El limbo jurídico o la incertidumbre sobre el régimen aplicable a la capital

An ideal classification system has a good scientific basis, is unambiguous in its terms, is applicable for all cases, has a true reflection of the disease and is comprehensive and reproducible. It should aim to accurately translate physical findings into verbal descriptions which are easy to discuss with patients.

Ideally it should standardise the disease irrespective of who is performing the assessment, be a reflection of disease severity, and be a good measure of the effect of treatment on disease⁵⁴. Classification systems may be of value in the prognosis and management of infertility^59,60 but there are limitations to the use of these classification systems. Endometriotic lesions also have a wide spectrum of appearances varying from black/blue/brown puckered lesions termed, peritoneal or ovarian ‘powder burn’ or ‘gunshot’ lesions, to overt haemorrhagic cysts and nodules. Milder or more subtle lesions, which may be harder to spot, may look like red implants or serous clear vesicles. White plaques, as well as peritoneal disco loration may manifest when fibrosis is involved³¹. Lesions can cause extensive scarring involving the large and small bowel, the fallopian tubes and in rarer cases, other extraperitoneal locations such as the lung and brain.

The depth of lesion infiltration is known to correlate with the type and symptom severity of patients^61-63. Deep lesions will extend over 5mm beneath peritoneal surfaces. It is these deep infiltrative lesions that invade abdominal structures such as the bladder, ureters, the intestine, uterus, uterosacral ligaments and occasionally the vagina and cervix.

1.5.1 American Fertility Society classification

The American Fertility Society was the first society to propose a quantitative classification system in 1979⁶⁴. It consisted of a paper document with defined classification points and the ability to be flexible for its use in varied cases of the disease. Its aim was to define the severity of disease by its location and extent. It did not however enable a correlation between disease severity and pregnancy rates so in 1982 Guzick et al.⁶⁵ proposed an amendment to the original classification by adding on a nonparametric monotonic estimator where a dose response relationship between AFS score (dose) and pregnancy post treatment (response) were used to improve the discriminatory power of the classification⁶⁵. In 1982 attempts at the use of clustering techniques for the anatomical findings to predict pregnancy rates failed⁶⁶. Other reviews within the same period provided additional recommendations to the classification system but recognised the failure and difficulties encountered in creating an “ideal” classification system partly due to the wide spectrum of disease^67,68. The AFS classification⁶⁷ was revised in 1985 with additional details. These included quantification of ovarian adhesions, differentiation between superficial and deep lesions on the ovaries and peritoneum, recognition of minimal disease, creation of a tubal endometriosis category and the recording of the presence of other pathology⁵⁴. In 1992, Canis et al. proposed an additional stage for endometriosis which he suggested could be added on to the AFS⁶⁹. This Stage V classification was meant to be attributed to cases with severe bilateral disease that would require early in vitro fertilisation (IVF) intervention to achieve fertility. Irrespective, fertility itself is found to be reduced in severe disease⁷⁰. In 1996, there was a re-publication of the classification system with illustrations for pelvic pain⁵⁸ and the AFS was renamed as The American Society for Reproductive Medicine (ASRM) classification system (Figure 1-1).

1.5.1.1 Limitations of the American Society for Reproductive Medicine (ASRM) classification

It is maintained that although the ASRM classification is useful in documentation of disease, it fails clinically to predict prognosis or management options for pain or infertility⁵⁴. Identified limitations include wide scoring ranges, possible observer errors in recognising disease due to its variation in morphology⁷¹, fluctuations in disease presentation according to hormonal stage of the cycle⁷² and variations in reporting of disease depending on operative technique e.g. laparoscopy versus laparotomy⁷³. Articles assessing the reproducibility of the ASRM system identify substantial intra observer staging, especially when assessing endometriosis within the pouch of Douglas or ovaries⁷⁴. Disagreement in reporting multiple lesion types in the same patient make the classification and staging of disease difficult⁷⁵. The ASRM (except in extensive disease) also correlates poorly with infertility⁷⁶ and there is also poor correlation with pelvic pain⁷⁷, dyspareunia, dysmenorrhoea and extent of disease⁷⁸. The ASRM is therefore unable to encompass the role of a disease predictor or monitor of outcome of treatment.

Other classifications by Chapron et al. in 1993⁵⁹ looked at deeply infiltrating disease and its surgical implications. Alternate classification categories have tried to modify that of the ASRM by focusing on varied aspects such as pregnancy rates⁷⁹, pain levels⁸⁰, radiological, histological and morphological factors or biomarkers and genetic markers. Classification systems for disease affecting a particular location such as retrocervical endometriosis, were attempted in 1993 by Adamyan et al. and updated in 2001⁸¹. The multitude of attempts at classification reflects the broad spectrum of clinical presentations and symptoms.

The ESHRE have developed a guideline for the diagnosis and classification of endometriosis. Disease severity is assessed by describing surgical findings or using the standardised ASRM classification.

FIGURE 1-1

The American Society for Reproductive Medicine (ASRM) classification of endometriosis (1996)⁵⁸