This is not a small scale study, but took place over a 15 year period from 1994 to 2009 and involved more than 1,500 prostate cancer patients at The Royal Marsden NHS Foundation Trust in London and Surrey, Nottingham City Hospital and The Royal Hallamshire Hospitals in Sheffield, along with more than 3,000 healthy control cases.
The study was led by The University of Warwick and The Institute of Cancer Research (ICR) and their findings may seem like the stuff of fairground palm reading, but apparently men whose index finger is longer than their ring finger were one third less likely to develop the disease than men with the opposite finger length pattern.
The most common finger length pattern, seen in more than half the men in the study, was a shorter index than ring finger. Men whose index and ring fingers were the same length (about 19 per cent) had a similar prostate cancer risk, but men whose index fingers were longer than their ring finger were 33 per cent less likely to have prostate cancer. Risk reduction was even greater in men aged under 60 years- these men were 87 per cent less likely to be in the prostate cancer group.
Given the size of the study this is encouraging to think that this could be a very simple test to determine “prostate cancer risk from simply looking at relative finger length. Joint senior author Professor Ros Eeles from the ICR and The Royal Marsden NHS Foundation Trust believes that it could be particularly helpful in men aged under 60 who are often more reluctant to visit a doctor for any particular complaint as it could be used to select at-risk men for ongoing screening, perhaps in combination with other factors such as family history or genetic testing.
It is the hormone levels that babies are exposed to in the womb which can have an effect many decades later. The relative length of index and ring fingers is set before birth, and is thought to relate to the levels of sex hormones the baby is exposed to in the womb. Less testosterone equates to a longer index finger; the researchers now believe that being exposed to less testosterone before birth helps protect against prostate cancer later in life. The phenomenon is thought to occur because the genes HOXA and HOXD control both finger length and development of sex organs.
Previous studies have found a link between exposure to hormones while in the womb and the development of other diseases, including breast cancer (linked to higher prenatal estrogen exposure) and osteoarthritis (linked to having an index finger shorter than ring finger).