Líffræðifélag Íslands - biologia.is
Líffræðiráðstefnan 2019
Erindi/veggspjald / Talk/poster E13
Höfundar / Authors: Olafsdottir EJ (1), Aittomäki K (2), Barkardottir RB (3,4), Blomqvist C (5), Borg A (6), Ejlertsen B (7,8), Gerdes AM (9), Heeholm Sønderstrup IM (10), Hovig E (11), Jensen M-B (7), Johannsson OT (12), Jonasson JG (13,14), Lænkholm A-V (15), Loman N (6), Nevanlinna H(16), Nilsson M (6,) Olafsdottir GH (1), Rossing M (17), Sigurdsson S (18), Narod SA (19), Tryggvadottir L (1,3)
Starfsvettvangur / Affiliations: 1. Icelandic Cancer Registry, Icelandic Cancer Society, Reykjavik, Iceland; 2. Department of Clinical Genetics, Helsinki University Hospital and University of Helsinki; 3. Faculty of Medicine, BMC, Laeknagardur, University of Iceland, Reykjavik, Iceland; 4. Laboratory of Cell Biology, Department of Pathology, Landspitali University Hospital, Reykjavik, Iceland; 5. Department of Oncology, Helsinki University Hospital and University of Helsinki 6. Division of Oncology and Pathology, Department of Clinical Sciences, Lund University, Lund, Sweden; 7. Danish Breast Cancer Cooperative Group, Rigshospitalet, Copenhagen University Hospital, Copenhagen, Denmark; 8. Department of Clinical Oncology, Rigshospitalet, Copenhagen University Hospital, Copenhagen, Denmark; 9. Department of Clinical Genetics, Rigshospitalet, Copenhagen University Hospital, Copenhagen, Denmark; 10. Department of Surgical Pathology, Zealand University Hospital, Roskilde, Denmark; 11. Department of Tumor Biology, Institute for Cancer Research, Radium Hospital, Oslo University Hospital, Norway; 12. Department of Oncology, Landspitali University Hospital, Reykjavik, Iceland; 13. Faculty of Medicine, University of Iceland, Reykjavik, Iceland; 14. Department of Pathology, Landspitali University Hospital, Reykjavik, Iceland; 15. Department of Surgical Pathology, Zealand University Hospital, Slagelse, Denmark; 16. Department of Obstetrics and Gynecology, Helsinki University Hospital and University of Helsinki, Finland; 17. Center for Genomic Medicine, Rigshospitalet, Copenhagen University Hospital, Copenhagen, Denmark; 18. Cancer Research Laboratory, BMC, School of Health Sciences, University of Iceland, Reykjavik, Iceland; 19. Womens’ College Research Institute, University of Toronto, Toronto, ON, Canada
Kynnir / Presenter: Laufey Tryggvadóttir
Background: Women with a BRCA2 mutation have a high risk of breast cancer, which is typically
estrogen-receptor positive (ER+). Contrary to the well-known beneficial effects of an ER+ status on breast cancer survival, Icelandic BRCA2 mutation carriers have an increased risk of nodal invasion and death if their tumours are ER+. We sought to confirm this unexpected association in BRCA2 carrier cases from five Nordic countries.
Materials & methods: The total number of Nordic BRCA2 carriers was 671. Information on prognostic factors and treatment was retrieved from health records or by immunohistochemistry analyses of archived tissue specimens. Hazard ratios (HR) for various factors were estimated for breast cancer-specific survival using Cox regression.
Results: Comparing ER+ with ER- carriers, 58% vs. 34% had nodal invasion at diagnosis. and multivariate HR was 1.90 (95% CI 1.06-3.38, P=0.030) for premenopausal patients, but 0.54 (95% CI 0.28 to 1.04, P=0.067) for postmenopausal patients, P for interaction 0.069. Comparing oophorectomy with no oophorectomy HR=0.49 (95% CI 0.32-0.77, P=0.002), similar for pre- and postmenopausal cases. Hormone treatment was protective only among premenopausal patients (HR=0.48, 95% CI 0.30-0.77, P=0.002).
Conclusion: ER positive tumours predict a poor prognosis in premenopausal BRCA2 carriers. However, oophorectomy mitigates this effect. The results have biological implications in addition to highlighting the value of a breast cancer patient knowing her BRCA2 carrier status at the time treatment is planned.