Hazard Ratios For Event-free Survival Research Articles

Abstract 3638: Pathologic endpoints as surrogates for survival endpoints in neoadjuvant immunotherapy clinical trials for non-small cell lung cancer

Abstract Background: The use of neoadjuvant immunotherapy alone or in combination has rapidly evolved in the last 5 years. There is significant debate as to whether pathologic complete response (pCR) or major pathologic response (MPR) can be considered a surrogate endpoint for survival. We therefore performed a systematic review and meta-analysis to evaluate the surrogacy of pCR and MPR for event free survival (EFS) in neoadjuvant clinical trials for early-stage NSCLC. Methods: We performed a systematic literature search on PubMed and reviewed abstracts of the most relevant international conferences until June 2023. Relevant information relative to response rates, Odds Ratios (ORs) of response, 2-years EFS rates and Hazard ratios (HRs) were retrieved from all eligible clinical trials and the association were analyzed. To evaluate patients level surrogacy the association between response rate and 2-year EFS was evaluated. In trials presenting EFS rates by achievement of pCR and MPR a forest plot with random effect model was also produced. For trial level surrogacy, ORs for pCR and MPR and HRs for EFS were retrieved and analyzed using a linear regression model weighted by sample size. R2 and linear regression slope were used respectively to estimate the proportion of variation in EFS effect explained by pCR effect and the magnitude of change in EFS effect as a function of the magnitude of change in pCR effect. The R2 with 95% CI were calculated by bootstrapping approach. Results: Seven RCTs were identified for a total of 2940 patients. At patient level, the R2 of pCR and MPR with 2-years EFS were 0.82 (0.66-0.94) and 0.81 (0.63-0.93), respectively, with slopes of 0.96 (0.68-1.19) and 0.64 (0.45-0.85), respectively. At trial level, R2 for association of OR for response and HR for EFS was 0.58 (0.00-0.97) and 0.61 (0.00-0.97) for pCR and MPR, respectively. Conclusions: While we were able to show a strong correlation between pCR and EFS, trial level surrogacy was not proven. The lack of surrogacy can be related to the high heterogeneity among clinical trials and the still scarce number of data available. More research to reduce the heterogeneity (e.g., pathological evaluation, surgery, and staging harmonization) must be done to introduce pCR as a primary measure to predict EFS. Citation Format: Robert B. Cameron, Jacobi B. Hines, Alessandra Esposito, Christine Bestvina, Marina C. Garassino, Valter Torri, Rajat Thawani. Pathologic endpoints as surrogates for survival endpoints in neoadjuvant immunotherapy clinical trials for non-small cell lung cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 3638.

Surrogate endpoints for overall survival in randomised controlled trials of localised osteosarcoma: A meta-analytic evaluation

Event-free survival (EFS) is considered the most reliable surrogate endpoint for overall survival (OS) in randomised controlled trials (RCTs) of adjuvant therapies for malignant tumours. However, the surrogacy of intermediate endpoints such as EFS for OS in trials of patients with osteosarcoma has not been investigated to date. In this study, we investigated the correlation between OS and intermediate endpoints in RCTs of localised osteosarcoma. A systematic search identified 20 relevant RCTs. The correlations between the surrogate endpoints and OS were evaluated using weighted linear regression analyses and by calculating the Spearman rank correlation coefficients (ρ). The strength of the correlation was determined by calculating the coefficient of determination (R2). A total of 5,620 patients were randomly assigned to 45 treatment arms in the eligible 20 RCTs. The correlation between the hazard ratios for EFS and OS was moderate (R2 = 0.456, ρ = 0.440); this correlation tended to be weaker for patients with localised osteosarcoma excluding the patients with metastases. Overall, the trial-level correlation between the surrogate endpoints and OS was not robust in RCTs of osteosarcoma published to date. Hence, the suitability of the intermediate endpoints as surrogates for OS could not be confirmed.

A meta-analytic evaluation of the correlation between event-free survival and overall survival in randomized controlled trials of newly diagnosed Ewing sarcoma

BackgroundIn randomized controlled trials (RCTs) of adjuvant treatment for malignant tumors, event-free survival (EFS) is considered the most acceptable surrogate for overall survival (OS). However, even though EFS has repeatedly been selected as a primary endpoint in RCTs of Ewing sarcoma (ES), the surrogacy of EFS for OS has not been investigated. This study aimed to evaluate the correlation between EFS and OS in RCTs of chemotherapy for newly diagnosed ES using a meta-analytic approach.MethodsWe identified seven RCTs of newly diagnosed ES through a systematic review, and a meta-analysis was performed to evaluate the efficacy and adverse events associated with chemotherapy for previously untreated ES. The correlation between EFS and OS was investigated using weighted linear regression analysis and Spearman rank correlation coefficients (ρ). The strength of the correlation was evaluated using the coefficient of determination (R2).ResultsA total of 3612 patients were randomly assigned to 17 treatment arms in the eligible RCTs. The meta-analysis revealed that the hazard ratios for OS and EFS showed significantly better results in the experimental treatment groups with increasing toxicities. The correlation between the hazard ratios for EFS and OS was good (R2 = 0.747, ρ = 0.683), and the correlation tended to be more favorable in cases of localized ES (R2 = 0.818, ρ = 0.929).ConclusionsOverall, the trial-level correlation between EFS and OS was good for newly diagnosed ES and was very good in cases of localized disease. EFS may be a useful endpoint in RCTs of ES chemotherapy, and it is worth verifying using individual patient data.

Predictors of clinical outcome in pediatric oligodendroglioma: meta-analysis of individual patient data and multiple imputation.

OBJECTIVE Oligodendroglioma is a rare primary CNS neoplasm in the pediatric population, and only a limited number of studies in the literature have characterized this entity. Existing studies are limited by small sample sizes and discrepant interstudy findings in identified prognostic factors. In the present study, the authors aimed to increase the statistical power in evaluating for potential prognostic factors of pediatric oligodendrogliomas and sought to reconcile the discrepant findings present among existing studies by performing an individual-patient-data (IPD) meta-analysis and using multiple imputation to address data not directly available from existing studies. METHODS A systematic search was performed, and all studies found to be related to pediatric oligodendrogliomas and associated outcomes were screened for inclusion. Each study was searched for specific demographic and clinical characteristics of each patient and the duration of event-free survival (EFS) and overall survival (OS). Given that certain demographic and clinical information of each patient was not available within all studies, a multivariable imputation via chained equations model was used to impute missing data after the mechanism of missing data was determined. The primary end points of interest were hazard ratios for EFS and OS, as calculated by the Cox proportional-hazards model. Both univariate and multivariate analyses were performed. The multivariate model was adjusted for age, sex, tumor grade, mixed pathologies, extent of resection, chemotherapy, radiation therapy, tumor location, and initial presentation. A p value of less than 0.05 was considered statistically significant. RESULTS A systematic search identified 24 studies with both time-to-event and IPD characteristics available, and a total of 237 individual cases were available for analysis. A median of 19.4% of the values among clinical, demographic, and outcome variables in the compiled 237 cases were missing. Multivariate Cox regression analysis revealed subtotal resection (p = 0.007 [EFS] and 0.043 [OS]), initial presentation of headache (p = 0.006 [EFS] and 0.004 [OS]), mixed pathologies (p = 0.005 [EFS] and 0.049 [OS]), and location of the tumor in the parietal lobe (p = 0.044 [EFS] and 0.030 [OS]) to be significant predictors of tumor progression or recurrence and death. CONCLUSIONS The use of IPD meta-analysis provides a valuable means for increasing statistical power in investigations of disease entities with a very low incidence. Missing data are common in research, and multiple imputation is a flexible and valid approach for addressing this issue, when it is used conscientiously. Undergoing subtotal resection, having a parietal tumor, having tumors with mixed pathologies, and suffering headaches at the time of diagnosis portended a poorer prognosis in pediatric patients with oligodendroglioma.

Favorable prognosis of biallelic CEBPA gene mutations in acute myeloid leukemia patients: a meta-analysis.

Increasing number of studies suggested that biallelic CEBPA (bi CEBPA) mutations were associated with favorable prognosis in patients with acute myeloid leukemia (AML), but the results remain inconclusive. We therefore present a meta-analysis to evaluate the prognostic value of bi CEBPA mutations in patients with AML. A comprehensive literature search was undertaken through August 2014 looking for eligible studies. Pooled hazard ratios (HRs) estimates and 95% confidence intervals (95% CIs) in overall survival (OS) and event-free survival (EFS) were used to calculate estimated effect. Ten studies covering a total of 6219 subjects were included in this analysis. Overall, bi CEBPA mutations were associated with favorable clinical outcome in patients with AML (HR for EFS: 0.41, 95% CI: 0.32-0.52; for OS: 0.37, 95% CI: 0.27-0.50), in cytogenetically normal (CN)-AML (HR for EFS: 0.38, 95% CI: 0.29-0.49; for OS: 0.32, 95% CI: 0.23-0.43). When took the cohort of monoallelic CEBPA (mo CEBPA) mutated and wild-type CEBPA (wt CEBPA) AML as a reference group, bi CEBPA mutated AML also shown beneficial outcomes (HR for OS: 0.52, 95% CI: 0.37-0.72). No significant difference was found between mo CEBPA mutation and wt CEBPA in patients with AML or CN-AML (P > 0.05). Bi CEBPA mutations in patients with AML are strongly associated with a favorable prognosis, which suggested that bi CEBPA mutations would potentially serve as a novel prognostic marker in AML.

Prognostic effect of blood transfusion in children with acute lymphoblastic leukemia

BackgroundMost children with acute lymphoblastic leukemia (ALL) receive blood transfusions. Transfusions may affect ALL outcomes through transfusion-related immunomodulation (TRIM).MethodsWe analyzed overall survival (OS) and event-free survival (EFS) in relation to leukocyte reduced and irradiated (LR/IRR) blood products transfused during the induction phase in 136 children with ALL. Hazard ratios (HRs) for death and relapse were estimated through Cox regression analysis.ResultsOne hundred and twenty patients (89%) were transfused with packed red blood cells (PRBCs) and 79 (58%) with single donor platelets (SDPs). The median number of transfusions was 2 (interquartile range [IQR]=1-3 events) and 1 (IQR=0-3 events) for PRBCs and SDPs, respectively. Patients who had white blood cell (WBC) count >50,000×109/L, were classified as high risk according to the high National Cancer Institute criteria, displayed a T cell phenotype, or were minimal residual disease-positive at end of induction were more likely to receive >3 transfusions during induction (P=0.001, 0.002, 0.03, and 0.01, respectively). In univariate analysis, PRBC, SDP, and fresh frozen plasma transfusions did not have any significant association with relapse or death. For PRBC transfusions, the HRs for EFS and OS were 1.02 (95% CI, 0.85-1.24; P=0. 76) and 1.03 (95% CI, 0.83-1.27; P=0.76), respectively. For SDP transfusions, HRs were 1.03 (95% CI, 0.90-1.18; P=0.64) and 0.98 (95% CI, 0.80-1.20; P=0.87) for EFS and OS, respectively.ConclusionLR/IRR blood products may not confer a TRIM effect in childhood ALL and are unlikely to affect outcome.

Predictive V16alue of Thymidylate Synthase Expression in Gastric Cancer: A Systematic Review with Meta-analysis

The relationship between thymidylate synthase (TS) expression and outcomes in gastric cancer (GC) patients remains controversial, although most studies reported poor survival and reduced response to fluoropyrimidine were related to high TS in tumors. We carried out a systematic review of the literature with meta-analysis to estimate the predictive value of TS expression from published studies. We identified 24 studies analysing the outcome data in gastric cancer stratified by TS expression. Effect measures of outcome were hazard ratios (HRs) for overall survival (OS) and event-free survival (EFS), or the odds ratio (OR) for overall response rate (ORR). HRs and ORs from these eligible studies were pooled using random-effects meta- analysis. Fifteen studies investigated outcomes in a total of 844 patients with advanced GC, and nine studies investigated outcomes in a total of 1,235 patients with localized GC undergoing adjuvant therapy. Meta- analysis of estimates showed high TS expression was significantly associated with poor OS in the advanced setting (HR: 1.43, 95%CI: 1.08 - 1.90), and poor EFS in the adjuvant setting (HR: 1.53, 95%CI: 1.01 - 2.32). Subgroup analysis demonstrated TS expression to have even greater value in predicting OS, EFS and ORR in advanced GC patients treated with fluoropyrimidine monotherapy (HR for OS: 2.32, 95%CI: 1.53 - 3.50; HR for EFS: 1.76, 95%CI: 1.19 - 2.60; OR for ORR: 0.32, 95%CI: 0.11 - 0.95). High levels of TS expression were associated with a poorer OS for advanced GC patients compared with low levels. In the adjuvant setting, high TS expression was also associated with a worse EFS. Additional studies with consistent methodology are needed to define the precise predictive value of TS.

HER2 and TOP2A as predictive markers for anthracycline-containing chemotherapy regimens as adjuvant treatment of breast cancer: a meta-analysis of individual patient data

Prediction of response to anthracycline-based therapy for breast cancer is challenging. We aimed to assess the value of HER2 and TOP2A as predictive markers of response to anthracycline-based adjuvant therapy in patients with early breast cancer. We did a meta-analysis of individual patient data from five randomised adjuvant trials that compared anthracycline-based regimens with cyclophosphamide, methotrexate, and fluorouracil (CMF) regimens. We assessed the status of HER2 and TOP2A genes with fluorescent in-situ hybridisation. Tumour samples were submitted to an external laboratory for validation. We calculated hazard ratios (HR) to compare event-free survival (EFS) and overall survival in patients receiving anthracycline-based treatment with those receiving CMF in two HER2 cohorts (HER2 amplified and non-amplified tumours) and in three TOP2A cohorts (normal, amplified, and deleted tumours). We analysed data for 3452 patients for HER2 and 3102 patients for TOP2A. For EFS, HRs were 0·89 (95% CI 0·79-1·01) for HER2 non-amplified patients and 0·71 (0·58-0·86) for HER2-amplified patients (p(interaction)=0·0485); for overall survival, HRs were 0·91 (95% CI 0·79-1·05) for HER2 non-amplified patients and 0·73 (0·59-0·89) for HER2-amplified patients (p(interaction)=0·0718). In analysis of TOP2A status, HRs for EFS were 0·88 (0·78-1·00) for normal, 0·63 (0·46-0·87) for deleted, and 0·62 (0·43-0·90) for amplified (p(interaction)=0·0513); HRs for overall survival were 0·89 (0·78-1·03) for normal, 0·68 (0·49-0·95) for deleted, and 0·67 (0·46-0·98) for amplified (p(interaction)=0·1608). When patients with TOP2A-deleted and TOP2A-amplified tumours were grouped together (altered cohort) and compared with data from patients with normal TOP2A tumours, HRs for EFS were 0·64 (0·50-0·81) for altered and 0·88 (0·78-1·00) for normal (p(interaction)=0·0183); HRs for overall survival were 0·67 (0·52-0·86) for altered and 0·89 (0·78-1·03) for normal (p(interaction)=0·0455). Although HER2 amplification and combined TOP2A amplification and deletion may have some value in the prediction of responsiveness to anthracycline-based chemotherapy, our findings do not support the use of anthracyclines only in patients with HER2-amplified or TOP2A-aberrated tumours. Associazione Italiana Ricerca Cancro, Academy of Finland, Belgian Federation Against Cancer, Cancer Research UK, Les Amis de l'Institut Bordet, Scottish Breast Cancer Trials Group, NCIC Clinical Trials Group, Canadian Cancer Society Research Institute, Danish Council for Strategic Research, Pharmacia-Upjohn (now Pfizer), and Abbott Laboratories.

O-96 Accelerated E-CMF (accE-CMF) chemotherapy with pegfilgrastim support in early stage breast cancer is associated with low incidence of severe lymphopenia

Prediction of response to anthracycline-based therapy for breast cancer is challenging. We aimed to assess the value of HER2 and TOP2A as predictive markers of response to anthracycline-based adjuvant therapy in patients with early breast cancer.We did a meta-analysis of individual patient data from five randomised adjuvant trials that compared anthracycline-based regimens with cyclophosphamide, methotrexate, and fluorouracil (CMF) regimens. We assessed the status of HER2 and TOP2A genes with fluorescent in-situ hybridisation. Tumour samples were submitted to an external laboratory for validation. We calculated hazard ratios (HR) to compare event-free survival (EFS) and overall survival in patients receiving anthracycline-based treatment with those receiving CMF in two HER2 cohorts (HER2 amplified and non-amplified tumours) and in three TOP2A cohorts (normal, amplified, and deleted tumours).We analysed data for 3452 patients for HER2 and 3102 patients for TOP2A. For EFS, HRs were 0·89 (95% CI 0·79–1·01) for HER2 non-amplified patients and 0·71 (0·58–0·86) for HER2-amplified patients (pinteraction=0·0485); for overall survival, HRs were 0·91 (95% CI 0·79–1·05) for HER2 non-amplified patients and 0·73 (0·59–0·89) for HER2-amplified patients (pinteraction=0·0718). In analysis of TOP2A status, HRs for EFS were 0·88 (0·78–1·00) for normal, 0·63 (0·46–0·87) for deleted, and 0·62 (0·43–0·90) for amplified (pinteraction=0·0513); HRs for overall survival were 0·89 (0·78–1·03) for normal, 0·68 (0·49–0·95) for deleted, and 0·67 (0·46–0·98) for amplified (pinteraction=0·1608). When patients with TOP2A-deleted and TOP2A-amplified tumours were grouped together (altered cohort) and compared with data from patients with normal TOP2A tumours, HRs for EFS were 0·64 (0·50–0·81) for altered and 0·88 (0·78–1·00) for normal (pinteraction=0·0183); HRs for overall survival were 0·67 (0·52–0·86) for altered and 0·89 (0·78–1·03) for normal (pinteraction=0·0455).Although HER2 amplification and combined TOP2A amplification and deletion may have some value in the prediction of responsiveness to anthracycline-based chemotherapy, our findings do not support the use of anthracyclines only in patients with HER2-amplified or TOP2A-aberrated tumours.Associazione Italiana Ricerca Cancro, Academy of Finland, Belgian Federation Against Cancer, Cancer Research UK, Les Amis de l'Institut Bordet, Scottish Breast Cancer Trials Group, NCIC Clinical Trials Group, Canadian Cancer Society Research Institute, Danish Council for Strategic Research, Pharmacia-Upjohn (now Pfizer), and Abbott Laboratories.