Endometrioma Recurrence

Breaking the Cycle: Understanding Endometrioma Recurrence After Surgery

Endometriomas, commonly known as ovarian “chocolate cysts,” occur in 20 to 40% of endometriosis patients. Abnormal implantation and growth of endometrial-like tissue can cause these cysts to form on the ovaries, which can cause more pain, discomfort, and fertility issues. With each cycle, the cyst bleeds into itself, just like what occurs typically inside the uterus.  Except that uterine endometrial tissue is expelled during menses vaginally, whereas endometriotic blood is trapped inside the ovarian cyst and with each cycle, the cyst slowly gets larger.  So, this blood also becomes old and turns brown over the years, resembling chocolate.  While surgery can be an effective treatment for endometriomas, the recurrence of these cysts after surgery is a common problem. We will explore why this occurs and what can be done to reduce the risk of recurrence. 

Several factors contribute to the recurrence of endometriomas after surgery. One of the main factors is the nature of the condition itself. The presence of endometriomas may signal more aggressive endo disease, and this chronic and progressive inflammatory disease on the ovary can continue to grow. Endometriosis tissue might be left behind after surgery because it can be buried deep in the ovary and even be microscopic.  So, the nature of the disease is to grow back in various parts of the ovary, superficial and deep. 

Surgically removing an ovary will certainly prevent endo from growing back in that area and that was the standard approach for many decades. However, in recent years, there has been a shift towards more conservative surgical techniques for treating endometriomas. These techniques aim to remove as much of the endometriosis tissue as possible while preserving as much of the ovary as possible. This is called a cystectomy and is often used for the removal of other ovarian cysts such as dermoids (teratomas) or cystadenomas (benign ovarian tumors).  The problem is that, unlike these other cysts, endometriomas are more inflammatory and the edges are irregular, so they do not easily separate from ovarian tissue.  So, microscopically incomplete removal is common even if it appears that the entire cyst was removed.  

Another surgical factor contributing to recurrence is rupture of the endometriotic cyst during the surgical removal. Rupture can release not only old blood but also endometriosis cells and tissue into the pelvis.  It’s crucial to repeat that it is not just old blood that is spilled.  This can lead to a higher risk of recurrence of endo on the ovary and elsewhere because these spilled cells can create new implants.

Here is an important side note. Although rare, endo can degenerate into a type of cancer or increase the risk of ovarian cancer.  The older you are and the more there is a concerning family history, the more an atypical looking endometrioma may be more than that.  If an early cancer is ruptured, the treatment can be more difficult.  How rare? It is on the order of 1% or less increased risk.  But given that there are millions of women with endo, even a fraction of 1% means thousands at risk.  If you are at higher risk due to age, genetics, or family history, especially if the imaging shows the endometrioma is not typical, getting a consult with a gynecologic oncologist may be prudent. 

A study published in the Journal of Minimally Invasive Gynecology found that the recurrence rate for endometriomas was significantly higher in cases where the cyst had ruptured during surgery than cases where the cyst was removed intact. The study found that the recurrence rate for ruptured cysts was 50%, compared to a recurrence rate of 8% for intact cyst removal.   

Having said all the above, while it seems like removing the endometrioma intact is a no-brainer strategy, this is far easier said than done.  As we mentioned before, these cysts do not readily separate from the ovary, can be stuck to surrounding structures like the uterus or bowel, and can be very thin walled.  So, even in a skilled surgeon’s hands, this often leads to inadvertent rupture.  But read on.  There are still things an expert surgeon can do to minimize this risk of rupture and spill inside the pelvis. So, spoiler alert #1 is to make sure you are under the care of an expert endometriosis surgeon.  But there is more to it, much more. 

Non-Surgical Recurrence Factors

Endometriomas are largely estrogen-dependent, meaning that they grow and spread in response to the hormone estrogen.  So, suppose at least one of the ovaries is left behind. In that case, the estrogen can stimulate growth of any endometriosis tissue left behind on the ovary or anywhere else that any endo implants may be hiding.  

To address this main hormonal non-surgical risk factor, there are several proactive steps that women can take to reduce endo recurrence. One of the most important steps is maintaining a healthy lifestyle, reducing total estrogen. This includes eating a healthy diet, getting regular exercise, reducing stress, using probiotics to metabolize excess estrogen, and avoiding exposure to toxins that can act as xenoestrogens. These steps can help to balance estrogen and progesterone in the body and reduce the risk of endometriosis growth and recurrence.

In many cases, pharmaceutical hormone therapy may be recommended to reduce the risk of recurrence. However, hormone therapy is not suitable for everyone and may have serious side effects.  Work with an endo specialist on this. 

There is much more to the non-surgical risk for recurrence and other proactive steps can be taken.  I

Surgical Innuendoes

Laparoscopy has been a standard for endometriosis surgery for over 40 years.  It was invented almost a hundred years ago, but video cameras achieved acceptable quality only during the latter part of the 20th century.  While this is still the standard bearer for most endo surgery, the more complex the surgery the more one can strongly argue that a 2-dimensional camera (no depth perception) and instruments that are like inflexible chopsticks with graspers and scissors at the end are just too clunky and plain inadequate for finesse meticulous surgery.    

Robotic surgery is a newer surgical tool and technique that has become increasingly popular over the past decade, with very good reasons.  It is minimally invasive, just like laparoscopy and the incisions are just as hidden in expert surgeons’ hands.  However, this technique involves the use of several robotic arms that are controlled by a surgeon to perform minimally invasive surgery.  This is where the magic happens. The robotic arms are equipped with exchangeable tiny instruments that wrist or flex like human hands and a magnified 3-D camera, which allows incredibly precise visualization and depth perception.  Also, even the slightest tremor in a surgeon’s hand is not transmitted to the instrument like it is in regular laparoscopy.  In fact, with traditional laparoscopy, any tremor or inadvertent motion of the surgeon’s hand is amplified at the instrument tip.   So robotic surgery translates into less trauma to the body, more accurate dissection, and less blood loss, all of which may mean faster recovery.   For simple cases, there may not be much of a difference.  But, unfortunately, it is not possible to predict what might be found in the pelvis until the surgery actually starts.  So, having the robotic equipment available and an expert surgeon in its use is quite helpful to cover all options.      

One of the key advantages of robotic surgery for treating endometriomas is that, in expert hands, it may allow for more complete removal of lesions, especially endometriomas. This is simply because the robotic camera and equipment are more precise and technologically far superior to laparoscopic equipment. Of course, at the end of the day, in most cases, the level of expertise of the surgeon trumps equipment.  But in any given complex and anatomically distorted surgical situation an uber expert in robotics will likely fare better than an uber expert in laparoscopy.   

In advanced endo, endometriomas are often stuck to each other in the middle (“kissing ovaries”), pulling the rectum up into an inflammatory mess.  Deeper they are also stuck to the uterosacral ligaments supporting the uterus, which also pulls the ureters dangerously close to harm’s way (a few millimeters at most).  Removing these endometriomas intact and avoiding damage to the rectum or ureters requires both an uber good surgeon and the very best technology, which is embodied in robotics.  Suppose the surgeon is good at retroperitoneal surgery (deep tissues behind the peritoneum where the ureters are). In that case, it is possible to mobilize the whole ovary or ovaries up out of the pelvis without rupture.  Then, even if it appears that removing endometriomas might result in rupture (extreme inflammation), a special containment bag can be placed underneath to catch the fluid and endometriosis cells in the event of a rupture.  Finally, if all else fails, a very controlled evacuation of an endometrioma using specialized suction equipment is better than overt rupture.  Unfortunately, most surgeons, even some advanced surgeons, are incapable of or do not routinely employ these steps.  The result is higher risk of recurrence if there is uncontrolled spill. 

In conclusion, the rupture of endometriomas during surgical removal can significantly increase the risk of recurrence. Careful and precise surgical techniques, such as those used in robotic surgery, may help to reduce the risk of cyst rupture and subsequent recurrence. However, other factors, such as hormonal imbalances, the presence of endometrial implants, and lifestyle and environmental factors, should also be considered when developing a treatment plan. 

Get in touch with Dr. Steve Vasilev

More articles from Dr. Steve Vasilev:

Endometriosis And Menopause; Everything You Need To Know

How to tell the difference between endometriosis and ovarian cancer

What would happen to the signs and symptoms of endometriosis after menopause?


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