New Danish study below.
I have been following the vasectomy-PCa link for 15 years. At diagnosis my vasectomy was already 25 years in the past.
It seems to me that the cancer link to vasectomy has been deemed to be unacceptable. What would happen if men throughout the world refused vasectomies?
One expects number of sexual partners & STDs to be PCa risk factors, but length of marriage is also a risk factor. A long-term sexual relationship with one partner with no STDs is a risk factor. It seemed to me plausible that a vasectomy would therefore increase risk, since one reason for a vasectomy is to no longer have to use condoms.
Anyway, here is a new study that stirs things up yet again:
"Overall, 26,238 cases of prostate cancer occurred among 2,150,162 Danish men during 53.4 million person-years of follow-up. Overall, vasectomized men had an increased risk of prostate cancer compared with non-vasectomized men (relative risk 1.15 ...). The increased risk of prostate cancer following vasectomy persisted for at least 30 years after the procedure and was observed regardless of age at vasectomy and cancer stage at diagnosis. Adjustment for the number of visits to doctor and socioeconomic factors did not explain the association."
Get ready for the pro-vasectomy crowd to jump all over the findings.
-Patrick
[1] academic.oup.com/jnci/advan...
Vasectomy and prostate cancer risk: a 38-year nationwide cohort study
Anders Husby Jan Wohlfahrt Mads Melbye
JNCI: Journal of the National Cancer Institute, djz099, doi.org/10.1093/jnci/djz099
Published: 23 May 2019
Abstract
Background
A man’s risk of prostate cancer has been linked to his prior reproductive history, with low sperm quality, low ejaculation frequency, and a low number of offspring being associated with increased prostate cancer risk. It is however highly controversial whether vasectomy, a common sterilization procedure for men, influences prostate cancer risk.
Methods
We established a cohort of all Danish men (born from 1937) and linked information on vasectomy, doctor visits, socioeconomic factors and cancer from nationwide registries using unique personal identification numbers. Incidence risk ratios for prostate cancer by time since vasectomy and age at vasectomy during the follow-up were estimated using log-linear Poisson regression.
Results
Overall, 26,238 cases of prostate cancer occurred among 2,150,162 Danish men during 53.4 million person-years of follow-up. Overall, vasectomized men had an increased risk of prostate cancer compared with non-vasectomized men (relative risk 1.15; 95% CI, 1.10 to 1.20). The increased risk of prostate cancer following vasectomy persisted for at least 30 years after the procedure and was observed regardless of age at vasectomy and cancer stage at diagnosis. Adjustment for the number of visits to doctor and socioeconomic factors did not explain the association.
Conclusions
Vasectomy is associated with a statistically significant increased long-term risk of prostate cancer. The absolute increased risk following vasectomy is nevertheless small, but our finding supports a relationship between reproductive factors and prostate cancer risk.
