HYDATIDIFORM MOLE TAZAMMUL HUSSAIN FINAL YR MBBS
Hydatidiform mole Approximately 20% of patients with primary hydatidiform mole develop persistent GTD (invasive mole, choriocarcinoma, placental site trophoblastic tumor). Categorized as complete or partial based on gross characteristics, histologic findings, karyotype
Complete PartialGestational age 8 to16 wk 10 to 22 wkUterine sizeLarge for gestational age 33% 10%Small for gestational age 33% 65%Diagnosis by Common RareultrasonographyTheca lutein cysts 25 to 35% RareHuman chorionic >50,000 <50,000gonadotropin (mIU/mL)Malignant potential 15 to 25% <5%Metastatic disease <5% <1%
Complete mole Complete mole typically presents between 11 and 25 weeks, with an average gestational age of 16 weeks. Vaginal bleeding is the most common presenting symptom, occurring in 97% of cases, followed by excessive uterine enlargement, in 50% of cases. Severe vomiting and also pregnancy-induced HTN can occur in up to 25% of cases and hyperthyroidism in 7% of cases. In approximately 33% of patients, the uterus is small for gestational date. Ovarian enlargement caused by theca lutein cysts occurs in 25% to 35% of cases. Levels of hCG are typically above 50K mIU/mL. Ultrasonography often, but not always, discloses the diagnosis via the classic snowstorm appearance
Complete mole o Gross findings include massively enlarged, edematous villi that give the classic grape-like appearance to the placenta and lack embryonic tissue. o Pathologic features include o hydropic swelling in the majority of villi, accompanied by a variable degree of trophoblastic proliferation.
1-Trophoblastic proliferation 2-Hydropic DegenerationComplete hydatidiform mole: Microscopically Enlarged,edematous villi and abnormal trophoblastic proliferation thatdiffusely involve the entire placenta
Complete mole Chromosomal Abnormalities Most complete moles are diploid, with a 46,XX karyotype; rare examples of triploid or tetraploid moles have been reported. In most cases, all of the chromosomal complements are paternally derived. In the diploid complete mole, the XX genotype typically results from duplication of a haploid sperm pronucleus in an empty ovum that has lost its maternal chromosomal haploid set Heterozygous 10%
Incomplete mole or partial moles Incomplete mole or partial moles are diagnosed between 9 and 34 weeks of gestation. These tumors are consistently associated with embryonic/fetal tissue. Uterine size is generally small for gestational date; excessive uterine size is observed in only 4% of patients. Patients present with abnormal uterine bleeding in approximately 75% of cases. A clinical diagnosis of a missed or spontaneous abortion is made in 91% of cases of incomplete molar pregnancy. Serum hCG level is in the normal or low range for gestational age. Pre-eclampsia occurs with lower incidence (2.5%) and presents much later with a partial mole than with complete moles but can be equally severe.
Macroscopically: The molar pattern did not involve the entire placenta. Uterine enlargement in excess of gestational age is uncommon. Theca-lutein cysts are rare Fetal or embryonic tissue or amnion Microscopically: The enlarged, edematous villi and abnormal trophoblastic proliferation are slight and focal and did not involve the entire villi. There is a scalloping of chorionic villi Fetal or embryonic or fetal RBCs
Partial Hydatidiform Mole Scalloping of chorionic villiTrophoblastic proliferation are slight and focal
Incomplete mole orpartial moles Chromosomal Abnormalities. Karyotype of partial moles most frequently shows triploidy (69 chromosomes), with two paternal sets and a maternal chromosome complement. The chromosomal complement is XXY in 70% of cases. The abnormal conceptus in these cases arises from the fertilization of an egg with a haploid set of chromosomes either by two sperm, each with a set of haploid chromosomes, or by a single sperm with a diploid 46XY complement.
INVASIVE MOLE Invasive mole is the most common sequela of hydatidiform mole, representing 70% to 90% of cases of persistent GTD. The disorder occurs when hydropic chorionic villi are present within the myometrium, its vascular spaces, or at distant sites. This lesion has been known as chorioadenoma destruens, penetrating mole, malignant mole, and molar destruens. Up to 20% of invasive moles metastasize to extrauterine pelvic and distant sites (e.g., lungs, vagina, vulva, or broad ligament).
INVASIVE MOLE • Pathologic Features. Grossly, invasive moles present as an erosive, hemorrhagic lesion extending from the uterine cavity into the myometrium. Invasion can range from superficial penetration to extension through the wall, with uterine perforation and life-threatening hemorrhage. Molar vesicles are often grossly apparent. The diagnostic feature of invasive mole is the presence of molar villi and trophoblast within the myometrium or at an extrauterine site. Lesions at distant sites are usually composed of molar villi confined within blood vessels, without invasion into adjacent tissue.
Diagnosis and Management of MolarPregnancy Workup : The pathologic diagnosis of a hydatidiform mole is made from dilation and curettage (D&C) performed for an incomplete abortion or because of suspicion of hydatidiform mole based on clinical findings (physical examination, hCG levels, ultrasonography). The following tests should be performed preoperatively: Quantitative serum hCG level Complete blood count (CBC) Prothrombin time, partial thromboplastin time Comprehensive metabolic panel with renal and liver function tests Blood type and screen [Rh-negative patients must be given RhO (D) immune globulin (RhoGAM)] Chest radiograph
Diagnosis and Management of MolarPregnancy… Treatment : The primary treatment for hydatidiform mole is suction D&C. The following steps should be taken before suction D&C: Stabilization of medical complications Full operating room support in a hospital setting Large-bore intravenous (IV) access with possible central line monitoring Determination of active blood type and blood screen Induction of regional or general anesthesia Initiation of oxytocin drip (during D & C) Uterine evacuation is accomplished with the largest plastic cannula that can be safely introduced through the cervix. IV oxytocin is begun after the cervix is dilated and suction is initiated, and is continued postoperatively for several hours.
Diagnosis and Management of MolarPregnancy…. Follow-Up. After the surgical evacuation of a hydatidiform mole, all patients should be monitored as follows hCG level should be measured 48 hours after evacuation. hCG level should be determined weekly until results are normal for 3 consecutive weeks, then monthly until results are normal for 6 to 12 consecutive months
Pelvic examinations should be performed to monitor the involution of pelvic structures (e.g., ovaries, uterus) and to aid in early detection of metastasis. Repeat chest radiograph if the hCG titer plateaus or rises.
Effective contraception is recommended for the entire interval of hCG follow-up testing, namely 6 to 12 months. During surveillance, oral contraceptive pills, contraceptive patches, and injectable progestins are typically recommended as safe and reliable birth control. Although barrier methods decrease the risk of transmission of sexually transmitted diseases, in practice the potential for contraceptive failure is greater with diaphragms and condoms than with hormonal methods. Barrier methods are therefore not the first choice for contraception. An intrauterine device should not be inserted until the patient achieves normal gonadotropin levels because of the risk of uterine perforation. Because of increased risk of a second mole in subsequent pregnancies, all future pregnancies should be evaluated by ultrasonography early in their course. The magnitude of the risk of recurrent partial moles is approximately 1% to 2%
Medical Complications of Hydatidiform Mole Common complications include anemia, infection, hyperthyroidism, pregnancy-induced hypertension or pre-eclampsia, and theca lutein cysts. Anemia : A hemoglobin of less than 10 g/dL, seen in 50% of patients with complete moles and results from excessive vaginal bleeding Pre-eclampsia: occurs in approximately 25% of cases and presents with the signs and symptoms of pre-eclampsia seen in nonmolar pregnancies [hypertension (HTN), proteinuria, edema]. Hyperthyroidism : Seven percent of patients with complete moles present with hyperthyroidism, with clinical findings of tachycardia, HTN, and tachypnea. These patients should receive beta-sympathetic blockade before induction of anesthesia to prevent thyroid storm, which can be precipitated by surgery itself. Both hyperthyroidism and pregnancy-induced hypertension usually abate promptly after evacuation of the molar pregnancy and may not always require specific therapy. Theca lutein cysts (cysts >6 cm) are observed in 50% of patients and result from hCG stimulation. These cysts may require 2 to 4 months to resolve completely. Persistent cysts warrant appropriate workup and
Pulmonary distress : is observed in 2% of patients. Frequently, it occurs at the time of evacuation of a mole in patients with marked uterine enlargement. Patients present with chest pain, shortness of breath, tachypnea, tachycardia, and hypoxemia. These signs and symptoms usually resolve within 72 hours of institution of supportive measures. In general, pulmonary complications should be treated aggressively. Interventions, including pulmonary artery catheter monitoring and assisted ventilatory support, may be required.
Gynecology and Obstetrics (FIGO) Staging of Gestational Trophoblastic DiseaseStage Tumor characteristicsStage I Strictly confined to uterusStage II Extension outside uterus but limited to pelvic structuresStage III Extension to lungsStage IV All other metastatic sites Each stage is further divided into A, B, or C as follows: A = no risk factor Risk factors that affect staging include (a) B = one risk factor present human chorionic gonadotropin level C = two risk factors present >100,000 mIU/mL and (b) duration of disease >6 months from termination of the antecedent pregnancy.
World Health Organization (WHO) Prognostic Scoring IndexScore 0 1 2 4Age <40 yr ≥40 yrAntecedent Mole Abortion Term TermpregnancyInterval (months) <4 4 to 6 7 to12 >12from antecedentpregnancySerum-hCG level <103 103 to 104 104 to 105 ≥105(mIU/mL)ABO blood group A, O BLargest tumor size <3 3 to 5 ≥5(cm)Metastases Lung, vagina Spleen, kidney Gastrointestinal tract Brain, liverNumber of 0 1 to 4 5to 8 >8metastasesPrevious none One drug Two or more drugschemotherapyThe total score is obtained by adding the individual prognostic factors. Scores from 0-6 are categorised as low risk, while a score of 7 or higher is high risk .
High-risk Metastatic Disease. Stages II and III disease may be deemed high risk based on a WHO prognostic score . All stage IV disease is considered high risk. Chemotherapy : For patients with high-risk metastatic disease, the recommended treatment is combination chemotherapy with etoposide, MTX, actinomycin D, cyclophosphamide (Cytoxan), and vincristine sulfate (EMA-CO) The chemotherapy is administered until three negative test results for hCG are achieved in 3 consecutive weeks or until intolerable side effects occur. After the normalization of hCG levels, an additional two courses should be given as consolidation therapy.