Endometrioma is the presence of tissue similar to, but distinct from, the endometrium in and sometimes on the ovary. It is the most common form of
endometriosis. Endometrioma is found in 17–44% patients with endometriosis.
More broadly, endometriosis is the presence of tissue similar to, but distinct from, endometrial tissue located outside the uterus. The presence of endometriosis can result in the formation of scar tissue, adhesions and an inflammatory reaction. It usually is a benign growth. An endometrioma is most often found in the
ovary.
This ovarian endometriosis forms dark, fluid-filled cysts.
These fluid-filled sacs can vary greatly in size and are known as endometriomas, also called "chocolate cysts". The fluid inside the cysts is thick, dark, old blood, giving it a chocolate-like appearance. It can also develop in the cul-de-sac (the space behind the
uterus
The uterus (from Latin ''uterus'', plural ''uteri'') or womb () is the organ in the reproductive system of most female mammals, including humans that accommodates the embryonic and fetal development of one or more embryos until birth. The ...
), the surface of the uterus, and between the
vagina
In mammals, the vagina is the elastic, muscular part of the female genital tract. In humans, it extends from the vestibule to the cervix. The outer vaginal opening is normally partly covered by a thin layer of mucosal tissue called the hymen ...
and
rectum.
Pathophysiology
Endometrial tissue is the
mucous membrane
A mucous membrane or mucosa is a membrane that lines various cavities in the body of an organism and covers the surface of internal organs. It consists of one or more layers of epithelial cells overlying a layer of loose connective tissue. It i ...
that normally lines the uterus. The
endometrium is richly supplied with blood and its growth is regulated by
estrogen
Estrogen or oestrogen is a category of sex hormone responsible for the development and regulation of the female reproductive system and secondary sex characteristics. There are three major endogenous estrogens that have estrogenic hormonal ac ...
and
progesterone. It consists of glandular and stroma tissue from the lining of the uterus.
When the endometrial mucous membrane is found outside of the uterus in places such as the ovaries, it causes chronic pelvic pain with intercourse and menstrual cycles.
Endometriomas can produce a toxic environment by producing estrogen, cytokines, interleukins, and other inflammatory substances, that could damage healthy endometriomal tissue. This toxic fluid content can cause dire alterations to the normal surrounding endometriotic cells, potentially impacting the embryo, the ability of an embryo to implant successfully, and the responsiveness of the endometrium. Endometrioma can potentially lead to premature ovarian failure, decreased ovarian function, or problems with ovulation.
Studies have also found that endometriomas occur two times more frequently in the left ovary (67%) than in the right one (33%), possibly due to the presence of the sigmoid colon on the left side.
Risks
Endometriomas can increase the risk of ovarian cancer in reproductive women, decrease normal ovarian function, and cause pain in the pelvis during or after periods or during sexual intercourse. Although most endometriomas are found to be benign, the possibility of malignant tumors still exists, and surgery is needed to confirm malignancy and determine what future treatment must be administered.
Another factor that endometrioma can impact is the ovarian reserve, or the number of quality follicles left in the ovary to produce viable eggs.
Ovaries with endometriomas showed significantly less follicular density as compared to healthy ovaries, leading to a decrease in fertility.
Treatment
Medication
Nonsteroidal anti-inflammatory drugs
Non-steroidal anti-inflammatory drugs (NSAID) are members of a therapeutic drug class which reduces pain, decreases inflammation, decreases fever, and prevents blood clots. Side effects depend on the specific drug, its dose and duration of ...
(NSAIDs) are frequently used first in patients with pelvic pain, particularly if the diagnosis of endometriosis has not been definitively (excision and biopsy) established. The goal of directed medical treatment is to achieve an
anovulatory
Anovulation is when the ovaries do not release an oocyte during a menstrual cycle. Therefore, ovulation does not take place. However, a woman who does not ovulate at each menstrual cycle is not necessarily going through menopause. Chronic anovula ...
state. Typically, this is achieved initially using
hormonal contraception. This can also be accomplished with progestational agents (i.e.,
medroxyprogesterone acetate),
danazol
Danazol, sold as Danocrine and other brand names, is a medication used in the treatment of endometriosis, fibrocystic breast disease, hereditary angioedema and other conditions. It is taken by mouth.
The use of danazol is limited by masculin ...
,
gestrinone
Gestrinone, sold under the brand names Dimetrose and Nemestran among others, is a medication which is used in the treatment of endometriosis. It has also been used to treat other conditions such as uterine fibroids and heavy menstrual bleeding ...
, or
gonadotropin
Gonadotropins are glycoprotein hormones secreted by gonadotropic cells of the anterior pituitary of vertebrates. This family includes the mammalian hormones follicle-stimulating hormone (FSH) and luteinizing hormone (LH), the placental/ chorioni ...
-releasing hormone agonists (
GnRH
Gonadotropin-releasing hormone (GnRH) is a releasing hormone responsible for the release of follicle-stimulating hormone (FSH) and luteinizing hormone (LH) from the anterior pituitary. GnRH is a tropic peptide hormone synthesized and releas ...
), as well as other less well-known agents. These agents are generally used if oral contraceptives and NSAIDs are ineffective. GnRH can be combined with
estrogen
Estrogen or oestrogen is a category of sex hormone responsible for the development and regulation of the female reproductive system and secondary sex characteristics. There are three major endogenous estrogens that have estrogenic hormonal ac ...
and
progestogen (add-back therapy) without loss of efficacy but with fewer hypo
estrogenic symptoms. These medications are often ineffective in treating endometriomas and any relief is short lived while taking the medications. Therapy with these agents has a large number of sometimes permanent side effects, such as hot flushes, loss of bone mass, deepening of voice, weight gain, and facial hair growth.
Surgery
Laparoscopic
Laparoscopy () is an operation performed in the abdomen or pelvis using small incisions (usually 0.5–1.5 cm) with the aid of a camera. The laparoscope aids diagnosis or therapeutic interventions with a few small cuts in the abdomen.Medlin ...
surgical approaches include
excision of ovarian adhesions and of endometriomas. Endometriomas require surgical removal and excision is considered to be superior to cyst vaporization or coagulation in terms of permanent removal of the disease and pain relief.
Surgery can sometimes have the effect of improving fertility but can have the adverse effect of leading to increases in cycle day 2 or 3 FSH for many patients. It can also pose the risk of diminishing the ovarian reserve, which could lead to post-surgery infertility. The removal of healthy ovarian tissue or compromising blood flow to the ovary are both risk factors of the surgery that could lead to detrimental affects on the ovarian reserve. However, despite the fact that there is a risk of loss of ovarian function, studies have shown the recurrence rate of endometrioma is reduced.
Recurrence rate after the surgery varies from 5 to 20%.
References
Bibliography
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External links
{{Diseases of the pelvis, genitals and breasts, state=collapsed
Noninflammatory disorders of female genital tract