No link between short-term testosterone use and prostate cancer, study says
Testosterone therapy does not cause adverse effects on the prostate in older men with hypogonadism, commonly known as low testosterone or low T, according to a clinical trial presented today at a national urology meeting in Atlanta. The study, which focused on direct measurement of testosterone in prostate tissues, carries important implications for the millions of men with low testosterone, who may benefit from testosterone replacement therapy. Results from the study were presented in two abstracts at the American Urological Association annual meeting.
"We found no evidence that testosterone replacement therapy negatively affects the prostate or its tissues in hypogonadal men following six months of treatment," said Dr. Leonard Marks, co-investigator, Clinical Associate Professor in the Department of Surgery/Urology at the UCLA School of Medicine and founding medical director of Urological Sciences Research Foundation (USRF). "Patients should be comforted by these results, but large-scale, long-term trials are still needed."
Testosterone is a hormone involved in regulating prostate growth, both benign and malignant. When testosterone is boosted, the effect on the prostate is a main concern in older men. However, this study showed that when serum testosterone levels are increased to the mid-normal level, the prostate effects are minimal, at 6-months.
In the randomized, placebo-controlled clinical trial, investigators examined the effects of testosterone (T) in 41 men, ages 50-75 years old with hypogonadism (ADAM score and morning T<300 ng/dL) for a 6-month period. Twenty-one men received testosterone intramuscular injections (150 mg every two weeks); 20 men received placebo. The study was powered to detect a 25% increase in dihydrotestosterone (DHT) in prostate tissue. The groups were comparable at baseline for age, serum T and DHT, Prostate-Specific Antigen (PSA), Prostate Volume (PV) and median prostate levels of T and DHT. Prostate biopsies were conducted at baseline and at 6-months.
No prostate tissue changes attributable to testosterone therapy were found in this trial. Despite marked increases in serum testosterone levels, prostate levels of T and DHT (the hormone that stimulates prostate gland growth) did not change from baseline at 6-months. PSA, PV, tissue biomarkers and indices for atrophy and inflammation also were unchanged after 6-months of treatment. Furthermore, gene expression was not altered, cell proliferation was not accelerated, and histologic cancers were not increased. The study also showed testosterone therapy created positive effects in bones and muscles.
"The prostate appears to be buffered against rather wide fluctuations in serum testosterone levels," said Dr. Marks. "Still, all hypogonadal men considering testosterone therapy, especially older men, must be monitored closely by their physicians prior to and throughout treatment."
Dr. Leonard Marks | EurekAlert!
The most recent press releases about innovation >>>
Die letzten 5 Focus-News des innovations-reports im Überblick:
An international team of scientists has proposed a new multi-disciplinary approach in which an array of new technologies will allow us to map biodiversity and the risks that wildlife is facing at the scale of whole landscapes. The findings are published in Nature Ecology and Evolution. This international research is led by the Kunming Institute of Zoology from China, University of East Anglia, University of Leicester and the Leibniz Institute for Zoo and Wildlife Research.
Using a combination of satellite and ground data, the team proposes that it is now possible to map biodiversity with an accuracy that has not been previously...
Heatwaves in the Arctic, longer periods of vegetation in Europe, severe floods in West Africa – starting in 2021, scientists want to explore the emissions of the greenhouse gas methane with the German-French satellite MERLIN. This is made possible by a new robust laser system of the Fraunhofer Institute for Laser Technology ILT in Aachen, which achieves unprecedented measurement accuracy.
Methane is primarily the result of the decomposition of organic matter. The gas has a 25 times greater warming potential than carbon dioxide, but is not as...
Hydrogen is regarded as the energy source of the future: It is produced with solar power and can be used to generate heat and electricity in fuel cells. Empa researchers have now succeeded in decoding the movement of hydrogen ions in crystals – a key step towards more efficient energy conversion in the hydrogen industry of tomorrow.
As charge carriers, electrons and ions play the leading role in electrochemical energy storage devices and converters such as batteries and fuel cells. Proton...
Scientists from the Excellence Cluster Universe at the Ludwig-Maximilians-Universität Munich have establised "Cosmowebportal", a unique data centre for cosmological simulations located at the Leibniz Supercomputing Centre (LRZ) of the Bavarian Academy of Sciences. The complete results of a series of large hydrodynamical cosmological simulations are available, with data volumes typically exceeding several hundred terabytes. Scientists worldwide can interactively explore these complex simulations via a web interface and directly access the results.
With current telescopes, scientists can observe our Universe’s galaxies and galaxy clusters and their distribution along an invisible cosmic web. From the...
Temperature measurements possible even on the smallest scale / Molecular ruby for use in material sciences, biology, and medicine
Chemists at Johannes Gutenberg University Mainz (JGU) in cooperation with researchers of the German Federal Institute for Materials Research and Testing (BAM)...