIONS

We found an increase in median PPS in accordance with an increase in median OS in recent trials compared with older trials and that rate of post-trial anticancer therapy was strongly associated with median OS. It is important that researchers be aware of these findings in designing clinical trials of first-line chemotherapy for pancreatic cancer patients.

Post-progression survival and progression-free survival in patients with advanced hepatocellular carcinoma treated by sorafenib

AIM

Although sorafenib is a standard drug for advanced hepatocellular carcinoma (HCC), little is known about a patient's clinical course after treatment. We investigated the effect of post-progression survival (PPS) and progression-free survival (PFS) on overall survival (OS) in patients whose advanced HCC was treated by sorafenib.

METHODS

We searched in the PubMed database for reports with survival data of patients with HCC treated with sorafenib monotherapy, and selected reports with 20 or more patients each that provided data for both OS and PFS or time to progression (TTP). Median PPS (mPPS) was defined as the period obtained by subtracting median PFS or TTP (mPFS/TTP) from median OS (mOS). We identified 56 reports with 5803 patients. We investigated the correlation of mOS and either mPPS or mPFS/TTP using weighted linear regression.

RESULTS

Median PPS correlated with mOS (r = 0.834) very strongly, whereas mPFS/TTP did not correlate with mOS as highly as PPS did (r = 0.546). When we stratified survival data by Child-Pugh classification, a significantly greater average percentage of mPPS to mOS was seen in Child-Pugh class A (54.4 ± 17.6%) than in Child-Pugh class B (32.0 ± 11.6%) (P = 0.015).

CONCLUSION

PPS highly correlated with OS, and its importance should be more emphasized for advanced HCC patients treated after sorafenib therapy, whereas we need to take more care in interpreting the results of PFS to evaluate treatment efficacy in clinical trials of advanced HCC.

Statistical controversies in clinical research: end points other than overall survival are vital for regulatory approval of anticancer agents

There is an ongoing debate about the relative merits of overall survival (OS) and other metrics that can be used as primary end points in cancer clinical trials. Although survival time is arguably the most objective metric for assessing the efficacy of anticancer treatment, OS as a clinical-trial end point needs to be conceptually distinguished from increased survival time as a goal desired by patients, clinicians and public-health policy makers. OS presents several drawbacks as a primary end point that threatens to hamper further drug development, including the increase in the number of patients and the much longer follow-up required in a clinical trial. In many settings of first-line therapy for metastatic disease, median OS is currently two to four times longer than median progression-free survival. As a result, the analysis of OS may be increasingly confounded by the effect of salvage therapies used after disease progression. In this review, we use straightforward statistical reasoning and examples from the oncology literature to argue that OS should no longer be the primary end point of most future phase III cancer clinical trials that aim at assessing the efficacy of novel therapies in the setting of metastatic disease.

Evaluation of sorafenib treatment and hepatic arterial infusion chemotherapy for advanced hepatocellular carcinoma: a comparative study using the propensity score matching method

While sorafenib (SFN) is the established worldwide standard therapeutic agent for advanced hepatocellular carcinoma (HCC), hepatic arterial infusion chemotherapy (HAIC) is also considered a favorable treatment for some advanced HCCs. This study aimed to evaluate each treatment and provide an optimal therapeutic choice for advanced HCCs. We analyzed 72 patients treated with SFN and 128 patients receiving HAIC. Both treatment groups were analyzed for prognostic and disease progression factors, and matched pair analysis was performed using the propensity score matching method. The preferable status of intrahepatic lesions, that is, no lesions or only a single (< 3 cm) intrahepetic lesion, was positively associated with good prognosis and negatively associated with disease progression in the SFN group. Maximum tumor size (> 5 cm) and low albumin (≤ 3.4 g/dL) were poor prognostic and disease progression factors in the HAIC group. Analysis of 53 patients selected from each of the SFN and HAIC groups based on the propensity score matching method showed no significant differences in survival or disease progression between the two matched subgroups. On the other hand, progression-free survival (PFS) in the HAIC-matched subgroup was significantly longer than in the SFN-matched subgroup, particularly in patients with portal vein invasion (PVI) and/or without extrahepatic spread (EHS). The treatment efficacy of HAIC is similar to that of SFN regarding survival and disease progression. Longer PFS might be expected for HAIC compared with SFN, particularly in patients with PVI and/or without EHS.

Why post-progression survival and post-relapse survival are not appropriate measures of efficacy in cancer randomized clinical trials

Comparisons of post-relapse survival (PRS) and post-progression survival have been used to measure efficacy in some cancer clinical trials. These comparisons are an attempt to account for second-line therapies and to identify benefits that do not translate in longer overall survival. However, the use of PRS comparisons can be misleading (either a longer or shorter PRS may indicate a benefit, depending on the circumstances) and can result in biased estimates (because of selection). Here, we describe the problems surrounding PRS comparisons and propose alternative approaches to deal with non-randomized therapies administered after progression to the experimental treatment.

Factors Associated with Post-Progression Survival in Patients with Advanced Hepatocellular Carcinoma Treated with Sorafenib

Sorafenib exerts modest antitumor activity in patients with advanced hepatocellular carcinoma (HCC), and radiological progressive disease (rPD) does not always correspond to so-called clinical progressive disease (cPD). We evaluated 101 patients who initiated sorafenib treatment for HCC and assessed post-progression survival (PPS) using the Cox proportional hazards model. PPS was calculated from the date of the first rPD until the date of death or the last follow-up. Using Cox model analysis of the 76 patients who experienced first rPD, we identified the Child-Pugh class, Eastern Cooperative Oncology Group performance status, the best antitumor response during treatment (using Response Evaluation Criteria in Solid Tumors (RECIST) Version 1.1) and α-fetoprotein levels as independent factors affecting PPS. When these factors were used to define scores ranging from zero to five with a cutoff value of two, PPS of patients who received best supportive care (BSC) after rPD was not statistically significantly different from that of patients who received post-rPD therapy with scores ≥2 (p = 0.220). In contrast, the PPS for the post-rPD therapy group was significantly longer compared with the BSC patients with scores <2 (p < 0.001). Patients who scored ≥2 at their first rPD were judged cPD and as candidates for BSC.

Guidelines for diagnosis, staging and treatment of metastatic colorectal cancer by Grupo Español Multidisciplinar en Cancer Digestivo (GEMCAD)

Abstract 

Advances in the care of patients with metastatic colorectal cancer arise from well-designed clinical trials. In the present document we address specific challenges in the design of clinical trials for metastatic colorectal cancer regarding staging and standard of care according to prognosis, as well as some relevant methodological issues.

Progression-free survival as surrogate endpoint in advanced pancreatic cancer: meta-analysis of 30 randomized first-line trials

BACKGROUND

Progression-free survival (PFS) has not been extensively investigated as a surrogate for survival in the first-line treatments of pancreatic cancer. The aim of this review was to evaluate PFS as a potential surrogate endpoint for overall survival (OS) in advanced pancreatic cancer in trials comparing poly-chemotherapy to gemcitabine alone.

DATA SOURCES

A systematic literature search in PubMed, Embase, Web of Science, and the Cochrane Central Register of Controlled Trials was conducted. The key words included randomized trial, first-line chemotherapy, pancreatic cancer, gemcitabine and poly-chemotherapy. Adjusted weighted linear regression was used to calculate RS (Spearman's rank-order correlation coefficient) between PFS and post-progression survival (PPS) with OS (RS) and between treatment effects on PFS and OS (RHR).

RESULTS

A total of 30 trials including 8467 patients met the inclusion criteria. Correlation between the treatment effects on PFS and OS (RHR=0.78) and between the endpoint PFS and OS was high across all studies (RS=0.75). The slope of the regression line was 0.76+/-0.26, indicating that an agent producing a 10% risk reduction for PFS will provide a 7.6%+/-2.6% risk reduction for OS. Correlation between PPS and OS was very strong (RS=0.71) and accounted for more than 50% of the whole OS variability (R2=0.57).

CONCLUSION

Because of the robust correlation with OS and the potential influence of PPS caused by the second line therapies, it may be justified to consider PFS as a surrogate endpoint in trials evaluating new cytotoxic agents when gemcitabine is the control arm.

Early tumour shrinkage as a prognostic factor and surrogate end-point in colorectal cancer: a systematic review and pooled-analysis

PURPOSE

Early tumour shrinkage (ETS), defined as a reduction of at least 20% in tumour size at first reassessment, has been recently investigated retrospectively in first-line trials of metastatic colorectal cancer (CRC), and appears to be associated with better outcomes. We have performed a systematic review and meta-analysis of published trials to evaluate the prognostic value of ETS in CRC in terms of overall survival (OS) and progression-free survival (PFS).

MATERIAL AND METHODS

An electronic search of the PubMed, SCOPUS, EMBASE, the Web of Science, and the Cochrane Central Register of Controlled Trial databases identified trials that compared outcomes of patients with or without ETS during first-line chemotherapy for metastatic CRC. The OS, reported as a hazard ratio (HR) with a 95% confidence interval (CI), was the primary outcome measure; the correlation coefficient (R) between ETS with median OS was also estimated.

RESULTS

Twenty-one trials from 10 publications were analysed. Overall, patients with ETS were associated with a better OS (HR, 0.58; 95% CI, 0.53 to 0.64; P<0.00001) and PFS (HR, 0.57; 95% CI, 0.47-0.69; P<0.00001) compared with patients who were early non-responders. However, ETS was poorly correlated with OS in terms of surrogacy (R=0.37; 95% CI - 0.31-0.78; P=0.28).

CONCLUSIONS

ETS is a good prognostic factor but an inappropriate surrogate for predicting outcome in CRC patients. These findings support ETS as prognostic tool in ascertaining earlier non-responders; however, its role as a surrogate end-point deserves further evaluation.

Progression-free survival, post-progression survival, and tumor response as surrogate markers for overall survival in patients with extensive small cell lung cancer

OBJECTIVES

The effects of first-line chemotherapy on overall survival (OS) might be confounded by subsequent therapies in patients with small cell lung cancer (SCLC). We examined whether progression-free survival (PFS), post-progression survival (PPS), and tumor response could be valid surrogate endpoints for OS after first-line chemotherapies for patients with extensive SCLC using individual-level data.

METHODS

Between September 2002 and November 2012, we analyzed 49 cases of patients with extensive SCLC who were treated with cisplatin and irinotecan as first-line chemotherapy. The relationships of PFS, PPS, and tumor response with OS were analyzed at the individual level.

RESULTS

Spearman rank correlation analysis and linear regression analysis showed that PPS was strongly correlated with OS (r = 0.97, p < 0.05, R(2)= 0.94), PFS was moderately correlated with OS (r = 0.58, p < 0.05, R(2)= 0.24), and tumor shrinkage was weakly correlated with OS (r = 0.37, p < 0.05, R(2)= 0.13). The best response to second-line treatment, and the number of regimens employed after progression beyond first-line chemotherapy were both significantly associated with PPS ( p ≤ 0.05).

CONCLUSION

PPS is a potential surrogate for OS in patients with extensive SCLC. Our findings also suggest that subsequent treatment after disease progression following first-line chemotherapy may greatly influence OS.

Meta-analysis for the association between overall survival and progression-free survival in gastrointestinal stromal tumor

PURPOSE

Gastrointestinal stromal tumor (GIST) is a relatively rare tumor that is treated with targeted therapies in advanced stages. Randomized clinical trials (RCT) often require long follow-up and large sample sizes to evaluate overall survival (OS), the gold-standard measure of treatment efficacy. However, changes in therapy following disease progression may complicate survival assessments. Establishing surrogate endpoints may facilitate the drug approval and availability of new efficacious treatments; however, no published studies have investigated this topic in unresectable and/or metastatic GIST.

EXPERIMENTAL DESIGN

A systematic literature review identified 14 RCTs and five observational studies of sufficient methodologic quality published between January 1995 and December 2013 (29 treatment arms; 2,189 patients). Weighted linear regression was used to evaluate the relation between median OS and median progression-free survival (PFS) for all arms combined and stratified by treatment line, treatment type, and quality score.

RESULTS

Median OS and PFS were positively related with a correlation of 0.91. The association was still moderate (correlation 0.72) after eliminating four influential data points. In stratified analyses, correlation of OS and PFS was greater in later lines of therapy (first line = 0.52; second line = 0.80; third- and later-line = 0.70) and imatinib showed a stronger association (0.91) than other evaluated treatments (-0.26 to 0.69).

CONCLUSION

This analysis identified a strong relationship between median OS and PFS, especially in later lines of therapy. Findings suggest that PFS could serve as a surrogate marker for OS; however, analyses of patient-level data are needed to establish its validity in GIST.

S-1 plus oxaliplatin versus capecitabine plus oxaliplatin for the first-line treatment of patients with metastatic colorectal cancer: updated results from a phase 3 trial

Background

We report updated progression-free survival (PFS) and overall survival (OS) data from a trial that compared capecitabine plus oxaliplatin (CapeOX) versus S-1 plus oxaliplatin (SOX) for the first-line treatment of metastatic colorectal cancer.

Methods

This trial was a randomized, two-armed, non-inferiority phase 3 comparison of CapeOX (capecitabine 1000 mg/m2 twice daily on days 1–14 and oxaliplatin 130 mg/m2 on day 1) versus SOX (S-1 40 mg/m2 twice daily on days 1–14 and oxaliplatin 130 mg/m2 on day 1). The primary end point was to show non-inferiority of SOX relative to CapeOX in terms of PFS. Thus, a follow-up exploratory analysis of PFS and OS was performed.

Results

The intention to treat (ITT) population was comprised of 340 patients (SOX arm: 168 and CapeOX arm: 172). The updated median PFS was 7.1 months (95% CI 6.4-8.0) in the SOX group and 6.3 months (95% CI 4.9-6.7) in the CapeOX group (hazard ratio [HR], 0.83 [0.66-1.04], p = .10). The median OS was 19.0 months (95% CI 15.3-23.0) in the SOX group and 18.4 months (95% CI 14.1-20.7) in the CapeOX group (HR, 0.86 [0.68-1.08], p = .19). Subgroup analyses according to principal demographic factors such as sex, age, ECOG (Eastern Cooperative Oncology Group) performance status, primary tumor location, measurability, previous adjuvant therapy, number of metastatic organs, and liver metastases showed no interaction between any of these characteristics and the treatment.

Conclusions

Updated survival analysis shows that SOX is similar to CapeOX, confirming the initial PFS analysis. Therefore, the SOX regimen could be an alternative first-line doublet chemotherapy strategy for patients with metastatic colorectal cancer.

Trial registration

NCT00677443 and May 12 2008

Therapeutic evaluation criteria for advanced colorectal cancer: Recent progress

Evaluation criteria like overall survival (OS), progression-free survival (PFS), the response evaluation criteria in solid tumors, quality of life and adverse reactions have been widely used in clinical studies of advanced colorectal cancer. However, these criteria have different significance, and with the development of molecular targeted drugs and new therapies, the drawbacks of these criteria have been revealed. Therefore, searching for new evaluation criteria which can reflect the curative effect in the earlier stage is becoming inevitable.

Which strategy after first-line therapy in advanced colorectal cancer?

Second-line therapy for advanced colorectal cancer is an integral part of the treatment strategy that needs to be set from the beginning for each patient, bearing in mind the expected toxicities of chosen treatments, the patient's clinical condition, comorbidities, preferences, the aims of the treatment and the molecular status. Furthermore, the distinction between lines of therapy is no longer absolute. The perspective of “continuum of care” includes switching chemotherapy prior to disease progression, maintenance therapy, drug "holidays" if needed, surgical resection of metastases in selected patients, and seems to allow a tailored treatment, in which patients are more likely to benefit from exposure to all active agents, which is known to correlate with overall survival. The scenario of second-line treatment has changed dramatically over the years and could currently benefit from several options including chemotherapy with a single agent or in combination and the addition of molecular-targeted agents developed in the last decade, such as epidermal growth factor receptor antibodies (cetuximab, panitumumab) and vascular endothelial growth factor-targeting agents (bevacizumab, aflibercept), with the possibility of bevacizumab use even beyond first progression. The purpose of this review is to summarize the most important scientific data supporting the use of chemotherapy and the new biologic agents in the second-line setting in advanced colorectal cancer.

Surrogate endpoints for overall survival in advanced non-small-cell lung cancer patients with mutations of the epidermal growth factor receptor gene

Subsequent therapies confound the ability to discern the effect of first-line chemotherapy on overall survival (OS). We investigated whether progression-free survival (PFS), post-progression survival (PPS) and tumor response were valid surrogate endpoints for OS following first-line chemotherapy in individual patients with advanced non-small-cell lung cancer (NSCLC) harboring sensitive epidermal growth factor receptor gene mutations. We retrospectively analyzed 35 patients with advanced NSCLC treated with first-line gefitinib. The associations of PFS, PPS and tumor response with OS were analyzed. PPS was found to be strongly correlated with OS, unlike PFS and tumor shrinkage. The factors significantly associated with PPS were performance status (PS) after first-line treatment, best response to second-line treatment and number of regimens used after disease progression. PPS may be a surrogate for OS in this patient population and further therapy after disease progression following first-line chemotherapy may significantly affect OS. However, a larger study is required to validate these results.