Aleix Prat, Director of the Clínic Barcelona Comprehensive Cancer Center at Barcelona Clinical Hospital, shared a post on LinkedIn:
“2025 has been a very special year for HER2DX.
Looking back, it’s been quite striking to see how different pieces have come together to give a much more complete picture of what HER2DX captures and how it can be used.
In 2025, we contributed to 7 articles that, together, tell a coherent story:
• A large individual patient-level meta-analysis (IPLM) of more than 2,500 patients validating the HER2DX risk score in early HER2-positive breast cancer. HER2DX pCR score was validated in a ILPM in 2023. Very few biomarkers meet this bar.
Title: HER2DX and survival outcomes in early-stage HER2-positive breast cancer: an individual patient-level meta-analysis
Authors: Guillermo Villacampa, Tomás Pascual, Paolo Tarantino, Javier Cortés, José Perez-García, Antonio Llombart-Cussac, Pierfranco Conte, Mario Mancino, Valentina Guarneri, Maria Vittoria Dieci, Adrienne G Waks, Francesco Schettini, Fara Brasó-Maristany, Gaia Griguolo, Beatriz Alonso de Castro, Cristina Reboredo, Silvia Antolín, Coralia Bueno-Muiño, Isabel Echavarría, Sara López-Tarruella, Tatiana Massarrah, María del Monte-Millán, Miguel Martín, Wesley Buckingham, Joel S Parker, Ana Vivancos, Kornelia Polyak, Otto Metzger Filho, Antonio C Wolff, Angela DeMichele, Nadine M Tung, Charles M Perou, Laia Paré, Patricia Villagrasa, Aleix Prat, Sara M Tolaney
Title: Association of HER2DX with pathological complete response and survival outcomes in HER2-positive breast cancer
Authors: G. Villacampa, N.M. Tung, S. Pernas, L. Paré, C. Bueno-Muiño, I. Echavarría, S. López-Tarruella, M. Roche-Molina, M. del Monte-Millán, M. Marín-Aguilera, F. Brasó-Maristany, A.G. Waks, T. Pascual, O. Martínez-Sáez, A. Vivancos, P.F. Conte, V. Guarneri, M. Vittoria Dieci, G. Griguolo, J. Cortés, A. Llombart-Cussac, M. Muñoz, M. Vidal, B. Adamo, A.C. Wolff, A. DeMichele, P. Villagrasa, J.S. Parker, C.M. Perou, A. Fernandez-Martinez, L.A. Carey, E.A. Mittendorf, M. Martín, A. Prat, S.M. Tolaney
• A prospective real-world study in routine practice in Spain, across 12 hospitals and 34 medical oncologists, showing that HER2DX actually changes clinical decisions and that the pCR score predicts pCR.
Title: Clinical decision impact of HER2DX, an algorithm-powered genomic diagnostic in early-stage HER2-positive breast cancer: results from a prospective real-world study
Authors: O. Martínez-Sáez, M. Tapia, M. Marín-Aguilera, E. Hernández-Illán, C. Tébar, A.I. Martinez-Puchol, P. Jares, S. Marín-Liébana, A. Magro, J.A. Puig-Butille, L. Palomar, E. Sanfeliu, M.T. Martinez, M.V. Losada, C. Hernando, B. Adamo, V. Iranzo, T. Pascual, A. Pouptsis, F. Schettini, A. Santaballa, B. Conte, M.D. Torregrosa, F. Brasó-Maristany, B. Walbaum, R. Gómez-Bravo, O. Burgués, I.G. Fructuoso, I. Garrido-Cano, E. Seguí, L. Paré, M. Muñoz, E. Carcelero, J. Sànchez, P. Villagrasa-González, W. Buckingham, A. Prat, G. Villacampa, N. Chic, P. Rivera, A. Rezqallah, C. Saura, S. Escrivà, B. Bermejo, A. Lluch, A. Llombart, J.M. Cejalvo
• A real-world analysis showing that HER2DX reflects both tumor and immune biology in daily care, and that no single pathological or immune variable can capture the same complexity on its own.
Title: Associations of the HER2DX Genomic Test with Biological and Pathological Features in HER2-positive Breast Cancer
Authors: Esther Sanfeliu, Anabel Martínez-Romero, Mercedes Marín-Aguilera, Sandra Cobo, Blanca González-Farré, Eva Hernandez-Illan, Pedro Jares, Joan-Anton Antón Puig-Butillé, Montserrat Muñoz, Raquel Gómez-Bravo, Marta Tapia, Cristina Tebar, Cristina Saura, Santiago Escribà, Jesús Soberino, Javier Cortés, Serafin Morales, Kepa Amillano, Laia Paré, Patricia Villagrasa, Wesley Buckingham, Francisco Pardo, Joel S. Parker, Fara Brasó-Maristany, Eva Ciruelos, Rodrigo Sánchez-Bayona, Olga Martinez-Sáez, Juan Miguel Cejalvo, Aleix Prat
• Specific analyses in populations that are often under-studied, such as older patients and inflammatory breast cancer.
Title: HER2DX in older patients with HER2-positive early breast cancer: extended follow-up from the RESPECT trial of trastuzumab ± chemotherapy
Authors: Kazuki Nozawa, Masataka Sawaki, Yukari Uemura, Michiko Tsuneizumi, Toshimi Takano, Naomi Gondo, Fumikata Hara, Michiko Harao, Tatsuya Toyama, Naruto Taira, Ana Vivancos, Charles M. Perou, Esther Sanfeliu, Fara Brasó-Maristany, Joel S. Parker, Wesley Buckingham, Laia Paré, Guillermo Villacampa, Mercedes Marín-Aguilera, Patricia Villagrasa, Aleix Prat, Hiroji Iwata
Title: HER2DX in HER2-positive inflammatory breast cancer: correlative insights and comparative analysis with noninflammatory breast cancers☆
Authors: F. Lynce, O. Martínez-Sáez, B. Walbaum, F. Brasó-Maristany, A.G. Waks, P. Villagrasa, G. Villacampa Javierre, E. Sanfeliu, P. Galván, L. Paré, L.M. Anderson, C.M. Perou, J.S. Parker, A. Vivancos, M.K. DiLullo, S. Pernas, E.P. Winer, B. Overmoyer, E.A. Mittendorf, C. Bueno-Muiño, M. Martín, A. Prat, S.M. Tolaney
• Extension of the HER2DX biology through the ERBB2 mRNA score in metastatic HER2-positive breast cancer.
Title: HER2DX ERBB2 mRNA score in first-line advanced HER2-positive breast cancer treated with chemotherapy, trastuzumab, and pertuzumab
Authors: Rodrigo Sánchez-Bayona, Olga Martínez-Sáez, Denys Romero-Romero, Elia Seguí, Esther Carcelero, Pablo Tolosa, Jesús Soberino, Manuel Alva, Tomás Pascual, Laura Lema, Isabel Garcia-Fructuoso, Maria Angeles Cobos-Fernandez, Maria Rey, Luis Manso, Angela Aguirre, Ainhoa Madariaga, Valeria Sirenko, Cristina González-Deza, Paula Blasco, Astrid Mayhua, Oleguer Castillo, Patricia Galván, Esther Sanfeliu, Guillermo Villacampa, Wesley Buckingham, Mercedes Marín-Aguilera, Laia Paré, Patricia Villagrasa, Charles M. Perou, Julia Maues, Fara Brasó-Maristany, Eva Ciruelos, Aleix Prat
• And finally, a study linking B-cell/plasma-cell infiltration and tertiary lymphoid structures, the immune axis embedded within HER2DX, to long-term recurrence-free “longevity” in breast cancer.
Title: Linking tumor immune infiltration to enhanced longevity in recurrence-free breast cancer
Authors: L. Angelats, L. Paré, C. Rubio-Perez, E. Sanfeliu, A. González, E. Seguí, G. Villacampa, M. Marín-Aguilera, S. Pernas, B. Conte, V. Albarrán-Fernández, O. Martínez-Sáez, Á. Aguirre, P. Galván, A. Fernandez-Martinez, S. Cobo, M. Rey, A. Martínez-Romero, B. Walbaum, F. Schettini, M. Vidal, W. Buckingham, M. Muñoz, B. Adamo, Y. Agrawal, S. Guedan, T. Pascual, J. Agudo, M. Grzelak, N. Borcherding, H. Heyn, A. Vivancos, J.S. Parker, P. Villagrasa, C.M. Perou, A. Prat, F. Brasó-Maristany
We also presented 2 oral communications from the EA1181CompassHER2pCR trial led by ECOG-ACRIN Cancer Research Group National Cancer Institute (NCI):
• At ASCO25, HER2DX pCR score predicted pCR independently of clinical–pathological variables.
• At SABCS25, HER2DX pCR score outperformed TILs for predicting pCR.
For me, the main takeaway is that useful biomarkers come from repeatedly confronting biology with clinical reality, in different contexts, over time.
The choice now sits with payers, guideline committees, physicians, and patients: either we integrate well-validated decision-support biomarkers, or we accept practicing precision oncology with unnecessary uncertainty.
Very grateful to all the collaborators, clinicians, and, above all, the patients who made this possible.”
More posts featuring Aleix Prat on OncoDaily.