Endometriosis Classifications – rASRM, ENZIAN and #ENZIAN

Anyone who has ever had an endometriosis surgery report in their hand will have noticed these two classifications. What looks like a jumble of letters at first glance describes in just a few letters where and how much endometriosis was found.
The revised American Society of Reproductive Medicine (rASRM) score describes the location of the endometriosis, but is less likely to include deeply inflating endometriosis. The ENZIAN score is also used for this purpose.



The rASRM score was developed by the American Society for Reproductive Medicine and is currently the most widely used classification of endometriosis. The rASRM score is recommended by the guideline and DGGG for every operation with suspected endometriosis, i.e. the rASRM score belongs on every OP report and doctor’s letter after endometriosis operation.
It first assesses the areal spread of endometriosis on the ovaries and peritoneum. The peritoneum covers the entire internal organs in the abdominal and pelvic cavity. In addition, adhesions on the ovary, fallopian tubes and in the pelvis as a whole are assessed. Points are assigned according to the degree of involvement, which are then added together to give an overall score. This is used to determine the stage.
The stages are:


Stage Score Description
Stage I = rASRM I 1-5 Minimal Endometriosis
Stage II = rASRM II 6-15 Medium Endometriosis
StageIII = rASRM III 16-40 Moderate Endometriose
Stage IV = rASRM IV more than 40 Severe Endometriosis

The gentian classification describes the location and size of deep infiltrating endometriosis. The rASRM classification does not consider deep infiltrating endometriosis. Large deep infiltrating foci that grow in depth but not in width, for example in the pelvic walls or on the bowel do not lead to an appropriate increase of the rASRM score, as this measures the size at the peritoneum. Therefore, this aspect is additionally covered by the ENZIAN score.
Depending on the localization, a letter combination is assigned. For the letters A-C there is an additional number describing the size. The exact classification is shown in the tables and the figure.





Stage
A B C
Localization Septum rectovaginale = Between rectum and vagina/cervix Deeply infiltrating into the lateral pelvic walls, lateral uterine ligaments, or around the ureter deeply infiltrating the rectum / rectal cavity
1
less than 0,39 inch A1 B1 C1
2
0,39 -1,18 inch
A2 B2 C2
3
more than 1,18 inch A3 B3 C3



Designation Description
FA Adenomyosis – endometriosis in the uterus
FB Endometriosis on the bladder
FU Ureter intrinsic = growing into the ureter
FI Other parts of the intestine except the rectum (rectum is classified as C). For example, small intestine, remaining colon or appendix.
FO all other localizations (Other): Lung, Diaphragm, Brain, etc.



While the original ENZIAN classification was only concerned with deep infiltrating endometriosis, the #ENZIAN classification can now describe all areas and manifestations of endometriosis. Thus, the whole endometriosis can be described in one classification.
The classification thus builds on the ENZIAN classification described above. All letters and number combinations described there remain the same.
Added are the areas:
P – the peritoneum (the peritoneum): This can be classified as level P1 (under 3 cm), P2 (3-7 cm) or P3 (over 7 cm) depending on the surface area that is affected. What is meant by centimeter is the diameter of a circle that can be placed over the endometriosis focus. An area as large as a 1 euro piece would be considered P1, a focal area approximately as large as a 5 cm diameter circle would be P2.
O – the ovary (the ovary): Here, each side is individually designated as right or left. Here, too, there is a division into O1, O2 and O3 depending on the size of the findings. These are based on the diameter of the sum of the endometriosis cysts on the respective side. Om describes a missing ovary.
T – the tube/ tuboovarian complex (tube = fallopian tube, tubovarian =at the fallopian tube and ovary): The letter T is used to describe stuck or connected findings from the fallopian tube/ovary. Endometriosis lesions can cause adhesions of the fallopian tubes and ovary to surrounding tissue, affecting mobility and function. T1 describes adhesions that extend to the pelvic wall. In T2, the complex also “adheres” to the uterus, and in T3, additional structures such as the intestine or the wider connective tissue structures such as the uterosacral ligament. Each side is assessed and described individually as right or left.
Fallopian tube patency testing can also be described under area T. A positive tubal patency test is described as T+, and a negative one for non-patency ovaries is described as T-.
And one more innovation – the classification can be used both in surgery and before surgery via ultrasound or MRI. This is expressed by small bracketed letters.
(u) – Ultraschall
(s) – pro Operation (chirurgisch/surgery)
(m) – MRT
Not all areas can be adequately visualized by ultrasound or MRI, but findings that are found can now be described accordingly in the #Dencian classification.
If something cannot be assessed, it is marked with an (x).
Eine Übersicht gibt es hier;



These two classifications can be used to describe surgical results and anatomical spread of endometriosis very accurately. They are usually used on every surgical report so that other practitioners can quickly understand the surgical situation. The specification of these classifications is therefore also required for certification as an endometriosis center.
The score is a snapshot; the situation may be different at the next operation. In addition, there are sometimes differences in assessment between surgeons. [1]
High Stage = Severe Pain?
The classifications do not include symptoms. Even though statistically a higher rASRM / ENZIAN stage is associated with more severe pain on average [4], one cannot draw direct conclusions from rASRM stage to symptoms. Some women with endometriosis rASRM stage IV have no pain and even endometriosis rASRM stage I can cause hellish discomfort.
Stage and Fertility
Fertility is also not conclusively considered in these scores. For this purpose, fertility centers additionally determine the endometriosis fertility index, which includes the rASRM and other scores, as well as general factors such as age and previous fertility problems. [2,3]
Stage and Prognosis
Experts also agree that these classifications say little about the prognosis of the disease or response to therapy. [2] Rather, it is relevant whether a complete removal has taken place, what complaints existed previously, etc.



rASRM and ENZIAN are therefore important and accurate scores for describing endometriosis, but can only provide indirect information on symptoms, therapy prognosis and fertility. They should always be used together to provide a conclusive picture of superficial and (if present) deep infiltrating endometriosis.