Incidence of anal cancer have soared by almost 300% in the UK since the 1970s, new figures have shown.
The charity Cancer Research UK said incidences of the “taboo” cancer had risen more dramatically in women than in men. Their experts believe the change is linked to increasing infections of human papillomavirus (HPV), which is transmitted through sexual activity.
The virus is well known as a trigger of cervical cancer, but also linked to 90% of anal cancers.
Previous research has suggested a connection with anal intercourse, but the charity stressed that any sexual activity increases the risk of passing on HPV.
Smoking may also be a risk factor. While smoking rates have dropped since the 1970s, the reduction has been less pronounced in women.
Nick Ormiston-Smith, Cancer Research UK’s head of statistics, said: “These are very worrying findings and highlight an increase in a cancer that’s not often talked about.
“Around 1,200 people are diagnosed with cancer of the anus every year in the UK, which means it’s still a relatively rare disease. But the rise in incidence, particularly in women, is concerning.
“We don’t fully understand the reason for the difference between men and women, but we do know HPV and smoking are strong risk factors for the disease.”
Overall, anal cancer incidence had risen from 0.4 cases per 100,000 of the population in the mid 1970s to 1.5 per 100,000 today.
Around six people now die from the disease each week in the UK, representing a quadrupling of death rate in the past 40 years.
Jessica Kirby, senior health information manager at Cancer Research UK, said: “Anal cancer is closely linked to HPV, and changes in sexual attitudes mean people are increasingly exposed to the virus.
“We’re not suggesting people take a vow of celibacy, but HPV vaccination, using a condom and being a non-smoker can all help to reduce the risk.
“Early diagnosis is also important so report any unusual or persistent changes in your body or bowel habits to your doctor.
“The most common symptom is bleeding from the anus. The cause is much more likely to be something less serious but it’s important to report symptoms to your doctor and get them checked out.”