An epithelioid trophoblastic tumor or ETT refers to a rare gestational trophoblastic tumor. Around 110 reports in the literature associated with this tumor have been reported so far.
Gestational trophoblastic disease or GTD is also a rare group of diseases. The growth of abnormal trophoblast cells occurs inside the uterus after conception.
ETT stimulates carcinoma and can also behave in a malignant fashion. This tumor is less aggressive than choriocarcinoma resembling the placental site trophoblastic tumor. Based upon the immunohistochemical features, it appears that this gestational tumor grows from the neoplastic transformation of chorionic-type intermediate trophoblast. Death and metastasis have been reported.
An epithelioid trophoblastic tumor or ETT can be a sequela of any gestational events. It can be present in both the extrauterine and intrauterine sites. The cases of ETT are visible in women of reproductive age as abnormal vaginal bleeding, with lower levels of human chorionic gonadotropin (hCG).
Epithelioid Trophoblastic Tumor Symptoms
The epithelioid trophoblastic tumor may cause a set of signs and symptoms like other conditions. The signs and symptoms of the Epithelioid trophoblastic tumor mainly involve vaginal bleeding. Vaginal bleeding is not usually related to menstruation. The vaginal bleeding may continue for longer than usual after the delivery.
The other symptoms may include a uterus that is greater than it is during the pregnancy. The affected individuals may also experience pressure or pain in the pelvis, severe nausea, and vomiting during the expecting period. The elevated blood pressure levels along with swelling of feet and headache early are also experienced by the patients.
Other symptoms include shortness of breath, vaginal bleeding, dizziness, and an irregular or fast heartbeat caused due to anemia. The symptoms related to an overactive thyroid during this condition involve sweating, shakiness, and irregular heartbeat. It also involves; weight loss, insomnia, frequent bowel movements, and anxiety or irritability.
Epithelioid Trophoblastic Tumor Causes
Two main risk factors are more likely associated with the epithelioid trophoblastic tumor or GTD. First is the woman under 20 years of age, or women more than 35 years, and secondly, GTD in the past. Molar pregnancies affect women of all age groups; however, women under 16 and over 45 years of age are highly susceptible to developing a molar pregnancy. The Asian ethnicity is also more likely to be affected by it.
Most commonly, the duplication of a single spermatozoon that fertilizes an empty ovum takes place. Less commonly two different and separate spermatozoa fertilize an empty ovum is known as dispermic fertilization.
The partial hydatidiform moles contain triploid fetal cells with maternal haploid genes and two paternal haploid genes sets. The tumor occurs after the dispermic fertilization of a usual ovum. The malignant forms of GTD are usually quite rare. Around 50% of malignant forms of GTD develop from a hydatidiform mole.
Epithelioid Trophoblastic Tumor Prognosis
The patients treated with surgery as the first-line treatment usually had the early-stage disease and all of them survived. However, most patients treated with chemotherapy without or with surgery had FIGO stages II-IV disease (55%). The majority underwent various lines of chemotherapy; however, eleven of those patients did not survive.
The poor prognostic factors of the ETT are an interval of ≥48 months and advanced-stage disease since the antecedent pregnancy. The surgical treatment seems appropriate and well for those individuals with an early stage of tumor development along with a shorter interval. However, a well-developed or advanced-stage disease requires a combination of treatment modalities. As the Epithelioid trophoblastic tumor is rare, the treatment should be in a center with experience in GTN. Most cases have a favorable outcome; however, metastases and death occur in 25 and 10% of patients.
Epithelioid Trophoblastic Tumor Treatment
Generally, Epithelioid trophoblastic tumors (ETTs) are resistant to chemotherapy treatment. Stage I is treated with hysterectomy, whereas metastatic disease with chemotherapy and surgery. According to one report, three patients (14.3%) with FIGO stage I had non-elevated levels of β-hCG and were treated with only hysterectomy without chemotherapy. However, the remaining 18 patients (85.7%) were treated; with 1-13 cycles of multi-agent chemotherapy. EMA/ EP (etoposide, methotrexate, actinomycin-D/etoposide, and cisplatin) and EMA/CO (etoposide, methotrexate, actinomycin-D/cyclophosphamide, and vincristine) were involved. It also involved FAEV (5-fluorouracil, actinomycin-D, etoposide, and vincristine).
Among the 18 patients treated earlier with chemotherapy, only one patient going through stage IV relapsed after undergoing chemotherapy, and hysterectomy at the second hospital underwent radiotherapy and chemotherapy at the facility. However, excluding only one patient who underwent both radiotherapy and chemotherapy, the remaining 17 patients underwent surgery that included hysterectomy or resection of the isolated tumor. Conclusively, the overall mortality rate was 19.0%.