Austrian Breast & Colorectal Cancer Study Group

Science from the heart of Europe

HER2/CEP17 ratio is associated with pCR after HER2-directed neoadjuvant treatment in the phase III NeoALTTO trial

Christian F. Singer, Franz Koenig, Stephanie Kacerovsky-Strobl, Sabine Danzinger, Christine Brunner, Christoph Suppan, Christine Deutschmann, Marija Balic, Richard Greil, Daniel Egle, Evandro de Azambuja, Serena Di Cosimo, Anup Choudhury, Michael Gnant

The Breast 85 (2026) 104679
Published by Elsevier Ltd.
Available online 22 December 2025
DOI: https://doi.org/10.1016/j.breast.2025.104679

---

40P An artificial intelligence model predicts Ki67 from H&E-stained whole slide images in breast cancer

D. Kates Harbeck, M. Filipits, D. Hlauschek, G. Rinnerthaler, S.P. Gampenrieder, K. Haider, W.H. Hulla, R.E. Kates, H.Kreipe, M. Christgen, O. Gluz, S. Mahner, J. Zhang, H. Pinckaers, G. Smit, A. Piehler, J.R. Griffin, N. Harbeck, M.I. Gnant

ESMO Real World Data and Digital Oncology
Volume 10, Supplement 100239, November 2025
DOI: https://doi.org/10.1016/j.esmorw.2025.100239

---

ESR1, PGR, ERBB2, and MKi67 mRNA expression in diagnostic core biopsies from breast cancer patients of the ABCSG Trial 34

Stephanie Kacerovsky-Strobl, Christine Deutschmann, Dominik Hlauschek, Zsuzsanna Bago-Horvath, Christian F. Singer, Rupert Bartsch, Richard Greil, Karl Sotlar, Gabriel Rinnerthaler, Edgar Petru, Sigurd F. Lax, Daniel Egle, Angelika Pichler, Koppány Bodó, Andreas L. Petzer, Farid Moinfar, Jodi Weidler, Michael Bates, Peter Dubsky, Michael Gnant, Martin Filipits

The Breast
DOI: https://doi.org/10.1016/j.breast.2025.104633

---

Palbociclib with adjuvant endocrine therapy in early breast cancer: 5-year follow-up analysis of the global multicenter, open-label, randomized phase III PALLAS trial (ABCSG-42/AFT-05/PrE0109/BIG-14-13)

E. L. Mayer, D. Hlauschek, M. Gnant, P. J. O’Brien, M. Bellet-Ezquerra, M. P. Goetz, M. Ruiz-Borrego, A. Chan, K. Clifton, D. Egle, D. Lake, P. Cabrera, T. Mamounas, G. Pristauz-Telsnigg, Z. Dayao, M. Gil Gil, D. Cameron, T. Traina, P. G. Morris, D. Sabanathan, G. Rinnerthaler, J. Meisel, A. Prat, A. C. Wolff, L.-M. Tseng, C. Isaacs, C. F. Singer, G. Rubovszky, T. Foukakis, J. Jassem, E. P. Winer, M. Vetter, J. Federmann, O. Metzger, C. Schurmans, E. Gauthier, D. R. Lu, C. Fesl, A. Dueck & A. DeMichele

Annals of Oncology
Articles in Press, October 17, 2025 – Open access
https://doi.org/10.1016/j.annonc.2025.10.003

---

Surgical outcome parameters in breast cancer: A survey comparing oncoplastic and non-oncoplastic surgeons as well as certified with non-certified breast health centers

Wimmer K, Gordon K, Emmanuel K, Steger G, Gnant M, Weber WP, Fitzal F

Breast Care
Published online: October 3
DOI: 10.1159/000548657

---

Prevalence and prognosis of patients with breast cancer eligible for adjuvant abemaciclib or ribociclib: a nationwide population-based study

Xingrong Liu, Behnaz Binicy, Balazs Acs, Louise Eriksson Bergman, Sibylle Loibl, Michael Gnant, Michael Untch, Antonios Valachis, Jonas Bergh, Johan Hartman, Theodoros Foukakis and Alexios Matikasa

The Lancet Regional Health – Europe 2025;59: 101471
Available online 29 September 2025
https://doi.org/10.1016/j.lanepe.2025.101471

---

A core outcome set for locoregional treatment reporting in neoadjuvant systemic breast cancer treatment trials

PRECEDENT Study Group, Shelley Potter*, Kerry N L Avery, Rosina Ahmed, Jana De Boniface, Sanjoy Chatterjee, David Dodwell, Peter Dubsky, Jingjing Federmann, Sandra Finestone, Michael Gnant, Dominik Hlauschek, Hiroji Iwata, Michael Y Jiang, Orit Kaidar-Person, Han-Byoel Lee, Mairead Mackenzie, Anne Meyn, Phillip Poortmans, Fiorita PoulakakiAndrea L Richardson, Karla A Sepulveda, Andrew J Spillane, Alastair M Thompson, Gustavo Werutsky, Philipp Wittmann, Jean L Wright, Nicholas Zdenkowski, Katherine Cowan, Stuart A McIntosh

BMJ Open 2024;14:e084488.
doi:10.1136/bmjopen-2024-084488

---

New perspectives in the management of triple-negative breast cancer

Bartsch R, Bago-Horvath Z, Egle D, Gampenrieder SP, Grünberger B, Heibl S, Marhold M, Preuss C, Rinnerthaler G, Strasser-Weippl K, Suppan C, Singer CF, Gnant M

Breast Care (2025), Published by S. Karger AG, Basel
Published online: August 15, 2025
https://doi.org/10.1159/000547988

---

Extending the duration of endocrine treatment for early breast cancer: patient-level meta-analysis of 12 randomised trials of aromatase inhibitors in 22 031 postmenopausal women already treated with at least 5 years of endocrine therapy

Early Breast Cancer Trialists’ Collaborative Group (EBCTCG)*
*Austrian Breast Cancer Study Group (ABCSG), Vienna, Austria – M Balic, R Bartsch, C Fesl, F Fitzal, H Fohler, M Gnant, R Greil, R Jakesz, C Marth, B Mlineritsch, G Pfeiler, C F Singer, L Sölkner, G G Steger, H Stöger

The Lancet
Vol 406 August 9, 2025
https://doi.org/10.1016/S0140-6736(25)01013-X

---

Was kommt nach CDK4/6- Inhibition? Perspektiven beim fortgeschrittenen Mammakarzinom

Vanessa Castagnaviz, Anna Fenzl, Michael Gnant, Rupert Bartsch

Wiener klinische Wochenschrift
DFP-Fortbildung
Published: 31 July 2025
https://doi.org/10.1007/s00508-025-02582-y

---

Hormonal factors predictive of fertility in patients with breast cancer interrupting adjuvant endocrine therapy to attempt pregnancy in POSITIVE trial

Isabelle Demeestere, Samuel M. Niman, Ann H. Partridge, Daniela S. Diego, Roswitha Kammler, Monica Ruggeri, Marco Colleoni, Chikako Shimizu, Cristina Saura, Karen A. Gelmon, Anna B. Saetersdal, Judith R. Kroep, Audrey Mailliez, Frederic Amant, Manuel Ruız-Borrego, Jeong Eon Lee, Akemi Kataoka, Janice M. Walshe, Junko Takei, Simona Borstnar, Virginia F. Borges, Christobel Saunders, Snezana Susnjar, Vesna Bjelic-Radisic, Fatima Cardoso, Jane Lowe Meisel, Jennifer F. Kawwass, Tanja Spanic, Sarra El-Abed, Martine Piccart, Larissa A. Korde, Aron Goldhirsch,Richard D. Gelber, Olivia Pagani, Hatem A. Azim Jr., Fedro A. Peccatori, for the International Breast Cancer Study Group and the POSITIVE Trial Collaborators

The Breast. Published by Elsevier Ltd.
Available online 26 July 2025
https://doi.org/10.1016/j.breast.2025.104547

---

Breastfeeding After Hormone Receptor–Positive Breast Cancer: Results From the POSITIVE Trial

Fedro A. Peccatori, Samuel M. Niman, Ann H. Partridge, Monica Ruggeri, Marco Colleoni, Cristina Saura, Chikako Shimizu, Anna B. Satersdal, Judith R. Kroep, Karen Gelmon, Frederic Amant, Audrey Mailliez, Halle C.F. Moore, Manuel Ruiz-Borrego, Janice M. Walshe, Virginia F. Borges, Andrea Gombos, Akemi Kataoka, Christine Rousset-Jablonski, Simona Borstnar, Junko Takei, Jeong E. Lee, Christobel Saunders, Vesna Bjelic-Radisic, Snezana Susnjar, Fatima Cardoso, Natalie J. Klar, Teresa Ferreiro, Sarra El-Abed, Martine Piccart, Larissa A. Korde,

Aron Goldhirsch, Richard D. Gelber,  Olivia Pagani, and Hatem A. Azim Jr,  for the International Breast Cancer Study Group and the POSITIVE Trial Collaborators

J Clin Oncol 43:2712-2719
Published July 9, 2025
https://doi.org/10.1200/JCO-24-02697

---

Genomic profiling of primary tumor and lymph node metastasis in patients with clinically node-positive breast cancer: Prospective cohort study within TAXIS (OPBC-03, SAKK 23/16, IBCSG 57-18, ABCSG-53, GBG 101)

Michael Knauer, Daniel Egle, Stefanie Hayoz, Ákos Sávolt, Christoph Tausch, Susanne Bucher, Colin Simonson, Rok Satler, Jörg Heil, Inga Bekes, Vesna Bjelic-Radisic, William Audeh, Giang Thanh Lam, Andrea Menicucci, Simone Muenst, Valerijus Ostapenko, Christian Kurzeder, Martin Heidinger, Walter P. Weber 

European Journal of Cancer
Available online 18 June 2025, 115585
https://doi.org/10.1016/j.ejca.2025.115585

---

Abstract P4-01-26: The Xpert® Breast Cancer Insight test predicts distant recurrence and overall survival in estrogen receptor-positive, HER2-negative early breast cancer: A validation study in ABCSG Trial 8 

Martin Filipits; Viktoria Gruber; Christian F. Singer; Florian Fitzal; Zsuzsanna Bago-Horvath; Richard Greil; Marija Balic; Peter Regitnig; Nancy Toro-Bauer; Wolfgang Hulla; Daniel Egle; Daneida Lizarraga; Alice Baker; Rajesh Kaldate; Malini Satya; Jodi Weidler; Michael Bates; Scott Campbell; Dominik Hlauschek; Peter Dubsky; Michael Gnant

Clinical Cancer Research
Volume 31, Issue 12_Supplement
15 June 2025
https://doi.org/10.1158/1557-3265.SABCS24-P4-01-26

---

Abstract P2-03-30: Association of ctDNA in patients with long-term outcome of breast cancer patients undergoing neoadjuvant treatment in the randomized ABCSG 34 clinical trial 

Daniel Egle; Dominik Hlauschek; Simon Gampenrieder; Gabriel Rinnerthaler; Christian Singer; Georg Pfeiler; Rupert Bartsch; Gregor Huber; Angelika Pichler; Edgar Petru; ZsuZsanna Bago-Horvath; Anna Kermanidis; Christian Fesl; Ricarda Graf; Sabrina Weber; Nadia Dandachi; Martin Filipits; Michael Gnant; Ellen Heitzer; Marija Balic

Clinical Cancer Research
Volume 31, Issue 12_Supplement
15 June 2025
https://doi.org/10.1158/1557-3265.SABCS24-P2-03-30

---

Abstract PS3-03: Vaccination with MUC-1-targeting tecemotide improves Survival of patients receiving neo-adjuvant chemotherapy for early breast cancer: Results from the Prospective Randomized ABCSG 34 Trial 

Christian F. Singer; Dominik Hlauschek; Georg Pfeiler; Daniel Egle; Rupert Bartsch; Christoph Suppan; Angelika Pichler; Edgar Petru; Richard Greil; Margaretha Rudas; Michael Seifert; Gregor Huber; Andreas Petzer; Florian Fitzal; Zsuzsanna Bago-Horvath; Martin Filipits; Lidija Soelkner; Christian Fesl; Michael Gnant

Clinical Cancer Research
Volume 31, Issue 12_Supplement
15 June 2025
https://doi.org/10.1158/1557-3265.SABCS24-PS3-03

---

Abstract P2-01-24: Immune activation of tumor cells and microenvironment as assessed by PD-L1 expression and interferon gamma signaling predict long term disease-free and overall survival: Results of the prospective randomized neoadjuvant ABCSG 34 trial

Ulrike M. Heber; Dominik Hlauschek; Christian F. Singer; Daniel Egle; Richard Greil; Ruth Helfgott; Gregor Huber; Elisabeth Müller-Holzner; Cornelia Hauser-Kronberger; Margaretha Rudas; Georg Pfeiler; Rupert Bartsch; Sigurd Lax; Martin Filipits; Gabriel Rinnerthaler; Michael Gnant; Zsuzsanna Bago-Horvath

Clinical Cancer Research
Volume 31, Issue 12_Supplement
15 June 2025
https://doi.org/10.1158/1557-3265.SABCS24-P2-01-24

---

The impact of analysis methodology details on invasive breast cancer-free survival in randomized clinical trials

D. Hlauschek, C. Fesl & M. Gnant

ESMO Open
Volume 10, Issue 7, July 2025
Published online: June 11, 2025
https://doi.org/10.1016/j.esmoop.2025.105324

---

Quality-of-life and symptom severity in the PALLAS randomized trial of palbociclib with adjuvant endocrine therapy in early breast cancer (AFT-05, ABCSG-42, BIG-14-03, PrE0109)

M.J. Naughton, D.M. Zahrieh, M. Gnant, N. Zdenkowski, J. Lemieux, J.J. Mao, V. Bjelic Radisic, E. Shinn, M. Balic, C. Thomssen, J.L. Meisel, G.M. Ruiz, S. Loibl, C. Isaacs, D. Cameron, F.M. Henao-Carrasco, M.P. Goetz, C.F. Singer, G. Werutsky, H.S. Rugo, M. Vetter, L.-M. Tseng, K. Miller, F. Fitzal, J.M. Gil, H. Park, B. Linderholm, E. Bajetta, Z. Dayao, A. Prat, K. Ehrhardt, O. Metzger, A. Arahmani, E.H. Law, A.H. Partridge, L.A. Carey, A. Zoroufy, A.C. Dueck, P. O’Brien, D. Hlauschek, A. DeMichele, E.L. Mayer 

ESMO Open
Volume 10, Issue 6, June 2025, 105120
https://doi.org/10.1016/j.esmoop.2025.105120

---

The future of surgical research

Michael Gnant

British Journal of Surgery, Volume 112, Issue 6
June 2025, znaf095
https://doi.org/10.1093/bjs/znaf095

---

St. Gallen/Vienna 2025
Summary of Key messages on therapy in Early Breast Cancer from the 2025 St. Gallen International Breast Cancer Conference (SGBCC)

Nina Ditsch, Michael Gnant, Christoph Thomssen, Nadia Harbeck

Breast Care 
Published online: May 03, 2025
https://doi.org/10.1159/000546080

---

BRCA1/2 and Other Predisposition Genes in High-Risk Hormone Receptor+/Human Epidermal Growth Factor Receptor 2– Breast Cancer Treated With Endocrine Therapy With or Without Palbociclib: A Secondary PENELOPE-B Study Analysis

Eric Hahnen, Jan Hauke, Karen Gelmon, Frederik Marme, Corinna Ernst, Miguel Martin, Michael Untch, Herve Bonnefoi, Erik Knudsen, Seock-Ah Im, Angela DeMichele, Laura Van’t Veer, Sung-Bae Kim, Harry Bear, Nicole McCarthy, Kerstin Rhiem, Nicholas Turner, Agnieszka Witkiewicz, Federico Rojo, Martin Filipits, Lesley-Ann Martin, Peter A. Fasching, Christian Schem, Kerstin Becker, José A. García-Sáenz, Catherine M. Kelly, Toralf Reimer, Masakazu Toi, Hope S. Rugo, Carsten Denkert, Michael Gnant, Andreas Makris, Yuan Liu, Olga Valota, Barbel Felder, Karsten Weber, Valentina Nekljudova, and Sibylle Loibl

JCO Precision Oncology
April 10, 2025
https://doi.org/10.1200/PO-24-00742

---

Augmenting Insufficiently Accruing Oncology Clinical Trials Using Generative Models: Validation Study

Samer El Kababji; Nicholas Mitsakakis; Elizabeth Jonker; Ana-Alicia Beltran-Bless; Gregory Pond; Lisa Vandermeer; Dhenuka Radhakrishnan; Lucy Mosquera; Alexander Paterson; Lois Shepherd; Bingshu Chen; William Barlow; Julie Gralow; Marie-France Savard; Christian Fesl; Dominik Hlauschek; Marija Balic; Gabriel Rinnerthaler; Richard Greil; Michael Gnant; Mark Clemons; Khaled El Emam

J Med Internet Res 2025 | vol. 27 | e66821
https://www.jmir.org/2025/1/e66821

---

CAMBRIA-1 & CAMBRIA-2 phase III trials: camizestrant versus standard endocrine therapy in ER+/HER2– early breast cancer

Erika P. Hamilton, Sibylle Loibl, Thomas Bachelot, Michael Gnant, Naoki Niikura, Yeon Hee Park, Sara M. Tolaney, Barbara Pistilli, Priya Rastogi, Kamal S. Saini, Ioanna Gioni, Simon Johnston, Raquel Nunes, Angela Quintana, Mary Stuart, Emilia Syta, Andrew Walding, Teresa Klinowska and Ingrid A. Mayer

Future Oncology
Published online: 27 Feb 2025
https://doi.org/10.1080/14796694.2025.2459548

---

Validation of the CTS5 in four prospective, multicenter, randomized ABCSG trials

Kerstin Wimmer, Dominik Hlauschek, Marija Balic, Georg Pfeiler, Richard Greil, Christian F. Singer, Stefan Halper, Günther Steger, Christoph Suppan, Simon Peter Gampenrieder, Ruth Helfgott, Daniel Egle, Martin Filipits, Raimund Jakesz, Lidija Sölkner, Christian Fesl, Michael Gnant, Florian Fitzal on behalf of the Austrian Breast & Colorectal Cancer Study Group

The Breast, Volume 80104415 April 2025
Available online 19 February 2025
https://doi.org/10.1016/j.breast.2025.104415

---

Impact of adding palbociclib on treatment adherence to ongoing adjuvant endocrine treatment in the global randomized PALLAS randomized trial in patients with early breast cancer

Eileen Shinn · David Zahrieh · Angela DeMichele · Nick Zdenkowski · Julie Lemieux · Jun Mao · Vesna Bjelic‑Radisic · Michelle J. Naughton · Georg Pfeiler · Karen Gelmon · Justin M. Balko · Daniel Egle · Gabriele Zoppoli · Tiffany Traina · Miguel Martin Jimenez · Silvia Antolin Novoa · Tufia Haddad · Arlene Chan · Alistair Ring · Antonio Wolff · William Fraser Symmans · Jose Ponce Lorenzo · Dhanusha Sabanathan· Hal J. Burstein · Zbigniew Ireneusz Nowecki · Gunda Pristauz‑Telsnigg · Adam Brufsky · Meritxell Bellet‑Ezquerra · Theodoros Foukakis · Yelena Novik · Gabor Rubovszky · Christian F. Singer · Karoline Muehlbacher · Otto Metzger Filho · Theodora Goulioti · Ernest Law· Ann H. Partridge · Lisa A. Carey · Alex Zoroufy · Dominik Hlauschek · Christian Fesl · Erica L. Mayer · Michael Gnant

Breast Cancer Research and Treatment
11 February 2025
https://doi.org/10.1007/s10549-025-07653-2

---

Dynamics of molecular heterogeneity in high-risk luminal breast cancer—From intrinsic to adaptive subtyping

Carsten Denkert, Sivaramakrishna Rachakonda, Thomas Karn, Karsten Weber, Miguel Martin, Frederik Marmé, Michael Untch, Hervé Bonnefoi, Sung-Bae Kim, Sabine Seiler, Harry D. Bear, Agnieszka K. Witkiewicz, Seock-Ah Im, Angela DeMichele, Anika Pehl, Laura van’t Veer, Nicole McCarthy, Thorsten Stiewe, Paul Jank, Karen A. Gelmon, José A. García-Sáenz, Christina C. Westhoff, Catherine M. Kelly, Toralf Reimer, Bärbel Felder, Mireia Melé Olivé , Erik S. Knudsen, Nicholas Turner, Federico Rojo, Wolfgang D. Schmitt, Peter A. Fasching, Julia Teply-Szymanski, Zhe Zhang, Masakazu Toi, Hope S. Rugo, Michael Gnant, Andreas Makris, Johannes Holtschmidt, Valentina Nekljudova, and Sibylle Loibl

Cancer Cell 43, 232–247, February 10, 2025 , Published by Elsevier Inc.
https://doi.org/10.1016/j.ccell.2025.01.002

---

Outcomes in stage IIA versus stage IIB/III in the PALLAS trial [ABCSG-42/AFT-05/PrE0109/BIG-14-13])

A. DeMichele, A. C. Dueck, D. Hlauschek et al.

Published 23 January 2025
Breast Cancer Research 27, 12
https://doi.org/10.1186/s13058-024-01941-3

---

Efficacy and Safety of CDK4/6 Inhibitors: A Focus on HR+/HER2− Early Breast Cancer

Eva Valentina Klocker, Daniel Egle, Rupert Bartsch, Gabriel Rinnerthaler, Michael Gnant

Drugs
Published: 17 January 2025
https://doi.org/10.1007/s40265-024-02144-y

---

Neoadjuvant atezolizumab in combination with dual HER2 blockade plus epirubicin in women with early HER2-positive breast cancer: the randomized phase 2 ABCSG-52/ATHENE trial

Gabriel Rinnerthaler, Daniel Egle, Rupert Bartsch, Clemens A. Schmitt, Andreas Petzer, Marija Balic, Edgar Petru, Ursula Denison, Christian F. Singer, Vesna Bjelic-Radisic, Simon Peter Gampenrieder, Michael Knauer, Karl Sotlar, Christine Brunner, Florian Posch, Dominik Hlauschek, Lidija Sölkner, Zsuzsanna Bago-Horvath, Martin Filipits, Manuela Gili, Magdalena Ritter, Verena Wieser, Carmen Albertini, Nadja Zaborsky, Lukas Weiss, Maximilian Marhold, Bruno Schneeweiss, Renate Pusch, Michael Gnant & Richard Greil 

Nature Cancer
Published: 16 January 2025
https://doi.org/10.1038/s43018-024-00890-2

---

Drug-drug interactions between palbociclib and proton pump inhibitors in early breast cancer: an exploratory analysis of PALLAS (ABCSG-42/AFT-05/BIG-14-13/PrE0109)

Agostinetto, G. Pfeiler, D. Hlauschek, E.L. Mayer, M. Lambertini, E. de Azambuja, M. Bellet-Ezquerra, J.L. Meisel, G. Rubovszky, N. Zdenkowski, Y. Novik, M. Ruiz-Borrego, K.A. Gelmon, E.P. Mamounas, H. Iwata, D.R. Lu, L. Soelkner, C. Fesl, M. Gnant, A. DeMichele

ESMO Open
Volume 10, Issue 1, January 2025, 104096
https://doi.org/10.1016/j.esmoop.2024.104096

---

HER2 and HER3 expression during neoadjuvant treatment of HER2-negative early breast cancer: potential for biomarker-driven sequencing of T-DXd and HER3-DXd

Christian Fridolin Singer, Stephan Wenzel Jahn, Dominik Hlauschek, Ulrike Maria Heber, Charlotte Mang-Manger, Daniel Egle, Marija Balic, Angelika Pichler, Georg Pfeiler, Stephanie Kacerovsky-Strobl, Christoph Suppan, Magdalena Ritter, Edgar Petru, Richard Greil, Zsuzsanna Bago-Horvath, Christine Deutschmann, Günther Georg Steger, Michael Seifert, Florian Fitzal, Rupert Bartsch, Anu Santhanagopal, Jana Machacek-Link, Dalila Sellami, Magdalena Schwarz, Christian Fesl, Lidija Sölkner, Stephen Esker, Martin Filipits, Michael Gnant on behalf of the Austrian Breast and Colorectal Cancer Study Group Cancer Communications

Cancer Communications 2025;1–5.
2025 Jan 6. doi: 10.1002/cac2.12657. Online ahead of print.
https://doi.org/10.1002/cac2.12657