**2. Pathologic features of endometriosis**

The most common site of involvement is the ovary, but virtually all pelvic organs can be affected by the disease.

Ovarian endometriosis includes a superficial form, which appears as small punctuate foci measuring no more than 5 mm, and a 'deep' one; in the latter case the typical aspect is that of the "chocolate cyst" or "endometrioma". Chocolate cysts typically have thick, fibrotic walls, a dark-brown, viscous content and their diameter rarely exceed 15 cm.

Aspect of endometriotic peritoneal implants ranges from punctuate foci to small stellar patches; according to the age of the lesion and the amount of pigment, they could appear white, yellow, red, blue or brown (**Fig. 1**).

Fig. 1. Endometriotic nodules as they are seen in laparoscopy

American Fertility Society [4]. The rAFS score takes into account the presence of ovarian and peritoneal implants (subdivided into superficial or deep), the severity of the adhesions and the presence or not of a complete posterior cul-de-sac obliteration (i.e. frozen pelvis). The rAFS staging system has shown poor correlation to the clinical severity of the disease, so requiring further refinement. Meanwhile a new staging system called ENZIAN score has been recently developed [5]; it is focused on the deep pelvic endometriosis that is the most

The clinical value of this staging system and its correlation to the reproductive prognosis of

Therapeutic options are observation, medical treatment, surgery or a combination strategy. The most widely used medical therapy of endometriosis includes oral contraceptives, androgenic agents, progestins, and gonadotropin releasing hormone (GnRH) analogs. The choice of a surgical option depends upon the severity of the disease. Surgery is the main therapeutic option in patients with deep pelvic endometriosis. Anterior cul-de-sac endometriosis involving the bladder can be treated with laparoscopic surgery. Preoperative staging of disease is necessary because in certain cases surgery should be performed by standard laparotomy (bladder endometriosis associated with bowel involvement). Treatment of posterior cul-de-sac endometriosis can be achieved with laparoscopy, but a vaginal or a laparotomic approach is needed when vaginal or severe bowel disease,

The most common site of involvement is the ovary, but virtually all pelvic organs can be

Ovarian endometriosis includes a superficial form, which appears as small punctuate foci measuring no more than 5 mm, and a 'deep' one; in the latter case the typical aspect is that of the "chocolate cyst" or "endometrioma". Chocolate cysts typically have thick, fibrotic

Aspect of endometriotic peritoneal implants ranges from punctuate foci to small stellar patches; according to the age of the lesion and the amount of pigment, they could appear

walls, a dark-brown, viscous content and their diameter rarely exceed 15 cm.

Fig. 1. Endometriotic nodules as they are seen in laparoscopy

severe form of the disease.

respectively are present.

affected by the disease.

endometriosis patients should be assessed.

**2. Pathologic features of endometriosis** 

white, yellow, red, blue or brown (**Fig. 1**).

When the peritoneal lesion invades the subserosal layers it progressively leads to extensive fibrosis, wall thickening of the pelvic organs, nodule formation and distortion of the normal pelvic anatomy due to a fibrous retraction; the most severe form is the so called "frozen pelvis", that consists of a huge amount of tissue involving the retro-uterine excavation and causing an extensive infiltration of the posterior pelvis (torus uteri, uterosacral ligaments, vaginal and rectal wall).

Microscopic appearance of endometriosis is composed of endometrial glands, stroma and occasionally histiocytes, due to an inflammatory response caused by cyclic hemorrhages within the implant. In rare cases endometriosis may lack glands (stromal endometriosis) [6].
