Womb cancer deaths have risen by a fifth over the past decade, according to Cancer Research UK. The rise has received high-profile news coverage, with newspapers and television news highlighting that the number of deaths is rising as more women are being diagnosed with the disease.
The news is based on new data on trends in womb cancer diagnosis, survival and death. These data reveal that the number of diagnoses remained static for many years, but has increased by 43% since the 1990s. As the number of womb cancer cases have increased over the last decade, so have the number of womb cancer deaths. However, survival has also improved during that period, with 77% of women who are diagnosed with womb cancer now surviving for five years or more.
Although it is often not given the same attention as other female cancers, such as breast cancer, womb cancer is the fourth most common cancer in women, and the ninth most common cause of cancer death in women in the UK. The cancer is most common in post-menopausal women, with cases peaking in women between the ages of 60 and 79 years.
News stories have generally said that the increase in cases of womb cancer (also known as uterine cancer) is due to an increase in obesity. However, it should be that while obesity is thought to be a contributing factor, the exact causes of the rise are not yet clear.
How have womb cancer rates changed?
According to Cancer Research UK’s figures, the number of womb cancers diagnosed each year had remained fairly stable for approximately 20 years, but since the mid-1990s the number of cases appears to have increased sharply.
To put this into context, in 1997-1998 there were 13.7 womb cancer cases per 100,000 women, but by 2010 the number of cases had increased to 19.6 per 100,000 women. This equates to a 43% rise in diagnoses in little more than a decade. While such an increase is obviously worrying, it should be noted that a 43% increase is a relative figure, and that, in absolute terms, this amounts to an additional 60 cases diagnosed per 1 million women each year. In the same period cases of many other cancers have fallen.
How have death rates changed?
Cancer Research UK has also highlighted that the number of deaths due to womb cancer has similarly increased over the past decade. From the early 1970s to the late 1990s, annual deaths due to womb cancer had steadily fallen, from 4.7 womb cancer deaths per 100,000 women to 3.2 per 100,000. Since the early 2000s, however, the number of deaths each year began to climb, from 1,481 womb cancer deaths in 2000 (3.1 per 100,000) to 1,937 deaths in 2010 (3.7 per 100,000). This equates to a 17.9% increase in the number of deaths per year over the course of the decade. Again, it is important to remember that this is a relative figure. In absolute terms, this equates to an additional 6 deaths per 1 million women each year.
What has caused the rise?
Several media outlets have reported that obesity has caused the increase in uterine cancer deaths. This is an inappropriate interpretation of both the data and the Cancer Research UK press release. While Cancer Research UK reports that obesity has been shown to double the risk of developing womb cancer, it is not possible, based on the current data, to establish that obesity has caused the specific increase in womb cancer diagnoses and deaths seen in the UK. An increase in obesity could feasibly account for the increase, but this remains a theory without suitable evidence to support the claim.
Cancer Research UK does report that experts believe obesity could be a key factor in the increasing number of diagnoses, but also points out that “we don’t yet fully understand what’s driving up cases of womb cancer”. In addition to obesity, there are several other risk factors for womb cancer, including not having children.
In short, the causes of the rise are not clearly known, and theories suggesting reasons currently appear to be unproven.
How have survival rates changed?
In the context of the increasing number of uterine cancer diagnoses and deaths, it is important to note that survival rates are actually increasing.
While that seems a contradiction, the data show that more women are successfully being treated for the condition, and that they are generally living longer after diagnosis. (Cancer survival is often quoted in how many years people live after their diagnosis, rather than whether they ‘survive or not’.) In the early 1970s, 61% of women diagnosed with womb cancer lived for five years or more. Of women diagnosed in 2000 to 2001, 77% lived for five years or more. This is a 16% increase in survival over 30 years.
What are the signs of womb cancer?
The signs and symptoms of womb cancer include abnormal vaginal bleeding (including bleeding in post-menopausal women, unusually heavy bleeding, bleeding between periods and unusual vaginal discharge), lower abdomen pain and pain during sex. Cancer Research UK says that while these symptoms do not usually mean cancer, it is very important to have them checked by a doctor. The symptoms may be due to another more common condition, but if they are due to womb cancer, early diagnosis can improve the chances of successful treatment.
The vast majority of womb cancers are detected in women over the age of 50, although it can still occur in younger women.
How can I cut my cancer risk?
No one knows exactly what causes womb cancer, but there are several factors that increase a woman’s risk of developing the disease. Overweight and obese women are significantly more likely to develop womb cancer than women who are at a healthy weight. Additionally, not having children and having a family history of the disease have been shown to significantly increase the risk of developing the disease. Cancer Research UK suggests that one of the best ways to reduce the risk of developing womb cancer is to maintain a healthy body weight.
As mentioned above, increasing age is an unavoidable risk factor for womb cancer, and most women diagnosed are over the age of 50. While there is nothing that can stop us aging, it is important that older women know the signs and keep an eye out for them.
Womb cancer deaths 'are rising'. BBC News, April 5 2012
Deaths from womb cancer rise by a fifth: Cancer Research UK. The Daily Telegraph, April 5 2012
Womb cancer deaths increase by 20 per cent. The Independent, April 5 2012
Womb cancer deaths increase of 20 per cent blamed partly on obesity rise. Metro, April 5 2012
Cancer Research UK: Womb cancer deaths rise by a fifth in the last decade. Published online April 5 2012