X Hu

Subgroup Analyses in Reporting of Phase III Clinical Trials in Solid Tumors

PURPOSE Treatment decisions in clinical oncology are guided by results from phase III randomized clinical trials (RCTs). The results of subgroup analyses may be potentially important in individualizing patient care. We investigated the appropriateness of the use and interpretation of subgroup analyses in oncology RCTs on the basis of the CONSORT statement requirements. METHODS Phase III RCTs published between January 1, 2011, and December 31, 2013, were reviewed to identify eligible studies of solid tumor treatments. Information related to the subgroup analyses included prespecification, number, subgroup factors, interaction test use, and claim of subgroup difference. RESULTS A total of 221 publications reporting data on 184,500 patients were analyzed. One hundred eighty-eight (85%) RCTs were reported with subgroup analyses. Of those, 146 (78%) trials were reported with at least six subgroups. For the majority of trials with subgroup analyses (173; 92%), the actual number of subgroup analyses conducted cannot be determined. Only 59 (31%) RCTs were reported with fully prespecified subgroups and only 64 (34%) trials were reported with interaction tests. In addition, 102 (54%) RCTs were reported with claims of subgroup differences. Of those, only 18 claims of RCTs (18%) were based on significant interaction test results. CONCLUSION The reporting of subgroup analyses in contemporary oncology RCTs is neither uniform nor complete; it requires improvement to ensure consistency and to provide critical information for guiding patient care. Major problems include testing of a large number of subgroups, subgroups without prespecifications, and inadequate use of interaction tests.

Biomarker assessment of the CBCSG006 trial: A randomized phase III trial of cisplatin plus gemcitabine compared with paclitaxel plus gemcitabine as first-line therapy for patients with metastatic triple-negative breast cancer.

Background CBCSG006 trial reported the superior efficacy of cisplatin plus gemcitabine (GP) regimen than paclitaxel plus gemcitabine (GT) regimen as first-line treatment of metastatic triple-negative breast cancer (mTNBC). This study focused on the updated survival data and the explorations of potential biomarkers for efficacy. Patients and methods Germ-line mutations of homologous recombination (HR) panel, BRCA1/2 included, were evaluated in 55.9% (132/236) patients. PD-L1 expression was evaluated in 48.3% (114/236) patients. A nonparametric sliding-window subpopulation treatment effect pattern plot (STEPP) methodology was used to analyze the absolute survival benefits. All statistical tests were two-sided. Results Median progression-free survival (PFS) was 7.73 [95% confidence interval (CI) 6.46-9.00] months for GP arm and 6.07 (95% CI 5.32-6.83) months for GT arm (P = 0.005). No significant difference in overall survival (OS) was observed. There was significant interaction between HR status and treatment for PFS and status of HR deficient significantly correlated with higher objective response rate (ORR) and longer PFS in GP arm than in GT arm (71.9% versus 38.7%, P = 0.008; 10.37 versus 4.30 months, P = 0.011). There was no significant interaction between germ-line BRCA1/2 (gBRCA1/2) status and treatment for PFS. Patients with gBRCA1/2 mutation had numerically higher ORR and prolonged PFS in GP arm than in GT arm (83.3% versus 37.5%, P = 0.086; 8.90 versus 3.20 months, P = 0.459). There was no significant interaction between PD-L1 status and treatment for PFS, and no significant differences in ORR, PFS or OS between two arms regardless of PD-L1 status. In STEPP analysis, patients with lower composite risks had more absolute benefits in PFS than those with higher composite risks. Conclusions GP regimen has superior efficacy than GT regimen as first-line chemotherapy for mTNBC patients. Germ-line mutations of BRCA1/2 and HR panel are possible biomarkers for better performance of cisplatin-based regimens. A composite risk model was developed to guide patient selection for GP treatment in TNBC patients. Trial registration ClinicalTrials.gov, NCT01287624.

Comparison of primary endpoints between publications, registries, and protocols of phase III cancer clinical trials

Background Decisions by leading journals to require trial registration and to make protocols of phase III randomized clinical trials (RCTs) publicly accessible were landmark events in clinical trial reporting. Materials and Methods We identified phase III cancer RCTs published between 2013 and 2015 in New England Journal of Medicine (NEJM), The Lancet, The lancet Oncology, JAMA and Journal of Clinical Oncology (JCO). Results We identified 345 reports of phase III RCTs of which 217 (62.9%) had available protocols. The availability rates for NEJM, The Lancet, The Lancet Oncology, JAMA and JCO were 98.0%, 33.3%, 22.7%, 55.6% and 88.3%, respectively. Journal and publication year were significantly associated with protocol availability. Eight of 215 trials (3.7%) with English language protocols had a discrepancy in primary endpoints between publication and protocol. Discrepancies of primary endpoints between protocol and registration existed in 16 (7.7%) of 209 trials. Conclusions The policy of providing protocols with articles reporting RCTs has not been enforced rigorously. Selective reporting of primary endpoints only remains in a small fraction of phase III trials. Further improvement in consistency between primary endpoints registered and that in protocol is necessary.

Abstract P6-09-29: Clinicopathological characteristics and survival outcomes in invasive papillary carcinoma of the breast: A population-based study

Background Invasive papillary carcinoma (IPC) is defined as having papillary architecture in >90% of the invasive component. The overall incidence of IPC is low, accounting for less than 1-2% of all newly diagnosed cases of invasive breast cancer. Limited data are available that contribute to a comprehensive summarization of the clinicopathological characteristics and prognostic factors that are associated with IPC. We aimed to determine the clinicopathological characteristics and prognostic factors of IPC in a large population and help physicians to acquire a better understanding of the disease and make better informed therapeutic decisions. Methods We identified 233,171 female patients in the Surveillance, Epidemiology, and End Results (SEER) database who had IPC (n = 524) or infiltrating ductal carcinoma (IDC) (n = 232,647). The demographics and tumour and treatment characteristics of IPC were compared to those of IDC. A Cox proportional hazards model was used to investigate the effects of baseline characteristics on disease-specific survival (DSS). We performed a 1:1 (IPC: IDC) matched case-control analysis using the propensity score-matching method. A forest plot of hazard ratios (HRs) that was used to illustrate the exploratory subgroup analyses. Results Generally, IPCs occurred in older women (≥50 years old) and presented with smaller sizes, lower grades, higher rates of oestrogen receptor (ER) and progesterone receptor (PR) positivity, and reduced lymph node (LN) involvement and were less likely to be treated with mastectomy than patients with IDC. The five-year DSS rates were significantly better in IPC than in IDC (97.5% vs. 93%, respectively; P Conclusions This study is currently the largest analysis of IPC. We investigated a large cohort of patients with IPC and found that this rare tumour type presents unique clinicopathological characteristics and is associated with a higher rate of breast-conserving surgery and favourable prognoses than are observed in the overall IDC population. However, this advantage was diminished after we adjusted for demographic and clinicopathological factors. Therefore, patients diagnosed with this rare variant should be made aware that its biological features are not as favourable as once thought. Therapeutic decisions should not be made based solely on this rare entity and evidence-based treatment guidelines should be strictly followed. Improving our understanding of the clinical and biological features of IPC may lead to more individualized and tailored therapies for breast cancer patients. Citation Format: Zheng Y-Z, Hu X, Shao Z-M. Clinicopathological characteristics and survival outcomes in invasive papillary carcinoma of the breast: A population-based study [abstract]. In: Proceedings of the 2016 San Antonio Breast Cancer Symposium; 2016 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2017;77(4 Suppl):Abstract nr P6-09-29.

Abstract P6-04-04: Comprehensive transcriptome analysis identifies novel molecular subtypes and subtype-specific lncRNAs of triple-negative breast cancer

Background: Triple-negative breast cancer (TNBC) is a highly heterogeneous group of cancers with no effective therapeutic targets hitherto. Thus molecular subtyping is necessary to better identify molecular-based therapies. While some classifiers have been established, no one has integrated the expression profiles of long-noncoding RNAs (lncRNAs) into such subtyping criterions. Considering the emerging important role of lncRNAs in gene regulation and other cellular processes, a novel classification integrating the transcriptome profiles of both messenger RNA (mRNA) and lncRNA would help us better understand the heterogeneity of TNBC and treat patients accordingly. Methods: Using human transcriptome microarray, we retrieved the transcriptome profiles of 165 consecutive TNBC samples. We used k-means clustering to classify the samples based on the most differentially expressed genes (standard deviation>0.65). Empirical cumulative distribution function was analyzed to determine the optimal number of subtypes. Then the new classifier was compared with the Lehmann/Pietenpol system, and survival analyses were performed to compare the recurrence-free survival (RFS) in different subtypes. Gene Ontology (GO) and pathway analyses were applied to determine the main function of the subtype-specific genes and pathways. We conducted co-expression network analysis to identify interactions between lncRNAs and mRNAs, and to predict possible functions of subtype specific lncRNAs. Results: All 165 TNBC tumors were classified into four distinct clusters, each displaying unique GOs and pathways. These include an immunomodulatory (IM) subtype, a luminal androgen receptor (LAR) subtype, a mesenchymal-like (MES) subtype and a basal-like and immune suppressed (BLIS) subtype, accounting for 17.0%, 17.6%, 33.3%, and 32.2% of the patients, respectively. The IM subtype had unique GOs and pathways involving immune cell process. The LAR subtype was highly enriched in hormonally regulated pathways. Enriched pathways in the MES subtype included ECM-receptor interaction, focal adhesion, and processes linked to growth factor signaling pathways. The BLIS subtype was characterized by downregulation of immune response gene and activation of cell cycle and DNA repair, and patients in this subtype experienced worse RFS compared to other subtypes (log-rank test,P=0.045), which was in concordance with the highly proliferative and immune-suppressed nature of these tumors. When analyzing the distribution of the Lehmann/Pietenpol subtypes in our classification system, we found that the two classification systems were significantly correlated (P=0.039). However, our novel classification was more concise and significantly connected with survival outcome. Subtype-specific lncRNAs were identified and their possible functions were predicted using co-expression network analysis. Conclusions: We developed a novel TNBC classification system integrating the expression profiles of both mRNAs and lncRNAs, and determined subtype-specific lncRNAs that are potential biomarkers and targets of TNBC. If further validated in larger population, our novel classification system could facilitate patient counseling and individualize treatment of TNBC. Citation Format: Liu Y-R, Jiang Y-Z, Xu X-E, Zuo W-J, Yu K-D, Jin X, Hu X, Wu J, Liu G-Y, Di G-H, Shao Z-M. Comprehensive transcriptome analysis identifies novel molecular subtypes and subtype-specific lncRNAs of triple-negative breast cancer. [abstract]. In: Proceedings of the Thirty-Eighth Annual CTRC-AACR San Antonio Breast Cancer Symposium: 2015 Dec 8-12; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2016;76(4 Suppl):Abstract nr P6-04-04.

Abstract P3-13-06: A prospective phase II trial of vinorelbine plus oxaliplatin in second- or third-line metastatic triple-negative breast cancer

Purpose: Patients with metastatic triple-negative breast cancer (mTNBC) typically have a poor prognosis and limited treatment options. Previous study showed biweekly combination of vinorelbine and oxaliplatin (NVBOX) at doses of 30 mg/m2 and 90 mg/m2, respectively, is highly active and well tolerated as first-line treatment for patients with metastatic breast cancer. The purpose of this study (NCT 01528826) was to prospectively evaluate the efficacy and toxicity of NVBOX in second- or third-line mTNBC. Methods: Eligible patients were female with 18–70 years old and an Eastern Cooperative Oncology Group (ECOG) performance status of 0 to 1, and had mTNBC that had progressed after 1or 2 prior chemotherapy regimens in the metastatic setting. A period of 4 weeks (NVBOX twice) was considered as one treatment cycle and the maximum cycles were 6. The primary endpoint was progression-free survival (PFS). Secondary endpoints included overall survival (OS), objective response rate (ORR), and safety. Results: Between Dec 2011 and Nov 2012, forty-four patients were recruited [median age 47; 77.3% with viceral metastasis, 100% had been exposed to anthracyclines and/or taxanes; 56.8% cis/carbo-platin pretreated for MBC; 38.6% with time to progression (TTP) of 1-2 previous regimens before recruitment ≤ 3 months]. The overall response rate was 31.6% (1 complete response, 11 partial responses) and 10 achieved stable diseases (7 lasting more than 6 months) in 38 evaluable patients. After a median follow-up of 12.8 months, the median PFS and OS were 4.3 (95% CI, 3.6–5.0) months and 12.6 (95% CI, 8.1–17.0) months, respectively. PFS was significantly shorter in patients with disease free interval (DFI) ≤ 1year (HR = 2.10; 95% CI, 1.05–4.21; P = 0.037) and TTP of 1-2 previous regimens before recruitment ≤ 3 months (HR = 3.39; 95% CI, 1.66–6.89; P Conclusion: We conclude that biweekly NVBOX regimen is effective with a good safety profile in the second- or third-line mTNBC, which warrants further investigation in a phase III study. Citation Information: Cancer Res 2013;73(24 Suppl): Abstract nr P3-13-06.

Abstract P2-09-13: Fenofibrate induces apoptosis of triple-negative breast cancer cells via activation of NF-kB pathway

Introduction: There are a lot of unmet needs in patients with triple-negative breast cancer (TNBC). Fenofibrate, a PPAR-α (Peroxisome proliferator-activated receptor alpha) agonist, has been used for decades to treat hypertriglyceridaemia and mixed dyslipidaemia and recent studies showed that it may have anti-tumor effects, however, the mechanism remains unclear. Here, we assessed the ability of fenofibrate to inhibit TNBC cells proliferation and to induce apoptosis in vitro and in vivo and explored possible involved mechanisms. Methods: Utilization of cell count kit-8 method was to evaluate the anti-proliferation effect of fenofibrate. The percentage of apoptotic cells and distribution ratio of cell cycle was determined by flow cytometric analysis. The related protein levels were measured with Western Blotting methods. The inhibition of tumor growth in vivo was assessed using MDA-MB-231 xenograft mouse model. Terminal deoxytransferase-catalyzed DNA nick-end labeling assay was employed to estimate the proportion of apoptotic cells in tumor tissue sections. In order to evaluate the safety of fenofibrate, counts of leukocyte, erythrocyte, hemoglobin, platelet, aspartate transaminase,alanine transaminase and blood urea nitrogen in peripheral blood were detected. Results: Fenofibrate had anti-proliferation effects on the twelve different subtype breast cancer cell lines we studied, of which the first five most sensitive ones were all TNBC cell lines. Its induction of apoptosis of MDA-MB-231 cell lines was independent on PPAR-α status with the highest apoptosis percentage of 48.0% when compared with 4.8% in the control group. It occurred in a both time- and dose-dependent manner accompanied by up-regulation of Bad, down-regulation of Bcl-xl, Survivin and activation of caspase-3 and NF-κB pathway. Interestingly, activation of NF-κB pathway played an important role in the induction of apoptosis by fenofibtate and the apoptosis effect can be almost totally blocked by a NF-κB specific inhibitor, that is pyrrolidine dithiocarbamate(PDTC). In addition, fenofibrate led to cell cycle arrest at G1 phase accompanied by down-regulation of Cyclin D1, Cyclin-dependent kinase4(Cdk4) and up-regulation of p21, p27/Kip1.In vivo, fenofibrate significantly inhibited tumor growth in the MDA-MB-231 xengograft mouse model and induced apoptosis with a good safety profile. Conclusions: Fenofibrate can induce apoptosis in TNBC in vitro and in vivo, and the mechanism is the activation of NF-κB pathway in a PPAR-α independent way, which may serve as a novel therapeutic drug for TNBC therapy. Citation Information: Cancer Res 2013;73(24 Suppl): Abstract nr P2-09-13.

Abstract P1-08-26: Hypertension and phosphorylated vascular endothelial growth factor receptor 2 are potential independent predictive factors for progession-free survival in apatinib-treated advanced breast cancer

Background: Apatinib, one specific tyrosine kinase inhibitor that targets the VEGF receptor 2 was assessed in patients with advanced breast cancer. This substudy was to explore potential predictive and prognostic factors for apatinib-treated breast cancer. Method: 80 patients were enrolled and received a starting dose of apatinib 750 or 500 mg/d in 4-week cycles. Efficacy was assessed according to RECIST 1.1 criteria, toxicity was graded based on the CTC adverse events version 4.0. The analyzed factors included patient-related factors, such as age; tumor-related factors, such as circulating biomarkers determined by multiplex cytokine assay and phosphorylated VEGFR2 by immunostaining; and treatment-related factors, such as adverse events. Cox Proportional Hazard model and Logistic test were performed as multivariate analysis to define the independent prognostic factors. Result: Median PFS was 3.84 months, OS 10.64 months, with 17.5% of objective response rate. The most frequent adverse events were hypertension (66.3% for all grades, 17.5% for grade 3/4), hand-foot skin reaction (HFSR, 62.5% for all grades, 20% for grade 3/4), and proteinuria (61.3% for all grades, 7.5% for grade 3/4). According to univariate analysis, longer PFS was correlated with hypertension (p = 0.011), HFSR (p = 0.018), post-menopause (p = 0.021), less previous chemotherapy (p = 0.021), higher drug trough concentration (p = 0.025), and higher baseline serum sVEGFR2 (p = 0.031). Median PFS was 6.60 and 2.00 m in patients with higher and lower p-VEGFR2 expressions (p = 0.001). According to multivariate regression analysis, hypertension (p = 0.038; HR, 0.583, 95% CI 0.351 - 0.969) and p-VEGFR2 expression level (p = 0.013; HR, 0.404, 95% CI 0.198 - 0.826) were independent predictive factors of PFS. Conclusion: Apatinib showed substantial antitumor activity in patients with heavy-pretreated advanced breast cancer with manageable toxicity. Hypertension and p-VEGFR2 were independent predictive factors for PFS in apatinib-treated advanced breast cancer, and significantly correlated to higher CBR. Citation Information: Cancer Res 2013;73(24 Suppl): Abstract nr P1-08-26.

Abstract P3-07-07: Single nucleotide polymorphisms of BRCA1-interacting genes are associated with triple-negative breast cancer in Chinese Han woman

Aims The mutation of BRCA1 is reported to be linked to the onset of triple negative breast cancer (TNBC). However, the incidence of mutation of BRCA1 in Chinese woman is very low. Recent studies have identified genes that encode proteins that interact with BRCA1 as modifiers of BRCA1-associated breast cancer. We evaluated a comprehensive set of genes that encode most known BRCA1 interactors to evaluate the role of these genes as modifiers of TNBC risk in Chinese Han woman. Methods After a proven by IRB, totally 414 patients with TNBC treated in Fudan University Shanghai Cancer Center and 354 healthy women were recruited in this study. Written informed consents were obtained before their recruitment. The DNA from their peripheral blood were obtained. The single nucleotide polymorphisms (SNPs) investigated in this study were consisted of SNPs reported in literatures, SNPs in function region (exons, intron-exon binding regions, promoters and 5’UTR) with MAF larger than 0.05 and tag SNPs in intron. In addition, SNPs that showed significant deviations ( Results An association was observed between TNBC risk and rs7250266 at BABAM1. The allelic frequency for the G-allele of rs7250266 was 0.19 in controls compared with 0.14 in patients, with significant difference. A comparison of genotyping frequency between cases and controls indicated that GC genotype of rs7250266 were associated with significantly decreased TNBC risk (OR of GC genotype 0.70, 95% CI 0.51-0.97, OR of GG genotype 0.48, 95% CI 0.21-1.07, P = 0.03). Under a dominant model, it9s shown that women with genotypes GC/GG of re7250266 conferred approximately 33% decreased risk to the development of breast cancer (OR 0.67, 95% CI 0.49-0.92, P = 0.01). Another SNP at BABAM1, rs2278256 showed a borderline association with the risk of TNBC. It is also in one linkage disequilibrium (LD) block with rs7250266. Two haplotypes at BABAM1 were demonstrated to be associated with a decrease risk of TNBC. Conclusions We investigated 37 SNPs in 5 BRCA1-associated genes and demonstrated the mutation of rs7250266 was associated with a decrease risk of developing TNBC in Chinese women. It9s the first time this SNP was reported to be associated with breast cancer. Further analysis confirmed haplotypes with mutation of rs7250266 and rs2278256 had a lower risk of developing TNBC than other haplotypes. Citation Information: Cancer Res 2013;73(24 Suppl): Abstract nr P3-07-07.

Abstract P6-11-01: Intermittent High Dose Proton Pump Inhibitor Improves Progression Free Survival as Compared to Standard Chemotherapy in the First Line Treatment of Patients with Metastatic Breast Cancer

Purpose: High dose proton pump inhibitor (PPI) has proved to be potentially effective when combined with chemotherapy in preclinical data. This study (NCT01069081) was designed to investigate whether the efficacy of chemotherapy could be improved with the addition of proton pump inhibitor (PPI) in patients with metastatic breast cancer. Patients and Methods: Females elder than 18 years old with histologically confirmed metastatic breast cancer were eligible for participation. Patients enrolled were randomly assigned to three arms: Arm A, docetaxol 75 mg/m 2 on d4, followed by cisplatin 75 mg/m 2 on d4, repeated every 21 days until maxinum 6 cycles or presence of disease progression or intolerable toxicity; Arm B, the same chemotherapy plus esomeprazole 80 mg p.o. bid three days on and the subsequent four days off, beginning on d1 repeated weekly up to disease progression, intolerable toxicity, patient9s withdrawal, or a maximum of 66 weeks; Arm C, the same as Arm B with the only difference being dose of esomeprazole at 100 mg p.o. bid. The primary endpoint was progression free survival (PFS), and the secondary endpoints were time to progression (TTP), objective response rate (ORR), safety profile, and overall survival (OS). Results: From Aug. 2009 to Dec. 2011, 100 women signed informed consent form (ICF) and 94 patients have undergone at least one injection of chemotherapy. Three patients had severe hypersensitivity reactions, two occurring after the first injection of docetaxol and one in the second cycle. After a median follow up of 17 months, 68 (72.3%) patients got disease progression and 23 (24.5%) patients died. Median PFS for the whole group (n = 94), arm A (n = 33), arm B (n = 30), arm C (n = 31) were 8.9, 7.5, 10.9, and 9.5 months, respectively (p = 0.082). A significant difference was observed between patients who had taken PPI and who not with median PFS of 9.5 and 7.5 months, respectively (p = 0.030). Among 17 patients with triple negative breast cancer, this difference was bigger with median PFS of 9.5 and 3.3 months, respectively (p = 0.014). The overall response rates for the whole group, arm A, arm B, arm C were 58.5%, 51.5%, 63.3%, 61.3%, respectively. Conclusion: This trial is the first randomized study to demonstrate antitumor effects of intermittent high dose PPI in patients with metastatic breast cancer. Docetaxel and cisplatin doublet is comparable to the other first-line chemotherapeutical regimens and the addition of proton pump inhibitor to the doublet improves efficacy with no adding toxicity, especially in patients with triple negative breast cancer. Key Words Proton Pump Inhibitor (PPI), Triple Negative Breast Cancer (TNBC), Phase II Study, Metastatic Breast Cancer, Chemotherapy Citation Information: Cancer Res 2012;72(24 Suppl):Abstract nr P6-11-01.