Clinical trial · Observational
Finasteride (MK-0906) and Male Breast Cancer - A Register-Based Nested Case-Control Study (MK-0906-162/2003.021).
Finasteride and Male Breast Cancer - A Register-Based Nested Case-Control Study in Denmark, Finland, Norway, and Sweden
- Source
- ClinicalTrials.gov
- Retrieved
- Sep 8, 2026
- Layer
- normalized (units and labels harmonized; values unchanged)
- Run
- ING-CLINICALTRIALS-20260908-000001
Summary
Brief summary (as posted)
The objective of this study is to investigate the potential association between finasteride (MK-0906) exposure and the development of breast cancer in men residing in Denmark, Sweden, Finland, and Norway from data in national registries. The primary hypothesis of this study is that the previously reported increased incidence of male breast cancer among finasteride users is explained by confounding factors.
Conditions
Conditions (1)
Free-text conditions as registered, with the CancerIndex entity they were reconciled to and the match type.
| Condition (as posted) | Mapped entity | Match | Confidence |
|---|---|---|---|
| Male Breast Cancer | Male Breast Carcinoma | ALIAS | 0.90 |
Interventions
Interventions (0)
Data not yet available
Design
Arms and outcomes
Arms (4)
- label
- Male Finasteride Users
- description
- Male finasteride users aged 35 years and above in the registries of Denmark (1995-2013), Finland (1994-2013), Norway (2008-2013), and Sweden (2005-2013).
- label
- Male Finasteride Non-users
- description
- Country-matched male finasteride non-users aged 35 years and above in the registries of Denmark (1995-2013), Finland (1994-2013), Norway (2008-2013), and Sweden (2005-2013).
- label
- Men with Breast Cancer
- description
- Breast cancer cases among men aged 35 years and above in the registries of Denmark (1995-2013), Finland (1994-2013), Norway (2008-2013), and Sweden (2005-2013).
- label
- Men without Breast Cancer
- description
- Country- and age-matched controls: men without breast cancer aged 35 years and above in the registries of Denmark (1995-2013), Finland (1994-2013), Norway (2008-2013), and Sweden (2005-2013).
Primary outcomes (4)
Eligibility
Eligibility (as posted)
- Sex
- Male
- Minimum age
- 35 Years
Show eligibility criteria text
Inclusion Criteria: * Participant's study medical information available in population-based health and medical registries, prescription registries, and mortality registries in Denmark, Finland, Norway, or Sweden within the observation period of 1995 to 2013 * Male with breast cancer with medical information in one of the 4 country-specific registries in this study OR country- and age-matched control men without breast cancer and with medical information in one of the 4 country-specific registries * Study participant's exposure to finasteride is available Exclusion Criteria: For country- and age-matched control men without breast cancer * Previous cancer diagnosis or treatment for cancer except non-melanoma skin cancer * Previous prostatectomy * Finasteride or dutasteride use (dutasteride is a drug in the same class as finasteride) within first 6 months of registration in the prescription registers (new user design).
References
Publications (1)
- RESULTMeijer M, Thygesen LC, Green A, Emneus M, Brasso K, Iversen P, Pukkala E, Bolin K, Stavem K, Ersboll AK. Finasteride treatment and male breast cancer: a register-based cohort study in four Nordic countries. Cancer Med. 2018 Jan;7(1):254-260. doi: 10.1002/cam4.1273. Epub 2017 Dec 13. PMID 29239131