Prof. Jonas Bergh

Prof. Jonas Bergh is a professor of oncology at Karolinska Institutet and a senior consultant in medical oncology at Karolinska University Hospital — Sweden's pre-eminent academic medical centre and one of Europe's foremost cancer treatment institutions. Over a career spanning more than 35 years, Prof. Bergh has established himself as one of Europe's most influential breast cancer oncologists, combining exceptional clinical expertise with a prolific research programme that has shaped the global management of breast cancer.

His clinical practice encompasses the full breadth of breast cancer management — from early-stage disease where curative intent drives treatment to the complex, multi-line management of metastatic breast cancer. He has been at the forefront of the HER2-positive breast cancer revolution, having been a key investigator in the pivotal clinical trials that established trastuzumab as standard adjuvant therapy and subsequently in trials examining pertuzumab and T-DM1. His participation in the FinnHer trial and the TEAM trial, among others, has contributed directly to the therapeutic options now available to HER2-positive breast cancer patients worldwide.

Beyond his contributions to HER2-targeted therapy, Prof. Bergh has been a consistent advocate for dose-dense and dose-intensified chemotherapy regimens in high-risk early breast cancer. His research in this area has challenged dogma about the optimal delivery of cytotoxic treatment and provided evidence-based rationale for more intensive treatment approaches in selected patients.

As a faculty member at the San Antonio Breast Cancer Symposium and a frequent invited speaker at ESMO and ASCO meetings, Prof. Bergh occupies a prominent place in the international breast cancer community, regularly presenting his own data and offering expert commentary on the latest advances in the field.

Prof. Bergh completed his medical degree at a Swedish medical faculty before undertaking specialty training in oncology within the Swedish hospital and university training system. He was awarded his PhD for translational research examining molecular determinants of breast cancer prognosis and response to chemotherapy — work that reflected his early commitment to bridging laboratory science and clinical oncology.

He pursued advanced subspecialty training in medical oncology with a focus on breast cancer, including international research exposure at leading cancer centres in Europe and North America. This training equipped him with both clinical skills in systemic therapy administration and the scientific tools to develop and evaluate novel therapeutic hypotheses through clinical trials.

Prof. Bergh holds the Fellowship of the European Society for Medical Oncology (FESMO), recognising his standing as a European oncology leader. He holds a full professorship at Karolinska Institutet, where he leads a research group focused on translational breast cancer biology, and he supervises doctoral and postdoctoral researchers contributing to the next generation of breast cancer science in Sweden and internationally.

Prof. Bergh's primary clinical focus is the systemic treatment of breast cancer — both curative and palliative. He is an authority on the selection and sequencing of systemic therapies across all breast cancer subtypes, with particular depth of expertise in HER2-positive disease. He manages the full therapeutic sequence for HER2-positive patients: neoadjuvant dual anti-HER2 blockade (pertuzumab plus trastuzumab with chemotherapy), assessment of pathological complete response, adjuvant T-DM1 for residual disease, and metastatic disease management including trastuzumab deruxtecan.

In hormone receptor-positive breast cancer, he expertly deploys endocrine therapy combined with CDK4/6 inhibitors, mTOR inhibitors, and PI3K inhibitors based on molecular tumour profiling. For triple-negative breast cancer patients, he incorporates immunotherapy with pembrolizumab, olaparib for BRCA-mutated tumours, and sacituzumab govitecan.

Prof. Bergh is also expert in neoadjuvant therapy strategies — using pre-operative systemic treatment to downstage tumours for breast-conserving surgery and to assess biological response in vivo. He participates in multidisciplinary tumour boards and integrates molecular profiling results, including gene expression assays (Oncotype DX, Prosigna), into treatment planning for his patients.

Prof. Bergh has authored over 400 peer-reviewed publications in journals including the Lancet, New England Journal of Medicine, Journal of Clinical Oncology (JCO), Annals of Oncology, and Clinical Cancer Research. His work spans basic science, translational biology, and clinical trial outcomes, reflecting his career-long commitment to moving discoveries from bench to bedside.

Among his most significant contributions, his co-investigator role in the FinnHer trial — one of the first studies to establish one year of trastuzumab as the optimal duration in HER2-positive early breast cancer adjuvant treatment — has had lasting clinical impact. The TEAM trial, examining tamoxifen versus exemestane in hormone receptor-positive postmenopausal breast cancer, is another major contribution to the endocrine therapy landscape.

His research on dose-dense and dose-intensified chemotherapy, including high-dose chemotherapy with peripheral blood stem cell support in high-risk early breast cancer, addressed fundamental questions about cytotoxic drug delivery that remain relevant to current chemotherapy scheduling debates. His translational research examining predictive biomarkers of chemotherapy response and resistance has also contributed to the growing precision oncology toolkit in breast cancer.

Prof. Bergh consults in Swedish and English and welcomes referrals from international patients seeking expert opinion on breast cancer diagnosis, treatment planning, and second opinions. Karolinska University Hospital is internationally accredited and experienced in providing care to patients from across Europe and beyond, with dedicated international patient coordination services.

EU/EEA patients may access care at Karolinska University Hospital under European health insurance arrangements. Non-EU patients are seen on a private basis with full administrative support. Telemedicine second-opinion consultations are available, enabling patients and their oncologists in other countries to access Prof. Bergh's expertise for treatment planning, molecular profiling interpretation, and guidance on trial eligibility.

For patients with HER2-positive or high-risk early breast cancer considering aggressive systemic treatment approaches, consultation with Prof. Bergh's team — which can be initiated remotely before any decision to travel — is particularly valuable. The Karolinska breast oncology team works in close collaboration with breast surgery, pathology, genetics, and radiation oncology.

Prof. Bergh has been the recipient of the King Gustaf V Jubilee Fund award, one of Sweden's most prestigious scientific research grants, in recognition of his contributions to cancer research. The Swedish Cancer Society has awarded him its Research Prize for sustained excellence in translational breast cancer science. Karolinska Institutet has recognised his contributions with its Research Award, presented to faculty members whose work has achieved significant national and international scientific impact.

He holds the Fellowship of the European Society for Medical Oncology (FESMO) and has served on ESMO scientific committees and guideline working groups. Prof. Bergh is a regular faculty member at the San Antonio Breast Cancer Symposium, one of the world's most important annual breast cancer meetings, where he presents original data and chairs scientific sessions. He has delivered named lectureships at Swedish, Nordic, and international oncology congresses.