Tuesday, March 3, 2009
GESTATIONAL TROPHOBLASTIC DISEASE
Gestational Throphoblastic Disease (GTD) refers to series of illnesses originating in the placenta. It is a very rare disease in the United States, however, it is very common in Asia and specially in Taiwan.
Hydatiforme molar pregnancy is a benign form of these illnesses, characterized by lack of fetus. In United States, this phenomenon happens in 1 in 1000 to 2000 pregnancies. It resolves after evacuation of the uterus and does not need any other treatments.
Invasive mole: Invasive moles are the malignant counterparts of the molar pregnancies and are characterized by the invasion of inside of uterus by the molar tissue. They rarely metastasize and are curable by removal of uterus as well as chemotherapy.
Choriocarcinoma: Is the full fledge malignant variant, which metastasizes early by the blood route and is treated by chemotherapy.
Choriocarcinoma can develop following any oneof these circumstances:
• Full term pregnancy
• Pregnancy complicated by a mole
• Abortion
• Ectopic pregnancy
SIGNS AND SYMPTOMS
Any of the following signs, in association with what appears to be a normal pregnancy, could be indicative of GTD:
• Vaginal bleeding
• Out-of-proportion enlargement of the uterus
• Absent fetal movements
• Pregnancy induced hypertension in the first trimester
• Severe nausea and vomiting
Some patients present with problems that are due to metastatic disease such as:
• Cough, Shortness of breath due to Lung metastasis
• Abdominal pain, jaundice due to Liver metastasis
• Confusion, Seizure, coma due to Brain metastasis
STAGING
Purpose of staging is to determine the extent of the disease as well as its prognosis. The disease can spread to every part of the body. Spread to Brain and Liver carries a rather poor prognosis and calls for a more aggressive treatment. Routine blood tests and the following studies should be done in each patient;
• Chest X-ray
• CT scan of chest
• Head CT Scan
• Ultrasound or CT scan of abdomen and pelvis
Prognosis:
Patients are categorized into two groups:
Low Risk
• Low levels of the blood pregnancy test
• Absence of metastasis to brain or liver
• No prior history of this illness
High Risk
• High levels of the blood pregnancy test
• Metastasis to brain or liver
• Recurrence of a prior illness
TREATMENT
Hydatiforme molar pregnancy resolves after evacuation of the uterus and does not need any other treatments. Serial blood tests must be performed during and following the completion of treatments, to assure normalization the hCG levels.
Invasive mole is curable by removal of uterus, when there is no desire for having any more children, or chemotherapy. Serial blood tests must be performed during and following the completion of treatments, to assure normalization of the hCG levels.
Choriocarcinoma: Is the full fledge malignant variant, which is treated with chemotherapy. Chemotherapy is the most important measure in treatment of this disease. Surgery and removal of the uterus is indicated when there is no desire for having any more children. Surgery will shorten the duration and amount of chemotherapy. Dose and intensity of treatment is determined by the extent of the disease and the risk levels High risk patients are treated much more aggressively.
Low risk patients: Patients are normally treated with using one drug such as Methotrexate, Actinomycin D, VP-16 and are carefully followed after completion of their chemotherapy. Serial blood tests must be performed during and following the completion of treatments, to assure normalization the hCG levels.
High risk patients: These patients are at a high risk for failure and require aggressive chemotherapy with surgery or radiation therapy. Radiation therapy is used for treatment of brain metastasis. Most treatment regimes use some of the following drugs in combination: Methotrexate, Actinomycin D, VP-16 , Cytoxan, Hydroxyurea, Oncovin, Melphalan, Adriamycin, Cisplatinum and Bleomycin.