Epithelioid trophoblastic tumor (ETT) is a
gestational trophoblastic disease
Gestational trophoblastic disease (GTD) is a term used for a group of pregnancy-related tumours. These tumours are rare, and they appear when cells in the womb start to proliferate uncontrollably. The cells that form gestational trophoblastic tum ...
with about 110 case reports in the literature. It is a trophoblastic tumor of neoplastic chorionic type associated with the intermediate
trophoblast
The trophoblast (from Greek : to feed; and : germinator) is the outer layer of cells of the blastocyst. Trophoblasts are present four days after fertilization in humans. They provide nutrients to the embryo and develop into a large part of the p ...
.
Signs and symptoms
* Vaginal bleeding: The most common presenting symptom is
vaginal bleeding
Vaginal bleeding is any expulsion of blood from the vagina. This bleeding may originate from the uterus, vaginal wall, or cervix. Generally, it is either part of a normal menstrual cycle or is caused by hormonal or other problems of the reproductiv ...
, which is associated with mild elevation of serum β hCG (< 2,500 IU/L)
*
Amenorrhea
Amenorrhea is the absence of a menstrual period in a woman of reproductive age. Physiological states of amenorrhoea are seen, most commonly, during pregnancy and lactation (breastfeeding). Outside the reproductive years, there is absence of menses ...
.
[http://www.pathologyoutlines.com/topic/placentaETT.html clinical features]
Morphology
Gross appearance
* There is deep infiltration of the surrounding structures by cystic hemorrhagic masses or discrete nodules.
*
Necrosis is present with white to tan-brown cut surface with hemorrhage.
*
Ulceration
An ulcer is a discontinuity or break in a bodily membrane that impedes normal function of the affected organ. According to Robbins's pathology, "ulcer is the breach of the continuity of skin, epithelium or mucous membrane caused by sloughing o ...
(common finding)
*
Fistula
A fistula (plural: fistulas or fistulae ; from Latin ''fistula'', "tube, pipe") in anatomy is an abnormal connection between two hollow spaces (technically, two epithelialized surfaces), such as blood vessels, intestines, or other hollow or ...
(common finding)
Microscopic appearance
* Nodular, well circumscribed, focal infiltrative at the periphery.
* Uniform, mononucleate tumor cells are arranged in nests and cords.
* Tumor nests are associated with eosinophilic, fibrillar, hyaline-like material.
* Extensive necrosis with irregular contours.
* Calcification (common finding)
* Metaplastic endocervical or endometrial surface epithelium into squamous-like epithelium.
Locations
Common locations are:
*Uterus
**Lower uterine segment (40%)
**Cervix (31% of cases)
*Lungs (19% of cases)
They may rarely develop in
*Vagina
*Broad ligament
*Fallopian tubes
*Other pelvic organs
[Epithelioid trophoblastic tumo]
''Pathology outlines'', August 26, 2017.
Diagnosis
Treatment
Epithelioid trophoblastic tumors (ETTs) are resistant to chemotherapy, but an immunotherapy drug called dostarlimab treats gestational trophoblastic neoplasia. ETT is a form of GTN. Stage I disease is treated with hysterectomy, while metastatic disease is treated with surgery and chemotherapy.
[Epithelioid trophoblastic tumo]
''Pathology outlines'', August 26, 2017.
Prognosis
Metastasis occur in 25% of cases and 10% die of the disease. Mitotic count of > 6/10HPF is an unfavorable prognostic factor.
[Epithelioid trophoblastic tumo]
''Pathology outlines'', August 26, 2017.
References
{{reflist
Germ cell neoplasia
Rare diseases