Johan Hartman
About me
Professor (full) and research group leader at Karolinska Institutet.
Senior consultant and head of breast pathology program at the dept of pathology and cancerdiagnostics, Karolinska University Hospital and Södersjukhuset.
Scientific director for the Swedish Society for Pathology and former head of the expert group in breast pathology (KVAST). Scientific advisor to Socialstyrelsen. Co-founder of Stratipath, a Karolinska Insitutet-spinoff company.
Research
The main research focus of Dr Hartmans lab is breast cancer therapy prediction for individualised cancer therapy. This includes digital image analysis in histopathology and computer-aided diagnosis, cancer genomics/transcriptomics and patient derived tumor cell models. The team is also providing core center pathology service to several clincal trials. Dr Hartman has published > 150 research articles including >50 in high-impact journals (Cell, Science, PNAS etc) and cited > 12.000 times.
Teaching
Past main-supervisor for eight PhD-students, ongoing main-supervisor for three PhD-students.
Lecturer at Karolinska Institutet (annual courses for medical students, biomedicine students and PhD-students).
Articles
- Journal article: NPJ BREAST CANCER. 2026;12(1):113Schagerholm Stanev C; Robertson S; Toosi H; Sifakis EG; Lagergren J; Hartman J
- Article: BREAST CANCER RESEARCH. 2026;28(1):139Acs B; Liu X; Gkekos L; Karlsson E; Johansson ALV; Karlsson P; Andersson A; Valachis A; Fredriksson I; Foukakis T; Hartman J
- Article: VIRCHOWS ARCHIV. 2026;489(2):485-493Rask G; Olofsson H; Bauer A; Boden A; van Brakel J; Colon-Cervantes E; Ehinger A; Kovacs A; Rundgren-Sellei A; Hartman J; Agren J; Darai-Ramqvist E; Andersson C; Gustafsson CK; Acs B
- Journal article: NATURE COMMUNICATIONS. 2026;17(1):7410Pan Y; Pei S; Liang H; Westberg K; Nitschke L; Chen X; Yu Y; He N; Lin Q; Lei L; Gistera A; Hartman J; Ravetch JV; Mak TW; McGaha TL; Karlsson MCI
- Article: PATHOLOGY RESEARCH AND PRACTICE. 2026;283:156493Gebremariam TY; Boissin C; Jiffar AD; Sun W; Sori M; Hjelm TE; Assefa M; Anberber E; Bauer M; Ayele BG; Hartman J; Lofgren J; Rantalainen M; Ashenafi S
- Journal article: PATHOLOGY RESEARCH AND PRACTICE. 2026;283:156493Gebremariam TY; Boissin C; Jiffar AD; Sun W; Sori M; Ekdahl Hjelm T; Assefa M; Anberber E; Bauer M; Ayele BG; Hartman J; Löfgren J; Rantalainen M; Ashenafi S
- Journal article: JOURNAL OF CLINICAL ONCOLOGY. 2026;44(16_SUPPL):555Hartman J; Gray RJ; Rantalainen M; Robertson S; Broeckx G; Desmedt C; Lazar AJ; Badve SS; Loi S; Sparano JA; Salgado R
- Article: JOURNAL OF NUCLEAR MEDICINE. 2026;67(5):681-686Nijveldt JJ; Af Burén S; Tran TA; Jussing E; Nilsson JN; Kistner A; Axelsson R; Bergh J; Hartman J; Tzortzakakis A; Altena R
- Article: VIRCHOWS ARCHIV. 2026;:1-13Rasic D; Stovgaard EIS; Jylling AMB; Hoang T; le Fevre T; Salgado R; Hartman J; Rantalainen M; Laenkholm A-V
- Article: NATURE COMMUNICATIONS. 2026;17(1):3403Matikas A; Tzoras E; Sarafidis M; Sifakis EG; Bjohle J; Barnekow E; Margolin S; Isaksson-Friman E; Kessler LE; Zouzos A; Johansson H; Hellstrom M; Agartz S; Gryback P; Salgkamis D; Zerdes I; Wang K; Hartman J; Acs B; Sun W; Boyaci C; Villacampa G; Pascual T; Gavila J; Prat A; Perou C; Brandberg Y; Bergh J; Hatschek T; Foukakis T
- Journal article: CLINICAL CANCER RESEARCH. 2026;32(4_Supplement):ps2-08-26-ps2-08-26Zerdes I; Papakonstantinou A; Acs B; Tsiknakis N; Steen S; Karlsson E; Liu X; Wang K; Agartz S; Manikis G; Bergh J; Hartman J; Foukakis T
- Journal article: CLINICAL CANCER RESEARCH. 2026;32(4_Supplement):ps3-06-04-ps3-06-04Boissin C; Hartman J; Rantalainen M
- Journal article: CLINICAL CANCER RESEARCH. 2026;32(4_Supplement):ps2-08-01-ps2-08-01Salgkamis D; Sarafidis M; Sifakis E; Zerdes I; Agartz S; Hartman J; Hellström M; Foukakis T; Bergh J; Matikas A
- Article: INTERNATIONAL JOURNAL OF CANCER. 2026;158(4):1106-1115Danielsson O; Dar H; Perez-Tenorio G; Nordenskjold A; Yau C; Benz CC; Esserman LJ; Nordenskjold B; Stal O; Fornander T; Hartman J; Tobin NP; Johansson A; Lindstrom LS
- Article: BREAST. 2026;85:104671Pouplier SS; Sharma A; Ruusuvuori P; Hartman J; Jensen M-B; Ejlertsen B; Rantalainen M; Laenkholm A-V
- Article: BIOCHEMICAL PHARMACOLOGY. 2026;244:117625Krahulcova L; Lindell E; Lu X; Monsalve JJC; Haraldsson M; Li Z; Chen X; Aune G; Zhao M; Tong L; Hartman J; Lehti K; Swartling FJ; Chen X; Sjoblom T; Zhang X
- Article: CANCER MEDICINE. 2026;15(2):e71570Bergman M; Schiza A; Boyaci C; Acs B; Matikas A; Hartman J; Valachis A
- Article: LANCET REGIONAL HEALTH-EUROPE. 2025;59:101471Liu X; Binicy B; Acs B; Bergman LE; Loibl S; Gnant M; Untch M; Valachis A; Bergh J; Hartman J; Foukakis T; Matikas A
- Article: BREAST CANCER RESEARCH. 2025;27(1):213Steen S; Karlsson E; Bjornheden I; Rask G; Thurfjell V; Nobin H; Kolodziej B; Boden A; Bauer A; Einefors R; Nilsson P; Zerdes I; Papakonstantinou A; Foukakis T; Fredriksson I; Rantalainen M; Colon-Cervantes E; Kovacs A; Acs B; Hartman J
- Article: BIOMEDICINES. 2025;13(12):2897Zouzos A; Fredriksson I; Foukakis T; Hartman J; Strand F
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All other publications
- Preprint: BIORXIV. 2026Kolbeinsdóttir S; Zachariadis V; Yang M; Broeils L; Sommerauer C; Cheng H; Chen X; Lin Y; Falco MM; Hynninen J; Hautaniemi S; Sun Y; Lohi O; Heinäniemi M; Brage SE; Sarhan D; Herold N; Hartman J; Helgadóttir H; de Flon FH; Vähärautio A; Enge M
- Conference publication: CLINICAL CANCER RESEARCH. 2026;32(4_Supplement):ps3-11-24-ps3-11-24q. yang; Rönnlund C; Stanev CS; Chen X; Foukakis T; Wang K; Fredriksson I; Stephanie R; Sifakis EG; Hartman J
- Conference publication: CLINICAL CANCER RESEARCH. 2026;32(4_Supplement):ps3-07-29-ps3-07-29q. yang; Chen X; Hartman J; Acs B
- Conference publication: CLINICAL CANCER RESEARCH. 2026;32Boissin C; Hartman J; Rantalainen M
- Conference publication: CLINICAL CANCER RESEARCH. 2026;32Yang Q; Ronnlund C; Stanev CS; Chen X; Foukakis T; Wang K; Fredriksson I; Stephanie R; Sifakis EG; Hartman J
- Conference publication: CLINICAL CANCER RESEARCH. 2026;32Yang Q; Chen X; Hartman J; Acs B
- Conference publication: CLINICAL CANCER RESEARCH. 2026;32Salgkamis D; Sarafidis M; Sifakis E; Zerdes I; Agartz S; Hartman J; Hellstrom M; Foukakis T; Bergh J; Matikas A
- Conference publication: CLINICAL CANCER RESEARCH. 2026;32Zerdes I; Papakonstantinou A; Acs B; Tsiknakis N; Steen S; Karlsson E; Wang K; Agartz S; Manikis G; Bergh J; Hartman J; Foukakis T
- Preprint: BIORXIV. 2026Gao C; Martino M; Chaurasiya A; Casagrande FB; Lim JP; van Ekelenburg YS; Feng W; Liu Y; Scholz B; Mishra P; Thippana M; Torkornoo D; Chau PK; Khan R; Tannaes TM; Tzelepis I; Chacoua I; Geyer N; Meltzer S; Ree AH; Gerling M; Hartman J; Kiani N; Ohlsson R; Göndör A
- Other: AMERICAN ASSOCIATION FOR CANCER RESEARCH (AACR). 2025Matikas A; Johansson H; Grybäck P; Bjöhle J; Acs B; Boyaci C; Lekberg T; Fredholm H; Elinder E; Margolin S; Isaksson-Friman E; Bosch A; Lindman H; Adra J; Andersson A; Agartz S; Hellström M; Zerdes I; Hartman J; Bergh J; Hatschek T; Foukakis T
- Other: AMERICAN ASSOCIATION FOR CANCER RESEARCH (AACR). 2025Matikas A; Johansson H; Grybäck P; Bjöhle J; Acs B; Boyaci C; Lekberg T; Fredholm H; Elinder E; Margolin S; Isaksson-Friman E; Bosch A; Lindman H; Adra J; Andersson A; Agartz S; Hellström M; Zerdes I; Hartman J; Bergh J; Hatschek T; Foukakis T
- Other: AMERICAN ASSOCIATION FOR CANCER RESEARCH (AACR). 2025Matikas A; Johansson H; Grybäck P; Bjöhle J; Acs B; Boyaci C; Lekberg T; Fredholm H; Elinder E; Margolin S; Isaksson-Friman E; Bosch A; Lindman H; Adra J; Andersson A; Agartz S; Hellström M; Zerdes I; Hartman J; Bergh J; Hatschek T; Foukakis T
- Other: AMERICAN ASSOCIATION FOR CANCER RESEARCH (AACR). 2025Matikas A; Johansson H; Grybäck P; Bjöhle J; Acs B; Boyaci C; Lekberg T; Fredholm H; Elinder E; Margolin S; Isaksson-Friman E; Bosch A; Lindman H; Adra J; Andersson A; Agartz S; Hellström M; Zerdes I; Hartman J; Bergh J; Hatschek T; Foukakis T
- Other: AMERICAN ASSOCIATION FOR CANCER RESEARCH (AACR). 2025Matikas A; Johansson H; Grybäck P; Bjöhle J; Acs B; Boyaci C; Lekberg T; Fredholm H; Elinder E; Margolin S; Isaksson-Friman E; Bosch A; Lindman H; Adra J; Andersson A; Agartz S; Hellström M; Zerdes I; Hartman J; Bergh J; Hatschek T; Foukakis T
- Other: AMERICAN ASSOCIATION FOR CANCER RESEARCH (AACR). 2025Matikas A; Johansson H; Grybäck P; Bjöhle J; Acs B; Boyaci C; Lekberg T; Fredholm H; Elinder E; Margolin S; Isaksson-Friman E; Bosch A; Lindman H; Adra J; Andersson A; Agartz S; Hellström M; Zerdes I; Hartman J; Bergh J; Hatschek T; Foukakis T
- Other: AMERICAN ASSOCIATION FOR CANCER RESEARCH (AACR). 2025Matikas A; Johansson H; Grybäck P; Bjöhle J; Acs B; Boyaci C; Lekberg T; Fredholm H; Elinder E; Margolin S; Isaksson-Friman E; Bosch A; Lindman H; Adra J; Andersson A; Agartz S; Hellström M; Zerdes I; Hartman J; Bergh J; Hatschek T; Foukakis T
- Other: AMERICAN ASSOCIATION FOR CANCER RESEARCH (AACR). 2025Matikas A; Johansson H; Grybäck P; Bjöhle J; Acs B; Boyaci C; Lekberg T; Fredholm H; Elinder E; Margolin S; Isaksson-Friman E; Bosch A; Lindman H; Adra J; Andersson A; Agartz S; Hellström M; Zerdes I; Hartman J; Bergh J; Hatschek T; Foukakis T
- Preprint: PREPRINTS.ORG. 2025Zouzos A; Fredriksson I; Foukakis T; Hartman J; Strand F
- Dataset: KI DATA REPOSITORY. 2025Hartman J; Schagerholm Stanev C
- Dataset: KI DATA REPOSITORY. 2025Llorens-Bobadilla E; Zamboni M; Chen X; Hartman J
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Grants
- Swedish Research Council1 January 2026 - 31 December 2028Cancer remains a leading global cause of death, with rising incidence placing increasing strain on healthcare systems. Breast cancer, the most common cancer in women, is heterogeneous with variability in patient outcomes. To optimize breast cancer care, accessible and cost-effective precision diagnostic solutions are needed to provide clinicians with reliable decision support for treatment allocation. AI-driven approaches for treatment response prediction, prognostic modeling, and phenotyping can enhance patient stratification by identifying subgroups likely to benefit from specific therapies or requiring intensified treatment.Current precision diagnostics relies primarily on molecular diagnostics, which remain expensive and inaccessible to most cancer patients worldwide. AI-based diagnostic solutions for analysis of readily available data modalities offer a potential route towards sustainable precision medicine.This project extends our ongoing research in AI-driven precision pathology, leveraging large studies and deep learning to analyse routine H&E stained histopathology images that provide a rich and underutilized data source for cost-effective precision diagnostics with low implementation barriers. This research aims to advance deep learning methodology for histopathology, develop and validate breast cancer precision diagnostic models, and contribute to increased access to precision diagnostics and improved patient outcomes.
- Swedish Research Council1 December 2024 - 30 November 2028Breast cancer (BC) remains a global health challenge, with 7.8 million new cases annually. Despite treatment and screening advances that have gradually improved outcomes since the 1970s, many patients still do not survive their dissease, creating an urgent need for precision diagnostics to identify high-risk individuals and predict therapeutic responses. The Consortium for AI in Registry-Based Image Epidemiology Research in Breast Cancer (CARE-B) addresses this by combining registry data, histopathology images, and AI to improve BC characterization.CARE-B will establish an internationally unique large (up to 30,000 patients), multimodal multi-site database integrating clinical data, whole slide images (WSIs), and molecular profiles from breast cancer cohorts in Sweden, Denmark, and Scotland. The consortium will develop scalable AI models for cost-effective precision diagnostics, focusing on deep phenotyping of BC subtypes based on routine H&E stained histopathology slides, characterise intra-tumor heterogeneity (ITH), predicting treatment responses and for prognostic stratification.CARE-B will foster collaboration, support junior researchers, and advance epidemiological research and clinical translation. By leveraging AI and registry data, CARE-B aims to significantly impact BC research and clinical diagnostics, creating a foundation for future advances in precision medicine, while also building a research environment that take health-registry research to the next level.
- Swedish Research Council1 January 2024 - 31 December 2027Most breast cancer patients are diagnosed with hormone-dependent (estrogen receptor-positive, ER+) breast cancer and endocrine treatment is standard of care. A unique feature of ER+ disease is that the risk to develop distant metastasis remains stable beyond 5-10 years after diagnosis, and half or more of all metastases will be diagnosed after this initial follow-up. The tumor biological factors underlying long-term risk are poorly understood, and it will remain a considerable clinical challenge in the foreseeable future. We will investigate the influence of standard clinical markers, their intra-tumor heterogeneity, and the heterogeneous ER+ tumor microenvironment, to identify tumor characteristics influencing long-term risk and benefit from endocrine treatment. Novel deep-learning methods will be used and in depth spatial analysis will enable understanding of tumor biology down to single-cell level. We will use unique and large clinical trials with patients randomized to endocrine treatment versus not with complete long-term follow-up. The distinction of long-term risk is essential, since accurate risk prediction allows for individualized treatment, decreases anxiety, and supports aggressive treatment for patients at high risk of fatal disease. Our study has the potential to answer vital questions about the influence of the tumor microenvironment and intra-tumor heterogeneity for long-term risk in ER+ breast cancer, helped by the interdisciplinary expertise in our team.
- Swedish Research Council1 January 2023 - 31 December 2025
- Swedish Research Council1 January 2022 - 31 December 2025
- Swedish Research Council1 January 2021 - 31 December 2023
- Swedish Research Council1 December 2020 - 31 December 2024
- Swedish Research Council1 January 2019 - 31 December 2022
- Swedish Research Council1 January 2019 - 31 March 2021
- Swedish Research Council1 January 2019 - 31 December 2021
Employments
- Professor/Senior Physician, Tumor Pathology, Department of Oncology-Pathology, Karolinska Institutet, 2023-
- Professor/Assistant Senior Physician, Department of Oncology-Pathology, Karolinska Institutet, 2021-2023
Degrees and Education
- Docent, Karolinska Institutet, 2015
- Degree Of Doctor Of Philosophy, Department of Biosciences and Nutrition, Karolinska Institutet, 2008
- University Medical Degree, Karolinska Institutet, 2008
Distinction and awards
- The award for Innovation, Karolinska Institutet, 2023
- Athenapriset, Vetenskapsrådet/LIF/Dagens Medicin, 2022
- Sophiastipendiet, Sophiahemmet Hospital, 2020
- Clinical Investigator award, Swedish Cancer Society, 2016
- Alvarengas award, Swedish Society of Medicine, 2013
- Asklepios award, Swedish Society of Medicine, 2009
- The McKinsey Award, 2007
- The Anders Wall award, 2006