Genetic testing can identify men who have more than a 10-fold increased risk of testicular cancer, a UK study has found. The discovery could lead to the development of clinical tests to identify men at highest risk so they could be offered preventative treatment or monitoring.
Researchers at the Institute of Cancer Research, London, found that testing for newly-identified genetic factors, along with others found in previous studies, enabled identification of men at increased risk.
Testicular cancer is the most common cancer in young men in the UK and Ireland – the Republic has on average 172 new cases every year, according to the National Cancer Registry.
Treatment with platinum chemotherapy is usually successful but some do not respond, and as men are typically diagnosed in their 20s or 30s, they may have to live with longterm side-effects of chemotherapy.
The ICR team studied the DNA of 30,000 men and identified 19 new genetic changes associated with the disease. Testing these alongside previously identified genetic factors – covering 44 genetic markers – picked out 1 per cent of men at highest risk of the disease.
Genetic errors
It compared DNA from 7,319 men with testicular cancer with that of 23,082 without the disease from three separate studies. By reading the DNA code of these men in detail, researchers were able to pick out “single letter” changes in their DNA that increased their risk of developing testicular cancer. The team looked at what happened inside cells that caused the newly-discovered genetic errors to lead to cancer.
The study, published in the latest issue of Nature Genetics, also uncovered clues about how risk genes are activated. It was funded by the Movember Foundation, a charity that supports men's health initiatives internationally, including Ireland.
Study leader Dr Clare Turnbull said: “Our study has almost doubled the number of DNA variations linked to increased risk of developing testicular cancer and advanced our ability to use genetics to predict disease in healthy men.”
ICR chief executive Prof Paul Workman said: “Large-scale genetics studies, such as this one, are a crucial part of our mission to defeat cancer. The more we understand about the genetics of cancer, the better we can pick out people at most risk before they develop the disease.”
