Association Between 21-Gene Assay Recurrence Score and Locoregional Recurrence Rates in Patients With Node-Positive Breast Cancer.

Importance: The 21-gene assay recurrence score is increasingly used to personalize treatment recommendations for systemic therapy in postmenopausal women with estrogen receptor (ER)- or progesterone receptor (PR)-positive, node-positive breast cancer; however, the relevance of the 21-gene assay to radiotherapy decisions remains uncertain. Objective: To examine the association between recurrence score and locoregional recurrence (LRR) in a postmenopausal patient population treated with adjuvant chemotherapy followed by tamoxifen or tamoxifen alone. Design, Setting, and Participants: This cohort study was a retrospective analysis of the Southwest Oncology Group S8814, a phase 3 randomized clinical trial of postmenopausal women with ER/PR-positive, node-positive breast cancer treated with tamoxifen alone, chemotherapy followed by tamoxifen, or concurrent tamoxifen and chemotherapy. Patients at North American clinical centers were enrolled from June 1989 to July 1995. Medical records from patients with recurrence score information were reviewed for LRR and radiotherapy use. Primary analysis included 316 patients and excluded 37 who received both mastectomy and radiotherapy, 9 who received breast-conserving surgery without documented radiotherapy, and 5 with unknown surgical type. All analyses were performed from January 22, 2016, to August 9, 2019. Main Outcomes and Measures: The LRR was defined as a recurrence in the breast; chest wall; or axillary, infraclavicular, supraclavicular, or internal mammary lymph nodes. Time to LRR was tested with log-rank tests and Cox proportional hazards regression for multivariate models. Results: The final cohort of this study comprised 316 women with a mean (range) age of 60.4 (44-81) years. Median (interquartile range) follow-up for those without LRR was 8.7 (7.0-10.2) years. Seven LRR events (5.8%) among 121 patients with low recurrence score and 27 LRR events (13.8%) among 195 patients with intermediate or high recurrence score occurred. The estimated 10-year cumulative incidence rates were 9.7% for those with a low recurrence score and 16.5% for the group with intermediate or high recurrence score (P = .02). Among patients who had a mastectomy without radiotherapy (n = 252), the differences in the 10-year actuarial LRR rates remained significant: 7.7 % for the low recurrence score group vs 16.8% for the intermediate or high recurrence score group (P = .03). A multivariable model controlling for randomized treatment, number of positive nodes, and surgical type showed that a higher recurrence score was prognostic for LRR (hazard ratio [HR], 2.36; 95% CI, 1.02-5.45; P = .04). In a subset analysis of patients with a mastectomy and 1 to 3 involved nodes who did not receive radiation therapy, the group with a low recurrence score had a 1.5% rate of LRR, whereas the group with an intermediate or high recurrence score had a 11.1% LRR (P = .051). Conclusions and Relevance: This study found that higher recurrence scores were associated with increased LRR after adjustment for treatment, type of surgical procedure, and number of positive nodes. This finding suggests that the recurrence score may be used, along with accepted clinical variables, to assess the risk of LRR during radiotherapy decision-making.

Clinical and Genomic Risk to Guide the Use of Adjuvant Therapy for Breast Cancer.

BACKGROUND: The use of adjuvant chemotherapy in patients with breast cancer may be guided by clinicopathological factors and a score based on a 21-gene assay to determine the risk of recurrence. Whether the level of clinical risk of breast cancer recurrence adds prognostic information to the recurrence score is not known. METHODS: We performed a prospective trial involving 9427 women with hormone-receptor-positive, human epidermal growth factor receptor 2-negative, axillary node-negative breast cancer, in whom an assay of 21 genes had been performed, and we classified the clinical risk of recurrence of breast cancer as low or high on the basis of the tumor size and histologic grade. The effect of clinical risk was evaluated by calculating hazard ratios for distant recurrence with the use of Cox proportional-hazards models. The initial endocrine therapy was tamoxifen alone in the majority of the premenopausal women who were 50 years of age or younger. RESULTS: The level of clinical risk was prognostic of distant recurrence in women with an intermediate 21-gene recurrence score of 11 to 25 (on a scale of 0 to 100, with higher scores indicating a worse prognosis or a greater potential benefit from chemotherapy) who were randomly assigned to endocrine therapy (hazard ratio for the comparison of high vs. low clinical risk, 2.73; 95% confidence interval [CI], 1.93 to 3.87) or to chemotherapy plus endocrine (chemoendocrine) therapy (hazard ratio, 2.41; 95% CI, 1.66 to 3.48) and in women with a high recurrence score (a score of 26 to 100), all of whom were assigned to chemoendocrine therapy (hazard ratio, 3.17; 95% CI, 1.94 to 5.19). Among women who were 50 years of age or younger who had received endocrine therapy alone, the estimated (±SE) rate of distant recurrence at 9 years was less than 5% (≤1.8±0.9%) with a low recurrence score (a score of 0 to 10), irrespective of clinical risk, and 4.7±1.0% with an intermediate recurrence score and low clinical risk. In this age group, the estimated distant recurrence at 9 years exceeded 10% among women with a high clinical risk and an intermediate recurrence score who received endocrine therapy alone (12.3±2.4%) and among those with a high recurrence score who received chemoendocrine therapy (15.2±3.3%). CONCLUSIONS: Clinical-risk stratification provided prognostic information that, when added to the 21-gene recurrence score, could be used to identify premenopausal women who could benefit from more effective therapy. (Funded by the National Cancer Institute and others; ClinicalTrials.gov number, NCT00310180.).

Germline Genetic Variants in GATA3 and Breast Cancer Treatment Outcomes in SWOG S8897 Trial and the Pathways Study.

INTRODUCTION: GATA3 is a critical transcription factor in maintaining the differentiated state of luminal mammary epithelial cells. We sought to determine the prognostic and predictive roles of GATA3 genotypes for breast cancer. PATIENTS AND METHODS: Twelve single nucleotide polymorphisms (SNPs) were genotyped in 2 breast cancer cohorts, including the SWOG S8897 trial where patients were treated with adjuvant chemotherapy (CAF [cyclophosphamide, doxorubicin, 5-fluorouracil] vs. CMF [cyclophosphamide, methotrexate, 5-fluorouracil]) or untreated, and the observational Pathways Study. RESULTS: In the S8897 trial, rs3802604 and rs568727 were associated with disease-free survival and overall survival in the treated group, regardless of chemotherapy regimen. The GG genotype of rs3802604 conferred poorer overall survival (adjusted hazard ratio, 2.45; 95% confidence interval, 1.48-4.05) and disease-free survival (adjusted hazard ratio, 1.95; 95% confidence interval, 1.27-2.99) compared with the AA genotype. Similar associations were found for rs568727. In contrast, no association with either SNP was found in the untreated group. Subgroup analyses indicated that these 2 SNPs more strongly influenced outcomes in the patients who also received tamoxifen. However, the associations in the subgroup with tamoxifen treatment were not replicated in the Pathways Study, possibly owing to substantial differences between the 2 patient cohorts, such as chemotherapy regimen and length of follow-up. Results from joint analyses across these 2 cohorts were marginally significant, driven by the results in S8897. Bioinformatic analyses support potential functional disruption of the GATA3 SNPs in breast tissue. CONCLUSIONS: The present study provides some evidence for the predictive value of GATA3 genotypes for breast cancer adjuvant therapies. Future replication studies in appropriate patient populations are warranted.

Communicating Risks of Adjuvant Chemotherapy for Breast Cancer: Getting Beyond the Laundry List.

PURPOSE: According to the Institute of Medicine, high-quality cancer care should include effective communication between clinicians and patients about the risks and benefits, expected response, and impact on quality of life of a recommended therapy. In the delivery of oncology care, the barriers to and facilitators of communication about potential long-term and late effects, post-treatment expectations, and transition to survivorship care have not been fully defined. PATIENTS AND METHODS: We collected qualitative data through semistructured interviews with medical oncologists and focus groups with breast cancer survivors and applied the Theoretical Domains Framework to systematically analyze and identify the factors that may influence oncologists' communication with patients with breast cancer about the long-term and late effects of adjuvant therapy. RESULTS: Eight key informant interviews with medical oncologists and two focus groups with breast cancer survivors provided data. Both oncologists and patients perceived information on long-term effects as valuable in terms of improved clinical communication but had concerns about the feasibility of inclusion before treatment. They described the current approaches to communication of therapy risks as a brief laundry list that emphasized acute adverse effects and minimized more long-term issues. We describe the barriers to communication about potential long-term effects from the perspectives of both groups. CONCLUSION: This study provides insight into oncologists' communication with patients with breast cancer regarding the potential long-term and late effects of adjuvant chemotherapy and about setting realistic expectations for life after treatment. Opportunities to improve oncologists' communication about the potential toxicities of therapy, particularly regarding long-term and late effects, should be examined further.

Adjuvant Chemotherapy Guided by a 21-Gene Expression Assay in Breast Cancer.

BACKGROUND: The recurrence score based on the 21-gene breast cancer assay predicts chemotherapy benefit if it is high and a low risk of recurrence in the absence of chemotherapy if it is low; however, there is uncertainty about the benefit of chemotherapy for most patients, who have a midrange score. METHODS: We performed a prospective trial involving 10,273 women with hormone-receptor-positive, human epidermal growth factor receptor 2 (HER2)-negative, axillary node-negative breast cancer. Of the 9719 eligible patients with follow-up information, 6711 (69%) had a midrange recurrence score of 11 to 25 and were randomly assigned to receive either chemoendocrine therapy or endocrine therapy alone. The trial was designed to show noninferiority of endocrine therapy alone for invasive disease-free survival (defined as freedom from invasive disease recurrence, second primary cancer, or death). RESULTS: Endocrine therapy was noninferior to chemoendocrine therapy in the analysis of invasive disease-free survival (hazard ratio for invasive disease recurrence, second primary cancer, or death [endocrine vs. chemoendocrine therapy], 1.08; 95% confidence interval, 0.94 to 1.24; P=0.26). At 9 years, the two treatment groups had similar rates of invasive disease-free survival (83.3% in the endocrine-therapy group and 84.3% in the chemoendocrine-therapy group), freedom from disease recurrence at a distant site (94.5% and 95.0%) or at a distant or local-regional site (92.2% and 92.9%), and overall survival (93.9% and 93.8%). The chemotherapy benefit for invasive disease-free survival varied with the combination of recurrence score and age (P=0.004), with some benefit of chemotherapy found in women 50 years of age or younger with a recurrence score of 16 to 25. CONCLUSIONS: Adjuvant endocrine therapy and chemoendocrine therapy had similar efficacy in women with hormone-receptor-positive, HER2-negative, axillary node-negative breast cancer who had a midrange 21-gene recurrence score, although some benefit of chemotherapy was found in some women 50 years of age or younger. (Funded by the National Cancer Institute and others; TAILORx ClinicalTrials.gov number, NCT00310180 .).

Accuracy of the online prognostication tools PREDICT and Adjuvant! for early-stage breast cancer patients younger than 50 years.

IMPORTANCE: Online prognostication tools such as PREDICT and Adjuvant! are increasingly used in clinical practice by oncologists to inform patients and guide treatment decisions about adjuvant systemic therapy. However, their validity for young breast cancer patients is debated. OBJECTIVE: To assess first, the prognostic accuracy of PREDICT's and Adjuvant! 10-year all-cause mortality, and second, its breast cancer-specific mortality estimates, in a large cohort of breast cancer patients diagnosed <50 years. DESIGN: Hospital-based cohort. SETTING: General and cancer hospitals. PARTICIPANTS: A consecutive series of 2710 patients without a prior history of cancer, diagnosed between 1990 and 2000 with unilateral stage I-III breast cancer aged <50 years. MAIN OUTCOME MEASURES: Calibration and discriminatory accuracy, measured with C-statistics, of estimated 10-year all-cause and breast cancer-specific mortality. RESULTS: Overall, PREDICT's calibration for all-cause mortality was good (predicted versus observed) meandifference: -1.1% (95%CI: -3.2%-0.9%; P = 0.28). PREDICT tended to underestimate all-cause mortality in good prognosis subgroups (range meandifference: -2.9% to -4.8%), overestimated all-cause mortality in poor prognosis subgroups (range meandifference: 2.6%-9.4%) and underestimated survival in patients < 35 by -6.6%. Overall, PREDICT overestimated breast cancer-specific mortality by 3.2% (95%CI: 0.8%-5.6%; P = 0.007); and also overestimated it seemingly indiscriminately in numerous subgroups (range meandifference: 3.2%-14.1%). Calibration was poor in the cohort of patients with the lowest and those with the highest mortality probabilities. Discriminatory accuracy was moderate-to-good for all-cause mortality in PREDICT (0.71 [95%CI: 0.68 to 0.73]), and the results were similar for breast cancer-specific mortality. Adjuvant!'s calibration and discriminatory accuracy for both all-cause and breast cancer-specific mortality were in line with PREDICT's findings. CONCLUSIONS: Although imprecise at the extremes, PREDICT's estimates of 10-year all-cause mortality seem reasonably sound for breast cancer patients <50 years; Adjuvant! findings were similar. Prognostication tools should be used with caution due to the intrinsic variability of their estimates, and because the threshold to discuss adjuvant systemic treatment is low. Thus, seemingly insignificant mortality overestimations or underestimations of a few percentages can significantly impact treatment decision-making.

The EORTC 10041/BIG 03-04 MINDACT trial is feasible: results of the pilot phase.

BACKGROUND: The MINDACT (Microarray In Node-negative and 1-3 node positive Disease may Avoid ChemoTherapy) trial investigates the clinical utility of the 70-gene profile (MammaPrint) for the selection of breast cancer patients for adjuvant chemotherapy (CT) together with standard clinicopathological criteria. We present the results of the pilot phase consisting of first 800 patients included. METHODS: MINDACT has enrolled 6600 patients, classified into high or low risk by MammaPrint and clinicopathological risk through Adjuvant! Online. Patients with both clinical (C) and genomic (G) high risks are offered adjuvant CT; those with both C and G low risks do not receive CT; patients with discordant risk are randomised for the decision of adjuvant CT based on C or G risk. CT randomisation of anthracycline-based versus docetaxel/capecitabine and endocrine therapy randomisation between letrozole and tamoxifen→letrozole are offered. RESULTS: During the pilot phase 46% of screened patients were enrolled. Main reasons for non-enrolment were node positivity before trial amendment, sample quality problems and failure to meet logistic settings. Among the 800 patients, 386 (48%) were C-low/G-low, 198 (24.8%) as C-high/G-high, 75 (9.4%) as C-low/G-high and 141 (17.6%) as C-high/G-low. In total 216 (27%) cases were discordant. The difference between patients with C-high (42%) and G-high risk (34%) is 8.25% (95% confidence interval (CI), 4.7-11.8%; P<.0001). Compliance with the treatment decision was high (>92%). CONCLUSIONS: The logistically complex MINDACT trial is feasible in a multinational setting. The proportion of discordant patients, the potential reduction in CT by using the genomic signature and compliance to treatment assignment are in accordance with the trial hypotheses.

Cancer and Leukemia Group B Pathology Committee guidelines for tissue microarray construction representing multicenter prospective clinical trial tissues.

Practice-changing evidence requires confirmation, preferably in multi-institutional clinical trials. The collection of tissue within such trials has enabled biomarker studies and evaluation of companion diagnostic tests. Tissue microarrays (TMAs) have become a standard approach in many cooperative oncology groups. A principal goal is to maximize the number of assays with this precious tissue. However, production strategies for these arrays have not been standardized, possibly decreasing the value of the study. In this article, members of the Cancer and Leukemia Group B Pathology Committee relay our experiences as array facility directors and propose guidelines regarding the production of high-quality TMAs for cooperative group studies. We also discuss statistical issues arising from having a proportion of patients available for TMAs and the possibility that patients with TMAs fail to represent the greater study population.

Independent prognostic value of screen detection in invasive breast cancer.

BACKGROUND: Mammographic screening has led to a proportional shift toward earlier-stage breast cancers at presentation. We assessed whether the method of detection provides prognostic information above and beyond standard prognostic factors and investigated the accuracy of predicted overall and breast cancer-specific survival by the computer tool Adjuvant! among patients with screen-detected, interval, and nonscreening-related carcinomas. METHODS: We studied 2592 patients with invasive breast cancer who were treated at the Netherlands Cancer Institute from January 1, 1990, through December 31, 2000. Overall and breast cancer-specific survival probabilities among patients with mammographically screen-detected (n = 958), interval (n = 417), and nonscreening-related (n = 1217) breast carcinomas were compared. Analyses were adjusted for clinicopathologic characteristics and adjuvant systemic therapy. Because of gradual implementation of population-based screening in the Netherlands, analyses were stratified a priori according to two periods of diagnosis. All statistical tests were two-sided. RESULTS: Screen detection was associated with reduced mortality (adjusted hazard ratio for all-cause mortality = 0.74, 95% confidence interval = 0.63 to 0.87, P < .001, and adjusted hazard ratio for breast cancer-specific mortality = 0.62, 95% confidence interval = 0.50 to 0.78, P < .001, respectively) compared with nonscreening-related detection. The absolute adjusted reduction in breast cancer-specific mortality was 7% at 10 years. The prognostic value of the method of detection was independent of the period of diagnosis and was similar across tumor size and lymph node status categories, indicating its prognostic value beyond stage migration. Adjuvant! underestimated breast cancer-specific survival in patients with screen-detected (-3.2%) and interval carcinomas (-5.4%). CONCLUSIONS: Screen detection was found to be independently associated with better prognosis for overall and breast cancer-specific survival and to provide prognostic information beyond stage migration among patients with invasive breast cancer. We propose that the method of detection should be taken into account when estimating individual prognosis.

Gene polymorphisms in cyclophosphamide metabolism pathway,treatment-related toxicity, and disease-free survival in SWOG 8897 clinical trial for breast cancer.

PURPOSE: There are no established genetic markers for prediction of outcomes after cyclophosphamide (CP)-containing adjuvant therapy for breast cancer. In an ancillary study to a SWOG (Southwest Oncology Group) trial (S8897), we investigated functional polymorphisms in 4 genes in CP pharmacokinetic pathways in relation to hematologic toxicity and disease-free survival (DFS). EXPERIMENTAL DESIGN: Germline DNA was available from 458 women who were at high risk of relapse and was randomized to CAF (CP, intravenous doxorubicin, and 5-fluorouracil) versus CMF (CP, intravenous methotrexate, and 5-fluorouracil) ± tamoxifen, and from 874 women who had a presumed favorable prognosis and did not receive adjuvant therapy. Odds ratios for grade 3 and 4 hematologic toxicity in the treated group and hazard ratios for DFS associated with selected functional polymorphisms in CYP2B6CYP3A4GSTA1 and GSTP1 were estimated by logistic regression and Cox proportional hazard regression. RESULTS: Compared with women with AA genotypes, those with at least 1 GSTP1 variant G allele had reduced risk of grade 3 and 4 neutropenia [odds ratios (OR) = 0.63, 95% CI = 0.41-0.97] and leucopenia (OR = 0.59, 95% CI = 0.39-0.89). No other associations between single nucleotide polymorphisms and toxicity or survival were found in the treated or untreated group. CONCLUSION: Known genetic variants in genes involved in CP pharmacokinetics may not have major effects on DFS in breast cancer patients. The lower risk of developing high-grade hematologic toxicity among women with variant GSTP1 alleles suggests that genetic markers in combination with clinical factors may be useful in defining a subgroup of women who are less susceptible to adverse hematologic toxicities with CP-containing therapies.

Estrogen plus progestin and breast cancer incidence and mortality in postmenopausal women.

CONTEXT: In the Women's Health Initiative randomized, placebo-controlled trial of estrogen plus progestin, after a mean intervention time of 5.6 (SD, 1.3) years (range, 3.7-8.6 years) and a mean follow-up of 7.9 (SD, 1.4) years, breast cancer incidence was increased among women who received combined hormone therapy. Breast cancer mortality among participants in the trial has not been previously reported. OBJECTIVE: To determine the effects of therapy with estrogen plus progestin on cumulative breast cancer incidence and mortality after a total mean follow-up of 11.0 (SD, 2.7) years, through August 14, 2009. DESIGN, SETTING, AND PARTICIPANTS: A total of 16,608 postmenopausal women aged 50 to 79 years with no prior hysterectomy from 40 US clinical centers were randomly assigned to receive combined conjugated equine estrogens, 0.625 mg/d, plus medroxyprogesterone acetate, 2.5 mg/d, or placebo pill. After the original trial completion date (March 31, 2005), reconsent was required for continued follow-up for breast cancer incidence and was obtained from 12,788 (83%) of the surviving participants. MAIN OUTCOME MEASURES: Invasive breast cancer incidence and breast cancer mortality. RESULTS: In intention-to-treat analyses including all randomized participants and censoring those not consenting to additional follow-up on March 31, 2005, estrogen plus progestin was associated with more invasive breast cancers compared with placebo (385 cases [0.42% per year] vs 293 cases [0.34% per year]; hazard ratio [HR], 1.25; 95% confidence interval [CI], 1.07-1.46; P = .004). Breast cancers in the estrogen-plus-progestin group were similar in histology and grade to breast cancers in the placebo group but were more likely to be node-positive (81 [23.7%] vs 43 [16.2%], respectively; HR, 1.78; 95% CI, 1.23-2.58; P = .03). There were more deaths directly attributed to breast cancer (25 deaths [0.03% per year] vs 12 deaths [0.01% per year]; HR, 1.96; 95% CI, 1.00-4.04; P = .049) as well as more deaths from all causes occurring after a breast cancer diagnosis (51 deaths [0.05% per year] vs 31 deaths [0.03% per year]; HR, 1.57; 95% CI, 1.01-2.48; P = .045) among women who received estrogen plus progestin compared with women in the placebo group. CONCLUSIONS: Estrogen plus progestin was associated with greater breast cancer incidence, and the cancers are more commonly node-positive. Breast cancer mortality also appears to be increased with combined use of estrogen plus progestin. TRIAL REGISTRATION: clinicaltrials.gov Identifier: NCT00000611.

The lack, need, and opportunities for decision-making and informational tools to educate primary-care physicians and women about breast cancer chemoprevention.

This perspective on Vogel et al. (beginning on page 696 in this issue of the journal) examines tamoxifen and raloxifene prescription patterns and why these agents are little used for breast cancer prevention despite their effectiveness in definitive trials, Food and Drug Administration approval, and American Society of Clinical Oncology Guidelines Committee endorsement for this purpose. The complexity of weighing the positive and negative aspects of the drugs and estimating net benefit is discussed, as is the need for informational resources such as interactive Internet-based tools to allow better individualized decisions about the options for chemoprevention.

Manganese superoxide dismutase polymorphism, treatment-related toxicity and disease-free survival in SWOG 8897 clinical trial for breast cancer.

To date, the few studies of associations between a functional polymorphism in the oxidative stress-related gene manganese superoxide dismutase (SOD2) and breast cancer survival have been inconsistent. In a homogeneous patient population from a large cooperative group trial Southwest Oncology Group (SWOG) 8897, we evaluated this polymorphism in relation to both treatment-related toxicity and disease-free survival (DFS). Among 458 women who received cyclophosphamide-containing adjuvant chemotherapy, those with variant C alleles, related to higher antioxidant activity, experienced less grade 3-4 neutropenia (OR = 0.52, 95% CI = 0.29-0.92) but had worse DFS (HR = 1.59, 95% CI = 0.99-2.55) than women with TT genotypes. No associations were observed among 874 women who were followed without adjuvant therapy. Our results are consistent with the hypothesis that women with higher SOD2 antioxidant activity may experience less treatment-related toxicity but shorter time to disease recurrence or death after breast cancer adjuvant chemotherapy, supporting the modifying effects of oxidative stress-related enzymes on cancer treatment toxicity and efficacy.

Ki67 in breast cancer: prognostic and predictive potential.

The leading parameters that define treatment recommendations in early breast cancer are oestrogen-receptor, progesterone-receptor, and human epidermal growth-factor status. Although some pathologists report Ki67 in addition to other biological markers, the existing guidelines of the American Society of Clinical Oncology do not include Ki67 in the list of required routine biological markers. The advent of new genetic tests has emphasised the role of proliferative genes, including Ki67, as prognostic and predictive markers. Additionally, randomised studies have retrospectively reviewed data and reported on the role of Ki67 in breast cancer. In light of new data, we have re-assessed evidence that could change guidelines to include Ki67 in the standard pathological assessment of early breast cancers. This review provides an update on the current knowledge on Ki67 and of the evidence in the published work about the prognostic and predictive role of this marker, and provides information on the laboratory techniques used to determine Ki67.

Adjuvant chemotherapy and timing of tamoxifen in postmenopausal patients with endocrine-responsive, node-positive breast cancer: a phase 3, open-label, randomised controlled trial.

BACKGROUND: Tamoxifen is standard adjuvant treatment for postmenopausal women with hormone-receptor-positive breast cancer. We assessed the benefit of adding chemotherapy to adjuvant tamoxifen and whether tamoxifen should be given concurrently or after chemotherapy. METHODS: We undertook a phase 3, parallel, randomised trial (SWOG-8814, INT-0100) in postmenopausal women with hormone-receptor-positive, node-positive breast cancer to test two major objectives: whether the primary outcome, disease-free survival, was longer with cyclophosphamide, doxorubicin, and fluorouracil (CAF) given every 4 weeks for six cycles plus 5 years of daily tamoxifen than with tamoxifen alone; and whether disease-free survival was longer with CAF followed by tamoxifen (CAF-T) than with CAF plus concurrent tamoxifen (CAFT). Overall survival and toxicity were predefined, important secondary outcomes for each objective. Patients in this open-label trial were randomly assigned by a computer algorithm in a 2:3:3 ratio (tamoxifen:CAF-T:CAFT) and analysis was by intention to treat of eligible patients. Groups were compared by stratified log-rank tests, followed by Cox regression analyses adjusted for significant prognostic factors. This trial is registered with ClinicalTrials.gov, number NCT00929591. FINDINGS: Of 1558 randomised women, 1477 (95%) were eligible for inclusion in the analysis. After a maximum of 13 years of follow-up (median 8.94 years), 637 women had a disease-free survival event (tamoxifen, 179 events in 361 patients; CAF-T, 216 events in 566 patients; CAFT, 242 events in 550 patients). For the first objective, therapy with the CAF plus tamoxifen groups combined (CAFT or CAF-T) was superior to tamoxifen alone for the primary endpoint of disease-free survival (adjusted Cox regression hazard ratio [HR] 0.76, 95% CI 0.64-0.91; p=0.002) but only marginally for the secondary endpoint of overall survival (HR 0.83, 0.68-1.01; p=0.057). For the second objective, the adjusted HRs favoured CAF-T over CAFT but did not reach significance for disease-free survival (HR 0.84, 0.70-1.01; p=0.061) or overall survival (HR 0.90, 0.73-1.10; p=0.30). Neutropenia, stomatitis, thromboembolism, congestive heart failure, and leukaemia were more frequent in the combined CAF plus tamoxifen groups than in the tamoxifen-alone group. INTERPRETATION: Chemotherapy with CAF plus tamoxifen given sequentially is more effective adjuvant therapy for postmenopausal patients with endocrine-responsive, node-positive breast cancer than is tamoxifen alone. However, it might be possible to identify some subgroups that do not benefit from anthracycline-based chemotherapy despite positive nodes. FUNDING: National Cancer Institute (US National Institutes of Health).

High risk of recurrence for patients with breast cancer who have human epidermal growth factor receptor 2-positive, node-negative tumors 1 cm or smaller.

PURPOSE: To evaluate the risk of recurrence in women diagnosed with T1a and T1b, node-negative, human epidermal growth factor receptor 2 (HER2) -positive breast cancer. METHODS: We reviewed 965 T1a,bN0M0 breast cancers diagnosed at our institution between 1990 and 2002. Dedicated breast pathologists confirmed HER2 positivity if 3+ by immunohistochemistry or if it had a ratio of 2.0 or greater by fluorescence in situ hybridization (FISH). Patients who received adjuvant chemotherapy or trastuzumab were excluded. Kaplan-Meier product was used to calculate recurrence-free survival (RFS) and distant recurrence-free survival (DRFS). Cox proportional hazard models were fit to determine associations between HER2 status and survival after adjustment for patient and disease characteristics. Additionally, 350 breast cancers from two other institutions were used for validation. RESULTS: Ten percent of patients had HER2-positive tumors. At a median follow-up of 74 months, there were 72 recurrences. The 5-year RFS rates were 77.1% and 93.7% in patients with HER2-positive and HER2-negative tumors, respectively (P < .001). The 5-year DRFS rates were 86.4% and 97.2% in patients with HER2-positive and HER2-negative tumors, respectively (P < .001). In multivariate analysis, patients with HER2-positive tumors had higher risks of recurrence (hazard ratio [HR], 2.68; 95% CI, 1.44 to 5.0; P = .002) and distant recurrence (HR, 5.3; 95% CI, 2.23 to 12.62; P < .001) than those with HER2-negative tumors. Patients with HER2-positive tumors had 5.09 times (95% CI, 2.56 to 10.14; P < .0001) the rate of recurrences and 7.81 times (95% CI, 3.17 to 19.22; P < .0001) the rate of distant recurrences at 5 years compared with patients who had hormone receptor-positive tumors. CONCLUSION: Patients with HER2-positive T1abN0M0 tumors have a significant risk of relapse and should be considered for systemic, anti-HER2, adjuvant therapy.

Calibration and discriminatory accuracy of prognosis calculation for breast cancer with the online Adjuvant! program: a hospital-based retrospective cohort study.

BACKGROUND: Adjuvant! is a web-based program that calculates individualised 10-year survival probabilities and predicted benefit of adjuvant systemic therapy. The Adjuvant! model has not been validated in any large European series. The aim of our study was to validate Adjuvant! in Dutch patients, investigating both its calibration and discriminatory accuracy. METHODS: Patients who were at least partly treated at the Netherlands Cancer Institute for breast cancer between 1987 and 1998 were included if they met the following criteria: tumour size T1 (< or =2 cm), T2 (2-5 cm), or T3 (>5 cm), invasive breast carcinoma, with information about involvement of axillary lymph nodes available, no distant metastases, primary surgery, axillary staging, and radiotherapy according to national guidelines. Clinicopathological characteristics and adjuvant treatment data were retrieved from hospital records and medical registries and were entered into the Adjuvant! (version 8.0) batch processor with blinding to outcome. Endpoints were overall survival and the proportion of patients that did not die from breast cancer (breast-cancer-specific survival [BCSS]). FINDINGS: 5380 patients were included with median follow-up of 11.7 years (range 0.03-21.8). The 10-year observed overall survival (69.0%) and BCSS (78.6%) and Adjuvant! predicted overall survival (69.1%) and BCSS (77.8%) were not statistically different (p=0.87 and p=0.18, respectively). Moreover, differences between predicted and observed outcomes were within 2% for most relevant clinicopathological subgroups. In patients younger than 40 years, Adjuvant! overestimated overall survival by 4.2% (p=0.04) and BCSS by 4.7% (p=0.01). The concordance index, which indicates discriminatory accuracy at the individual level, was 0.71 for BCSS in the entire cohort. INTERPRETATION: Adjuvant! accurately predicted 10-year outcomes in this large-scale Dutch validation study and is of use for adjuvant treatment decision making, although the results may be less reliable in some subgroups.

Myeloperoxidase genotypes and enhanced efficacy of chemotherapy for early-stage breast cancer in SWOG-8897.

PURPOSE: Myeloperoxidase (MPO) generates reactive oxygen species and also activates xenobiotics. In a rigorous clinical trial (Southwest Oncology Group SWOG-8897), we examined relationships between genotypes and disease-free survival (DFS) among women treated for breast cancer, as well as those who did not receive adjuvant chemotherapy. PATIENTS AND METHODS: Patients were assigned to risk groups according to standard prognostic features; the low-risk group (n = 753 genotyped) received follow-up only, and the high-risk group (n = 401 genotyped) was randomly assigned to adjuvant cyclophosphamide, methotrexate, and fluorouracil (CMF) or cyclophosphamide, doxorubicin, and fluorouracil (CAF), with or without tamoxifen. DNA from archived normal lymph node tissue was genotyped, and Cox proportional hazard models were used to calculate DFS associated with MPO genotypes. RESULTS: Among women in the treatment arm, those with MPO G alleles had more than a two-fold reduction in hazard of recurrence (adjusted hazard ratio [HR] for GA genotypes, 0.51; 95% CI, 0.21 to 0.99; HR for GG genotypes, 0.41; 95% CI, 0.21 to 0.77). Effects were greatest among women who were further randomly assigned to tamoxifen (HR for GA genotypes, 0.28; 95% CI, 0.12 to 0.69; HR for GG genotypes, 0.19; 95% CI, 0.08 to 0.45). There were no significant associations between genotypes and DFS among women in the untreated arm, and relationships between genotypes and DFS did not differ by CAF or CMF. CONCLUSION: These results, observed in two independent study populations, indicate that high-activity MPO genotypes are associated with better survival among women receiving cyclophosphamide-containing therapy, particularly when followed by tamoxifen therapy. MPO can be inhibited and/or upregulated by commonly used drugs; thus, our findings merit further investigation for optimization of therapeutics for breast cancer.

Nitric oxide synthase variants and disease-free survival among treated and untreated breast cancer patients in a Southwest Oncology Group clinical trial.

PURPOSE: Numerous chemotherapeutic agents are cytotoxic through generation of reactive species, and variability in genes related to oxidative stress may influence disease-free survival (DFS). We examined relationships between DFS and variants in NOS3, as well as NQO1, NQO2, and CBR3, among treated and untreated breast cancer patients in a Southwest Oncology Group clinical trial (S8897). EXPERIMENTAL DESIGN: In the parent trial, women were assigned according to prognostic features; the high-risk group was randomized to cyclophosphamide, i.v. methotrexate, and 5-fluorouracil or to cyclophosphamide, i.v. doxorubicin, and 5-fluorouracil +/- tamoxifen, and the low-risk group did not receive adjuvant therapy. We extracted DNA from normal lymph node tissue and examined functional polymorphisms in NOS3, NQO1, NQO2, and CBR3, in relation to DFS, using Cox proportional hazard model. RESULTS: There were significant interactions between DFS, adjuvant therapy, and NOS3 Glu298Asp and -786 polymorphisms, alone and in combination (P for interaction = 0.008). When NOS3 genotypes were combined, women with genotypes encoding for lower nitric oxide who received chemotherapy had a >2-fold increase in hazard of progression (hazard ratio, 2.32; 95% confidence interval, 1.26-4.25), whereas there was reduced risk for those who did not receive adjuvant therapy (hazard ratio, 0.42; 95% confidence interval, 0.19-0.95). There were no associations between the other genotypes and DFS in either group. CONCLUSION: Variants encoding lower activity of NOS3 may affect outcomes in breast cancer patients, with the direction of risk differing depending on chemotherapy status. These results may mirror the known dual functions of nitric oxide and nitric oxide synthase, depending on oxidative environment.