Female Genital Tract Cysts

Cystic diseases in the female pelvis are common. Cysts of the female genital tract comprise a large number of physiologic and pathologic cysts. The majority of cystic pelvic masses originate in the ovary, and they can range from simple, functional cysts to malignant ovarian tumors. Non-ovarian cysts of female genital system are appeared at least as often as ovarian cysts. In this review, we aimed to discuss the most common cystic lesions the female genital system.


FEMALE GENITAL TRACT CYSTS
Lesions of the female reproductive system comprise a large number of physiologic and pathologic cysts (Table  1). In order to avoid unnecessary therapy or treatment delay, in most cases, it originates in the ovary.

A. Congenital Mullerian (paramesonephric) duct anomalies
If the uterine horn becomes obstructed, it may become dilated and filled with fluid or blood products and thus mimic a cystic pelvic mass such as a non-communicating rudimentary horn with uterus unicornis (1).

B. Congenital uterine cysts such as Wolffian duct (mesonephric) cysts C. Mullerian duct cysts D. Adenomyosis
Adenomyosis is a common, nonneoplastic condi¬tion that affects menstruating women, particu¬larly those who are multiparous. In cystic adeno¬myosis, lesion size varies, and lesions may occur anywhere within the myometrium (1).

E. Cystic degeneration of intrauterine leiomyoma
An exophytic or pedunculated leiomyoma also may mimic a cystic adnexal mass if cystic degeneration is present.

F. Cystic adenomatoid tumor
Cystic changes of adenomatoid tumors are extremely rare, and this tumor is found subserosally in the posterior fundus or near the cornua. The wall of the cystic adenomatoid tumor is lined with flattened cuboidal epithelium, and this epithelial cells show immunopositivity for cytokeratin and calretinin (2).

G. Adenocystic tumor
H. Intramyometrial hydrosalpinges I. Parasitic cysts such as echinococcal cyst J. Cystic endometrial atrophy: a cystic gland dilatation combined with endometrial atrophy.
K. Cystic endometrial hyperplasia: is characterized by similar small endometrial cysts in an evenly thickened endometrium of over 5 to 6 mm.

II. CERVIX UTERI
A. Benign Diseases 1. Cervical Nabothian Cysts: A nabothian cyst is a common incidental finding that is usually located in the uterine cervix where one would find endocervical glands. Submucosal layer of the cervix is the most common location of these cysts, rarely they are seen deeply into the cervical wall. Nabothian cysts may occur by the inflammation and reparative processes of chronic cervicitis, following minor trauma or childbirth. Anechoic cystic structures are the ultrasonographic apperances of these cysts. Adenoma malignum (minimal deviation adenocarcinoma of mucinous type) or other glandular malignant cervical lesions can mimic nabothian cysts, but the latter are usually located deeper in the cervix (3,4). Generally, nabothian cysts do not require any therapy. If the lesion character is not clear and malignancy cannot be ruled out and if the patient relief from pain or a bothersome feeling of fullness in the vagina, surgical intervention is needed (3-5).

3.
Uterine Cervicitis: Uterine cervicitis is one of the most common gynecologic diseases. Symptoms or signs of acute cervicitis are a tenacious jellylike, yellow, or turbid discharge and a sensation of pelvic pressure or discomfort (3).

4.
Endocervical Hyperplasia: Located in the endocervix and superficial layer of the cervical wall. Frequently seen in women who use oral contraceptive agents and women who are pregnant or postpartum (3).

5.
Endometrioma: Endometriosis of the uterine cervix is estimated at 0.1-2.4% of all endometriotic localizations. This rare localization may be totally asymptomatic or associated with nonspecific findings like postcoital or intermenstrual bleeding. The classic strategies of diagnosis and management involve colposcopy and excision (6).

2.
Adenoma malignum: Adenoma malignum, which is also called ''minimal deviation adenocarcinoma'', is known to be a rare variant of well-differentiated mucinous adenocarcinoma of the uterine cervix, which is characterized by multilocular cystic lesions extending from the endocervical glands to the deep cervical stroma (7).

III. VAGINA AND VULVA
Benign vaginal cysts are in the majority of cases asymptomatic and are often incidentally discovered during gynecological examination for other purposes (8). True cystic lesions of the vagina originate from vaginal tissues but lesions arising from the urethra and surrounding tis-sues can present as cystic lesions in the vagina as well (9). The incidences of cyst types in decreasing order are as follows: mullerian cysts (44%), epidermal inclusion cysts (23%), Gartner's duct cysts (11%), Bartholin's gland cysts (7%) and endometriotic type (7%). Vaginal cysts are most common in the third and fourth decades (9,10). Through physical examination the lesion should be assessed for location, mobility, tenderness, definition (smooth versus irregular) and consistency (cystic versus solid) (9). Imaging by means of ultrasound, voiding cystourethrogram (VCUG), computerized tomography (CT) or magnetic resonance imaging (MRI) may be required to characterize the lesion further (9).

Mullerian Cysts
Mullerian duct cysts (MDCs) are uncommon pelvic cystic lesions, with the peak clinical incidence between the third and fourth decades of life. They usually present as small, midline, cystic masses with no symptoms and require no treatment. Occasionally, a mullerian cyst may become large enough that symptoms will warrant excision (11).

Gartner's Duct Cysts
Gartner's duct cysts are cystically dilated wolffian duct remnants and these cysts are usually located along the anterolateral vaginal wall. Gartner's duct cysts can also be associated with abnormalities of the metanephric urinary system (9).

Skene's Duct Cysts
Skene's (paraurethral) glands are bilateral, prostatic homologues located in the floor of the distal urethra. Obstruction of the ducts, presumed secondary to skenitis (most commonly gonorrhea), causes formation of cysts (9). Benign, asymptomatic; if large, may cause urethral obstruction and urinary retention (3).

Bartholin's Duct Cysts
Bartholin's glands are located bilaterally at the base of the labia minora and drain through 2-to 2.5-cm-long ducts that empty into the vestibule at about the 4 o'clock and 8 o'clock positions. Bartholin's duct cysts, the most common cystic growths in the vulva, occur in the labia majora. Two percent of women develop a Bartholin's duct cyst or gland abscess at some time in life (12,13). These benign cysts usually occur in women who are in reproductive years (12). Obstruction of the distal Bartholin's duct may result in the retention of secretions, with resultant dilation of the duct and forma-

Urethral diverticulum:
A urethral diverticulum likely forms as a consequence of infected periurethral glands or cysts rupturing into the urethral lumen. Urethral diverticula are usually found on the anterior vaginal wall along the distal two-thirds of the urethra (9).

C. EPIDERMAL CYSTS
Epidermal inclusion cysts secondary to buried epithelial fragments following episiotomy or other surgical procedures are the most common nonembryological type of vaginal cysts. These are localized, painless, and easily confused with sebaceous cysts. Most of these cysts are asymptomatic, treatment is by simple excision (9).

D. ENDOMETRIOSIS
Endometriotic cysts of the vagina and vulva are rare. Usually they mimic other, more frequently encountered lesions. Not always they have the typical symptoms of endometriosis and there diagnosis is rare determined before the surgical procedure and hystopathological examination. A detailed anamnesis, thorough clinical examination and additional methods (cystoscopic. imaging, sonographic) are needed for the diagnosis. Management consists of a surgical removal of the lesions, hormonal suppression of the ovarian function and, by all means, following up the patients for appearance of a recurrence or of a lesion de novo (14).

E. ECTOPIC URETEROCELE
A ureterocele is a cystic dilatation of the distal ureter. If present with an ectopic ureter, may present as a cystic vaginal mass.

IV. FALLOPIAN TUBES
A. Hydrosalpinx: Hydrosalpinx is a common adnexal lesion that may occur either in isolation or as a component of a complex pathologic process (eg, pelvic inflammatory disease, endometriosis, fallopian tube tumor, or tubal pregnancy) that leads to distal tubal occlusion. The most common causes of hydrosalpinx are pelvic inflammatory disease and endometriosis; among women with these condi¬tions, 8% develop hydrosalpinx (1).
B. Hematosalpinx: Hematosalpinx results from obstruction and dilatation of the fallopian tubes by blood products. It most commonly occurs in the context of endometriosis, although a tubal ectopic pregnancy, pelvic inflammatory disease, adnexal torsion, malignancy, and trauma also may cause tubal bleeding (1,15).
C. Pyosalpinx: Pyosalpinx is more likely to be bilateral, with fal¬lopian tube wall thickening, thickened uterosacral ligaments, edema of the presacral fat, and smallbowel ileus. Pelvic inflammatory disease is one of the most common causes of acute pelvic pain; it is important to differentiate pelvic inflammatory disease from ovarian malignancy, adnexal torsion, and acute appendicitis (1).
D. Inclusion Cyst: Peritoneal inclusion cyst are seen in the serosa of the tube anda re related to the frequent irritations that plague the area.

V. PARAOVARIAN CYSTS
Paraovarian cysts account for 10%-20% of all ad¬nexal masses. They arise from the mesosalpinx-the superior, free border of the broad ligament-which invests the fallopian tube. they are most common in women in the 3rd and 4th decades of life (1). Two types of paraovarian cyst

B. Paramesonephric cysts
1. Hydatid cyst of morgagni: These are a common finding at laparatomy. They are paramesonephric in origin.
They are usually small and under rare circumstances may undergo torsion.

VI. OVARIAN CYSTS
The rapid development of ultrasound technology and its routine application during gynecological examinations has led to the more frequent detection of ovarian cysts. Such cysts can be diagnosed at any age or stage of a woman's life, and detected as early as the fetal stage or as late as the postmenopause. Large cysts, multiloculi, septa, papillae and increased blood flow are all suspected signs of neoplasia.
A. Benign Ovarian Cysts 1. Follicle Cyst: Follicle cyst is found at mid cycle and its size ranges up to 25 mm.

Corpus Luteum Cyst:
3.Theca-Lutein Cyst: Theca lutein cysts or hyperstimulation cysts are associated with abnormal high levels of bHCG (human chorionic gonadotropine) as in multiple gestations, trophoblastic disease and most commonly due to pharmacologic hyperstimulation (16).

C. Malign Ovarian Cysts
Cystic ovarian tumors are classified on the basis of tumor origin as epithelial germ cell sex cord stromal tumors, unclassified and metastatic tumors ( Table 2). The subtypes of epithelial tumors include serous, mucinous, endometrioid and clear cell tumors. They represent 60% of all ovarian and 85% of malignant ovarian neoplasms and their prevalence increases with age, peaking in the sixth and seventh decade of life (16).