Hair Loss/Finasteride , AGA
QUESTION: Hello Dr Peter, I hope you are fine.
Sir if a male have male breast cancer gene, and if he takes Finasteride , so is it possible that the gene could be activated by Finasteride and in turn causes Breast cancer?
ANSWER: I would not expect that to happen. That has never been proven to have happened.
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QUESTION: But Sir there have been 50 cases worldwide where patients took Finasteride and then got male breast cancer?
How many men have take finasteride and not gotten breast cancer? There were at least 50 men who had hot peppers in their dinner last night and died of a heart attack that night. Are we to assume a causal relationship?
The study done which suggest there is a link states more definitive studies need to be done. In the older age group who took the 5 mg finasteride the incidence of breast cancer is greater and it may turn out that those who sought medical treatment for their enlarged prostates were more at risk than those who did not. The incidence is too small to be certain and it is not a proven correlation as yet.
A study done two years ago disproved the earlier study done in 2010 which thought there may be a connection.
Read the last line of this abstract report:
J Urol. 2013 Nov;190(5):1811-4. doi: 10.1016/j.juro.2013.04.132. Epub 2013 May 9.
Male breast cancer and 5α-reductase inhibitors finasteride and dutasteride.
Bird ST1, Brophy JM, Hartzema AG, Delaney JA, Etminan M.
We examined the association between 5α-reductase inhibitors and male breast cancer.
MATERIALS AND METHODS:
Study participants were men 40 to 85 years old, with prescription and medical coverage, enrolled in the United States IMS LifeLinkô Health Plan claims database between 2001 and 2009. Cases required a primary breast cancer diagnosis (ICD-9-CM 175.x) on 2 different dates and a procedural code for mastectomy or lumpectomy/partial mastectomy with evidence of continuous care (radiation/chemotherapy or diagnoses in 2 or more months). Eligible controls were within 5 years in age and had duration of prior health care enrollment within 6 weeks. Risk set sampling selected 20 controls per case. We assessed the rate ratio for male breast cancer with 5α-reductase inhibitor exposure using conditional logistic regression. Analyses were stratified by duration of health care enrollment before diagnosis (1 year or more, 2 years or more and 3 years or more), each incremental 180 and 365 days of cumulative 5α-reductase inhibitor exposure, and period specific time frames before diagnosis (years 1, 2 and 3).
We identified 339 breast cancer cases matched to 6,780 controls. No statistically significant associations were observed between 5α-reductase inhibitors and breast cancer regardless of exposure assessment before the index date (1 year or more-RR 0.70, 95% CI 0.34-1.45; 2 years or more-RR 0.59, 95% CI 0.24-1.48; or 3 years or more-RR 0.75, 95% CI 0.27-2.10). Each subsequent 180 days (RR 1.02, 95% CI 0.67-1.53) and 365 days (RR 1.03, 95% CI 0.45-2.37) of cumulative 5α-reductase inhibitor therapy and period specific rate ratios also showed null associations.
The lack of an association in our study suggests that the development of breast cancer should not influence the prescribing of 5α-reductase inhibitor therapy.