Page 11 - Diagnostic delay of endometriosis

Endometriosis is defined as the presence of endometrial-like tissue (glands and stroma) outside the uterus, which induces a chronic inflammatory reaction.1 The condition is estrogen-dependent and predominantly found in women in their reproductive life span. It is one of the most common benign gynaecologic conditions. The exact prevalence of endometriosis is unknown but estimates range from 2 to 10% within the general female population up to 50% in women presenting with subfertility or chronic pelvic pain.2-5 The clinical presentation can be highly variable. Endometriosis may be suspected based on a woman’s history, symptoms and signs; the diagnosis is affirmed by findings in physical examination and imaging techniques, and finally proven by histology of either a biopsy from a directly visible lesion or tissue collected during laparoscopy.4 The disease negatively affects several aspects of women’s lives, including their physical and emotional wellbeing, social roles and ability to work.6-8 Besides the impact on individual quality of life, the cost of endometriosis is a burden to society due to medical costs of treatment and economic costs because of the inability to work, which is comparable to other chronic conditions like diabetes mellitus.8
Etiology
Although endometriosis is one of the most commonly encountered problems in gynaecology, its pathogenesis is still poorly understood and remains controversial. The discovery of the condition is a topic of debate as well.9-11 Microscopic findings in line with the present understanding of endometriosis were first described by the Czech pathologist Karl von Rokitansky in 1860, reporting about endometrial glands and stroma present in ovarian and uterine neoplasias.12 The full morphological and clinical picture of endometriosis (and adenomyosis) was first described by the surgeon Thomas Cullen in 1908.13 However, it was John Sampson who created the name “endometriosis”. His original observation came when he operated women at the time they were menstruating, and observed that the peritoneal lesions were bleeding.14 In 1927, Sampson postulated that the presence of endometrial cells outside the uterus was due to tubal dissemination of menstrual shedding.14
There are three main concepts with regard to the pathogenesis of endometriosis: 1) the in situ development theory, the concept that endometriosis develops from local tissues, such as the germinal epithelium of the ovary, remnants of the Wolffian or Müllerian ducts or from metaplasia of mesothelial cells lining the pelvic peritoneum, 2) the induction theory, the
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