Endometriosis, a complex and often painful condition, is characterized by the growth of endometrial-like tissue outside the uterus. This tissue, which differs molecularly and in behavior from the lining of the uterus, can cause severe discomfort and various health complications. One such complication is the formation of endometriomas, sometimes referred to as “chocolate cysts”, which predominantly affect the ovaries. They’re named for their dark, chocolate-like appearance, resulting from the accumulation of old blood within the cyst.
But does the presence of endometriomas automatically classify a patient as having stage 4 (also designated Stage IV) endometriosis? This primer delves into the stages of endometriosis, the nature of endometriomas, and the relationship between the two.
Table of contents
Understanding Endometriosis and Its Stages
Endometriosis is categorized into four stages according to the American Society of Reproductive Medicine (ASRM), with each stage reflecting the location, extent, and superficial vs deep endometriosis implants, presence and severity of adhesions, and the presence and size of ovarian endometriomas. The current revised ASRM system (rASRM) was adopted in 1996 and remains the most common staging system. Unfortunately, there is a lot of inter-observer variation, so reproducibility of the score is poor. It also is limited because it mixes visual staging and actual biopsy proven staging. So, one surgeon might call it one stage and another surgeon may arrive at a different stage. In addition, rASRM stages do not correlate well with degree of pain and does not fully consider presence and location of deeply infiltrating endometriosis (DIE).
For all of the above reasons, other staging systems have been introduced. The ENZIAN system, which more robustly considers the location and depth of DIE, was intended to supplement the rASRM system but due to numerous misunderstandings it is not widely used. The endometriosis fertility index (EFI) focused mainly on predicting pregnancy rates. The American Association of Gynecological Laparoscopists (AAGL) proposed a comprehensive system to try to address pain, infertility/subfertility, and surgical excision difficulty. However, it was only recently published in 2021, continues to have limitations of not addressing upper abdominal and extra-abdominal disease, and is not yet widely accepted.
So, we are left with the rASRM system in terms of best communicating surgical outcomes, treatment planning and comparing results. The Stages are based on a numerical score and are as follows:
Stage I: Minimal Endometriosis
In stage I, there are only a few small clumps of endometriosis tissue, also known as implants. These may be found in the tissue lining the abdomen or pelvis.
Stage II: Mild Endometriosis
In stage II, there are more implants than in stage I, which may be either superficial or deep, with mild adhesions. Stage II is typically characterized by more extensive endometriosis with deep implants present.
Stage III: Moderate Endometriosis
In stage III, deep implants of endometriosis tissue are present. Adhesions may be dense rather than filmy and thin. As a result, endometriosis at this stage is more widespread than in stage II.
Stage IV: Severe Endometriosis
Stage IV, or severe endometriosis, is typically associated with numerous deep endometriosis plaques, large endometriotic cysts on one or both ovaries and many dense adhesions. There is usually also extensive scar tissue in the abdomen and signs of intense inflammation and scarring or fibrosis.
Read More: Can Endometriosis Cause Bowel Issues?
The Nature of Endometriomas
Endometriomas are endometriosis cysts that primarily affect the ovaries. Endometriomas can occur on one ovary or both and affect between 20-40% of patients with endometriosis, many of whom also have stage III-IV disease. The origin of endometriomas is incompletely known, just like endometriosis in general, but likely multifactorial in principle.
Endometriomas and Stage 4 Endometriosis: The Connection
The question is, “Do endometriomas automatically make you stage 4?” The answer is not straightforward. The presence of ovarian endometriosis or an endometrioma of course contributes to the staging of endometriosis. Each ovary can contribute between 1 and 20 points, varying based on tiny implants to endometriomas greater than three centimeters in size. However, the presence of endometriomas alone does not automatically classify a patient as having stage 4 endometriosis, which requires 40 or more points. In addition to ovarian endometrioma, presence or absence of surrounding adhesions also contributes to the point total. Also, larger endometriomas are often associated with extensive deep pelvic disease. So, in general, small endometriomas may not mean Stage 4. But larger ones are quite likely to mean Stage 4 disease is present.
Read More: What Does Bowel Endometriosis Feel Like? Understanding the Pain and Symptoms
Treatment Options for Stage 4 Endometriosis and Endometriomas
The treatment of stage 4 endometriosis and endometriomas is complex and highly individualized. It depends on various factors, including the patient’s symptoms, age, desire for pregnancy, and overall health.
Treatment options for stage 4 endometriosis can include a combination of hormonal therapy, pain management, and surgery. While hormonal therapy may help control pain it is highly unlikely to shrink endometriomas, let alone resolve them, or effectively treat endometriosis. This is due to the relative resistance of endometriosis to progesterone and progestins and incomplete dependence on estrogen. There are major potential health risks and this should be part of the discussion with your chosen endometriosis specialist. Pain management strategies include over-the-counter and prescription medications, as well as physical modalities like pelvic floor therapy and transcutaneous electrical nerve stimulation (TENS) units. While this can help manage chronic pain associated with the condition this does not treat the root cause, which is endometriosis and resulting fibrosis.
Minimally invasive surgery under the care of an extremely well trained surgeon is the cornerstone of advanced endometriosis treatment. This is not surgery that should be undertaken by novices or most general gynecologists. The reason is mainly due to the fact that anatomy can be severely distorted, making surgery very challenging in terms of achieving excision while limiting complications which can be life threatening or at least very morbid.
Specifically regarding endometriomas, endometriomas require excision, not drainage. Draining is very ineffective and the endometrioma can soon recur. Ideally, any surgical spillage should be minimized because it is not just old blood but also potentially endo-related stromal stem cells, which can implant and grow elsewhere. Overall, the planning and timing of surgery varies significantly. Often decisions have to be made based on whether or not fertility is the main concern or pain, or both in equal degrees. Surgical planning is complex and requires a master surgeon for optimal outcomes. Especially for the management of Stage 4 endometriosis and endometriomas a highly trained and skilled endometriosis specialist and surgeon is mandatory for your success.
Read More: Life After Endometriosis Surgery: A Comprehensive Guide
References:
Risk factors for coexisting deep endometriosis for patients with recurrent ovarian endometrioma
