RANK Expression as an Independent Predictor for Response to Neoadjuvant Chemotherapy in Luminal-Like Breast Cancer: A Translational Insight from the GeparX Trial

PURPOSE

The GeparX study investigated whether denosumab as add-on treatment to nab-paclitaxel-based neoadjuvant chemotherapy (NACT) with two different schedules (125 mg/m² weekly vs. day 1, 8 every 22 days) may increase pathologic complete response (pCR) rate. The addition of denosumab to NACT did not improve pCR rates as recently published. In this study, we investigated whether receptor activator of nuclear factor-kappa B (RANK) expression, as part of the denosumab target pathway: (i) may retrospectively identify a subgroup of patients with additional clinical benefit of denosumab or (ii) may predict response to nab-paclitaxel NACT.

EXPERIMENTAL DESIGN

RANK protein was IHC-stained on pre-therapeutic core biopsies from patients of the GeparX study (n = 667) with the antibody RANK/Envision System HRP (DAB) and was analyzed for the percentage of membranous RANK tumor cell staining (>5% RANKhigh vs. ≤5% RANKlow).

RESULTS

We could not identify any patient subgroup with differential response under denosumab add-on treatment in patients with RANKhigh expression [139/667, 20.8%; OR, 0.86; 95% confidence interval (CI), 0.44-1.68; P = 0.667] or RANKlow expression (528/667 (79.2%) OR, 1.10; 95% CI, 0.78-1.56; P = 0.589; Pinteraction = 0.528). However, the pCR rate was higher in the RANKhigh subgroup compared with RANKlow (50% vs. 39%; OR, 1.52; 95% CI, 1.04-2.21; P = 0.037). RANK expression constituted an independent predictor of response to NACT frequently in patients with luminal-like subtype (HR+/HER2-; OR, 2.98; 95% CI, 1.30-6.79; P = 0.010). No predictive value of RANK expression among the different nab-paclitaxel regimens was observed.

CONCLUSION

We report RANK expression to be an independent predictive biomarker for response to NACT in patients with luminal-like breast cancer.

Identifying breast cancer patients at risk of relapse despite pathological complete response after neoadjuvant therapy

This retrospective pooled analysis aims to identify factors predicting relapse despite a pathologic complete response (pCR) in patients with breast cancer (BC). 2066 patients with a pCR from five neoadjuvant GBG/AGO-B trials fulfill the inclusion criteria of this analysis. Primary endpoint is disease-free survival (DFS); secondary endpoints is distant DFS (DDFS) and overall survival (OS). After a median follow-up of 57.6 months, DFS is significantly worse for patients with positive lymph nodes (cN+ vs cN0 hazard ratio [HR] 1.94, 95%CI 1.48-2.54; p < 0.001). In patients with triple-negative tumors, lobular histology (lobular vs other HR 3.55, 95%CI 1.53-8.23; p = 0.003), and clinical nodal involvement (cN+ vs cN0 HR 2.45, 95%CI 1.59-3.79; p < 0.001) predict a higher risk of DFS events. Patients with HER2-positive cT3/4 tumors have a significantly higher risk of relapse (cT3/4 vs cT1 HR 2.07, 95%CI 1.06-4.03; p = 0.033). Initial tumor load and histological type predict relapse in patients with a pCR.

Abstract PD4-02: PD4-02 Spatial and temporal heterogeneity of predictive and prognostic signatures in triple-negative breast cancer treated with neoadjuvant combination immune-chemotherapy

Background: It is well known that immunological pathways are relevant for response to classical neoadjuvant chemotherapy as well as combined chemo-immunotherapy. In addition, it has been shown that combined chemo-immunotherapy significantly improves survival, even in the context of only moderate effects on pCR. Due to the window therapy with durvalumab-alone and the option to analyze multiple consecutive biopsies, the GeparNuevo trial offers the opportunity to 1) determine gene expression patterns for pCR and DDFS endpoints 2) identify pathways most relevant for pCR and DDFS 3) identify genes specifically regulated by immunotherapy (comparison of samples pre-and post-window) 4) identify genes specifically regulated by chemotherapy (comparison of samples pre-Tx and after 4 cycles of chemotherapy 5) identify longitudinal patterns of gene expression by comparison of up to four time points and 6) identify changes in the tumor microenvironment by spatial sequencing of tumor cell and stroma areas. Methods: 292 tumor samples were evaluated by gene expression analysis: 162 pretherapeutic core biopsies, 79 post-window biopsies, 32 biopsies during chemotherapy and 19 biopsies of the residual tumor after therapy. These samples were analyzed by HTG OBP panel targeting 2549 genes which are assigned to 25 different biological mechanisms or cellular pathways. In addition, spatial profiling was compared in a subset of pre-and post-window samples using Nanostring GeoMx spatial profiling system. Endpoints were pCR and DDFS. Results: A total of more than 600 genes were significantly associated with either the pCR or the DDFS endpoint in either the complete GeparNuevo cohort or one of the two therapy arms. Interestingly, there was a large number of predictive or prognostic genes (n=247 for pCR and n=179 for DDFS) in the durvalumab arm, while the number of genes in the placebo arm was considerably lower (n=113 for pCR and n=61 for DDFS). We used existing pathway information for HTG OBP panel to analyze the contribution of different cellular processes to pCR and DDFS signatures in different therapy arms. Immune pathways were particularly relevant for durvalumab signatures (pCR and DDFS), while cell cycle related gene expression patterns were particularly involved in signatures predictive of pCR in both therapy arms. To further assign genes to the cellular response to durvalumab-alone or chemotherapy-alone, we compared gene expression patterns in durvalumab arm before and after the window phase (gene expression patterns induced by one dose of durvalumab) with gene expression patterns in placebo arm before and after 4 cycles of chemotherapy. Further longitudinal alterations were analyzed by comparison of longitudinal samples for 4 different time-points (a: before NACT, n=162; b: after window phase, n=79; c: after 4 cycles, n=31 and d: at surgery, n=19). Using the Nanostring GeoMx spatial RNA profiling system guided by cytokeratine immunofluorescence, we compared areas with high tumor cell content with stromal areas with or without TILs. In combination with the HTG gene expression data, we were able allocate the changes induced by durvalumab vs chemotherapy to the stromal cell and tumor cell compartment, indicating a re-organization of the tumor-microenvironment. Conclusions: In our analysis, we show that immune gene signatures are particularly relevant for neoadjuvant response to durvalumab as well as prognosis after durvalumab treatment, while proliferation signatures are involved in pCR-signatures after durvalumab as well as chemotherapy. The spatial analysis showed that relevant changes occur in the stromal compartment, indicating a re-organization of the tumor microenvironment. The parallel targeting of immune- and proliferation pathways might explain why a combined immunotherapy-chemotherapy approach is more successful than each single therapy strategy alone.

Citation Format: Carsten Denkert, Andreas Schneeweiss, Julia Rey, Akira Hattesohl, Thomas Karn, Michael Braun, Paul Jank, Jens Huober, Hans-Peter Sinn, Dirk-Michael Zahm, Claus Hanusch, Frederik Marmé, Jenny Furlanetto, Jörg Thomalla, Jens-Uwe Blohmer, Marion van Mackelenbergh, Thorsten Stiewe, Peter Staib, Christian Jackisch, Julia Teply-Szymanski, Peter A. Fasching, Bruno V. Sinn, Michael Untch, Karsten Weber, Sibylle Loibl. PD4-02 Spatial and temporal heterogeneity of predictive and prognostic signatures in triple-negative breast cancer treated with neoadjuvant combination immune-chemotherapy [abstract]. In: Proceedings of the 2022 San Antonio Breast Cancer Symposium; 2022 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2023;83(5 Suppl):Abstract nr PD4-02.

Abstract P4-06-13: Neoadjuvant paclitaxel/olaparib in comparison to paclitaxel/carboplatinum in patients with HER2-negative breast cancer and homologous recombination deficiency – long-term survival of the GeparOLA study

Background: The GeparOLA study was designed to evaluate the efficacy and safety of the combination of paclitaxel (P) plus olaparib (O) as part of neoadjuvant chemotherapy (NACT) in patients with human epidermal growth factor receptor 2 (HER2)-negative, either hormone receptor (HR)-positive or HR-negative and homologous recombination deficiency (HRD) defined as having a g/tBRCA mutation and/or a high HRD score. Primary analysis showed a pCR rate of 55.1% (90% CI 44.5%-65.3%) with PO and 48.6% (90% CI 34.3%-63.2%) with P plus carboplatinum (Cb). The PO combination could not exclude a pCR rate of ≤55% in the PO arm but was significantly better tolerated. Analysis on the stratified subgroups showed higher pCR rates with PO in the cohorts of patients &lt; 40 years and HR-positive tumors (Fasching Ann Oncol 2020). Here, we report long-term data. Methods: GeparOLA (NCT02789332) was a non-comparative, multicenter, prospective, randomized, open-label, phase II trial. Patients with primary HER2-negative breast cancer, HRD and indication for chemotherapy (cT2-cT4a-d or cT1c and cN+ or cT1c and pNSLN+ or cT1c and TNBC or cT1c and Ki-67 &gt;20%) were randomly assigned to receive either P 80 mg/m2 weekly plus O 100 mg twice daily for 12 weeks or P plus Cb area under the curve 2 (AUC2) weekly for 12 weeks, both followed by four cycles of either 2-weekly or 3-weekly epirubicin 90 mg/m2 plus cyclophosphamide 600 mg/m2. Primary endpoint was pCR (ypT0/is ypN0) rate after NACT with PO followed by EC. Long-term efficacy endpoints included invasive disease-free survival (iDFS), distant disease-free survival (DDFS) and overall survival (OS). The time-to-event endpoints analysis is planned with median follow-up of at least 4 years and a follow-up completeness of at least 80%. Results: Between September 2016 and July 2018, 274 patients were screened, of whom 107 were randomized and 106 (PO N=69; PCb N=37) started treatment. The median age was 47.0 years (range 25.0-71.0); 32 patients were aged &lt; 40 years; 36.2% of patients had cT1 tumors and 31.8% were cN-positive; the majority (86.8%) had grade 3 tumors and a Ki-67&gt;20% (89.6%). Seventy-seven patients (72.6%) had TNBC. After a median follow-up of 49.8 months (range 0.1-69.1), 18 (15 in PO; 3 in PCb) iDFS events and 7 (6 in PO; 1 in PCb) deaths were reported. The 4-year survival rates are shown in the table below. iDFS (HR PO to PCb=2.86 [95%CI 0.83-9.9], log-rank p=0.081), DDFS (HR =3.03 [95%CI 0.67-13.67], log-rank p=0.129), and OS (HR=3.27 [95%CI 0.39-27.2], log-rank p=0.244) tended to be inferior with olaparib. Patients without g/tBRCA mutation seem to benefit from the use of carboplatinum (7/30 iDFS/DDFS events in PO; 0/16 in PCb, log-rank p=0.037, HR n.a.). Conclusions: In patients with HER2-negative and HRD breast cancer the use of olaparib instead of carboplatinum although showing comparable pCR rates, tended to result in an overall inferior outcome. This was mainly driven by the patients without a g/tBRCA mutation. In patients with a g/t BRCA mutation no difference between olaparib and carboplatinum was seen. Key words: Olaparib, HER2-negative breast cancer, HRD, survival Funding: The study was financially supported by AstraZeneca

Citation Format: Peter A. Fasching, Sabine Schmatloch, Jan Hauke, Julia Rey, Christian Jackisch, Peter Klare, Theresa Link, Claus Hanusch, Jens Huober, Andrea Stefek, Sabine Seiler, Wolfgang D. Schmitt, Christoph Uleer, Gabriele Doering, Kerstin Rhiem, Andreas Schneeweiss, Carsten Denkert, Rita K. Schmutzler, Eric Hahnen, Michael Untch, Valentina Nekljudova, Jens-Uwe Blohmer, Sibylle Loibl. Neoadjuvant paclitaxel/olaparib in comparison to paclitaxel/carboplatinum in patients with HER2-negative breast cancer and homologous recombination deficiency – long-term survival of the GeparOLA study [abstract]. In: Proceedings of the 2022 San Antonio Breast Cancer Symposium; 2022 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2023;83(5 Suppl):Abstract nr P4-06-13.

Abstract GS5-02: Neoadjuvant paclitaxel/olaparib in comparison to paclitaxel/carboplatinum in patients with HER2-negative breast cancer and homologous recombination deficiency – long-term survival of the GeparOLA study

Background: The GeparOLA study was designed to evaluate the efficacy and safety of the combination of paclitaxel (P) plus olaparib (O) as part of neoadjuvant chemotherapy (NACT) in patients with human epidermal growth factor receptor 2 (HER2)-negative, either hormone receptor (HR)-positive or HR-negative and homologous recombination deficiency (HRD) defined as having a g/tBRCA mutation and/or a high HRD score. Primary analysis showed a pCR rate of 55.1% (90% CI 44.5%-65.3%) with PO and 48.6% (90% CI 34.3%-63.2%) with P plus carboplatinum (Cb). The PO combination could not exclude a pCR rate of ≤55% in the PO arm but was significantly better tolerated. Analysis on the stratified subgroups showed higher pCR rates with PO in the cohorts of patients &lt; 40 years and HR-positive tumors (Fasching Ann Oncol 2020). Here, we report long-term data. Methods: GeparOLA (NCT02789332) was a non-comparative, multicenter, prospective, randomized, open-label, phase II trial. Patients with primary HER2-negative breast cancer, HRD and indication for chemotherapy (cT2-cT4a-d or cT1c and cN+ or cT1c and pNSLN+ or cT1c and TNBC or cT1c and Ki-67 &gt;20%) were randomly assigned to receive either P 80 mg/m2 weekly plus O 100 mg twice daily for 12 weeks or P plus Cb area under the curve 2 (AUC2) weekly for 12 weeks, both followed by four cycles of either 2-weekly or 3-weekly epirubicin 90 mg/m2 plus cyclophosphamide 600 mg/m2. Primary endpoint was pCR (ypT0/is ypN0) rate after NACT with PO followed by EC. Long-term efficacy endpoints included invasive disease-free survival (iDFS), distant disease-free survival (DDFS) and overall survival (OS). The time-to-event endpoints analysis is planned with median follow-up of at least 4 years and a follow-up completeness of at least 80%. Results: Between September 2016 and July 2018, 274 patients were screened, of whom 107 were randomized and 106 (PO N=69; PCb N=37) started treatment. The median age was 47.0 years (range 25.0-71.0); 32 patients were aged &lt; 40 years; 36.2% of patients had cT1 tumors and 31.8% were cN-positive; the majority (86.8%) had grade 3 tumors and a Ki-67&gt;20% (89.6%). Seventy-seven patients (72.6%) had TNBC. After a median follow-up of 49.8 months (range 0.1-69.1), 18 (15 in PO; 3 in PCb) iDFS events and 7 (6 in PO; 1 in PCb) deaths were reported. The 4-year survival rates are shown in the table below. iDFS (HR PO to PCb=2.86 [95%CI 0.83-9.9], log-rank p=0.081), DDFS (HR =3.03 [95%CI 0.67-13.67], log-rank p=0.129), and OS (HR=3.27 [95%CI 0.39-27.2], log-rank p=0.244) tended to be inferior with olaparib. Patients without g/tBRCA mutation seem to benefit from the use of carboplatinum (7/30 iDFS/DDFS events in PO; 0/16 in PCb, log-rank p=0.037, HR n.a.). Conclusions: In patients with HER2-negative and HRD breast cancer the use of olaparib instead of carboplatinum although showing comparable pCR rates, tended to result in an overall inferior outcome. This was mainly driven by the patients without a g/tBRCA mutation. In patients with a g/t BRCA mutation no difference between olaparib and carboplatinum was seen. Key words: Olaparib, HER2-negative breast cancer, HRD, survival Funding: The study was financially supported by AstraZeneca

Citation Format: Peter A. Fasching, Sabine Schmatloch, Jan Hauke, Julia Rey, Christian Jackisch, Peter Klare, Theresa Link, Claus Hanusch, Jens Huober, Andrea Stefek, Sabine Seiler, Wolfgang D. Schmitt, Christoph Uleer, Gabriele Doering, Kerstin Rhiem, Andreas Schneeweiss, Carsten Denkert, Rita K. Schmutzler, Eric Hahnen, Michael Untch, Valentina Nekljudova, Jens-Uwe Blohmer, Sibylle Loibl. Neoadjuvant paclitaxel/olaparib in comparison to paclitaxel/carboplatinum in patients with HER2-negative breast cancer and homologous recombination deficiency – long-term survival of the GeparOLA study [abstract]. In: Proceedings of the 2022 San Antonio Breast Cancer Symposium; 2022 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2023;83(5 Suppl):Abstract nr GS5-02.

Abstract PD9-04: Immunological and clinical consequences of durvalumab treatment in combination to neoadjuvant chemotherapy in triple-negative breast cancer patients

Background: The implementation of immune checkpoint inhibitors in the therapy of different cancer types has provided promising results, but only a limited number of patients respond. Therefore, biomarkers to identify these responding patients are urgently needed. Methods: The GeparNuevo was a randomized, double-blind phase II trial in which triple-negative breast cancer (TNBC) patients were treated with neoadjuvant chemotherapy (NACT) consisting of nanoparticle albumin-bound paclitaxel in an initial phase followed by treatment with epirubicin and cyclophosphamide. Placebo or durvalumab were given throughout the neo-adjuvant treatment and in the “window” sub-cohort also prior to chemotherapy. Primary objective of this report was to evaluate changes in the blood immune cell repertoires of TNBC patients receiving durvalumab (anti-PD-L1) versus placebo in combination with NACT. At up to 4 different time points during therapy, blood samples were taken and underwent immunomonitoring using multicolor flow cytometry. The absolute counts of the major immune cell subtypes in the blood as well as the frequencies of different immune cell subpopulations and their functional phenotypes along treatment were determined and correlated to clinico-pathologic characteristics of the patients and to treatment response. Results: 120 out of 174 patients included in the GeparNuevo trial underwent blood immunomonitoring; 63 patients belonged to the “window” sub-cohort. Durvalumab administration almost completely blocked the detection of the inhibitory ligand PD-L1 and induced changes in the composition of the immune cell subpopulations. Evaluation of the “window” sub-cohort, in which an enhanced, but not significant pathological clinical response was observed within the immunomonitored patients, identified different markers correlating with clinical response to durvalumab. Higher frequencies of CD4+ T cells at recruitment as well as increased frequencies of T cells bearing the gamma delta TCR along treatment were some of the characteristics of patients responding to durvalumab treatment. Conclusions: The flow cytometry-based immunomonitoring of the clinical trial identified different immune-relevant biomarkers at recruitment as well as during treatment that predict clinical response to durvalumab. After validation of this data in an independent patient cohort, these markers could be implemented for an improved patient stratification to immunotherapy.

Citation Format: Chiara Massa, Thomas Karn, Karsten Weber, Andreas Schneeweiss, Claus Hanusch, Jens-Uwe Blohmer, Dirk-Michael Zahm, Christian Jackisch, Marion van Mackelenbergh, Jörg Thomalla, Frederik Marmé, Jens Huober, Volkmar Müller, Christian Schem, Anja Müller, Elmar Stickeler, Katharina Biehl, Peter A. Fasching, Michael Untch, Sibylle Loibl, Carsten Denkert, Barbara Seliger. Immunological and clinical consequences of durvalumab treatment in combination to neoadjuvant chemotherapy in triple-negative breast cancer patients [abstract]. In: Proceedings of the 2022 San Antonio Breast Cancer Symposium; 2022 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2023;83(5 Suppl):Abstract nr PD9-04.

Neoadjuvant durvalumab improves survival in early triple-negative breast cancer independent of pathological complete response

BACKGROUND

Addition of immune checkpoint inhibitors (CPI) to neoadjuvant chemotherapy (NACT) is a promising strategy in early breast cancer, but the optimal duration of therapy is currently unknown. In the GeparNuevo (NCT02685059) trial, addition of durvalumab to NACT as previously reported led to a moderate increase in pCR rate by absolute 9% (p=0.287).

PATIENTS AND METHODS

Durvalumab or placebo 1.5g/placebo q4 weeks plus nab-paclitaxel 125mg/m² weekly for 12 weeks, followed by 4 cycles durvalumab/placebo plus epirubicin/cyclophosphamide (EC) q2 weeks was given to cT1b-cT4a-d TNBC patients. Durvalumab was not continued after surgery. Primary objective was pathological complete response (pCR). Secondary endpoints included invasive disease-free survival (iDFS), distant disease-free survival (DDFS) and overall survival (OS).

RESULTS

174 patients were randomised between June 2016 and October 2017. After a median follow-up of 43.7 months, 34 events had occurred. Despite a non-significant increase in the pCR rate, significant differences were observed for 3-year iDFS, DDFS and OS: iDFS was 85.6% with durvalumab vs 77.2% with placebo (HR 0.48, 95%CI 0.24-0.97, stratified log-rank p=0.036); DDFS 91.7% vs 78.4% (HR 0.31, 95%CI 0.13-0.74, p=0.005); OS 95.2% vs 83.5% (HR 0.24, 95%CI 0.08-0.72, p=0.006). pCR patients had 3-year iDFS of 95.5% with durvalumab and 86.1% without (HR 0.22, 95% CI 0.05-1.06). In non-pCR cohort 3-year iDFS was 76.3% vs 69.7% (HR 0.67, 95% CI 0.29-1.54). Multivariable analysis confirmed durvalumab effect independent of the pCR effect. No new safety signals occurred.

CONCLUSION

Durvalumab added to NACT in TNBC significantly improved survival despite a modest pCR increase and no adjuvant component of durvalumab. Additional studies are needed to clarify the optimal duration and sequence of CPIs in the treatment of early TNBC.

Low TMB as predictor for additional benefit from neoadjuvant immune checkpoint inhibition in triple-negative breast cancer

581

Background: It is commonly anticipated that a high tumor mutational burden (TMB) is a predictor of response to immune checkpoint blockade (ICB). We previously showed that triple-negative breast cancer (TNBC) from the GeparNuevo study with high TMB displayed increased response both to neoadjuvant chemo-ICB with durvalumab but also to chemotherapy alone, with no significant interaction with treatment arm (Karn et al. Ann Oncol 2020). In contrast, we also observed that cases with very low TMB more often displayed a pCR after treatment with chemo-ICB than with chemotherapy alone. This may in fact suggest a benefit of ICB to those TNBC with rather low TMB. Methods: We have analyzed the distant disease-free survival (DDFS) of GeparNuevo patients according to TMB and treatment arm (neoadjuvant chemotherapy plus durvalumab or chemotherapy plus placebo). For TMB (mut/Mb) we applied the identical cutoff of the upper tertile as in our previous analysis. Results: The median follow-up of the time-to-event data was 43.7 months. Data of TMB was available in 149 of 174 patients. We found that within the high-TMB tumors (durvalumab: n=27; placebo: n=23), DDFS was similar between both arms of the trial (durvalumab vs. placebo: HR (hazard ratio) 0.95 [95%CI 0.19-4.69], p=0.95). Strikingly however, within the low-TMB group (durvalumab: n=47; placebo: n=52) we observed a significantly better DDFS in the durvalumab-chemotherapy combination arm, in contrast to the arm treated only with chemotherapy (durvalumab vs. placebo: HR 0.23 [95%CI 0.06-0.79], p=0.02; interaction test for TMB and treatment arm p=0.17). The observation was also robust to alternative TMB cutoffs. Similar results were obtained for invasive disease-free survival. Conclusions: Our results show, in contrast to other published data, that patients with early TNBC and low TMB/neoantigen counts may benefit from short-term neoadjuvant durvalumab treatment, while for those with high TMB, durvalumab plus chemotherapy does not improve efficacy over chemotherapy alone.

Biomarkers for response to immunotherapy in triple-negative breast cancer: Differences between survival and pCR biomarkers

583

Background: Immunotherapy is entering clinical practice as a promising new neoadjuvant therapeutic approach in triple-negative breast cancer, and it is important to identify biomarkers to focus this therapy on those patients that have the highest benefit. Interestingly, an improved survival outcome is observed in pCR and non-pCR patients, which raises the hypothesis that biomarkers might also be different for pCR prediction as well as prognosis. In this study, we investigated this hypothesis in the neoadjuvant GeparNuevo trial. Methods: A total of 174 patients were randomized to receive neoadjuvant chemotherapy with durvalumab vs. placebo. HTG EdgeSeq mRNA analysis was performed for a total of 2549 genes in 162 pretherapeutic core biopsies. In addition, tumor-infiltrating lymphocytes (stromal and intratumoural) as well as PD-L1 protein expression was evaluated by IHC. We systematically compared the distant disease-free survival (DDFS) of 5 predefined gene signatures (including the GeparSixto immune signature) as well as 12 single mRNA markers identified in previous projects between treatment arms using univariate Cox proportional-hazard regression analyses. In addition, exploratory biomarker analyses were performed. Results: The PSIP1 gene expression (per 1 unit hazard ratio [HR]: 0.58 95%CI 0.41-0.83; p=0.002), TAP1 (per 1 unit HR: 0.68 95%CI 0.48-0.95; p=0.025) as well as stromal TILs (sTILs) (per 10% HR: 0.73 95%CI 0.56-0.95; p=0.019) were significant for improved DDFS in the complete cohort. In the placebo arm PSIP1 (HR 0.50 95%CI 0.29-0.87; p=0.014) as well as sTILs (HR 0.73 95%CI 0.53-0.99; p=0.044) were significant for improved DDFS. In the durvalumab arm, the gene expression of PSIP1 (HR 0.54 95%CI 0.31-0.94; p=0.029), PD-L1/CD274 (per 1 unit HR: 0.41 95%CI 0.21-0.77; p=0.006), CD38 (per 1 unit: HR 0.52 95%CI 0.29-0.92; p=0.026) as well as the GeparSixto immune signature (per 1 unit HR: 0.51 95%CI 0.27-0.97; p=0.041) were significant for improved DDFS, with a positive test for interaction with treatment arm for PD-L1/CD274 (interaction p=0.020). Additional analyses, including multivariate Cox regressions for DDFS as well as systematic comparisons for biomarkers for DDFS and for pCR, will be presented. Conclusions: Our analysis suggests that biomarkers for immune response are linked to improved survival with neoadjuvant durvalumab therapy and that in this setting, survival biomarkers are not identical to pCR biomarkers. The results are a basis for a further dissection of the contribution of pCR to survival effects of immunotherapy.

Effect of Denosumab Added to 2 Different nab-Paclitaxel Regimens as Neoadjuvant Therapy in Patients With Primary Breast Cancer: The GeparX 2 × 2 Randomized Clinical Trial

Importance

Adjuvant denosumab might improve disease-free survival in hormone receptor (HR)-positive primary breast cancer (BC). The optimal neoadjuvant nab-paclitaxel schedule in terms of efficacy and safety is unclear.

Objective

To determine whether adding denosumab to anthracycline/taxane-containing neoadjuvant chemotherapy (NACT) increases the pathological complete response (pCR) rate and which nab-paclitaxel schedule is more effective in the NACT setting.

Design, Setting, and Participants

The GeparX was a multicenter, prospective, open-label, phase 2b, 2 × 2 randomized clinical trial conducted by GBG and AGO-B at 38 German sites between February 2017 and March 2019. The analysis data set was locked September 4, 2020; analysis was completed November 13, 2020. Patients had unilateral or bilateral primary BC, stage cT2-cT4a-d or cT1c, with either clinically node-positive or pathologically node-positive or HR-negative disease, or Ki-67 proliferation index greater than 20%, or ERBB2 (formerly HER2)-positive BC.

Interventions

Patients were randomized to receive or not receive denosumab, 120 mg subcutaneously every 4 weeks for 6 cycles, and either nab-paclitaxel, 125 mg/m2 weekly for 12 weeks or days 1 and 8 every 3 weeks for 4 cycles (8 doses), followed by 4 cycles of epirubicin/cyclophosphamide, 90/600 mg/m2 (every 2 weeks or every 3 weeks). Carboplatin was given in triple-negative BC (TNBC), and trastuzumab biosimilar ABP980 plus pertuzumab was given in ERBB2-positive BC (ERBB2-positive substudy).

Main Outcomes and Measures

The primary outcome was pCR rates between arms for each randomization.

Results

A total of 780 female (n = 779) and male (n = 1) patients (median [range] age, 49.0 [22-80] years) were randomized to the 4 treatment groups. The pCR (ypT0 ypN0) rate was 41.0% (90% CI, 37%-45%) with denosumab vs 42.8% (90% CI, 39%-47%) (P = .58) without denosumab, irrespective of BC subtype. Nab-paclitaxel weekly resulted in a significantly (significance level of α = .10) higher pCR rate of 44.9% (90% CI, 41%-49%) vs 39.0% (90% CI, 35%-43%) (P = .06) with nab-paclitaxel days 1 and 8 every 3 weeks. The pCR rates for nab-paclitaxel schedules in subgroups were only significantly different for TNBC (60.4% vs 50.0%; P = .06). Grade 3 to 4 toxic effects did not differ with or without denosumab. Nonhematologic toxic effects of grade 3 to 4 were higher with nab-paclitaxel weekly (33.7% vs 24.1%; P = .004).

Conclusions and Relevance

In this randomized clinical trial, denosumab added to anthracycline/taxane-based NACT did not improve pCR rates. Nab-paclitaxel at a dosage of 125 mg/m2 weekly significantly increased the pCR rate compared with the days 1 and 8, every-3-weeks schedule overall and in TNBC, but generated higher toxicity.

Trial Registration

ClinicalTrials.gov Identifier: NCT02682693.

Quality of Life Effects of an Oral Fixed Combination of Netupitant and Palonosetron in Chemotherapy-Induced Nausea and Vomiting Prevention: Real-World Evidence in Patients with Breast Cancer Receiving Anthracycline-Cyclophosphamide-Based Chemotherapy

INTRODUCTION

In a prospective non-interventional study involving 2,173 patients, we showed that use of the oral fixed combination of netupitant 300 mg and palonosetron 0.5 mg (NEPA) for prevention of chemotherapy (Ctx)-induced nausea and vomiting has beneficial effects on the quality of life (QoL) of patients with various types of cancers receiving highly or moderately emetogenic Ctx. Here, we report on the effects on QoL, effectiveness, and tolerability of NEPA in patients with breast cancer exposed to anthracycline-cyclophosphamide (AC)-based Ctx.

METHODS

This is a post hoc subanalysis of a prospective non-interventional study in 1,197 patients with breast cancer receiving up to 3 cycles of doxorubicin or epirubicin plus cyclophosphamide and NEPA. NEPA administration was per the summary of product characteristics.

RESULTS

In cycle 1 of Ctx, a large proportion of patients (84%) reported "no impact on daily life" (NIDL) due to vomiting; 53% of patients reported NIDL due to nausea. The complete response rate was 86/88/81% in the acute/delayed/overall phase in cycle 1, and NEPA was well tolerated throughout the study.

CONCLUSION

The real-world beneficial effects of NEPA prophylaxis on QoL were confirmed for patients with breast cancer receiving AC. NEPA was effective with a good safety profile in this patient population in clinical practice.

Pathological Response in the Breast and Axillary Lymph Nodes after Neoadjuvant Systemic Treatment in Patients with Initially Node-Positive Breast Cancer Correlates with Disease Free Survival: An Exploratory Analysis of the GeparOcto Trial

Simple Summary

The extent of axillary surgery has been reduced in recent years to minimize side effects. However, a negative impact of reduced surgery on outcome must be avoided. We investigated for whom the extent of surgery can be safely reduced by examining early-stage breast cancer patients converting from lymph node (LN)-positive to LN-negative disease after neoadjuvant systemic treatment (NAST). Of 242 initially LN-positive patients treated within the GeparOcto trial, 54.5% were classified as LN-negative after NAST, 31.8% as LN-positive, and for 13.6% data were missing. Overall, 92.1% of patients underwent complete axillary LN dissection, with 6.6% undergoing sentinel LN dissection only. At surgery, 55.4% of patients had no signs of cancer in the LN, 45.0% had no signs of cancer in the breast (of those 8.3% had involved LN), and 41.3% had no signs of cancer at all. Patients with involved LN still had a bad prognosis. Conversion from LN-positive to LN-negative after NAST is of highest prognostic value. Surgical axillary staging after NAST is essential in these patients to offer tailored treatment.

Abstract

Background: The conversion of initially histologically confirmed axillary lymph node-positive (pN+) to ypN0 after neoadjuvant systemic treatment (NAST) is an important prognostic factor in breast cancer (BC) patients and may influence surgical de-escalation strategies. We aimed to determine pCR rates in lymph nodes (pCR-LN), the breast (pCR-B), and both (tpCR) in women who present with pN+ BC, to assess predictors for response and the impact of pCR-LN, pCR-B, and tpCR on invasive disease-free survival (iDFS). Methods: Retrospective, exploratory analysis of 242 patients with pN+ at diagnosis from the multicentric, randomized GeparOcto trial. Results: Of 242 patients with initially pN+ disease, 134 (55.4%) had a pCR-LN, and 109 (45.0%) a pCR-B. Of the 109 pCR-B patients, 9 (8.3%) patients had involved LN, and 100 (41.3%) patients had tpCR. Those with involved LN still had a bad prognosis. As expected, pCR-B and intrinsic subtypes (TNBC and HER2+) were identified as independent predictors of pCR-LN. pCR-LN (ypN0; hazard ratio 0.42; 95%, CI 0.23–0.75; p = 0.0028 for iDFS) was the strongest independent prognostic factor. Conclusions: In initially pN+ patients undergoing NAST, the conversion to ypN0 is of high prognostic value. Surgical axillary staging after NAST is still essential in these patients to offer tailored treatment.

Validation of the 21-Gene Recurrence Score Assay in Patients with Hormone Receptor-Positive, HER2-Negative Breast Cancer and 0 to 3 Positive Lymph Nodes – Risk Pattern and Outcomes on a Community Level

Introduction The aim of the present study was to analyze the performance of Oncotype DX® multigene assay (ODX) in patients with 0-3 lymph nodes in a high volume community hospital. Methods Patients with non-metastatic HR+/HER2- EBC and 0-3 positive lymph nodes, who underwent primary surgery at the Red Cross Hospital Munich, Germany and consecutively had ODX testing were included in this retrospective study. The distribution of clinico-pathologic characteristics, recurrence score (RS) risk and use of systemic therapy were compared among patients without positive lymph nodes (N0) and patients with micrometastases or 1 to 3 positive lymph nodes (N1). Disease free survival (DFS) and overall survival (OS) were estimated. Results From 2012 to2017 ODX was consecutively performed in 575 (16.4%) of 3492 women with HR+/ HER- EBC, of which 553 were eligible for this analysis (N0: 60.8%; N1: 39.2%). Among the patients included, 441 (79.7%) had a RS of 0 to 25 and 112 (20.3%) had a RS of 26 or higher. In patients with RS 0 to 25 the rate of chemotherapy use was low, independent from nodal status (N0: 17.1% and N1: 19.1%) and 5y-DFS was 90.5% and 91.7% for N0 and N1 patients, respectively. There was no significant difference in DFS (90.5% vs. 93.3%; p= 0.101) or OS (97.2% vs. 96.0%; p= 0.737) for patients with a RS 0 to 25 when treated with chemo-endocrine therapy or endocrine therapy alone, independent from nodal status. Conclusions The results of the study confirm the observations from randomized studies on the use of the ODX in a real world population in terms of risk distribution and patient outcome. Adjuvant chemotherapy could be safely omitted in patients with HR+/HER2- breast cancer with 0-3 positive lymph nodes and RS<25.

Survival analysis of the randomised phase III GeparOcto trial comparing neoadjuvant chemotherapy of intense dose-dense epirubicin, paclitaxel, cyclophosphamide versus weekly paclitaxel, liposomal doxorubicin (plus carboplatin in triple-negative breast cancer) for patients with high-risk early breast cancer

BACKGROUND

GeparOcto demonstrated that pathological complete response (pCR) of intense dose-dense epirubicin, paclitaxel and cyclophosphamide (iddEPC) was comparable to weekly paclitaxel/non-pegylated liposomal doxorubicin (plus carboplatin (PM(Cb) in triple-negative breast cancer [TNBC]) in high-risk early breast cancer (BC). Here, we report time-to-event secondary end-points.

PATIENTS AND METHODS

Patients were randomised to receive 18 weeks of E (150 mg/m²) followed by P (225 mg/m²) followed by C (2000 mg/m²), each q2w or weekly P (80 mg/m²) plus M (20 mg/m²) plus, in TNBC, Cb (AUC 1.5). Patients with human epidermal growth factor receptor 2-positive (HER2+)BC received trastuzumab (6[loading dose 8]mg/kg q3w) and pertuzumab (420[840]mg q3w) with P and C cycles.

RESULTS

945 patients started treatment (iddEPC n = 470; PM(Cb) n = 475). After a median follow-up of 47.0 (range 1.6-61.5) months, 162 (75 in iddEPC; 87 in PM(Cb)) invasive disease-free survival (iDFS) events and 79 (41 in iddEPC; 38 in PM(Cb)) deaths were reported. No significant difference was observed in 4-year iDFS (81.9% iddEPC versus 79.7% PM(Cb), HR = 1.16 [95%CI 0.85-1.59], log-rank p = 0.334) or 4-year overall survival (OS) (90.3% iddEPC versus 90.6% PM(Cb), HR = 0.90 [95%CI 0.58-1.40], log-rank p = 0.637) overall and in HER2+ and TNBC subgroups. HR+/HER2- BC patients, however, had significantly better 4-year iDFS (77.9% iddEPC versus 62.5% PM, HR = 2.11 [95%CI 1.08-4.10], log-rank p = 0.025) and 4-year OS with iddEPC (94.7% iddEPC versus 80.1% PM, HR = 3.26 [95%CI 1.06-10.00], log-rank p = 0.029).

CONCLUSION

While there was no difference in survival for the entire cohort, the HR+/HER2-subgroup significantly benefits from iddEPC. This supports the concept of an additional effect of NACT beyond pCR in patients with HR+/HER2- BC. CLINICALTRIALS.

GOV IDENTIFIER

NCT02125344.

Clinical and molecular characteristics of HER2-low-positive breast cancer: pooled analysis of individual patient data from four prospective, neoadjuvant clinical trials

BACKGROUND

The development of anti-HER2 antibody-drug conjugates opens new therapeutic options for patients with breast cancer, including patients with low expression of HER2. To characterise this new breast cancer subtype, we have compared the clinical and molecular characteristics of HER2-low-positive and HER2-zero breast cancer, including response to neoadjuvant chemotherapy and prognosis.

METHODS

In this pooled analysis of individual patient data, we evaluated a cohort of 2310 patients with HER2-non-amplified primary breast cancer that were treated with neoadjuvant combination chemotherapy in four prospective neoadjuvant clinical trials (GeparSepto, NCT01583426; GeparOcto, NCT02125344; GeparX, NCT02682693; Gain-2 neoadjuvant, NCT01690702) between July 30, 2012, and March 20, 2019. Central HER2 testing was done prospectively before random assignment of participants in all trials. HER2-low-positive status was defined as immunohistochemistry (IHC) 1+ or IHC2+/in-situ hybridisation negative and HER2-zero was defined as IHC0, based on the American Society of Clinical Oncology/College of American Pathologists guidelines. Disease-free survival and overall survival data were available for 1694 patients (from all trials except GeparX) with a median follow-up of 46·6 months (IQR 35·0-52·3). Bivariable and multivariable logistic regression models and Cox-proportional hazards models were performed based on a predefined statistical analysis plan for analysis of the endpoints pathological complete response, disease-free survival, and overall survival.

FINDINGS

A total of 1098 (47·5%) of 2310 tumours were HER2-low-positive and 1212 (52·5%) were HER2-zero. 703 (64·0%) of 1098 patients with HER2-low-positive tumours were hormone receptor positive, compared with 445 (36·7%) of 1212 patients with HER2-zero tumours (p<0.0001). HER2-low-positive tumours had a significantly lower pathological complete response rate than HER2-zero tumours (321 [29·2%] of 1098 vs 473 [39·0%] of 1212, p=0·0002). Pathological complete response was also significantly lower in HER2-low-positive tumours versus HER2-zero tumours in the hormone receptor-positive subgroup (123 [17·5%] of 703 vs 105 [23·6%] of 445, p=0·024), but not in the hormone receptor-negative subgroup (198 [50·1%] of 395 vs 368 [48·0%] of 767, p=0·21). Patients with HER2-low-positive tumours had significantly longer survival than did patients with HER2-zero tumours (3-year disease-free survival: 83·4% [95% CI 80·5-85·9] vs 76·1% [72·9-79·0]; stratified log-rank test p=0·0084; 3-year overall survival: 91·6% [84·9-93·4] vs 85·8% [83·0-88·1]; stratified log-rank test p=0·0016). Survival differences were also seen in patients with hormone receptor-negative tumours (3-year disease-free survival: 84·5% [95% CI 79·5-88·3] vs 74·4% [70·2-78.0]; stratified log-rank test p=0·0076; 3-year overall survival: 90·2% [86·0-93·2] vs 84·3% [80·7-87·3], stratified log-rank test p=0·016), but not in patients with hormone receptor-positive tumours (3-year disease-free survival 82·8% [79·1-85·9] vs 79·3% [73·9-83·7]; stratified log-rank test p=0·39; 3-year overall survival 92·3% [89·6-94·4] vs 88·4% [83·8-91·8]; stratified log-rank test p=0·13).

INTERPRETATION

Our results show that HER2-low-positive tumours can be identified as new subgroup of breast cancer by standardised IHC, distinct from HER2-zero tumours. HER2-low-positive tumours have a specific biology and show differences in response to therapy and prognosis, which is particularly relevant in therapy-resistant, hormone receptor-negative tumours. Our results provide a basis for a better understanding of the biology of breast cancer subtypes and the refinement of future diagnostic and therapeutic strategies.

FUNDING

German Cancer Aid (Deutsche Krebshilfe).

Utility of the CPS + EG scoring system in triple-negative breast cancer treated with neoadjuvant chemotherapy

BACKGROUND

Pathological complete response (pCR) after neoadjuvant chemotherapy (NACT) is associated with superior survival. This association is strongest in triple-negative breast cancer (TNBC). The CPS + EG system, based on pre-treatment clinical (CS) and post-treatment pathological stage (PS), oestrogen-receptor status (E) and grade (G), leads to a refined estimate of prognosis after NACT in all-comers and hormone receptor-positive/human epidermal growth factor receptor 2 (HER2)-negative breast cancer. Here, we investigate if CPS + EG scoring provides a superior estimate of prognosis in TNBC to select patients for postneoadjuvant therapy.

METHODS

We calculated the CPS + EG score for 1795 patients with TNBC from 8 prospective German trials. Five-year disease-free survival (DFS) and overall survival estimates were calculated using the Kaplan-Meier method.

RESULTS

In TNBC, patients with pCR (ypT0/is ypN0, n = 822, 45.8%) had a 5-year DFS of 86%, whereas patients with residual American Joint Committee on Cancer stage I disease (n = 383; 21.3%) had a 5-year DFS of 77.5%.CPS + EG led to superior prognostic information compared with that provided by the clinical stage, but it was inferior to the prognostic information provided by the pathological stage (c-index statistics, p < 0.001). CPS + EG did not discriminate prognosis within the two best prognostic groups (score 1 and 2; n = 362; 37.2%). In contrast, pCR status added prognostic information beyond CPS + EG. Patients with a CPS + EG score of 3 had a 5-year DFS rate of 64% overall, but those with pCR had a 5-year DFS rate of 84%, and those without pCR had a 5-year DFS rate of only 49.7%.

CONCLUSIONS

In TNBC, CPS + EG scoring provided inferior prognostic information compared with the pathological stage and was unable to identify patients without pCR and with a sufficiently good prognosis, who could avoid postneoadjuvant therapy. pCR remains the strongest and most clinically useful prognostic factor after NACT. Other biologic factors beyond pCR are needed in TNBC.

Durvalumab improves long-term outcome in TNBC: results from the phase II randomized GeparNUEVO study investigating neodjuvant durvalumab in addition to an anthracycline/taxane based neoadjuvant chemotherapy in early triple-negative breast cancer (TNBC)

506

Background: The GeparNuevo trial investigated the addition of durvalumab, an anti-PD-L1 checkpoint inhibitor (CPI), to standard neoadjuvant chemotherapy (NACT) in patients with early TNBC. Durvalumab increased the pathological complete response (pCR) rate particularly in patients treated with durvalumab alone before start of chemotherapy (Loibl et al. Ann Oncol 2019). Methods: GeparNuevo randomized patients with cT1b-cT4a-d tumors and centrally confirmed TNBC to durvalumab (D) 1.5 g i.v. or placebo every 4 weeks. D/placebo monotherapy (0.75 g i.v.) was given for the first 2 weeks (window phase), followed by D/placebo plus nab-paclitaxel 125 mg/m² weekly for 12 weeks, followed by D/placebo plus epirubicin/cyclophosphamide (EC) q2 weeks for 4 cycles. Randomization was stratified by stromal tumor infiltrating lymphocytes (sTILs) (low (≤10%), intermediate (11-59%), high (≥60%)). The primary objective was pCR (ypT0 ypN0). Secondary time-to-event endpoints included invasive disease-free survival (iDFS), distant disease-free survival (DDFS) and overall survival (OS). Results: A total of 174 patients were enrolled between June 2016 and September 2017. The pCR rate with durvalumab was 53.4% versus placebo 44.2% (OR 1.45, 95% CI 0.80–2.63, unadjusted Wald p = 0.224). Durvalumab effect was seen only in the window cohort (pCR 61.0% versus 41.4%, OR 2.22, 95% CI 1.06–4.64, p = 0.035; interaction p = 0.048). After a median follow-up of 42.2 months, 34 events occurred in 174 patients. 3-year iDFS in pCR vs non pCR was 92.0% vs 71.9% (log-rank p = 0.002). 3-year iDFS was 84.9% with durvalumab vs 76.9% with placebo (HR 0.54, 95%CI 0.27-1.09, stratified log-rank p = 0.0559); 3-year DDFS 91.4% vs 79.5% (HR 0.37, 95%CI 0.15-0.87, p = 0.0148); 3-year OS 95.1% vs 83.1% (HR 0.26, 95%CI 0.09-0.79, p = 0.0076). No difference was seen in iDFS, DDFS and OS between the window and no window cohort. Conclusions: Durvalumab added to neoadjuvant chemotherapy in TNBC significantly improved long-term outcome despite a small pCR increase and no continuation after surgery. It needs to be questioned whether adjuvant therapy with CPI is needed at all. Clinical trial information: NCT02685059.

Therapy response and prognosis of patients with early breast cancer with low positivity for hormone receptors - An analysis of 2765 patients from neoadjuvant clinical trials

AIM

To evaluate HER2-negative breast cancer (BC) with a low hormone receptor (HR) expression, with regard to pathological complete response (pCR) and survival, in comparison to triple-negative BC (TNBC) and strong HR-positive BC.

METHODS

We compared negative [oestrogen (ER) and progesterone receptor (PR) <1%], low-positive (ER and/or PR 1-9%) and strong-positive (ER or PR 10-100%) HR-expression in neoadjuvant clinical trial cohorts (n = 2765) of BC patients. End-points were disease-free survival (DFS), distant-disease free survival (DDFS) and overall survival (OS). We performed RNA sequencing on available tumour tissue samples from patients with low-HR expression (n = 38).

RESULTS

Ninety-four (3.4%) patients had low HR-positive tumours, 1769 (64.0%) had strong HR-positive tumours, and 902 (32.6%) had TNBC. There were no significant differences in pCR rates between women with low HR-positive tumours (27.7%) and women with TNBC (35.5%). DFS and DDFS were also not different [for DFS, hazard ratio 1.26, 95%-CI (confidence interval) : 0.87-1.83, log-rank test p = 0.951; for DDFS, hazard ratio 1.17, 95%-CI: 0.78-1.76, log-rank test p = 0.774]. Patients with strong HR-positive tumours had a significantly lower pCR rate (pCR 9.4%; odds ratio 0.38, 95%-CI: 0.23-0.63), but better DFS (hazard ratio 0.48, 95%-CI: 0.33-0.70) and DDFS (hazard ratio 0.49, 95%-CI: 0.33-0.74) than patients with low HR-positive tumours. Molecular subtyping (RNA sequencing) of low HR-positive tumours classified these predominantly into a basal subtype (86.8%).

CONCLUSION

Low HR-positive, HER2-negative tumours have a similar clinical behaviour to TNBC showing high pCR rates and poor survival and also a basal-like gene expression signature. Patients with low HR-positive tumours should be regarded as candidates for therapy strategies targeting TNBC.

Association of Germline Variant Status With Therapy Response in High-risk Early-Stage Breast Cancer: A Secondary Analysis of the GeparOcto Randomized Clinical Trial

Importance

The GeparOcto randomized clinical trial compared the efficacy of 2 neoadjuvant breast cancer (BC) treatment regimens: sequential intense dose-dense epirubicin, paclitaxel, and cyclophosphamide (iddEPC) vs weekly paclitaxel and nonpegylated liposomal doxorubicin (PM) in patients with different biological BC subtypes. Patients with triple-negative BC (TNBC) randomized to the PM arm received additional carboplatin (PMCb). Overall, no difference in pathologic complete response (pCR) rates was observed between study arms. It remained elusive whether the germline variant status of BRCA1/2 and further BC predisposition genes are associated with treatment outcome.

Objective

To determine treatment outcome for BC according to germline variant status.

Design, Setting, and Participants

This retrospective biomarker study is a secondary analysis of the GeparOcto multicenter prospective randomized clinical trial conducted between December 2014 and June 2016. Genetic analyses assessing for variants in BRCA1/2 and 16 other BC predisposition genes in 914 of 945 women were performed at the Center for Familial Breast and Ovarian Cancer, Cologne, Germany, from August 2017 through December 2018.

Main Outcomes and Measures

Proportion of patients who achieved pCR (ypT0/is ypN0 definition) after neoadjuvant treatment according to germline variant status.

Results

In the study sample of 914 women with different BC subtypes with a mean (range) age at BC diagnosis of 48 (21-76) years, overall higher pCR rates were observed in patients with BRCA1/2 variants than in patients without (60.4% vs 46.7%; odds ratio [OR], 1.74; 95% CI, 1.13-2.68; P = .01); variants in non-BRCA1/2 BC predisposition genes were not associated with therapy response. Patients with TNBC with BRCA1/2 variants achieved highest pCR rates. In the TNBC subgroup, a positive BRCA1/2 variant status was associated with therapy response in both the PMCb arm (74.3% vs 47.0% without BRCA1/2 variant; OR, 3.26; 95% CI, 1.44-7.39; P = .005) and the iddEPC arm (64.7% vs 45.0%; OR, 2.24; 95% CI, 1.04-4.84; P = .04). A positive BRCA1/2 variant status was also associated with elevated pCR rates in patients with ERBB2-negative, hormone receptor-positive BC (31.8% vs 11.9%; OR, 3.44; 95% CI, 1.22-9.72; P = .02).

Conclusions and Relevance

Effective chemotherapy for BRCA1/2-mutated TNBC is commonly suggested to be platinum based. With a pCR rate of 64.7%, iddEPC may also be effective in these patients, though further prospective studies are needed. The elevated pCR rate in BRCA1/2-mutated ERBB2-negative, hormone receptor-positive BC suggests that germline BRCA1/2 testing should be considered prior to treatment start.

Trial Registration

ClinicalTrials.gov Identifier: NCT02125344.

Differential effect on different immune subsets of neoadjuvant chemotherapy in patients with TNBC

Background

Triple-negative breast cancer (TNBC) is the most aggressive form of breast cancer (BC). Due to the absence of targets such as HER2 or hormone receptors, early TNBC is treated with surgery and chemotherapy. Since TNBC is also considered the most immunogenic type of BC with tumor infiltrating lymphocytes that are predictive for chemotherapy response and prognostic for patients′ survival, many different immunotherapeutic strategies are currently explored in clinical trials for the treatment of this disease. In order to efficiently combine chemotherapy with immunotherapy, it is important to evaluate the effect of chemotherapy on immune cells in vivo.

Methods

Peripheral blood was taken from 56 patients with TNBC undergoing neoadjuvant chemotherapy with nanoparticle albumin-bound paclitaxel (Nab-Pac) followed by epirubicin and cyclophosphamide (EC) at three different time points. Multicolor flow cytometry was used to characterize the immune cell composition and functional properties along neoadjuvant chemotherapy.

Results

Whereas the first phase of the neoadjuvant chemotherapy did not significantly alter the patients′ immune cell composition, after the second phase of chemotherapeutic administration most B cells (>90%) were lost and the frequency of natural killer (NK) cells and CD4⁺ T lymphocytes decreased approximately to 50%. In contrast, the frequency of CD8⁺ T cells were less affected.

Conclusions

Despite late consequences of Nab-Pac cannot be ruled out, these data suggest that different chemotherapeutics might have distinct effects on the immune cell repertoire and that different immune cell populations exhibit a specific susceptibility to these chemotherapies with B and NK cells being more affected than T cells. This might also have an impact on the combination of chemotherapies with immunotherapies.

Trial registration number

NCT02685059.

Neoadjuvant paclitaxel/olaparib in comparison to paclitaxel/carboplatinum in patients with HER2-negative breast cancer and homologous recombination deficiency (GeparOLA study)

BACKGROUND

The efficacy and toxicity of olaparib as combination therapy in early breast cancer (BC) patients with homologous recombinant deficiency (HRD) [score high and/or germline (g) or tumour (t) BRCA1/2 mutation] is not well described. GeparOLA (ClinicalTrials.gov, NCT02789332) investigated olaparib in combination with paclitaxel in HER2-negative early BC with HRD.

PATIENTS AND METHODS

Patients with untreated primary HER2-negative cT2-cT4a-d or cT1c with either cN+ or pNSLN+ or cT1c and triple-negative breast cancer (TNBC) or cT1c and Ki-67>20% BC with HRD were randomised either to paclitaxel (P) 80 mg/m² weekly plus olaparib (O) 100 mg twice daily for 12 weeks or P plus carboplatinum (Cb) area under the curve 2 weekly for 12 weeks, both followed by epirubicin/cyclophosphamide (EC). Stratification factors were hormone receptor (HR) status (HR+ versus HR-) and age (<40 versus ≥40 years). The primary endpoint was pathological complete response (pCR; ypT0/is ypN0). A two-sided one-group χ²-test was planned to exclude a pCR rate of ≤55% in the PO-EC arm. Secondary end points were other pCR definitions, breast conservation rate, clinical/imaging response, tolerability and safety.

RESULTS

A total of 107 patients were randomised between September 2016 and July 2018; 106 (PO N = 69; PCb N = 37) started treatment. Median age was 47.0 years (range 25.0-71.0); 36.2% had cT1, 61.0% cT2, 2.9% cT3, and 31.8% cN-positive tumours; grade 3 tumours: 86.8%; Ki-67>20%: 89.6%; TNBC: 72.6%; confirmed gBRCA1/2 mutation: 56.2%. The pCR rate with PO was 55.1% [90% confidence interval (CI) 44.5% to 65.3%] versus PCb 48.6% (90% CI 34.3% to 63.2%). Analysis for the stratified subgroups showed higher pCR rates with PO in the cohorts of patients <40 years and HR+ patients.

CONCLUSION

GeparOLA could not exclude a pCR rate of ≤55% in the PO arm. PO was significantly better tolerated and the combination merits further evaluation.

A randomised phase II study investigating durvalumab in addition to an anthracycline taxane-based neoadjuvant therapy in early triple-negative breast cancer: clinical results and biomarker analysis of GeparNuevo study

BACKGROUND

Combining immune-checkpoint inhibitors with chemotherapy yielded an increased response rates in patients with metastatic triple-negative breast cancer (TNBC). Therefore, we evaluated the addition of durvalumab to standard neoadjuvant chemotherapy (NACT) in primary TNBC.

PATIENTS AND METHODS

GeparNuevo is a randomised phase II double-blind placebo-controlled study randomising patients with TNBC to durvalumab or placebo given every 4 weeks in addition to nab-paclitaxel followed by standard EC. In the window-phase durvalumab/placebo alone was given 2 weeks before start of nab-paclitaxel. Randomisation was stratified by stromal tumour-infiltrating lymphocyte (sTILs). Patients with primary cT1b-cT4a-d disease, centrally confirmed TNBC and sTILs were included. Primary objective was pathological complete response (pCR) (ypT0 ypN0).

RESULTS

A total of 174 patients were randomised, 117 participated in the window-phase. Median age was 49.5 years (range 23-76); 47 patients (27%) were younger than 40 years; 113 (65%) had stage ≥IIA disease, 25 (14%) high sTILs, 138 of 158 (87%) were PD-L1-positive. pCR rate with durvalumab was 53.4% (95% CI 42.5% to 61.4%) versus placebo 44.2% (95% CI 33.5% to 55.3%; unadjusted continuity corrected χ2P = 0.287), corresponding to OR = 1.45 (95% CI 0.80-2.63, unadjusted Wald P = 0.224). Durvalumab effect was seen only in the window cohort (pCR 61.0% versus 41.4%, OR = 2.22, 95% CI 1.06-4.64, P = 0.035; interaction P = 0.048). In both arms, significantly increased pCR (P < 0.01) were observed with higher sTILs. There was a trend for increased pCR rates in PD-L1-positive tumours, which was significant for PD-L1-tumour cell in durvalumab (P = 0.045) and for PD-L1-immune cell in placebo arm (P = 0.040). The most common immune-related adverse events were thyroid dysfunction any grade in 47%.

CONCLUSIONS

Our results suggest that the addition of durvalumab to anthracycline-/taxane-based NACT increases pCR rate particularly in patients treated with durvalumab alone before start of chemotherapy.

TRIAL REGISTRATION

ClinicalTrials.gov number: NCT02685059.

Locoregional recurrence risk after neoadjuvant chemotherapy: A pooled analysis of nine prospective neoadjuvant breast cancer trials

AIM

This pooled analysis aimed to evaluate locoregional recurrence (LRR) rates of breast cancer (BC) after neoadjuvant chemotherapy (NACT) and to identify independent LRR predictors.

METHODS

10,075 women with primary BC from nine neoadjuvant trials were included. The primary outcome was the cumulative incidence rate of LRR as the first event after NACT. Distant recurrence, secondary malignancy or death were defined as competing events. For identifying LRR predictors, surgery type, pathological complete response (pCR), BC subtypes and other potential risk factors were evaluated.

RESULTS

Median followup was 67 months (range 0-215), overall LRR rate was 9.5%, 4.1% in pCR versus 9.5% in non-pCR patients. Younger age, clinically positive lymph nodes, G3 tumours, non-pCR and TNBC but not surgery type were independent LRR predictors in multivariate analysis. Among BC subtypes, 5-year cumulative LRR rates were associated with higher risk in non-pCR versus pCR patients, which was significant for HR+/HER2- (5.9% vs 3.9%; HR = 2.32 [95%CI 1.22-4.43]; p = 0.011); HR-/HER2+ (14.8% vs 3.1%; HR = 4.26 [94%CI 2.35-7.71]; p < 0.001) and TNBC (18.5% vs 4.2%; HR = 4.10 [95%CI 2.88-5.82]; p < 0.001) but not for HR+/HER2+ (8.1% vs 4.8%; HR = 1.56 [95%CI 0.85-2.85]; p = 0.150). Within non-pCR subgroup, LRR risk was higher for HR-/HER2+ and TNBC vs HR+/HER2- (HR = 2.05 [95%CI 1.54-2.73]; p < 0.001 and HR = 2.77 [95%CI 2.27-3.39]; p < 0.001, respectively).

CONCLUSIONS

This pooled analysis demonstrated that young age, node-positive and G3 tumours, as well as TNBC, and non-pCR significantly increased the risk of LRR after NACT. Hence, there is a clear need to investigate better multimodality therapies in the post-neoadjuvant setting for high-risk patients.

Abstract P6-10-03: Germline (g)BRCA1/2 mutations (m) and hematological toxicities in patients (pts) with triple negative breast cancer (TNBC) treated with neoadjuvant chemotherapy (NACT)

Background: BRCA1/2 genes play a central role in DNA repair. Therefore, pts harboring gBRCA1/2m treated with chemotherapy might be at higher risk of acute hematological toxicities due to the lower level of functional BRCA1/2 protein potentially resulting in more toxicity. Published results are discordant, further data are needed.

Methods: Pts with early TNBC and known gBRCA1/2m treated with anthracycline-taxane based NACT in the GeparQuinto (n=487), GeparSixto (n=291) and GeparOcto (n=393) studies were included. Primary G-CSF prophylaxis was foreseen only for the iddETC arm in GeparOcto. Primary objective was the rate of neutropenia grade (G)3-4 after cycle 1; secondary objectives were the rate of other hematological toxicities G3-4 and the overall toxicity rate after cycle 1 as well as hematological toxicities in gBRCA1/2 pts during the taxane part of chemotherapy.

Results: 209/1171 evaluated pts (17.8%) had a gBRCA1/2m (177 gBRCA1m, 33 gBRCA2m). Median age was 48yrs [21-78].

The rate of neutropenia G3-4 after cycle 1 in gBRCA1/2 wildtype (wt) pts was 35.7% vs 37.4% in gBRCA1/2m (p=0.683), 35.9% in gBRCA1m (p=1.000), 44.8% in gBRCA2m (p=0.330).

gBRCA1/2 mutational status did not predict neutropenia G3-4 at univariate (OR=1.08, 95%CI 0.78-1.48 p=0.658) or multivariate analysis adjusted for age, BMI and treatment (OR=1.26, 95%CI 0.87-1.82 p=0.226).

The overall rate and the rates of other hematological toxicities are shown in the table.

gBRCA1/2 mutational status did also not predict for any other hematological toxicities G3-4 (univariate OR=0.94, 95%CI 0.64-1.40 p=0.773; multivariate OR=0.94, 95%CI 0.62-1.43 p=0.779).

gBRCA1/2 mutational status predicted for hematological toxicities G3-4 under taxane treatment (univariate OR=1.94, 95%CI 1.35-2.77 p&lt;0.001; multivariate OR=2.91, 95%CI 1.55-5.45 p=0.001).

During taxane treatment, the overall rate of hematological toxicities G3-4 in wt pts was 43.1% (n=270) vs 59.5% (n=91) in gBRCA1/2m, p&lt;0.001; anemia G3-4 2.6% (n=16) vs 3.3% (n=5), p=0.584; leucopenia G3-4 32.7% (n=203) vs 47.1% (n=72), p=0.001; neutropenia G3-4 35.8% (n=219) vs 49.3% (n=73), p=0.003; thrombopenia G3-4 1.4% (n=9) vs 4.6% (n=7), p=0.024; febrile neutropenia 5.9% (n=37) vs 4.6% (n=7), p=0.696.

Conclusions: Overall, gBRCA1/2 mutation is not associated with a significantly higher risk of severe hematological toxicities. Under taxane therapy, pts with gBRCA1/2 demonstrate a higher rate of hematological toxicities G3-4, especially neutropenia, compared to wildtype pts, and should therefore be carefully monitored.

Hematological toxicities after cycle 1wildtypegBRCA1/2mp-valuegBRCA1mp-valuegBRCA2mp-valueN%N%N%N%neutropenia G3-432635.77437.40.6836135.91.0001344.80.330febrile neutropenia171.831.41.00010.60.33726.10.130leucopenia G3-424425.83818.20.0212815.80.0041030.30.548anemia G3-420.200.01.00000.01.00000.01.000thrombopenia G3-4111.210.50.70510.60.70400.01.000any hematological toxicities G1-477782.617081.70.76314180.10.4533090.90.344any hematological toxicities G3-442846.38843.60.5337241.90.3171651.60.587

Citation Format: Jenny Furlanetto, Volker Möbus, Andreas Schneeweiss, Kerstin Rhiem, Hans Tesch, Jens-Uwe Blohmer, Kristina Lübbe, Michael Untch, Christoph Salat, Jens Huober, Peter Klare, Rita Schmutzler, Fergus J Couch, Bianca Lederer, Bernd Gerber, Dirk-Michael Zahm, Ingo Bauerfeind, Valentina Nekljudova, Claus Hanusch, Christian Jackisch, Theresa Link, Sibylle Loibl, Peter A Fasching. Germline (g)BRCA1/2 mutations (m) and hematological toxicities in patients (pts) with triple negative breast cancer (TNBC) treated with neoadjuvant chemotherapy (NACT) [abstract]. In: Proceedings of the 2019 San Antonio Breast Cancer Symposium; 2019 Dec 10-14; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2020;80(4 Suppl):Abstract nr P6-10-03.

A Small Hypoxia Signature Predicted pCR Response to Bevacizumab in the Neoadjuvant GeparQuinto Breast Cancer Trial

PURPOSE

In breast cancer, bevacizumab increased pCR rate but not long-term survival and no predictive markers are available to identify patients with long-term benefit from the drug.

EXPERIMENTAL DESIGN

We profiled 289 pretherapeutic formalin-fixed, paraffin-embedded (FFPE) biopsies of HER2-negative patients from the GeparQuinto trial of neoadjuvant chemotherapy ± bevacizumab by exome-capture RNA-sequencing (RNA-seq). In a prospectively planned study, we tested molecular signatures for response prediction. IHC validation was performed using tissue microarrays.

RESULTS

We found strong agreement of molecular and pathologic parameters as hormone receptors, grading, and lymphocyte infiltration in 221 high-quality samples. Response rates (49.3% pCR overall) were higher in basal-like (68.9%) and HER2-enriched (45.5%) than in luminal B (35.7%), luminal A (17.9%), and normal-like (20.0%) subtypes. T-cell (OR = 1.60; 95% confidence interval, 1.21-2.12; P = 0.001), proliferation (OR = 2.88; 95% CI, 2.00-4.15; P < 0.001), and hypoxia signatures (OR = 1.92; 95% CI, 1.41-2.60; P < 0.001) significantly predicted pCR in univariate analysis. In a prespecified multivariate logistic regression, a small hypoxia signature predicted pCR (OR = 2.40; 95% CI, 1.28-4.51; P = 0.006) with a significant interaction with bevacizumab treatment (P = 0.020). IHC validation using NDRG1 as marker revealed highly heterogenous expression within tissue leading to profound loss of sensitivity in TMA analysis, still a significant predictive value for pCR was detected (P = 0.025).

CONCLUSIONS

Exome-capture RNA-seq characterizes small FFPE core biopsies by reliably detecting factors as for example ER status, grade, and tumor-infiltrating lymphocytes levels. Beside molecular subtypes and immune signatures, a small hypoxia signature predicted pCR to bevacizumab, which could be validated by IHC. The signature can have important applications for bevacizumab treatment in different cancer types and might also have a role for novel combination therapies of bevacizumab with immune checkpoint inhibition.

NAB-Paclitaxel Improves Disease-Free Survival in Early Breast Cancer: GBG 69–GeparSepto

PURPOSE

The GeparSepto trial demonstrated that weekly nanoparticle albumin-bound (NAB)–paclitaxel significantly improves the pathologic complete remission rate compared with weekly solvent-based (sb) paclitaxel followed by epirubicin plus cyclophosphamide as neoadjuvant treatment in patients with primary breast cancer (BC). Here, we report data on long-term outcomes.

METHODS

Patients with histologically confirmed primary BC were randomly assigned in a 1:1 ratio to 12 times weekly NAB-paclitaxel 150 mg/m2 (after study amendment, 125 mg/m2) or weekly sb-paclitaxel 80 mg/m2 followed in both arms by four times epirubicin 90 mg/m2 plus cyclophosphamide 600 mg/m2 every 3 weeks. Patients with human epidermal growth factor receptor 2 (HER2)-positive BC received dual antibody treatment with trastuzumab (8 mg/kg loading dose followed by 6 mg/kg every 3 weeks) and pertuzumab (840 mg loading dose followed by 420 mg every 3 weeks) concurrently to chemotherapy and continued for 1 year.

RESULTS

A total of 1,206 patients started treatment, 606 with NAB-paclitaxel and 600 with sb-paclitaxel. After a median follow-up of 49.6 months (range, 0.5 to 64.0 months), 243 invasive disease–free survival (iDFS) events were reported (143 in the sb-paclitaxel and 100 in the NAB-paclitaxel arm). At 4 years, overall patients treated with NAB-paclitaxel had a significantly better iDFS compared with sb-paclitaxel (84.0% v 76.3%; hazard ratio, 0.66; 95% CI, 0.51 to 0.86; P = .002), whereas overall survival did not significantly differ between the two treatment arms (89.7% v 87.2%, respectively; hazard ratio, 0.82; 95% CI, 0.59 to 1.16; P = .260). Long-term follow-up of the treatment-related peripheral sensory neuropathy (PSN) showed a significant decrease of the median time to resolve PSN after NAB-paclitaxel 125 mg/m2 compared with NAB-paclitaxel 150 mg/m2.

CONCLUSION

The significantly higher pathologic complete response rate with NAB-paclitaxel translated into a significantly improved iDFS in patients with early BC as compared with sb-paclitaxel. PSN improved much faster under NAB-paclitaxel 125 mg/m2 compared with NAB-paclitaxel 150 mg/m2.

Post-Mastectomy Radiotherapy After Neoadjuvant Chemotherapy in Breast Cancer: A Pooled Retrospective Analysis of Three Prospective Randomized Trials

BACKGROUND

The impact of locoregional radiotherapy (RT) after neoadjuvant chemotherapy (NACT) and mastectomy in breast cancer patients is currently unclear. Several publications have suggested that patients with a favorable response to NACT might not benefit from RT after mastectomy.

METHODS

A retrospective analysis of three prospective randomized NACT trials was performed. Information on the use of RT was available for 817 breast cancer patients with non-inflammatory breast cancer who underwent mastectomy after NACT within the GeparTrio, GeparQuattro, and GeparQuinto-trials. RT was administered to 676 of these patients (82.7%).

RESULTS

The 5-year cumulative incidence of locoregional recurrence (LRR) was 15.2% (95% confidence interval [CI] 9.0-22.8%) in patients treated without RT and 11.3% in patients treated with RT (95% CI 8.7-14.3%). In the multivariate analysis, RT was associated with a lower risk of LRR (hazard ratio 0.51, 95% CI 0.27-1.0; p = 0.05). This effect was shown especially in patients with cT3/4 tumors, as well as in patients who were cN+ before neoadjuvant therapy, including those who converted to ypN0 after neoadjuvant therapy. In the bivariate analysis, disease-free survival was significantly worse in patients who received RT, however this was not confirmed in the multivariate analysis.

CONCLUSIONS

Our results suggest that RT reduces the LRR rates in breast cancer patients who receive a mastectomy after NACT without an improvement in DFS. Prospective randomized controlled trials such as the National Surgical Adjuvant Breast and Bowel Project B-51/RTOG 1304 trial will analyze whether RT has any benefit in patients who have a favorable response after NACT.

Germline mutation status and therapy response in high-risk early breast cancer: Results of the GeparOcto study (NCT02125344)

573

Background: GeparOcto compared the efficacy of two neoadjuvant treatment (NAT) regimens in high-risk early breast cancer (BC): Sequential intense dose-dense epirubicin, paclitaxel, and cyclophosphamide (iddEPC) and weekly paclitaxel plus non-pegylated liposomal doxorubicin (PM), plus carboplatin (PMCb) in triple-negative BC (TNBC). There was no difference in pathologic complete response (pCR) rates (Schneeweiss et al. Eur J Cancer 2019). Here, we stratified pCR rates according to germline mutation status. Methods: Germline (g) mutation analysis of BRCA1/2 and 16 further BC predisposition genes in 914 patients (pts) enrolled (393 pts with TNBC, iddEPC n = 194, PMCb n = 199; 156 pts with HER2-/HR+ BC, iddEPC n = 75, PM n = 81; and 365 pts with HER2+ BC, iddEPC n = 182, PM n = 183). Results: The gBRCA1/2 mutation prevalence was 17.6% in TNBC, 14.1% in HER2-/HR+ BC and 1.4% in HER2+ BC. Overall, pts with gBRCA1/2 mutations achieved higher pCR rates than gBRCA1/2 wildtype pts (60.4% vs 46.7%, OR 1.74, P = 0.012), with more pronounced effects in the PM(Cb) arm (68.1% vs 45.7%, OR 2.53, P = 0.005). Among gBRCA1/2 wildtype pts, 76 carried mutations in non- BRCA1/2 predisposition genes. pCR rates were similar to those observed in pts without any mutation. Conclusions: Pts with gBRCA1/2 mutations benefitted most from NAT with highest pCR rates achieved in the gBRCA1/2 TNBC / PMCb group. The role of Cb for NAT of gBRCA1/2 TNBC should be further explored. Clinical trial information: NCT02125344. [Table: see text]

Comparison of an automated cartridge-based system for mRNA assessment with central immunohistochemistry in the neoadjuvant GeparX trial

3075

Background: Hormone receptors, HER2 and Ki-67 are prognostic values typically determined for breast cancer (BC) outcome and prediction of therapy response. A RT-qPCR based system, the Xpert Breast Cancer STRAT4, can be used to classify BC tissues regarding their hormone receptor status, HER2 and proliferation via Ki-67. We compared mRNA expression analysis of ER, PR, HER2, and Ki-67 by this automated in-vitro diagnostic platform (GeneXpert) (GX) with central immunohistochemistry (IHC) in a large clinical trial cohort. Methods: BC patients from the prospective GBG neoadjuvant trial GeparX (NCT02682693) (still recruiting) were included in this biomarker project. We used formalin-fixed paraffin embedded (FFPE) pretherapeutical core biopsies with a tumor content > 10%. One 4 µm FFPE tissue section was first processed with the Xpert FFPE Lysis Kit, the sample lysate was placed in the STRAT4 cartridge system and then tested on the GX system in which the purification, amplification and real-time detection took place within two hours automatically. Results: A total of 503 (99%) of the 509 samples had a valid measurement of all four genes. 258 samples (51.3%) of the cohort were classified in central pathology as ER positive, 196 (39%) as PR positive and 78 (15.5%) as HER2-positive, and 421 samples (83.7%) were Ki-67-high ( > 20%). The simple kappa coefficient was for ER = 0.7938, PR = 0.6540, HER2 = 0.8172 and Ki-67 = 0.3655. This indicates, that the measurements for ER, PR and HER2 showed a high correlation between both methods, whereas the measurement of Ki-67 does not. The accuracy between the STRAT4 and IHC was 89.7% for ER, 83.3% for PR, 94.6% for HER2 and 86.7% for Ki-67. According to molecular subgroups, highest accuracy regarding Ki-67, was determined in TNBC (96.2%; luminal: 81.1%; HER2-positive: 76.9%). Conclusions: Our results show a high concordance between standardized central IHC and automated mRNA expression analysis for the most important BC biomarkers ER, PR and HER2. For the proliferation marker Ki-67, the concordance is slightly lower. The STRAT4 assay might offer additional option to conventional methods for BC biomarker assessment, in particular in settings where IHC is not feasible. To determine the clinical validity, additional outcome analyses are necessary. Clinical trial information: NCT02682693.

GeparOLA: A randomized phase II trial to assess the efficacy of paclitaxel and olaparib in comparison to paclitaxel/carboplatin followed by epirubicin/cyclophosphamide as neoadjuvant chemotherapy in patients (pts) with HER2-negative early breast cancer (BC) and homologous recombination deficiency (HRD)

506

Background: The efficacy and toxicity of olaparib in early BC pts with homologous DNA repair deficiency (here defined as HRD score high tumors +/- germline (g) or tumor (t) BRCA mutation) is not well described. GeparOLA investigates olaparib in HER2 negative early BC with HRD. Methods: GeparOLA (NCT02789332) randomized 102 pts to either paclitaxel 80 mg/m² weekly (Pw) plus olaparib 100 mg twice daily for 12 weeks (PwO n = 65) or Pw plus carboplatin (Cb) AUC2 weekly for 12 weeks (PwCb n = 37), both followed by EC. Randomization was stratified by hormone receptor-status (HR+ vs HR-) and age ( < 40 vs ≥40 years). Pts with untreated primary cT2 - cT4a-d or cT1c with either cN+ or pNSLN+ or triple negative or Ki-67 > 20% were included, with either g/t BRCA mutation and/or high HRD score. The primary endpoint is pathological complete response (pCR; ypT0/is ypN0). A one group χ2-test was planned to exclude the pCR rate of ≤55% in PwO→EC arm. Secondary endpoints are other pCR definitions, breast conservation rate, clinical and imaging response, tolerability and safety. Results: A total of 107 pts were randomized between 9/2016 and 7/2018; 106 started treatment. Median age was 47.0 years [range 25.0-71.0]; 36.2% of pts had cT1, 61.0% cT2, 2.9% cT3, and 31.8% cN-positive tumors; G3: 86.8%; Ki-67 > 20%: 89.6%; TNBC 72.6%; confirmed g /tBRCA 1/2 mutation: 60.4%. pCR rate with PwO was 55.1% (90%CI 44.5%-65.3%) vs PwCb 48.6% (90%CI 34.3%-63.2%). Analysis for the stratified subgroups showed higher pCR rates with PwO in the cohorts of pts < 40 years and HR+ pts Clinical trial information: NCT02789332. Conclusions: GeparOla could not exclude a pCR rate of ≤55% in the PwO arm. Subgroup analysis is hypothesis generating and need further confirmation.[Table: see text]

Exome analysis of oncogenic pathways and tumor mutational burden (TMB) in triple-negative breast cancer (TNBC): Results of the translational biomarker program of the neoadjuvant double-blind placebo controlled GeparNuevo trial

509

Background: GeparNuevo (G9) showed a numerical increase in pCR rate of 53% vs 44%; p = 0.287 compared to placebo in TNBC with the addition of the anti-PD-L1 antibody durvalumab (D) to a neoadjuvant anthracycline-taxane containing chemotherapy (Loibl S et al. ASCO 2018). Somatic mutations in malignant cells manifest over the evolutionary history of a tumor. Reports in selected tumor types suggest that TMB may predict clinical outcomes on immune-checkpoint inhibitors (ICI). The clinical relevance of TMB in breast cancer has not been studied widely. Here, we investigated the hypothesis that TMB predicts response to ICI. Methods: Whole exome sequencing was conducted on patient-matched fresh-frozen core biopsies and blood samples with Illumina (n = 149/174). SNVs and indels were called with Mutect and pureCN was used for copy number calls. Mutational signatures were identified as described by Alexandrov et al. (Cell Rep. 3, 2013). Data from G9 were compared to The Cancer Genome Atlas (TCGA) TNBC cohort. Results: A similar genomic landscape was observed between G9 and TCGA with primary mutations in TP53 (69%), c-MYC (26%), BRCA1 (13%), BRCA2 (6%), PIK3CA (11%) and PTEN (11%). Median TMB was 1.52 mut/MB. TMB in G9 was slightly lower than TCGA TNBC. TMB correlated with older age, higher mutation rates in BRCA2, ARID1A, and TP53, and higher burden in variant signatures such as DDR, HRD, GFRs, APOBEC and Alexandrov’s signatures 3 and 6. Continuous TMB predicted pCR in univariate (OR = 1.62, 95%-CI: 1.20 - 2.20, p = 0.0018) and multivariate (OR = 2.06, 95%-CI: 1.33 - 3.20, p = 0.0012) logistic regression models, but did not predict a D effect. After dichotomisation of TMB at the top tertile, 50 patients had high TMB and 29 of these (58%) achieved a pCR, while 99 had low TMB and only 38 of these (38%) had a pCR (p = 0.0242). Conclusions: Results show that TMB may predict pCR in primary TNBC. The trial was financially supported by Astra Zeneca and Celgene. Clinical trial information: NCT02685059.

Correlation of the tumor mutational burden with the composition of the immune cell subpopulations in peripheral blood of triple-negative breast cancer patients undergoing neoadjuvant therapy with durvalumab: Results from the prospectively randomized GeparNuevo trial

588

Background: The GeparNuevo trial is a randomized, double-blind, multi-center phase II trial of neoadjuvant therapy in patients with early-stage triple negative breast cancer (TNBC) investigating the role of durvalumab, an anti-PD-L1 antibody, which blocks PD-L1 binding to PD1 and CD80, in addition to standard chemotherapy with nab-Paclitaxel (nab-Pac) followed by Epirubicin plus Cyclophosphamid (EC; Loibl S et al. ASCO 2018). Since the tumor mutational burden (TMB) has been suggested to be associated with a better outcome of patients undergoing immunotherapy and an increased T cell response, we determined whether there exists a link between TMB and immune cell composition, frequency and function in patients of the GeparNuevo trial. Methods: In order to determine possible predictive and / or prognostic biomarkers, tumor biopsies taken at recruitment from 149 patients out of the 174 enrolled patients underwent deep sequencing in order to determine the TMB. In addition, for 120 patients blood samples were taken at recruitment and during different time points of treatment (after durvalumab pre-treatment, after Nab-Pac and at surgery after EC) and evaluated using multicolor flow cytometry by monitoring the absolute cell counts of T cells, B cells and NK cells as well as the frequency, composition and functionality of different immune cell populations. Results: The TMB of the GeparNuevo cohort was in line with published data with a mean of 1.8 mutations/MB (range 0.02 – 7.65), respectively. Preliminary evaluation demonstrated a significant correlation of TMB with blood parameters, in particular with subsets of CD8+ T cells. Interestingly, the data suggest a negative correlation of TMB with the frequency of effector cells while a positive correlation exists with the effector memory cells at recruitment. In depth analyses of a correlation with treatment arm and clinical responses are currently performed. Conclusions: Using this approach we hope to identify biomarkers, which will allow a better selection of TNBC patients undergoing specific immunotherapies. Clinical trial information: NCT02685059.

Development of central nervous system metastases as a first site of metastatic disease in breast cancer patients treated in the neoadjuvant trials GeparQuinto and GeparSixto

Background

The incidence of central nervous system (CNS) metastases in breast cancer patients is rising and has become a major clinical challenge. Only few data are published concerning risk factors for the development of CNS metastases as a first site of metastatic disease in breast cancer patients. Moreover, the incidence of CNS metastases after modern neoadjuvant treatment is not clear.

Methods

We analyzed clinical factors associated with the occurrence of CNS metastases as the first site of metastatic disease in breast cancer patients after neoadjuvant treatment in the trials GeparQuinto and GeparSixto (n = 3160) where patients received targeted treatment in addition to taxane and anthracycline-based chemotherapy.

Results

After a median follow-up of 61 months, 108 (3%) of a total of 3160 patients developed CNS metastases as the first site of recurrence and 411 (13%) patients had metastatic disease outside the CNS. Thirty-six patients (1%) developed both CNS metastases and other distant metastases as the first site of metastatic disease. Regarding subtypes of the primary tumor, 1% of luminal A-like (11/954), 2% of luminal B-like (7/381), 4% of HER2-positive (34/809), and 6% of triple-negative patients (56/1008) developed CNS metastases as the first site of metastatic disease.

In multivariate analysis, risk factors for the development of CNS metastases were larger tumor size (cT3–4; HR 1.63, 95% CI 1.08–2.46, p = 0.021), node-positive disease (HR 2.57, 95% CI 1.64–4.04, p < 0.001), no pCR after neoadjuvant chemotherapy (HR 2.29, 95% CI 1.32–3.97, p = 0.003), and HER2-positive (HR 3.80, 95% CI 1.89–7.64, p < 0.001) or triple-negative subtype (HR 6.38, 95% CI 3.28–12.44, p < 0.001).

Conclusions

Especially patients with HER2-positive and triple-negative tumors are at risk of developing CNS metastases despite effective systemic treatment. A better understanding of the underlying mechanisms is required in order to develop potential preventive strategies.

Abstract P1-11-10: Efficacy of NEPA as antiemetic prophylaxis in breast cancer patients receiving highly or moderately emetogenic chemotherapy – Interim results of a German prospective, non-interventional study

Background

The oral fixed dose combination of netupitant and palonosetron NEPA has been approved for the prevention of acute and delayed chemotherapy-induced nausea and vomiting (CINV) in cancer patients receiving cisplatin-based highly emetogenic (HEC) or moderately emetogenic chemotherapy (MEC). The primary objective of the prospective, non-interventional study (NIS) AkyPRO is the evaluation of quality of life in adults receiving MEC or HEC and NEPA for CINV prevention. Secondary endpoints are efficacy and safety of NEPA. Here we present an interim analysis of NEPA efficacy in the subgroup of breast cancer patients, who represent the largest subgroup (66%) of enrolled patients. Since September 2015, 2427 patients have been enrolled, of whom 986 are breast cancer patients.

Methods

The NIS has been designed to evaluate NEPA in 2,500 cancer patients receiving single day or two day MEC or HEC. QoL is recorded by FLIE questionnaires. Efficacy (complete response (CR, no vomiting, no rescue medication)), additional medication, and adverse events are recorded in patient diaries over three consecutive chemotherapy cycles. Additionally, physicians report their efficacy assessments of NEPA online, using an eCRF.

Results

At the cut-off date November 11, 2017, 2427 patients had been enrolled in the study. For the interim analysis 986 breast cancer patients were evaluated who had been fully documented in the eCRF at the cut-off date.

95% had an ECOG performance status of 0 or 1. 51% received adjuvant, 44% neoadjuvant, and 5% palliative chemotherapy. 80% of patients received HEC, mostly (79%) anthracycline/cyclophosphamide (AC) combinations. Of the women receiving MEC, the majority were treated with carboplatin-based regimens (9%). 7% of patients received other MEC regimens.

81.4-82.8 % of patients reported CR in cycles 1-3 and more than 93% of patients reported no emesis during the 3 treatment cycles covered in the patient diaries. No significant nausea was reported by 62.7-64.2% of patients.

Physicians rated the efficacy of the antiemetic prophylaxis with NEPA using the 4 categories very good, good, satisfactory, and poor. In cycles 1 and 2, more than 89% of physicians rated the efficacy of NEPA very good or good. In cycle 3, 90.6% rated it very good or good. In addition to reporting CR, nausea and emesis episodes in their patient diaries, patients used the same 4 categories to assess the efficacy of NEPA at the end of each treatment cycle. Efficacy assessments of physicians and patients were very similar, with 87% of patients choosing very good or good in cycle 1 compared to 89% of physicians.

NEPA was well tolerated. Low-grade constipation (14.9%) and insomnia (8.3%) were the most frequent treatment-related adverse event.

Conclusion

In this real life study, NEPA was effective in the prevention of CINV in the subgroup of breast cancer patients receiving HEC or MEC. The efficacy assessments by patients and physicians were comparable, with approximately 90% good or very good efficacy for 3 consecutive cycles. More than 93% of patients reported no emesis and more than 81% reported CR during the 5 days post-chemotherapy during all 3 cycles. The study is ongoing.

Citation Format: Schilling J, Hielscher C, Hanusch C, Kurbacher C, Busch S, Karthaus M. Efficacy of NEPA as antiemetic prophylaxis in breast cancer patients receiving highly or moderately emetogenic chemotherapy – Interim results of a German prospective, non-interventional study [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr P1-11-10.

Abstract OT1-05-05: REASSURE- Effects of Reiki as supportive treatment during chemotherapy of breast cancer: A prospective, randomized, controlled clinical trial

Background: Every seventh to eighth woman is diagnosed with breast cancer in her life. Next to surgery and radiotherapy most of them receive (neo)adjuvant chemotherapy, which comes along with adverse effects. Complementary and alternative medicine (CAM) like Reiki can reduce these effects. Reiki is a Far Eastern method that promotes healing on a physical, mental and emotional level and activates self-healing powers. REASSURE examines the effects of Reiki on quality of life and taxane-induced polyneuropathy during chemotherapy.

Methods: REASSURE is a prospective, randomized, controlled, two-armed clinical trial, in which patients with breast cancer receive chemotherapy and Reiki (18 times) or chemotherapy and sport (18 times). During chemotherapy and before and after every Reiki- or sport-session the patients fill out standardized questionnaires (e.g. FACT/GOG-NTX Version 4). Primary endpoint is the comparison of quality of life at the end of chemotherapy between Reiki and sport based on the FACT/GOG-NTX score by T-Test. Secondary endpoint is the comparison of the taxane-induced polyneuropathy at the end of chemotherapy between the two groups. Also short-term effects before and after the Reiki- and sport-session will be examined. A power of 1-β = 0.8, a bilateral probability of error of α = 0.05, a minimum relevant difference deltaθ = 4 and a pooled standard deviation of 11 for the two-sided T-Test result in case numbers of 2 x 120 = 240 patients.

Conclusion: REASSURE is the most comprehensive prospective study to the effects and the feasibility of Reiki on breast cancer patients during chemotherapy so far.

Since July 2015, 138 patients have been enrolled at three different centers. Currently 63 patients in total (39 patients of the Reiki-group and 24 patients of the sport-group) have completed the study. 24 Reiki-patients and 36 sport-patients are counted as dropouts because of reasons like incomplete data records, discontinuation of chemotherapy, not enough time or energy for Reiki- or sport-sessions or other reasons.

Sponsor: This is a collaborative study of the Department of Obstetrics and Gynecology, Klinikum rechts der Isar, Technische Universität München (TUM), Munich, Germany, Rotkreuzklinikum München, Frauenklinik, Munich, Germany, Department of Gynaecology, Städtisches Klinikum München Harlaching, Munich, Germany and the ProReiki – der Berufsverband e.V., Berlin, Germany.

Contact Information: For further information contact Sophie Katzendobler via sophie.katzendobler@gmail.com or the leading physician Dr. Johannes Ettl via johannes.ettl@tum.de.

Citation Format: Katzendobler S, Haunreiter L, Zander L, Schmidt R, Andrulat A, Münch K, Hanusch C, Napieralski R, Petri I, Ettl J. REASSURE- Effects of Reiki as supportive treatment during chemotherapy of breast cancer: A prospective, randomized, controlled clinical trial [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr OT1-05-05.