On the Origin

Gradually there are more and more people becoming interested in endometriosis these days, which may be largely due to the internet allowing sufferers, researchers and clinicians to communicate effectively and efficiently (the fact that I would’ve been able to write this blog 20 years ago goes some way to prove this point), but endometriosis is not a modern disease, it is a condition that has been around for a very long time. If we take it to its logical conclusion, endometriosis is probably older than humanity itself. The fact that some species of primate, with which we share a common ancestor, can develop endometriosis in captivity suggests the disease is millions of years old (around 25 million years as an approximation).

Earliest accounts of endometriosis date back to Europe about 300 years ago, where it was described as ‘cysts’ in the pelvic cavity then later described in detail by a physician named Von Rokitansky in 1860. And yet throughout the long, sad natural history of endometriosis, it has only been during the last 100 years or so that we have actually gained any practical insight into the disease. Trying to find the origin of endometriosis in 20th century literature is especially difficult as the disease has not always been known as endometriosis.

A recent publication has found that a Canadian gynaecologist named Thomas Cullen was the first to identify the disease under the name ‘adenomyoma’ around 1908. However, it was not until Dr John Sampson started formulating his theories on the pathology of the disease (in particular retrograde menstruation) that it came to be known as ‘endometriosis’ which roughly translates as ‘disease inside the uterus’.

Thus it went from there; the number of papers published on endometriosis research has exploded over the years:
From 69 publications in 1960
To 125 in 1970
To 196 in 1980
To 430 in 1990
To 453 in 2000
To 901 in 2010
In total there are over 17,000 articles with endometriosis as a keyword published to date, a 13 fold increase over 50 years. So the scientific community have sat up, taken notice and are trying to come up with solutions that will hopefully be improving lives in the not too distant future.

A little bit more good news

Some of you may have read that endometriosis is associated with an increase in risk of certain cancers, in particular ovarian cancer. Whilst this is true, it was found that the risk only significantly applies to those with long standing endometriosis (i.e. between 10-15 years) and actual increase in risk is very small (only about 2-5%) after all, we can take some solace knowing that endometriosis is very common but ovarian cancer is not.

But while it may be saddening to hear you have an increased risk of certain cancers (even if the risk is small) perhaps the most important factor is the survive rate. The study I’ve referenced above found that women who have endometriosis and ovarian cancer tended to have their cancer diagnosed at a younger age, which may be beneficial as a good prognostic factor for cancer is early diagnosis.

The issue of survival of cancer in endometriosis patients is the focus of a recent study from Sweden. This study took 4,278 women with endometriosis and some form of malignancy and 41,831 women with malignancy but without endometriosis. The findings were quite encouraging as they found women with endometriosis had a better rate of survival for malignancies in general, but specifically better for breast and ovarian cancer. There was however, a poorer rate of survival for malignant melanoma (but remember, melanoma has excellent survival rates).

So although women with endometriosis have a slightly higher risk of developing ovarian cancer, it would seem women with endometriosis also have a better survival rate, funny how the universe balances out sometimes. Why might this be the case? I’m not completely sure, it may be that women with a chronic health condition like endometriosis are more aware of their health in general and may be more adept at detecting deviations from the norm that signal cancer, thus seeing their doctor sooner and getting treatment sooner. Of course women with endometriosis also see doctors more often, so the likelihood of incidentally discovering cancer earlier is also increased.