Citations

Background Lapatinib (L) plus trastuzumab (T) improves outcomes for metastatic human epidermal growth factor 2–positive breast cancer and increases the pathologic complete response in the neoadjuvant setting, but their role as adjuvant therapy remains uncertain. Methods In the Adjuvant Lapatinib and/or Trastuzumab Treatment Optimization trial, patients with centrally confirmed human epidermal growth factor 2–positive early breast cancer were randomly assigned to 1 year of adjuvant therapy with T, L, their sequence (T→L), or their combination (L+T). The primary end point was disease-free survival (DFS), with 850 events required for 80% power to detect a hazard ratio (HR) of 0.8 for L+T versus T. Results Between June 2007 and July 2011, 8,381 patients were enrolled. In 2011, due to futility to demonstrate noninferiority of L versus T, the L arm was closed, and patients free of disease were offered adjuvant T. A protocol modification required P ≤ .025 for the two remaining pairwise comparisons. At a protocol-specified analysis with a median follow-up of 4.5 years, a 16% reduction in the DFS hazard rate was observed with L+T compared with T (555 DFS events; HR, 0.84; 97.5% CI, 0.70 to 1.02; P = .048), and a 4% reduction was observed with T→L compared with T (HR, 0.96; 97.5% CI, 0.80 to 1.15; P = .61). L-treated patients experienced more diarrhea, cutaneous rash, and hepatic toxicity compared with T-treated patients. The incidence of cardiac toxicity was low in all treatment arms. Conclusion Adjuvant treatment that includes L did not significantly improve DFS compared with T alone and added toxicity. One year of adjuvant T remains standard of care.

Purpose We compared efficacy of trastuzumab versus no trastuzumab in patients with small (≤ 2 cm) human epidermal growth factor receptor 2 (HER2) –positive breast cancer treated in randomized trials. Methods A meta-analysis was conducted using data from five of the six adjuvant trastuzumab trials. Efficacy end points were disease-free survival (DFS) and overall survival (OS). Separate analyses were prospectively planned for hormone receptor (HR) –positive and HR-negative cohorts. Random effect models and Yusuf-Peto fixed effects models assessed the impact of heterogeneity on baseline hazards and treatment effects across studies. Peto-Pike cumulative incidence estimates were stratified by study and nodal status. Results Median follow-up time was 8 years. For 2,263 patients with HR-positive disease, 8-year cumulative incidence rates comparing trastuzumab versus no trastuzumab were 17.3% versus 24.3% (P < .001) for DFS and 7.8% versus 11.6% (P = .005) for OS, respectively; for 1,092 HR-positive patients with zero or one positive lymph nodes, results were 12.7% versus 19.4% (P = .005) for DFS and 5.3% versus 7.4% (P = .12) for OS, respectively. For 1,957 patients with HR-negative disease, 8-year cumulative incidence rates were 24.0% versus 33.4% (P < .001) for DFS and 12.4% versus 21.2% (P < .001) for OS, respectively; for 1,040 HR-negative patients with zero or one positive lymph nodes, results were 20.4% versus 26.3% (P = .05) for DFS and 8.2% versus 12.2% (P = .084) for OS, respectively. Conclusion Women with HER2-positive tumors ≤ 2 cm in the randomized trastuzumab trials derived substantial DFS and OS benefit from adjuvant trastuzumab. Trastuzumab-treated patients with HR-positive disease and ≤ one positive lymph node may be candidates for trials assessing less aggressive treatment approaches.

Abstract Neoadjuvant endocrine therapy (ET) in patients (pts) with locally advanced estrogen receptor positive (ER+) breast cancer (BC) improves breast conservation rate, and importantly offers an opportunity for individualized assessment of tumor responsiveness to ET to guide subsequent treatment. Previous neoadjuvant ET trials demonstrated that pathologic tumor size (pT), axillary lymph node status (N), and tumor Ki67 value at surgery predicted risk of relapse. Preoperative endocrine prognostic index (PEPI) was therefore developed to assign risk scores based on these factors. Modified PEPI 0, defined by pT1-2 N0 Ki67&lt; 2.7%, was associated with extremely low risk of recurrence without adjuvant chemotherapy. In addition, high Ki67 post 2-4 weeks (wks) of neoadjuvant ET identified resistant tumors with poor outcome. ALTERNATE trial is a three-arm phase III neoadjuvant/adjuvant ET trial designed to achieve two primary objectives. The first is to prospectively validate that modified PEPI 0 predicts &gt; 95% relapse-free survival (RFS). The second is to determine whether fulvestrant (F), or fulvestrant (F) plus anastrozole (A), is superior to A in inducing a higher rate of modified PEPI 0. Secondary objectives include assessing RFS for pts with endocrine resistant tumor, defined by Ki67 &gt; 10% at 4 or 12 wk, disease progression, or modified PEPI non-0, and pathologic responses of resistant tumors to neoadjuvant chemotherapy. Correlative studies include degrees of Ki67 suppression and ER level post treatment. In addition, ongoing research sequencing studies of DNA and RNA will be performed to contrast sensitive vs resistant tumors. During the first phase of the trial, 1200 pts are randomized 1:1:1 to the F, A or F/A. This provides an 82% chance, 1-sided alpha 0.025 chi-square test to detect at least 10% difference in modified PEPI 0 rate comparing F or F/A with A. While waiting for result of analysis, the A arm will continue for the 2nd phase enrollment. Only the F-containing arm(s) superior over A will be continued to the 2nd phase. During the 2nd phase, an additional 540 pts in each arm is estimated to obtain 317 pts with PEPI score 0. This will have a 90% chance, with a one-sided alpha=0.025 nonparametric Brookmeyer-Crowley type one sample survival test, rejecting that 5 year RFS rate is 95%. The maximum sample size is 2820 pts. Eligible pts include postmenopausal women with newly diagnosed clinical stage II or III ER+ (Allred score 6-8) HER2- BC. Tumor biopsy is required at baseline, 4 wk, and surgery for central Ki67 analysis. Treatment decision is individualized based on 4 wk Ki67 and modified PEPI score. Pts with Ki67 &gt; 10% at 4 wk are switched to chemotherapy. Pts with a modified PEPI score of 0 are recommended not to receive chemotherapy, but continue the assigned ET for 1.5 years followed by 3 years of A. This trial is currently accruing pts through CTSU. This research is supported in part by NCI BIQSFP, and grants from Breast Cancer Research Foundation, Genentech, and the Investigator-Sponsored Study Program of AstraZeneca. The Clinical Trials.gov Identifier: NCT01953588. Citation Format: Cynthia X Ma, Vera Suman, A Marilyn Leitch, Souzan Sanati, Katherine DeSchryver, Gary W Unzeitig, Paul Haluska, Mark Watson, Olwen Hahn, Jo Anne Zujewski, Kelly Hunt, Eric P Winer, Cliff A Hudis, Matthew J Ellis. Alliance A011106: ALTernate approaches for clinical stage II or III Estrogen Receptor positive breast cancer NeoAdjuvant TrEatment (ALTERNATE) in postmenopausal women: A phase III study [abstract]. In: Proceedings of the Thirty-Seventh Annual CTRC-AACR San Antonio Breast Cancer Symposium: 2014 Dec 9-13; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2015;75(9 Suppl):Abstract nr OT2-1-04.

Purpose Positive interim analysis findings from four large adjuvant trials evaluating trastuzumab in patients with early-stage human epidermal growth factor receptor 2 (HER2) –positive breast cancer were first reported in 2005. One of these reports, the joint analysis of North Central Cancer Treatment Group NCCTG N9831 (Combination Chemotherapy With or Without Trastuzumab in Treating Women With HER2-Overexpressing Breast Cancer) and the National Surgical Adjuvant Breast and Bowel Project NSABP B-31 (Doxorubicin and Cyclophosphamide Plus Paclitaxel With or Without Trastuzumab in Treating Women With Node-Positive Breast Cancer That Overexpresses HER2), was updated in 2011. We now report the planned definitive overall survival (OS) results from this joint analysis along with updates on the disease-free survival (DFS) end point. Methods In all, 4,046 patients with HER2-positive operable breast cancer were enrolled to receive doxorubicin and cyclophosphamide followed by paclitaxel with or without trastuzumab in both trials. The required number of events for the definitive statistical analysis for OS (710 events) was reached in September 2012. Updated analyses of overall DFS and related subgroups were also performed. Results Median time on study was 8.4 years. Adding trastuzumab to chemotherapy led to a 37% relative improvement in OS (hazard ratio [HR], 0.63; 95% CI, 0.54 to 0.73; P < .001) and an increase in 10-year OS rate from 75.2% to 84%. These results were accompanied by an improvement in DFS of 40% (HR, 0.60; 95% CI, 0.53 to 0.68; P < .001) and increase in 10-year DFS rate from 62.2% to 73.7%. All patient subgroups benefited from addition of this targeted anti-HER2 agent. Conclusion The addition of trastuzumab to paclitaxel after doxorubicin and cyclophosphamide in early-stage HER2-positive breast cancer results in a substantial and durable improvement in survival as a result of a sustained marked reduction in cancer recurrence.

Abstract Background: Preplanned combined analysis of the National Surgical Adjuvant Breast and Bowel Project (NSABP) B-31 trial and North Central Cancer Treatment Group (NCCTG) (Alliance) N9831 Trial compared adjuvant chemotherapy with or without trastuzumab in women with HER2-positive breast cancer. The initial results were reported in 2005 and updated in early 2011 Methods: 4045 patients with HER2-positive operable breast cancer were enrolled to receive doxorubicin plus cyclophosphamide followed by paclitaxel with or without trastuzumab in both trials. The definitive analysis for OS will occur when 710 events have been reported. Results: Median time on study is 8 years. The required number of events have occurred for the definitive analysis for OS to be conducted by the end of September 2012. Updated analyses of disease free survival and related subgroups will also be presented. Supported by NCI grants U10-CA-12027, -69651, -37377, -69974, -44066, U24-CA-114732, CA25224; Breast Cancer Research Foundation; Genentech 35–03 Citation Information: Cancer Res 2012;72(24 Suppl):Abstract nr S5-5.

Abstract Background Trastuzumab (T) combined with chemotherapy improves survival of women with HER2-positive breast cancer. Dual therapy with T and other HER-2 targeted agents (lapatinib/pertuzumab) has demonstrated improved efficacy compared to T alone in advanced breast cancer, and is in clinical trials in early stage disease. We hypothesize that subgroups of patients with HER2-positive tumors and limited tumor burden (tumor size and no or few positive lymph nodes) have a favorable outcome and would not be candidates for dual therapy. This study will analyze the disease-free survival (DFS)and overall survival (OS) of patients with early stage breast cancer treated with chemotherapy and T in the seminal randomized studies (RCTs). Methods RCTs were identified by a Medline search from 2004-2013. Trial groups from five phase III RCTs agreed to provide data. TrialNumberEligibilityRegimenNSABP B312130T1-3; pN1, pN2a, or pN3a; M0ACx4 then Tx4 VSACx4 then THx4 then Hx40wkNCCTG N98313505T1-3; pN1-2; M0ACx4 then Tx12wk VS ACTx4 then Hx52wk VS ACx4 then Tx12wk then Hx40wkHERA5102T1-3; pN1-2; M0Any (neo)adjuvant regimen, then H q3wk x1yr VS H q3wk x 2yr VS observationFinHER232T1-4; N0-3; M0Vx3 or T*x3 then FECx3 VS Vx3 or T*x3 with Hx9wk then FECx3PACS043010(528 HER2+)T1-3; pN1-2; M0FE(100)Cx6 VSFE(100)Cx6 then Hx1yr VS T*E(75) x6 VS T*E(75) x6 then Hx1yrA, adriamycin; C, cyclophosphamide; T, paclitaxel; T*, docetaxel; H, trastuzumab; P, carboplatin; F, 5-fluorouracil; E, epirubicin; Treatment regimen also included 5 years of hormonal therapy for ER positive patients. The ER+/HER2+ and the ER-/HER2+ cohorts will be analyzed separately. Patients with tumors 3 cm or smaller (T1a, T1b, T1c and &gt;2 cm- 3cm) and 0, 1, 2 and 3 positive lymph nodes will be included. Initially a log rank test will be used to determine if the survival results are different by study. If there is no difference across studies, Kaplan-Meier survival curves with confidence intervals will be estimated. If there is a difference between studies, individual Kaplan-Meier curves will be estimated and the mean of the curves will be estimated along with confidence intervals using the adjusted standard deviation. Estimates at 3, 5 and 8 years will be presented as well as estimates of the event rates within each subpopulation defined by tumor size, number of positive lymph nodes, and ER status. Survival endpoints of DFS, and OS as defined in the original studies will be analyzed. Results and Conclusion Data from the five trials will be analyzed and an abstract provided prior to the meeting. Subgroups of patients with a very favorable outcome when treated with adjuvant chemotherapy and T will be identified. Our survival estimates might serve as benchmarks for future trials evaluating therapy reduction. Our results will complement those of the Dana Farber single arm multicenter trial in patients with “low risk” HER2-positive disease (APT trial; NCT00542451), being submitted to SABCS 2013. Citation Information: Cancer Res 2013;73(24 Suppl): Abstract nr S6-03.

Abstract New approaches to drug development are critically needed to lessen the time, cost, and resources necessary to identify and optimize active agents. Strategies to accelerate drug development include testing drugs earlier in the disease process, such as the neoadjuvant setting. The U.S. Food and Drug Administration (FDA) has issued guidance designed to accelerate drug approval through the use of neoadjuvant studies in which the surrogate short-term endpoint, pathologic response, can be used to identify active agents and shorten the time to approval of both efficacious drugs and biomarkers identifying patients most likely to respond. However, this approach has unique challenges. In particular, issues of patient safety are paramount, given the exposure of potentially curable patients to investigational agents with limited safety experience. Key components to safe drug development in the neoadjuvant setting include defining a study population at sufficiently poor prognosis with standard therapy to justify exposure to investigational agents, defining the extent and adequacy of safety data from phase I, detecting potentially harmful interactions between investigational and standard therapies, improving study designs, such as adaptive strategies, that limit patient exposure to ineffective agents, and intensifying safety monitoring in the course of the trial. The I-SPY2 trial is an example of a phase II neoadjuvant trial of novel agents for breast cancer in which these issues have been addressed, both in the design and conduct of the trial. These adaptations of phase II design enable acceleration of drug development by reducing time and cost to screen novel therapies for activity without compromising safety. Clin Cancer Res; 19(11); 2817–23. ©2013 AACR.

Purpose NCCTG (North Central Cancer Treatment Group) N9831 is the only randomized phase III trial evaluating trastuzumab added sequentially or used concurrently with chemotherapy in resected stages I to III invasive human epidermal growth factor receptor 2–positive breast cancer. Patients and Methods Patients received doxorubicin and cyclophosphamide every 3 weeks for four cycles, followed by paclitaxel weekly for 12 weeks (arm A), paclitaxel plus sequential trastuzumab weekly for 52 weeks (arm B), or paclitaxel plus concurrent trastuzumab for 12 weeks followed by trastuzumab for 40 weeks (arm C). The primary end point was disease-free survival (DFS). Results Comparison of arm A (n = 1,087) and arm B (n = 1,097), with 6-year median follow-up and 390 events, revealed 5-year DFS rates of 71.8% and 80.1%, respectively. DFS was significantly increased with trastuzumab added sequentially to paclitaxel (log-rank P < .001; arm B/arm A hazard ratio [HR], 0.69; 95% CI, 0.57 to 0.85). Comparison of arm B (n = 954) and arm C (n = 949), with 6-year median follow-up and 313 events, revealed 5-year DFS rates of 80.1% and 84.4%, respectively. There was an increase in DFS with concurrent trastuzumab and paclitaxel relative to sequential administration (arm C/arm B HR, 0.77; 99.9% CI, 0.53 to 1.11), but the P value (.02) did not cross the prespecified O'Brien-Fleming boundary (.00116) for the interim analysis. Conclusion DFS was significantly improved with 52 weeks of trastuzumab added to adjuvant chemotherapy. On the basis of a positive risk-benefit ratio, we recommend that trastuzumab be incorporated into a concurrent regimen with taxane chemotherapy as an important standard-of-care treatment alternative to a sequential regimen.

Abstract Identification of HER2 as an important cellular marker in the biology and treatment of breast cancer has highlighted the importance of reliable testing methodology. Controversy exists regarding type of test, reliability, definition of positivity, and which test may best predict for patient (pt) efficacy to anti-HER2 therapies. Purpose: To determine the concordance between HER2 results by 3 central laboratories, impact of round-robin adjudication of discordant cases, and heterogeneity in HER2 results using specimens from 3 adjuvant trials where HER2 testing was performed by local and central laboratories for enrollment. Methods: We performed a blinded round-robin exchange of randomly sampled, HER2-normal (IHC-& FISH-) and HER2-positive breast tumors among 3 central laboratories (NCCTG, BCIRG and NSABP) for confirmatory HER2 testing. The 3 laboratories performed immunohistochemistry (IHC) for HER2 using the HercepTest kit (Dako, Carpenteria, CA) and fluorescence in situ hybridization (FISH) for HER2 using the PathVysion HER2 DNA probe kit/HER2/CEN17 probe mixture (Abbott Molecular, Des Plaines, IL) on 389 tumor specimens obtained from N9831/BCIRG006 (37 IHC+/FISH+, 33 IHC+/FISH-, 36 IHC-/FISH+, 62 IHC-& FISH-) and BCIRG005 (96 IHC-& FISH-); 123 cases had ≥2 blocks examined from the same pt. HER2 positivity was defined according to FDA-approved guidelines used in the clinical trials (IHC+: 3+ complete membrane staining in &gt;10% cells; FISH+: HER2/CEN17 ratio ≥2.0). The HER2 status (IHC: 3+ vs 0-2+; FISH: amplified vs not) for each block was independently determined at each site; discordant IHC and FISH cases were adjudicated at a face-to-face meeting. Results: Independent reads were concordant across pathologists in IHC status in 351/381 (92%) cases and in FISH status in 343/373 (92%) cases. Upon adjudication, a consensus was reached on 16 and 18 of the discordant IHC and FISH cases, respectively. Among 96 BCIRG005 cases, IHC-and FISH-were confirmed in the primary block in all 96 cases. Among 59 evaluable N9831 HER2-normal cases, IHC-and FISH-were confirmed in the primary block in 57 (97%) cases (but another block tested HER2+ for 4 cases). Among 102 N9831/BCIRG006 HER2+ cases, HER2 positivity was confirmed in the primary block in 73 (72%) cases. Among 118 cases with IHC results for &gt; 1 block, the adjudicated IHC result agreed across blocks in 106 (90%) cases. Among 113 cases with FISH results for &gt;1 block, the adjudicated FISH result agreed in 107 (95%) cases. Among 53 N9831 HER2-normal cases adjudicated as IHC-& FISH-(although they all had a previous local HER2+ test), there was significant improvement in disease-free survival associated with trastuzumab given concurrently with paclitaxel after doxorubicin and cyclophosphamide compared to chemotherapy alone (HR=0.31, 95% CI 0.11-0.91; A 23 pts, 10 events; C 30 pts, 5 events). Conclusions: Excellent agreement (96%) was observed among the pathologists at adjudication, suggesting that standardized methods improve assay proficiency. HER2 heterogeneity across blocks was observed more at the protein than at the gene level. In the small subset of N9831 pts adjudicated as HER2-normal trastuzumab benefit was observed. This work was supported by NCI and Genentech. Citation Information: Cancer Res 2010;70(24 Suppl):Abstract nr PD10-02.

Abstract Background: N9831 is the only randomized phase III trial comparing safety and efficacy of the addition of trastuzumab (H) to doxorubicin and cyclophosphamide then paclitaxel (Arm A: AC→T) either following (Arm B: AC→T→H) or starting concurrently with paclitaxel (Arm C: AC→T+H→H) for women with resected Stage I-III invasive HER2+ breast cancer. The 3 yr cumulative incidence of NYHA class III or IV congestive heart failure or sudden cardiac death was previously reported: 3.3% in Arm C, 2.8% in Arm B (Perez EA, et al. JCO 2008). The comparison of AC→T to AC→T+H→H was reported in a joint analysis of N9831 and NSABP B-31 in 2005 and updated in 2007, demonstrating a 52% reduction in risk of a disease event (Romond E et al., NEJM 2005; Perez EA, et al. ASCO 2007).Materials and Methods: Primary endpoint is disease-free survival (DFS). At the second planned interim analysis of Arm A vs. Arm B, the O’Brien-Fleming boundary (OFB) was crossed. NCCTG Independent Data Safety Monitoring Committee approved the release of these data as well as the data pertaining to Arm B vs. Arm C due to slow pace of events [expected 647 events in 4 yr follow-up period (f/u) vs. actual 334 events in 4.5 yr f/u]. Shortly thereafter, there were sufficient events to perform the first planned interim analysis of B vs. C. We present the results of each of these pairwise comparisons taking into account the potential for crossover to Arm C after the release of the joint analysis findings in 2005.Results: From 5/2000 to 4/2005, 2448 eligible women were enrolled for the Arm A (n=1087) vs. Arm B (n=1097) comparison. Median f/u is 5.5 yrs. with 386 events. The addition of trastuzumab sequentially to AC→T significantly improved DFS, univariately [HR(Arm B/Arm A)=0.70, 95% CI: 57-86%, logrank p=0.0005] and after adjusting for age, tumor size, number of positive nodes, and ER [PPH: HRadj=0.67 (95% CI: 0.55-0.82)]. 5 yr DFS was increased from 72% with AC→T to 80% with AC→T →H.From 5/2000 to 4/2005, 1903 eligible women were enrolled for the Arm B (n=954) vs. Arm C (n=949) comparison. Median f/u is 5.3 yrs. with 312 events. The log-rank p-value testing whether DFS differs with respect to starting time of trastuzumab was 0.019. [Not crossing pre-specified OFB for statistical significance]. After adjusting for tumor size, number of positive nodes, and ER, HRadj(Arm C/Arm B)=0.75 (95% CI: 0.60-0.94)]. 5 yr DFS was increased from 80% with AC→T →H to 84% for AC→T+H →H.Conclusions: DFS is significantly improved with the addition of 52 weeks of H (sequentially or concurrently) to AC→ T. There is a statistically significant 33% reduction in the risk of an event with the sequential addition of H following AC→T. There is a strong trend for a 25% reduction in the risk of an event with starting H concurrently with T relative to sequentially after T. Therefore, based on a positive risk/benefit ratio, we recommend that trastuzumab be incorporated in a concurrent fashion with T chemotherapy.Acknowledgements: NIH CA25224, Breast Cancer Research Foundation, Genentech. Citation Information: Cancer Res 2009;69(24 Suppl):Abstract nr 80. NOTE: This abstract was accepted for presentation at the Symposium after the Abstract Book went to press.