Endocrine Therapy Response and 21-Gene Expression Assay for Therapy Guidance in HR+/HER2- Early Breast Cancer.

PURPOSE: To our knowledge, WSG-ADAPT-HR+/HER2- (ClinicalTrials.gov identifier: NCT01779206; n = 5,625 registered) is the first trial combining the 21-gene expression assay (recurrence score [RS]) and response to 3-week preoperative endocrine therapy (ET) to guide systemic therapy in early breast cancer. MATERIALS AND METHODS: Baseline and postendocrine Ki67 (Ki67post) were evaluated centrally. In the endocrine trial, all patients received exclusively ET: patients with pathologic regional lymph node status (pN) 0-1 (ie, 0-3 involved lymph nodes) entered control arm if RS ≤ 11 and experimental arm if RS12-25 with ET response (Ki67post ≤ 10%). All other patients (including N0-1 RS12-25 without ET response) received dose-dense chemotherapy (CT) followed by ET in the CT trial. Primary end point of the endocrine trial was noninferiority of 5-year invasive disease-free survival (5y-iDFS) in experimental (v control) arm; secondary end points included distant DFS, overall survival, and translational research. RESULTS: Intention-to-treat population comprised 2,290 patients (n = 1,422 experimental v n = 868 control): 26.3% versus 34.6% premenopausal and 27.4% versus 24.0% pN1. One-sided 95% lower confidence limit of the 5y-iDFS difference was -3.3%, establishing prespecified noninferiority (P = .05). 5y-iDFS was 92.6% (95% CI, 90.8 to 94.0) in experimental versus 93.9% (95% CI, 91.8 to 95.4) in control arm; 5-year distant DFS was 95.6% versus 96.3%, and 5-year overall survival 97.3% versus 98.0%, respectively. Differences were similar in age and nodal subgroups. In N0-1 RS12-25, outcome of ET responders (ET alone) was comparable with that of ET nonresponders (CT) for age > 50 years and superior for age ≤ 50 years. ET response was more likely with aromatase inhibitors (mostly postmenopausal) than with tamoxifen (mostly premenopausal): 78.1% versus 41.1% (P < .001). ET response was 78.8% in RS0-11, 62.2% in RS12-25, and 32.7% in RS > 25 (n = 4,203, P < .001). CONCLUSION: WSG-ADAPT-HR+/HER2- demonstrates that guiding systemic treatment by both RS and ET response is feasible in clinical routine and spares CT in pre- and postmenopausal patients with ≤ 3 involved lymph nodes.

The run-in phase of the prospective WSG-ADAPT HR+/HER2- trial demonstrates the feasibility of a study design combining static and dynamic biomarker assessments for individualized therapy in early breast cancer.

BACKGROUND: Endocrine sensitivity, as determined by response of the proliferation marker Ki-67 to short-term preoperative endocrine therapy (ET), is currently not included in adjuvant treatment decisions in hormone receptor (HR)+/human epidermal growth factor receptor 2 (HER2)- breast cancer (BC). METHODS: The prospective WSG-ADAPT HR+/HER2- trial included patients with N0/N1 early BC who were candidates for adjuvant chemotherapy based on clinical-pathological criteria alone. The trial utilized a genomic assessment [the Recurrence Score (RS)] plus endocrine sensitivity testing to guide treatment. All patients received 3 (±1) weeks of preoperative induction ET. According to protocol, patients with RS 0-11 or RS 12-25 plus endocrine proliferation response (EPR, post-induction Ki-67 ⩽ 10%) were to be spared adjuvant chemotherapy. RESULTS: The ADAPT HR+/HER2- trial run-in phase included 407 patients with baseline RS, of whom 386 (median age: 54 years) had complete data for Ki-67 at both baseline and post-induction. RS distribution: 23.1% RS 0-11, 58.3% RS 12-25, and 18.7% RS 26-100. EPR occurred in 84.3%, 76.0%, and 36.1% of these RS groups, respectively. Differences in EPR proportions (RS 26-100 versus others, RS 0-11 versus others) were significant (both p < 0.001); Ki-67 quotients were higher for RS 26-100 (p = 0.02, Mann-Whitney). In premenopausal women (n = 146, mostly tamoxifen-treated), median quotient of Ki-67 level (post/pre) was significantly higher than in postmenopausal women (n = 222, mostly aromatase-inhibitor treated; 0.67 versus 0.25, p < 0.001). EPR was significantly associated with baseline estrogen-receptor status as determined by immunohistochemistry (p = 0.002) or real-time polymerase chain reaction (p < 0.001). Also, a strong correlation was observed between RS measured pre- and post-ET (RS = 0.7, n = 181). CONCLUSIONS: This phase of the WSG-ADAPT HR+/HER2- trial confirms trial design estimates of RS and EPR. It indicates that the ADAPT concept of combining static and dynamic biomarker assessment for individualized therapy decisions in early BC is feasible using the EPR criterion post-induction Ki-67 ⩽ 10%. CLINICALTRIALSGOV IDENTIFIER: NCT01779206.

Complete Clinical Response in Locally Advanced Metastatic de novo Breast Cancer after Front-Line Treatment with Ribociclib/Letrozole within the RIBANNA Study.

INTRODUCTION: Ribociclib is an orally bioavailable cyclin-dependent kinase 4/6 inhibitor. In combination with aromatase inhibitor letrozole, it has approval for treatment of hormone receptor positive (HR+) and human epidermal growth factor receptor 2-negative (HER2-) advanced breast cancer. First-line therapy with ribociclib + letrozole significantly improves progression-free survival compared to placebo + letrozole in patients with HR+/HER2- advanced breast cancer. In patients with de novo advanced or metastatic breast cancer, ribociclib was able to provide substantial clinical benefit according to data from the MONALEESA-2 study. CASE PRESENTATION: Here, we report the complete clinical response in a postmenopausal patient with de novo, locally advanced, pulmonary metastatic breast cancer treated with ribociclib + letrozole. Our patient presented an ulcerated breast-consuming tumor with multiple pulmonary metastases. HR+/HER2- breast cancer was confirmed by tumor biopsy. Ki67 expression was 90%. After three months of initial treatment, the tumor-associated ulcerations disappeared, and no measurable pulmonary disease was detectable on CT scan. Treatment was well tolerated, and after dosage reduction due to neutropenia, no further side effects have been documented. At present, complete clinical response remains after 15 months of ongoing treatment. CONCLUSION: This case report documents an exceptional tumor response of a fast growing, locally advanced, pulmonary metastatic HR+/HER2- de novo breast cancer treated by ribociclib/letrozole combination therapy. Treatment success was long lasting with few side effects. The patient was very satisfied with the treatment and had no specific restrictions in her daily life.

Differential impact of prognostic parameters in hormone receptor-positive lobular breast cancer.

BACKGROUND: Invasive lobular breast cancer (BC) is the second most common BC subtype. Prognostic parameters (tumor classification, lymph node status, histologic grade, Oncotype DX recurrence score [RS], progesterone receptor status, and Ki67 index) were retrospectively studied in a large, prospective clinical trial encompassing 2585 patients who had hormone receptor-positive early BC (the West German Study Group PlanB trial). METHODS: BCs were centrally reviewed and classified as lobular (n = 353; 14%) or nonlobular (n = 2232; 86%). The median follow-up was 60 months. Five-year disease-free survival (DFS) estimates were obtained using the Kaplan-Meier method. Prognostic parameters were evaluated using Cox proportional hazard models. RESULTS: Lobular BC was associated with higher tumor classification, higher lymph node status, lower histologic grade, lower Ki67 index, and low or intermediate RS. The prevalence of high RS (RS range, 26-100) was 3-fold lower in patients who had lobular BC compared with those who had nonlobular BC (8% vs 24%; P < .001). However, 5-year DFS estimates for lobular and nonlobular BC were similar (92.1% and 92.3%, respectively; P = .673). In multivariate analyses, prognostic parameters for DFS in lobular BC included grade 3 (hazard ratio, 5.06; 95% CI, 1.91-13.39) and a pathologic lymph node status (pN) of pN3 (hazard ratio, 12.16; 95% CI, 3.87-38.24), but not RS. By contrast, prognostic parameters in nonlobular BC included grade 3 (hazard ratio, 1.65; 95% CI, 1.11-2.44), pN3 (hazard ratio, 3.68; 95% CI, 1.60-8.46), and high RS (hazard ratio, 2.49; 95% CI, 1.69-3.68). CONCLUSIONS: Lobular BC is associated with low and intermediate RS, although 5-year DFS is similar to that of nonlobular BC. The effect of the RS in lobular BC appears to be distinct from that in nonlobular BC. For risk assessment, the RS needs to be complemented by clinicopathologic parameters for therapy decision making.

Association of TILs with clinical parameters, Recurrence Score® results, and prognosis in patients with early HER2-negative breast cancer (BC)-a translational analysis of the prospective WSG PlanB trial.

BACKGROUND: The presence of tumor-infiltrating lymphocytes has been associated with prognosis and chemotherapy response, particularly in high-risk breast cancer subtypes. There is limited data so far as to (i) how tumor-infiltrating lymphocyte (TIL) measurements correlate with genomic measurements such as the Oncotype DX Recurrence Score® and (ii) whether the survival impact of TIL measurements varies according to different adjuvant systemic therapies. METHODS: The WSG PlanB trial compared an anthracycline-free chemotherapy regimen (6x docetaxel/cyclophosphamide, TC) to an anthracycline-taxane sequence (4xEC followed by 4x docetaxel) in patients with intermediate-risk, HER2-negative early breast cancer (EBC). Patients with HR-positive HER2-negative EBC were further stratified to receive endocrine therapy alone vs. chemotherapy followed by endocrine therapy based on Recurrence Score results and nodal status. In this analysis, three independent observers quantified and categorized the presence of TILs among tumor samples from patients in PlanB. TIL measurements were correlated with clinical/pathological parameters and treatment outcome overall and according to the treatment arm. RESULTS: Disease-free survival (DFS) rates were significantly better (p = .04) in HR-negative patients with high vs. intermediate TIL levels and were higher in low vs. intermediate TIL patients, however with borderline significance only (p = .06). There were no significant differences among TIL categories in HR+ patients. High RS categories, HR-negative status, and high KI67 were independently and significantly associated with high TIL categories. There was no significant impact of TIL category on DFS in patients treated by endocrine therapy only; however, in patients receiving chemotherapy, DFS in the intermediate TIL category was lower than that in the other categories. CONCLUSION: Although the presence of high TILs is associated with negative prognostic parameters such as high KI67 and HR-negative status among patients with HR-positive HER2-negative EBC, patients with high TILs show a favorable 5-year DFS in both HR-positive/HER2-negative and triple-negative breast cancer.

West German Study PlanB Trial: Adjuvant Four Cycles of Epirubicin and Cyclophosphamide Plus Docetaxel Versus Six Cycles of Docetaxel and Cyclophosphamide in HER2-Negative Early Breast Cancer.

PURPOSE: The West German Study Group PlanB trial evaluated an anthracycline-free chemotherapy standard (six cycles of docetaxel and cyclophosphamide [TC]) in the routine treatment of human epidermal growth factor receptor 2-negative early breast cancer (EBC). PATIENTS AND METHODS: Patients with pT1 to pT4c, all pN+, and pN0/high-risk EBC were eligible. High-risk pN0 was defined by one or more of the following: pT greater than 2, grade 2 to 3, high urokinase-type plasminogen activator/plasminogen activator inhibitor-1, hormone receptor (HR) negativity, and less than 35 years of age. After an early amendment, all HR-positive tumors underwent recurrence score (RS) testing, with chemotherapy omission recommended in RS less than or equal to 11 pN0 to pN1 disease. Patients were randomly assigned to four cycles of epirubicin (E)90/cyclophoshamide (C)600 followed by four cycles of docetaxel (T)100 or six cycles of T75C600 (administered once every 3 weeks). The primary end point was disease-free survival (DFS); secondary end points were overall survival (OS) and safety. The protocol specified P = .05 for a noninferiority margin of 4.4% for all patients combined. RESULTS: Of the 3,198 registered patients, 348 (RS ≤ 11) omitted chemotherapy, and 401 were not randomly assigned. The intention-to-treat population included 2,449 patients (1,227 EC-T v 1,222 TC: postmenopausal, 62.2% v 60.8%; pN0, 58.2% v 59.5%; pT1, 57.6% v 52.3%; HR positive, 81.4% v 82.2%; RS greater than 25 [in HR-positive patients], 26.2% v 27.5%). Within the safety population (1,167 v 1,178 patients), 87.5% v 93.0% completed therapy. After a 60-month median follow-up, 5-year outcomes were similar in the EC-T and TC arms (DFS, 89.6% [95% CI, 87.9% to 91.5%] v 89.9% [95% CI, 88.1% to 91.8%]; OS, 94.5% [95% CI, 93.1% to 95.9%] v 94.7% [95% CI, 93.3% to 96.1%]). The DFS difference was within the noninferiority margin of the original trial design. Five treatment-related deaths were reported for TC (one for EC-T), despite a trend toward more-severe adverse events in the latter. Interaction analysis revealed no predictive trends with respect to key factors, including triple-negative, luminal A/B-like, pN, age, and RS status. CONCLUSION: In the West German Study Group PlanB trial, 5-year outcomes for TC and EC-T were equally excellent. Six cycles of TC is an effective/safe option in human epidermal growth factor receptor 2-negative EBC with pN0 high genomic risk or pN1 EBC with genomically intermediate- to high-risk disease.

Correction to: Reducing chemotherapy use in clinically high-risk, genomically low-risk pN0 and pN1 early breast cancer patients: five-year data from the prospective, randomised phase 3 West German Study Group (WSG) PlanB trial.

The article Reducing chemotherapy use in clinically high-risk, genomically low-risk pN0 and pN1 early breast cancer patients: five-year data from the prospective, randomised phase 3 West German Study Group (WSG) PlanB trial, written by Ulrike Nitz, Oleg Gluz, Matthias Christgen, Ronald E. Kates, Michael Clemens, Wolfram Malter, Benno Nuding, Bahriye Aktas, Sherko Kuemmel, Toralf Reimer, Andrea Stefek, Fatemeh Lorenz-Salehi, Petra Krabisch, Marianne Just, Doris Augustin, Cornelia Liedtke, Calvin Chao, Steven Shak, Rachel Wuerstlein, Hans H. Kreipe, Nadia Harbeck, was originally published electronically on the publisher's internet portal (currently SpringerLink) on June 29, 2017 without open access.With the author(s)' decision to opt for Open Choice the copyright of the article changed on January 6, 2019 to © The Author(s) 2017 and the article is forthwith distributed under the terms of the Creative Commons Attribution-NonCommercial 4.0 International License ( http://creativecommons.org/licenses/by-nc/4.0/ ), which permits any noncommercial use, duplication, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, a link is provided to the Creative Commons license and any changes made are indicated. The original article has been corrected.

Reducing chemotherapy use in clinically high-risk, genomically low-risk pN0 and pN1 early breast cancer patients: five-year data from the prospective, randomised phase 3 West German Study Group (WSG) PlanB trial.

BACKGROUND: The prospective phase 3 PlanB trial used the Oncotype DX® Recurrence Score® (RS) to define a genomically low-risk subset of clinically high-risk pN0-1 early breast cancer (EBC) patients for treatment with adjuvant endocrine therapy (ET) alone. Here, we report five-year data evaluating the prognostic value of RS, Ki-67, and other traditional clinicopathological parameters. METHODS: A central tumour bank was prospectively established within PlanB. Following an early amendment, hormone receptor (HR)+ , pN0-1 RS ≤ 11 patients were recommended to omit chemotherapy. Patients with RS ≥ 12, pN2-3, or HR-negative/HER2-negative disease were randomised to anthracycline-containing or anthracycline-free chemotherapy. Primary endpoint: disease-free survival (DFS). PlanB Clinicaltrials.gov identifier: NCT01049425. FINDINGS: From 2009 to 2011, PlanB enrolled 3198 patients (central tumour bank, n = 3073) with the median age of 56 years, 41.1% pN+, and 32.5% grade 3 EBC. Chemotherapy was omitted in 348/404 (86.1%) eligible RS ≤ 11 patients. After 55 months of median follow-up, five-year DFS in ET-treated RS ≤ 11 patients was 94% (in both pN0 and pN1) versus 94% (RS 12-25) and 84% (RS > 25) in chemotherapy-treated patients (p < 0.001); five-year overall survival (OS) was 99 versus 97% and 93%, respectively (p < 0.001). Nodal status, central/local grade, tumour size, continuous Ki-67, progesterone receptor (PR), IHC4, and RS were univariate prognostic factors for DFS. In a multivariate analysis including all univariate prognostic markers, only pN2-3, central and local grade 3, tumour size >2 cm, and RS, but not IHC4 or Ki-67 were independent adverse factors. If RS was excluded, IHC4 or both Ki-67 and PR entered the model. The impact of RS was particularly pronounced in patients with intermediate Ki-67 (>10%, <40%) tumours. INTERPRETATION: The excellent five-year outcomes in clinically high-risk, genomically low-risk (RS ≤ 11) pN0-1 patients without adjuvant chemotherapy support using RS with standardised pathology for treatment decisions in HR+ HER2-negative EBC. Ki-67 has the potential to support patient selection for genomic testing.