They originate as focal hyperplasia of the basalis and develop into localized
overgrowths of endometrial tissue covered by epithelium. Endometrial polyps
are most common in women between 40 and 50 years.
The polyp may cause irregular bleeding. It may be broad-based and sessile,
pedunculated or attached to the endometrium by a slender stalk. Most occur
in the fundus and extend downwards. The size is variable from 1mm to a mass
that fills the endometrial cavity. Occasionally a polyp may protrude through
the external os. Grossly it is smooth, red or brown and dark red when infarcted.
Endometrial polyp attached to the fundus.
Composed of glands of variable size and shape, fibrotic stroma and thick-walled
blood vessels. The relative amounts of the 3 components vary considerably
from polyp to polyp.
Endometrial polyp. Many dilated blood vessels are present.
Endometrial polyps are benign with no malignant potential but malignant tumors
may be found in them. When this occurs the prognosis is more favorable provided
the tumor has not extended beyond the base.
Question: What other lesions may present as a "polyp" in
Leiomyoma is a benign tumor of smooth muscle origin. It is the most common
neoplasm of the female genital tract and probably in women and is more common
in black than white women.
Clinical and gross appearances
Patients may present with irregular bleeding, pelvic pain, pelvic mass, infertility.
The tumor is estrogen responsive and may undergo rapid increase in size during
pregnancy. In about 70% of patients it is multiple. Leiomyoma may be located
anywhere in the myometrium.
Submucosal tumors are overlain by compressed endometrium, may be pedunculated
and occasionally protrude though the cervix.
Intramural tumors, the most common, lie within the myometrium.
Subserosal fibroids lie beneath the serosal covering of the uterus
or are pedunculated and attached to the serosa. Pedunculated ones may undergo
torsion and infarction or loose their connection to the uterus and become
attached to another pelvic organ forming a "parasitic leiomyoma".
The tumors appear as well circumscribed, spherical, dense and firm-to-hard
masses with whorled, tan-white cut surfaces.
Leiomyoma. Note whorled cut surface.
Microscopically, there are interlacing bundles of smooth muscle cells with
collagenous stroma between bundles.
Leiomyoma composed of interlacing fibers of bland smooth muscle.
Degenerative changes may be seen. These take the form of:
Atrophy the tumor reduces in size at menopause or after pregnancy
following drop in estrogen level.
Hyaline change (hyalinization) histologic appearance in which the
neoplastic smooth muscle cells and collagen fibers loose their detail and
appear to fuse and take on a homogeneous, acellular, glassy eosinophilic appearance.
Usually occurs as the tumor "ages".
Myxoid and cystic change myxoid change results from marked increase
in mucoid ground substance such that the affected areas come to resemble myxoid
tissue of the umbilicus. Liquefaction occurs after extreme myxoid change leading
to formation of cysts.
Calcification common in menopausal women. Circulatory deprivation
leads to precipitation of calcium salts within the tumor. Usually occurs in
areas of hyalinization.
Septic Infection may follow necrosis of the center due to circulatory
Red (carneous) venous thrombosis and congestion with interstitial
hemorrhage may occur, most commonly in pregnancy. This is usually accompanied
by pain, which may produce a clinical picture of acute abdomen.
This is a benign tumor with no appreciable malignant potential (incidence
of malignant transformation is 0.1-0.5%). It may cause anemia from heavy bleeding
in non-pregnant women, or urinary or bowel obstruction (subserosal or parasitic
Question: What type of anemia may be caused by uterine leiomyoma?
Question: What complications may arise in pregnancy?