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1.  Erratum 
doi:10.1093/jnci/dju192
PMCID: PMC4155433
2.  Erratum 
doi:10.1093/jnci/dju193
PMCID: PMC4155434
3.  Lifetime Cigarette Smoking and Breast Cancer Prognosis in the After Breast Cancer Pooling Project 
Background
There is controversy on whether former smokers have increased risk for breast cancer recurrence or all-cause mortality, regardless of how much they smoked.
Methods
Data were from three US cohorts in the After Breast Cancer Pooling Project, with detailed information on smoking among 9975 breast cancer survivors. Smoking was assessed an average of 2 years after diagnosis. Delayed entry Cox proportional hazards models were used to examine the relationships of smoking status, cigarettes per day, years of smoking, and pack years with breast cancer prognosis. Endpoints included breast cancer recurrence (n = 1727), breast cancer mortality (n = 1059), and overall mortality (n = 1803).
Results
Compared with never smokers, former smokers with less than 20 pack-years of exposure had no increased risk of any outcome. However, former smokers with 20 to less than 34.9 pack-years of exposure had a 22% increased risk of breast cancer recurrence (hazard ratio [HR] = 1.22; 95% confidence interval [CI] = 1.01 to 1.48) and a 26% increased risk of all-cause mortality (HR = 1.26; 95% CI = 1.07 to 1.48). For former smokers with 35 or more pack-years of exposure, the probability of recurrence increased by 37% (HR = 1.37; 95% CI = 1.13 to 1.66), breast cancer mortality increased by 54% (HR = 1.54; 95% CI = 1.24 to 1.91), and all-cause mortality increased by 68% (HR = 1.68; 95% CI = 1.44 to 1.96). Current smoking increased the probability of recurrence by 41% (HR = 1.41; 95% CI = 1.16 to 1.71), increased breast cancer mortality by 60% (HR = 1.61; 95% CI = 1.28 to 2.03), and doubled the risk of all-cause mortality (HR = 2.17; 95% CI = 1.85 to 2.54).
Conclusions
Lifetime cigarette smoking was statistically significantly associated with a poor prognosis among women diagnosed with breast cancer, dose-dependent increased risks of recurrence, and breast cancer and all-cause mortality.
doi:10.1093/jnci/djt359
PMCID: PMC3906992  PMID: 24317179
4.  Investigation of Mammographic Breast Density as a Risk Factor for Ovarian Cancer 
Background
Endogenous hormones and growth factors that increase mammographic breast density could increase ovarian cancer risk. We examined whether high breast density is associated with ovarian cancer risk.
Methods
We conducted a cohort study of 724603 women aged 40 to 79 years with 2506732 mammograms participating in the Breast Cancer Surveillance Consortium from 1995 to 2009. Incident epithelial ovarian cancer was diagnosed in 1373 women. We used partly conditional Cox regression to estimate the association between breast density and 5-year risk of incident epithelial ovarian cancer overall and stratified by 10-year age group. All statistical tests were two-sided.
Results
Compared with women with scattered fibroglandular densities, women with heterogeneously dense and extremely dense breast tissue had 20% and 18% increased 5-year risk of incident epithelial ovarian cancer (hazard ratio [HR] = 1.20, 95% confidence interval [CI] = 1.06 to 1.36; HR = 1.18, 95% CI = 0.93 to 1.50, respectively; P trend = .01). Among women aged 50 to 59 years, we observed a trend in elevated risk associated with increased breast density (P trend = .02); women with heterogeneously and extremely dense breast tissue had 30% (HR = 1.30; 95% CI = 1.03 to 1.64) and 65% (HR = 1.65; 95% CI = 1.12 to 2.44) increased risk, respectively, compared with women with scattered fibroglandular densities. The pattern was similar but not statistically significant at age 40 to 49 years. There were no consistent patterns of breast density and ovarian cancer risk at age 60 to 79 years.
Conclusions
Dense breast tissue was associated with a modest increase in 5-year ovarian cancer risk in women aged 50 to 59 years but was not associated with ovarian cancer at ages 40 to 49 or 60 to 79 years.
doi:10.1093/jnci/djt341
PMCID: PMC3906993  PMID: 24309005
5.  Role of CYB5A in Pancreatic Cancer Prognosis and Autophagy Modulation 
Background
Loss of 18q22.3 is a prognostic marker in pancreatic ductal adenocarcinoma (PDAC). This study investigated genes encoded by this cytoband.
Methods
We studied mRNA/protein expression in radically resected (n = 130) and metastatic patients (n = 50). The role of CYB5A was tested in 11 PDAC cell lines and five primary cultures through retrovirus-mediated upregulation and small interfering RNA using wound-healing, invasion, annexin-V, electron microscopy, and autophagic assays, as well as autophagy genes and kinases arrays. CYB5A+ orthotopic models (n = 6 mice/group) were monitored by Firefly and Gaussia-luciferase bioluminescence, magnetic resonance imaging, and high-frequency ultrasound. Data were analyzed by t test, Fisher exact-test, log-rank test and Cox proportional hazards models. All statistical tests were two-sided.
Results
Both resected and metastatic patients with low mRNA or protein expression of CYB5A had statistically significantly shorter survival (eg, median = 16.7 months, 95% confidence interval [CI] = 13.5 to 19.9; vs median = 24.8 months, 95% CI = 12.8 to 36.9; P = .02, two-sided log-rank test; n = 82 radically resected PDACs), and multivariable analyses confirmed prognostic relevance. Moreover, we characterized a novel function to CYB5A, autophagy induction, concomitant with reduced proliferation and migration/invasion of PDAC cells. Network analysis of proautophagic pathways suggested CYB5A interaction with TRAF6, which was confirmed by TRAF6 downregulation after CYB5A reconstitution (−69% in SU.86.86-CYB5A+; P = .005, two-sided t test). CYB5A silencing had opposite effects, restoring TRAF6 expression and wound healing. In vivo studies showed that CYB5A induced autophagy while inhibiting tumor growth/metastasis and increasing survival (median = 57 days, 95% CI = 52 to 61; vs median = 44 days, 95% CI = 21 to 57; P = .03, two-sided log-rank test).
Conclusions
These results define CYB5A as a novel prognostic factor for PDAC that exerts its tumor-suppressor function through autophagy induction and TRAF6 modulation.
doi:10.1093/jnci/djt346
PMCID: PMC3906994  PMID: 24301457
6.  Factors Contributing to Underuse of Radiation Among Younger Women With Breast Cancer 
Background
Evidence-based literature has confirmed the effectiveness of radiation therapy (RT) after breast-conserving surgery (BCS), especially for young women. However, women with young children may be less likely to be compliant. This study explores factors associated with noncompliance of RT among insured young patients.
Method
Using the MarketScan Database, we identified the study cohort as women aged 20 to 64 years who had a BCS between January 1, 2004, and December 31, 2009, and had continuous enrollment 12 months before and after the date of BCS. Patients who had any radiation claims within a year of BCS were considered compliant. Adjusted odds of compliance were estimated from logistic regressions for the full sample and age-stratified subgroups. Sensitivity analyses were performed to evaluate the robustness of study findings. All statistical tests were two-sided.
Results
Eighteen thousand one hundred twenty of 21 008 (86.25%) nonmetastatic BCS patients received RT. Among patients aged 20 to 64 years, those with children aged 7 to 12 years, those with children aged 13 to 17 years, and those with no children or children aged 18 years or older were more likely to receive RT than patients with at least one child aged less than 7 years (7–12 years: odds ratio (OR) = 1.32, 95% confidence interval (CI) = 1.05 to 1.66, P = .02; 13–17 years: OR = 1.41, 95% CI = 1.13 to 1.75, P = .002; no children or ≥18 years: OR = 1.38, 95% CI = 1.13 to 1.68, P = .001). Stratified analyses showed that the above association was primarily driven by women in the youngest age group (aged 20–50). Other important factors included breast cancer quality of care measures, enrollment in health maintenance organizations or capitated preferred provider organizations, travelled to a Census division outside their residence for BCS, and whether patients were primary holders of the insurance policy.
Conclusions
Competing demands from child care can constitute a barrier to complete guideline-concordant breast cancer therapy. Younger patients may be confronted by unique challenges that warrant more attention in future research.
doi:10.1093/jnci/djt340
PMCID: PMC3937848  PMID: 24317177
7.  An International Ki67 Reproducibility Study 
Background
In breast cancer, immunohistochemical assessment of proliferation using the marker Ki67 has potential use in both research and clinical management. However, lack of consistency across laboratories has limited Ki67’s value. A working group was assembled to devise a strategy to harmonize Ki67 analysis and increase scoring concordance. Toward that goal, we conducted a Ki67 reproducibility study.
Methods
Eight laboratories received 100 breast cancer cases arranged into 1-mm core tissue microarrays—one set stained by the participating laboratory and one set stained by the central laboratory, both using antibody MIB-1. Each laboratory scored Ki67 as percentage of positively stained invasive tumor cells using its own method. Six laboratories repeated scoring of 50 locally stained cases on 3 different days. Sources of variation were analyzed using random effects models with log2-transformed measurements. Reproducibility was quantified by intraclass correlation coefficient (ICC), and the approximate two-sided 95% confidence intervals (CIs) for the true intraclass correlation coefficients in these experiments were provided.
Results
Intralaboratory reproducibility was high (ICC = 0.94; 95% CI = 0.93 to 0.97). Interlaboratory reproducibility was only moderate (central staining: ICC = 0.71, 95% CI = 0.47 to 0.78; local staining: ICC = 0.59, 95% CI = 0.37 to 0.68). Geometric mean of Ki67 values for each laboratory across the 100 cases ranged 7.1% to 23.9% with central staining and 6.1% to 30.1% with local staining. Factors contributing to interlaboratory discordance included tumor region selection, counting method, and subjective assessment of staining positivity. Formal counting methods gave more consistent results than visual estimation.
Conclusions
Substantial variability in Ki67 scoring was observed among some of the world’s most experienced laboratories. Ki67 values and cutoffs for clinical decision-making cannot be transferred between laboratories without standardizing scoring methodology because analytical validity is limited.
doi:10.1093/jnci/djt306
PMCID: PMC3888090  PMID: 24203987
8.  Circulating Inflammation Markers and Prospective Risk for Lung Cancer 
Background
Despite growing recognition of an etiologic role for inflammation in lung carcinogenesis, few prospective epidemiologic studies have comprehensively investigated the association of circulating inflammation markers with lung cancer.
Methods
We conducted a nested case–control study (n = 526 lung cancer patients and n = 592 control subjects) within the Prostate, Lung, Colorectal, and Ovarian Cancer Screening Trial. Control subjects were matched to lung cancer case patients on age, sex, follow-up time (median = 2.9 years), randomization year, and smoking (pack-years and time since quitting). Serum levels of 77 inflammation markers were measured using a Luminex bead-based assay. Conditional logistic regression and weighted Cox models were used to estimate odds ratios (ORs) and cumulative risks, respectively.
Results
Of 68 evaluable markers, 11 were statistically significantly associated with lung cancer risk (P trend across marker categories < .05), including acute-phase proteins (C-reactive protein [CRP], serum amyloid A [SAA]), proinflammatory cytokines (soluble tumor necrosis factor receptor 2 [sTNFRII]), anti-inflammatory cytokines (interleukin 1 receptor antagonist [IL-1RA]), lymphoid differentiation cytokines (interleukin 7 [IL-7]), growth factors (transforming growth factor alpha [TGF-A]), and chemokines (epithelial neutrophil-activating peptide 78 [ENA 78/CXCL5], monokine induced by gamma interferon [MIG/CXCL9], B cell–attracting chemokine 1 [BCA-1/CXCL13], thymus activation regulated chemokine [TARC/CCL17], macrophage-derived chemokine [MDC/CCL22]). Elevated marker levels were associated with increased lung cancer risk, with odds ratios comparing the highest vs the lowest group ranging from 1.47 (IL-7) to 2.27 (CRP). For IL-1RA, elevated levels were associated with decreased lung cancer risk (OR = 0.71; 95% confidence interval = 0.51 to 1.00). Associations did not differ by smoking, lung cancer histology, or latency. A cross-validated inflammation score using four independent markers (CRP, BCA-1/CXCL13, MDC/CCL22, and IL-1RA) provided good separation in 10-year lung cancer cumulative risks among former smokers (quartile [Q] 1 = 1.1% vs Q4 = 3.1%) and current smokers (Q1 = 2.3% vs Q4 = 7.9%) even after adjustment for smoking.
Conclusions
Some circulating inflammation marker levels are associated with prospective lung cancer risk.
doi:10.1093/jnci/djt309
PMCID: PMC3888091  PMID: 24249745
9.  Human Gut Microbiome and Risk for Colorectal Cancer 
We tested the hypothesis that an altered community of gut microbes is associated with risk of colorectal cancer (CRC) in a study of 47 CRC case subjects and 94 control subjects. 16S rRNA genes in fecal bacterial DNA were amplified by universal primers, sequenced by 454 FLX technology, and aligned for taxonomic classification to microbial genomes using the QIIME pipeline. Taxonomic differences were confirmed with quantitative polymerase chain reaction and adjusted for false discovery rate. All statistical tests were two-sided. From 794217 16S rRNA gene sequences, we found that CRC case subjects had decreased overall microbial community diversity (P = .02). In taxonomy-based analyses, lower relative abundance of Clostridia (68.6% vs 77.8%) and increased carriage of Fusobacterium (multivariable odds ratio [OR] = 4.11; 95% confidence interval [CI] = 1.62 to 10.47) and Porphyromonas (OR = 5.17; 95% CI = 1.75 to 15.25) were found in case subjects compared with control subjects. Because of the potentially modifiable nature of the gut bacteria, our findings may have implications for CRC prevention.
doi:10.1093/jnci/djt300
PMCID: PMC3866154  PMID: 24316595
10.  An Epidemiologic and Genomic Investigation Into the Obesity Paradox in Renal Cell Carcinoma 
Background
Obesity increases risk for clear-cell renal cell carcinoma (ccRCC), yet obese patients appear to experience longer survival than nonobese patients. We examined body mass index (BMI) in relation to stage, grade, and cancer-specific mortality (CSM) while considering detection bias, nutritional status, and molecular tumor features.
Methods
Data were available from 2119 ccRCC patients who underwent renal mass surgery at Memorial Sloan-Kettering Cancer Center between 1995 and 2012. Logistic regression models produced associations between BMI and advanced disease. Multivariable competing risks regression models estimated associations between BMI and CSM. Somatic mutation, copy number, methylation, and expression data were examined by BMI among a subset of 126 patients who participated in the Cancer Genome Atlas Project for ccRCC using the Kruskal–Wallis or Fisher exact tests. All statistical tests were two-sided.
Results
Obese and overweight patients were less likely to present with advanced-stage disease compared with normal-weight patients (odds ratio [OR] = 0.61, 95% confidence interval [CI] = 0.48 to 0.79 vs OR = 0.65, 95% CI = 0.51 to 0.83, respectively). Higher BMI was associated with reduced CSM in univariable analyses (P < .005). It remained statistically significant after adjustment for comorbidities and albumin level, but it became non-statistically significant after adjusting for stage and grade (P > .10). Genome-wide interrogation by BMI suggested differences in gene expression of metabolic and fatty acid genes, including fatty acid synthase (FASN), consistent with the obesity paradox.
Conclusions
Our findings suggest that although BMI is not an independent prognostic factor for CSM after controlling for stage and grade, tumors developing in an obesogenic environment may be more indolent.
doi:10.1093/jnci/djt310
PMCID: PMC3866155  PMID: 24285872
11.  Aspirin Use, 8q24 Single Nucleotide Polymorphism rs6983267, and Colorectal Cancer According to CTNNB1 Alterations 
Background
Regular aspirin use reduces the risk for colorectal cancer (CRC), possibly through inhibition of WNT/cadherin-associated protein β1 (CTNNB1 or β-catenin) signaling. The single nucleotide polymorphism (SNP) rs6983267 on chromosome 8q24 is a CRC susceptibility locus that affects binding activity of transcription factor 7 like-2 (TCF7L2) to CTNNB1, thereby altering expression of target oncogenes, including MYC.
Methods
We evaluated regular aspirin use and CRC risk according to genotypes of SNP rs6983267 and CTNNB1 expression status in two prospective case–control studies (840 CRC case patients and 1686 age- and race-matched control subjects) nested within the Nurses’ Health Study and the Health Professionals Follow-up Study. We estimated odds ratios (ORs) and 95% confidence intervals (CIs) using unconditional logistic regression models. All statistical tests were two-sided.
Results
A lower risk of CRC was associated with regular aspirin use and the T allele of rs6983267. The effect of aspirin was confined to individuals with protective T allele of rs6983267 (additive matching factors–adjusted OR for T allele = 0.83; 95% CI = 0.74 to 0.94; P trend = .002; P interaction = .01). Additionally, the T allele of rs6983267 was associated with a reduced expression of MYC oncogene (P trend = .03). Moreover, among individuals with protective T allele, the effect of regular aspirin use was limited to those with positive nuclear CTNNB1 expression. In a functional analysis, in vitro treatment of LS174T cells (a cell line heterozygous for rs6983267) with aspirin was statistically significantly associated with higher G/T allelic ratio of TCF7L2 immunoprecipitated DNA (P = .03).
Conclusions
Our results support an influence of aspirin on WNT/CTNNB1 signaling and suggest that aspirin chemoprevention may be tailored according to rs6983267 genotype.
doi:10.1093/jnci/djt331
PMCID: PMC3866156  PMID: 24317174
12.  Modification of the Association Between Obesity and Lethal Prostate Cancer by TMPRSS2:ERG  
Background
TMPRSS2:ERG is a hormonally regulated gene fusion present in about half of prostate tumors. We investigated whether obesity, which deregulates several hormonal pathways, interacts with TMPRSS2:ERG to impact prostate cancer outcomes.
Methods
The study included 1243 participants in the prospective Physicians’ Health Study and Health Professionals Follow-Up Study diagnosed with prostate cancer between 1982 and 2005. ERG overexpression (a TMPRSS2:ERG marker) was assessed by immunohistochemistry of tumor tissue from radical prostatectomy or transurethral resection of the prostate. Body mass index (BMI) and waist circumference, measured on average 1.3 years and 5.3 years before diagnosis, respectively, were available from questionnaires. Data on BMI at baseline was also available. We used Cox regression to calculate hazard ratios and 95% confidence intervals (CIs). All statistical tests were two-sided.
Results
During a mean follow-up of 12.8 years, 119 men developed lethal disease (distant metastases or prostate cancer death). Among men with ERG-positive tumors, the multivariable hazard ratio for lethal prostate cancer was 1.48 (95% CI = 0.98 to 2.23) per 5-unit increase in BMI before diagnosis, 2.51 (95% CI = 1.26 to 4.99) per 8-inch increase in waist circumference before diagnosis, and 2.22 (95% CI = 1.35 to 3.63) per 5-unit increase in BMI at baseline. The corresponding hazard ratios among men with ERG-negative tumors were 1.10 (95% CI = 0.76 to1.59; P interaction = .24), 1.14 (95% CI = 0.62 to 2.10; P interaction = .09), and 0.78 (95% CI = 0.52 to 1.19; P interaction = .001).
Conclusions
These results suggest that obesity is linked with poorer prostate cancer prognosis primarily in men with tumors harboring the gene fusion TMPRSS2:ERG.
doi:10.1093/jnci/djt332
PMCID: PMC3866157  PMID: 24292212
13.  Racial and Ethnic Differences in Use of Mammography Between Medicare Advantage and Traditional Medicare 
Background
Breast cancer is a leading cause of mortality for women in all racial/ethnic groups. We compared use of mammography by race/ethnicity in Medicare health maintenance organizations (HMOs), preferred provider organizations (PPOs), and traditional Medicare.
Methods
We matched 495 836 women in HMOs and 81 480 women in PPOs who were aged 65 to 69 years during 2009 to women enrolled in traditional Medicare by race/ethnicity, Medicaid eligibility status, and geographic area. We identified mammography use from the Healthcare Effectiveness Data and Information Set for Medicare HMOs and PPOs and from claims data for traditional Medicare with the same specifications. We then compared racial/ethnic differences in rates of mammography in HMOs and PPOs to matched populations in traditional Medicare and estimated differences with z tests. All statistical tests were two-sided.
Results
Relative to matched white women, mammography rates were statistically significantly higher for black, Hispanic, and Asian/Pacific Islander women in HMOs (6.1, 5.4, and 0.9 percentage points, respectively; all P ≤ .003) and statistically significantly lower for all three groups in traditional Medicare (3.3, 7.4, and 7.7 percentage points, respectively; all P < .001). Similar improvements in mammography rates also were observed in PPOs among all minority groups relative to traditional Medicare.
Conclusions
Higher rates of mammography in HMOs and PPOs were associated with a reversal of racial and ethnic differences observed in traditional Medicare. These differences may be related to lower patient cost-sharing and better systems to promote preventive services in managed care plans, as well as unmeasured characteristics or beliefs of minority women who enroll in these health plans relative to those in traditional Medicare.
doi:10.1093/jnci/djt333
PMCID: PMC3866158  PMID: 24316600
15.  Predictive and Prognostic Analysis of PIK3CA Mutation in Stage III Colon Cancer Intergroup Trial 
Background
Somatic mutations in PIK3CA (phosphatidylinositol-4,5-bisphosphonate 3-kinase [PI3K], catalytic subunit alpha gene) activate the PI3K-AKT signaling pathway and contribute to pathogenesis of various malignancies, including colorectal cancer.
Methods
We examined associations of PIK3CA oncogene mutation with relapse, survival, and treatment efficacy in 627 stage III colon carcinoma case subjects within a randomized adjuvant chemotherapy trial (5-fluorouracil and leucovorin [FU/LV] vs irinotecan [CPT11], fluorouracil and leucovorin [IFL]; Cancer and Leukemia Group B 89803 [Alliance]). We detected PIK3CA mutation in exons 9 and 20 by polymerase chain reaction and pyrosequencing. Cox proportional hazards model was used to assess prognostic and predictive role of PIK3CA mutation, adjusting for clinical features and status of routine standard molecular pathology features, including KRAS and BRAF mutations and microsatellite instability (mismatch repair deficiency). All statistical tests were two-sided.
Results
Compared with PIK3CA wild-type cases, overall status of PIK3CA mutation positivity or the presence of PIK3CA mutation in either exon 9 or 20 alone was not statistically significantly associated with recurrence-free, disease-free, or overall survival (log-rank P > .70; P > .40 in multivariable regression models). There was no statistically significant interaction between PIK3CA and KRAS (or BRAF) mutation status in survival analysis (P interaction > .18). PIK3CA mutation status did not appear to predict better or worse response to IFL therapy compared with FU/LV therapy (P interaction > .16).
Conclusions
Overall tumor PIK3CA mutation status is not associated with stage III colon cancer prognosis. PIK3CA mutation does not appear to serve as a predictive tumor molecular biomarker for response to irinotecan-based adjuvant chemotherapy.
doi:10.1093/jnci/djt298
PMCID: PMC3848984  PMID: 24231454
16.  Secular Trends in Colon and Rectal Cancer Relative Survival 
Background
Treatment options for colorectal cancer (CRC) have improved substantially over the past 25 years. Measuring the impact of these improvements on survival outcomes is challenging, however, against the background of overall survival gains from advancements in the prevention, screening, and treatment of other conditions. Relative survival is a metric that accounts for these concurrent changes, allowing assessment of changes in CRC survival. We describe stage- and location-specific trends in relative survival after CRC diagnosis.
Methods
We analyzed survival outcomes for 233965 people in the Surveillance Epidemiology and End Results (SEER) program who were diagnosed with CRC between January 1, 1975, and December 31, 2003. All models were adjusted for sex, race (black vs white), age at diagnosis, time since diagnosis, and diagnosis year. We estimated the proportional difference in survival for CRC patients compared with overall survival for age-, sex-, race-, and period-matched controls to account for concurrent changes in overall survival using two-sided Wald tests.
Results
We found statistically significant reductions in excess hazard of mortality from CRC in 2003 relative to 1975, with excess hazard ratios ranging from 0.75 (stage IV colon cancer; P < .001) to 0.32 (stage I rectal cancer; P < .001), indicating improvements in relative survival for all stages and cancer locations. These improvements occurred in earlier years for patients diagnosed with stage I cancers, with smaller but continuing improvements for later-stage cancers.
Conclusions
Our results demonstrate a steady trend toward improved relative survival for CRC, indicating that treatment and surveillance improvements have had an impact at the population level.
doi:10.1093/jnci/djt299
PMCID: PMC3848985  PMID: 24174654
17.  Predicting Degree of Benefit From Adjuvant Trastuzumab in NSABP Trial B-31 
Background
National Surgical Adjuvant Breast and Bowel Project (NSABP) trial B-31 suggested the efficacy of adjuvant trastuzumab, even in HER2-negative breast cancer. This finding prompted us to develop a predictive model for degree of benefit from trastuzumab using archived tumor blocks from B-31.
Methods
Case subjects with tumor blocks were randomly divided into discovery (n = 588) and confirmation cohorts (n = 991). A predictive model was built from the discovery cohort through gene expression profiling of 462 genes with nCounter assay. A predefined cut point for the predictive model was tested in the confirmation cohort. Gene-by-treatment interaction was tested with Cox models, and correlations between variables were assessed with Spearman correlation. Principal component analysis was performed on the final set of selected genes. All statistical tests were two-sided.
Results
Eight predictive genes associated with HER2 (ERBB2, c17orf37, GRB7) or ER (ESR1, NAT1, GATA3, CA12, IGF1R) were selected for model building. Three-dimensional subset treatment effect pattern plot using two principal components of these genes was used to identify a subset with no benefit from trastuzumab, characterized by intermediate-level ERBB2 and high-level ESR1 mRNA expression. In the confirmation set, the predefined cut points for this model classified patients into three subsets with differential benefit from trastuzumab with hazard ratios of 1.58 (95% confidence interval [CI] = 0.67 to 3.69; P = .29; n = 100), 0.60 (95% CI = 0.41 to 0.89; P = .01; n = 449), and 0.28 (95% CI = 0.20 to 0.41; P < .001; n = 442; P interaction between the model and trastuzumab < .001).
Conclusions
We developed a gene expression–based predictive model for degree of benefit from trastuzumab and demonstrated that HER2-negative tumors belong to the moderate benefit group, thus providing justification for testing trastuzumab in HER2-negative patients (NSABP B-47).
doi:10.1093/jnci/djt321
PMCID: PMC3848987  PMID: 24262440
18.  The Imperative to Address the Cost of Oncology Care 
doi:10.1093/jnci/djt334
PMCID: PMC3848988  PMID: 24226097
19.  Erratum 
doi:10.1093/jnci/djt287
PMCID: PMC3896002
20.  Erratum 
doi:10.1093/jnci/djt286
PMCID: PMC3896001  PMID: 24096623
21.  Prognostic Model Predicting Metastatic Castration-Resistant Prostate Cancer Survival in Men Treated With Second-Line Chemotherapy 
Background
Several prognostic models for overall survival (OS) have been developed and validated in men with metastatic castration-resistant prostate cancer (mCRPC) who receive first-line chemotherapy. We sought to develop and validate a prognostic model to predict OS in men who had progressed after first-line chemotherapy and were selected to receive second-line chemotherapy.
Methods
Data from a phase III trial in men with mCRPC who had developed progressive disease after first-line chemotherapy (TROPIC trial) were used. The TROPIC was randomly split into training (n = 507) and testing (n = 248) sets. Another dataset consisting of 488 men previously treated with docetaxel (SPARC trial) was used for external validation. Adaptive least absolute shrinkage and selection operator selected nine prognostic factors of OS. A prognostic score was computed from the regression coefficients. The model was assessed on the testing and validation sets for its predictive accuracy using the time-dependent area under the curve (tAUC).
Results
The nine prognostic variables in the final model were Eastern Cooperative Oncology Group performance status, time since last docetaxel use, measurable disease, presence of visceral disease, pain, duration of hormonal use, hemoglobin, prostate specific antigen, and alkaline phosphatase. The tAUCs for this model were 0.73 (95% confidence interval [CI] = 0.72 to 0.74) and 0.70 (95% CI = 0.68 to 0.72) for the testing and validation sets, respectively.
Conclusions
A prognostic model of OS in the postdocetaxel, second-line chemotherapy, mCRPC setting was developed and externally validated. This model incorporates novel prognostic factors and can be used to provide predicted probabilities for individual patients and to select patients to participate in clinical trials on the basis of their prognosis. Prospective validation is needed.
doi:10.1093/jnci/djt280
PMCID: PMC3833929  PMID: 24136890
22.  Germline Genetic Contributions to Risk for Esophageal Adenocarcinoma, Barrett’s Esophagus, and Gastroesophageal Reflux 
Background
Esophageal adenocarcinoma (EA) is an increasingly common cancer with poor survival. Barrett’s esophagus (BE) is the main precursor to EA, and every year 0.12% to 0.5% of BE patients progress to EA. BE typically arises on a background of chronic gastroesophageal reflux (GERD), one of the risk factors for EA.
Methods
We used genome-wide association data to investigate the genetic architecture underlying GERD, BE, and EA. We applied a method to estimate the variance explained (array heritability, h2 g) and the genetic correlation (rg) between GERD, BE, and EA by considering all single nucleotide polymorphisms (SNPs) simultaneously. We also estimated the polygenic overlap between GERD, BE, and EA using a prediction approach. All tests were two-sided, except in the case of variance-explained estimation where one-sided tests were used.
Results
We estimated a statistically significant genetic variance explained for BE (h2 g = 35%; standard error [SE] = 6%; one-sided P = 1 × 10−9) and for EA (h2 g = 25 %; SE = 5%; one-sided P = 2 × 10−7). The genetic correlation between BE and EA was found to be high (rg = 1.0; SE = 0.37). We also estimated a statistically significant polygenic overlap between BE and EA (one-sided P = 1 × 10−6), which suggests, together with the high genetic correlation, that shared genes underlie the development of BE and EA. Conversely, no statistically significant results were obtained for GERD.
Conclusions
We have demonstrated that risk to BE and EA is influenced by many germline genetic variants of small effect and that shared polygenic effects contribute to risk of these two diseases.
doi:10.1093/jnci/djt303
PMCID: PMC3833931  PMID: 24168968
23.  The Prostate, Lung, Colorectal, and Ovarian Cancer Screening Trial and Its Associated Research Resource 
The Prostate, Lung, Colorectal, and Ovarian (PLCO) Cancer Screening Trial is a large-scale research effort conducted by the National Cancer Institute. PLCO offers an example of coordinated research by both the extramural and intramural communities of the National Institutes of Health. The purpose of this article is to describe the PLCO research resource and how it is managed and to assess the productivity and the costs associated with this resource. Such an in-depth analysis of a single large-scale project can shed light on questions such as how large-scale projects should be managed, what metrics should be used to assess productivity, and how costs can be compared with productivity metrics. A comprehensive publication analysis identified 335 primary research publications resulting from research using PLCO data and biospecimens from 2000 to 2012. By the end of 2012, a total of 9679 citations (excluding self-citations) have resulted from this body of research publications, with an average of 29.7 citations per article, and an h index of 45, which is comparable with other large-scale studies, such as the Nurses’ Health Study. In terms of impact on public health, PLCO trial results have been used by the US Preventive Services Task Force in making recommendations concerning prostate and ovarian cancer screening. The overall cost of PLCO was $454 million over 20 years, adjusted to 2011 dollars, with approximately $37 million for the collection, processing, and storage of biospecimens, including blood samples, buccal cells, and pathology tissues.
doi:10.1093/jnci/djt281
PMCID: PMC3888207  PMID: 24115361
24.  Statistical and Practical Considerations for Clinical Evaluation of Predictive Biomarkers 
Predictive biomarkers to guide therapy for cancer patients are a cornerstone of precision medicine. Discussed herein are considerations regarding the design and interpretation of such predictive biomarker studies. These considerations are important for both planning and interpreting prospective studies and for using specimens collected from completed randomized clinical trials. Specific issues addressed are differentiation between qualitative and quantitative predictive effects, challenges due to sample size requirements for predictive biomarker assessment, and consideration of additional factors relevant to clinical utility assessment, such as toxicity and cost of new therapies as well as costs and potential morbidities associated with routine use of biomarker-based tests.
doi:10.1093/jnci/djt282
PMCID: PMC3888208  PMID: 24136891
25.  Synbindin in Extracellular Signal-Regulated Protein Kinase Spatial Regulation and Gastric Cancer Aggressiveness 
Background
The molecular mechanisms that control the aggressiveness of gastric cancer (GC) remain poorly defined. Here we show that synbindin contributes to the aggressiveness of GC by activating extracellular signal-regulated protein kinase (ERK) signaling on the Golgi apparatus.
Methods
Expression of synbindin was examined in normal gastric mucosa (n = 44), intestinal metaplastic gastric mucosa (n = 66), and GC tissues (n=52), and the biological effects of synbindin on tumor growth and ERK signaling were detected in cultured cells, nude mice, and human tissue samples. The interaction between synbindin and mitogen-activated protein kinase kinase (MEK1)/ERK was determined by immunofluorescence and fluorescence resonance energy transfer assays. The transactivation of synbindin by nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) was detected using luciferase reporter assay and chromatin immunoprecipitation.
Results
High expression of synbindin was associated with larger tumor size (120.8 vs 44.8cm3; P = .01), advanced tumor node metastasis (TNM) stage (P = .003), and shorter patient survival (hazard ratio = 1.51; 95% confidence interval [CI] = 1.01 to 2.27; P = .046). Synbindin promotes cell proliferation and invasion by activating ERK2 on the Golgi apparatus, and synbindin is directly transactivated by NF-κB. Synbindin expression level was statistically significantly higher in human GCs with activated ERK2 than those with low ERK2 activity (intensity score of 11.5, 95% CI = 10.4 to 12.4 vs intensity score of 4.6, 95% CI 3.9 to 5.3; P < .001). Targeting synbindin in xenograft tumors decreased ERK2 phosphorylation and statistically significantly reduced tumor volume (451.2mm3, 95% CI = 328.3 to 574.1 vs 726.1mm3, 95% CI = 544.2 to 908.2; P = .01).
Conclusions
Synbindin contributes to malignant phenotypes of GC by activating ERK on the Golgi, and synbindin is a potential biomarker and therapeutic target for GC.
doi:10.1093/jnci/djt271
PMCID: PMC4042874  PMID: 24104608

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