II. Nonneoplastic Lesions
- Solitary Cysts
These represent exaggeration of the usually cystic graafian
Follicular cysts are common occurring at any age but
rarely after the onset of menopause. Many are clinically insignificant and
discovered accidentally. Occasional patient will present with a palpable
pelvic mass, abdominal pain, or evidence of estrogenic activity such as
precocious puberty in a child or menstrual irregularity in an adult due
to endometrial hyperplasia.
The cyst is thin-walled, unilocular and may be single
or multiple, unilateral or bilateral. They are usually small and only rarely
exceed 5cm. The contents vary from serous through serosanguinous to clotted
An inner layer of granulosa cells with uniform round
nuclei and little cytoplasm lines follicle cysts and an inner layer of theca
interna cells, which are small and spindle-shaped. The layers may be luteinized.
Most regress spontaneously.
These are cystic dilatations of corpora lutea and result
from delayed resolution of the central cavity of the corpus luteum. They are
less common than follicle cysts.
These cysts are clinically insignificant but patients
may present with irregular menses due to continued progesterone synthesis.
The cyst is typically unilocular usually up to 5 cm in diameter with a convoluted
yellow wall. The contents vary from serous or serosanguinous fluid to clotted
The cyst wall is composed of an inner connective tissue
layer, a middle layer of large luteinized granulosa cells and an outer layer
of small, luteinized theca interna cells.
Usually self-limited with spontaneous regression.
- Multiple Cysts
- Theca lutein cysts (Hyperreactio luteinalis)
These are multiple bilateral luteinized follicular cysts
that occur most frequently with disorders causing increase serum human chorionic
gonadotrophin levels such as pregnancy especially multiple gestation, hydatidiform
mole, choriocarcinoma, fetal hydrops, exogenous hCG treatment, clomiphene
treatment or polycystic ovary.
Abdominal symptoms are usually minimal. The condition
may be detected as a pelvic mass during any trimester, at Cesarean section,
or rarely immediately postpartum or after puerperium. Abdominal pain may
result when there is hemorrhage into cyst, torsion with infarction or rupture
with intra-abdominal hemorrhage occurs.
It is bilateral, usually causing moderately to massively
enlargement of the ovaries, which contain multiple, thin-walled cysts filled
with clear or hemorrhagic fluid. The cysts are rarely large.
The cysts show marked luteinization of the theca interna
cells and, in some cases, the granulosa cells. The ovarian parenchyma is
usually markedly edematous and frequently contains foci of luteinized stromal
The condition usually involutes during the puerperium,
postpartum period, following termination of the molar pregnancy, treatment
of the choriocarcinoma or discontinuation of hCG or clomiphene therapy.
However, this may take months to occur. Surgical intervention may be required
to remove ruptured or infarcted tissue.
- Polycystic Ovaries (Stein-Leventhal Syndrome)
Polycystic ovaries are characterized by bilaterally enlarged
polycystic ovaries, chronic anovulation and clinical manifestations due to
secretion of excess androgens. The initial abnormality resulting in the syndrome
is not known but is believed to be related to hypothalamus-pituitary dysfunction
leading to oversecretion of luteinizing hormone (LH). LH in turn stimulates
the ovary to produce excess androgens. Secretion of follicle stimulating hormone
(FSH) is inhibited resulting in repression of ovulation with follicle cyst
The usual clinical presentation is a young woman (between
15 and 30 years) with secondary amenorrhea, oligomenorrhea or irregular
menses, infertility and hirsutism. About 50% exhibit virilism and 40% are
obese. Other patients may be amenorrheic but otherwise normal.
Both ovaries are markedly enlarged and have a thickened,
fibrotic capsule with smooth pearl-white surfaces.
Polycystic ovary showing the smooth pearl-white capsular surfaces. Cysts
Microscopically, the outer portion of the cortex is
thickened and fibrotic and many follicle cysts are present in the subcapsular
cortex. The cysts have prominent outer theca interna layer, which is often
luteinized. Corpora lutea are frequently absent due to the anovulation and
occasional focal stromal luteinization is present. The chronic anovulation
results in unopposed estrogenic stimulation of the endometrium leading to
a variety of appearances ranging from mild atypical hyperplasia to well-differentiated
Polycystic ovary with two subcapsular follicular cysts.
Treatment with drugs that either induce ovulation (clomiphene
or hCG) or regulate the menstrual cycle restores fertility. Reduction of
ovarian volume by wedge resection is also successful in initiating ovulation
and restoring fertility. The endometrial changes including adenocarcinoma
regress once ovulation is achieved.
- Miscellaneous Non-cystic conditions
This refers to tumor-like enlargement of one ovary, or
occasionally both, due to accumulation of edema fluid in the stroma.
The condition typically occurs in young women who present
with abdominal or pelvic pain, menstrual irregularities and abdominal distention.
In some cases androgenic effects are seen. Partial or complete torsion occurs
in approximately 50% of cases and about 75% are right sided.
The ovary involved is enlarged, soft, fluctuant and
has a shiny, white, smooth surface. The cut surface shows a white, fibrotic
and thickened superficial cortex, which appears like a capsule, and a solid,
tan, homogeneous and gelatinous appearance with exudation of a watery fluid.
Massive ovarian edema. Swollen ovary with bulging cut surface.
There is marked diffuse stromal edema that separates
follicles and their derivatives with sparring of the superficial cortex,
which is thickened by fibrosis. Foci of luteinized stromal cells may be
This condition may be confused clinically with an ovarian
neoplasm. It has no malignant potential. Most patients have been treated
by oophorectomy but conservative management has been advocated for young
This condition is characterized by nonneoplastic proliferation
of the ovarian stromal cells.
Stromal hyperplasia is most commonly seen in postmenopausal
patients and may be associated with raised androgen levels and also with
endometrial adenocarcinoma. Stromal hyperplasia is almost always bilateral,
and may be associated with normal sized or enlarged ovaries. Cut surface
shows a homogeneous white tissue replacing the ovarian parenchyma.
Microscopically, a diffuse proliferation of plump ovarian
stromal cells within the cortex and medulla is seen.
This refers to luteinization of ovarian stromal cells
not related to follicles.
The condition is most common in postmenopausal women
in whom it is mild and clinically not significant. In young women of reproductive
age, hyperthecosis produces virilization. These women are obese, hypertensive
and have high insulin levels. In some cases estrogenic effects dominate
with endometrial hyperplasia or well-differentiated endometrial adenocarcinoma.
A few may show features characteristic of polycystic ovaries.
The ovaries are bilaterally involved and, in clinical
cases, are enlarged. The capsule is smooth and cut surface is yellow.
Histologically, nests of luteinized stromal cells are
present in the medulla and/or cortex.
The condition does not respond to clomiphene or wedge
resection of the ovary. Oophorectomy halts progressive virilization and
may also result in disappearance of the hypertension and hyperinsulinemia.
See section on uterus.
Ovarian endometriosis. Many hemosiderin-laden macrophages are present.