Histopathological and clinical features of molar pregnancy

OBJECTIVE

To analyse own set of molar pregnancies and to develop clinically relevant procedures.

TYPE OF STUDY

Review article with analysis of own data.

SETTINGS

Department of Pathology 3rd Faculty of Medicine, Charles University, Faculty Hospital Královské Vinohrady, Prague; Department of Obstetrics and Gynecology 3rd Faculty of Medicine, Charles University, Faculty Hospital Královské Vinohrady, Prague.

INTRODUCTION

The study monitors the decrease of laboratory values of beta-subunit of hCG gonadotropin (beta-hCG) after evacuation of partial and complete hydatidiform moles in a set of 45 partial and 46 complete moles. Two case reports of invasive moles.

RESULTS

In cases of partial hydatidiform moles there was complete regression of beta-hCG in all cases, 89% regressed in six weeks, none of the women showed no subsequent elevation after reaching negativity. In cases of complete hydatidiform moles the decrease was less gradual, the negativity after six weeks was confirmed in 78%, three complete moles became malignant.

CONCLUSION

The decrease of beta-hCG after molar pregnancy termination is variable. Even if in cases of complete hydatidiform moles the risk of malignization after reaching negativity is low, beta-hCG checks are recommended at monthly intervals for 6 months. Correct diagnosis of complete mole and its differentiation from partial mole can be achieved using immunohistochemistry - p57 antibody.

Differences in total human chorionic gonadotropin immunoassay analytical specificity and ability to measure human chorionic gonadotropin in gestational trophoblastic disease and germ cell tumors

OBJECTIVE

To determine the ability of several radioimmunoassays and commercial two-site immunoassays to detect the first World Health Organization International Reference Reagents (IRRs) for 6 defined human chorionic gonadotropin (hCG) variants and to compare their performance in measuring hCG in sera from patients with gestational trophoblastic disease (GTD) and germ cell tumors (GCTs) of the testis or ovary.

STUDY DESIGN

The reactivity of the different assays with the 6 IRRs together with the current fourth International Standard (IS, 75/589) was tested using 5 commercial two-site assays as well as 2 competitive polyclonal radioimmunoassays (RIAs) and a competitive monoclonal immunoassay. Individual samples from 41 patients (19 GCT and 22 GTD) with high circulating levels of hCG (range, 718-6,055,000 IU/L) were diluted and measured using the various immunoassays.

RESULTS

The results of 4 GCT patient samples varied markedly among the assays, including 1 sample that was grossly underestimated by 3 of the commercial assays.

CONCLUSION

Comparison of each assay's reactivity to the variant isoforms revealed that recognition of the isoforms was highly variable, particularly for hCGbeta and hCGbeta core fragment (hCGbetacf).

Japanese trial for classification of gestational trophoblastic disease

OBJECTIVE

To evaluate the clinical usefulness of the Japanese Diagnostic Score to differentiate choriocarcinoma clinically without histologic findings from persistent gestational trophoblastic disease (GTD).

STUDY DESIGN

We reviewed the clinical records and histologic reports on all 809 patients with persistent GTD treated with surgery and chemotherapy in Japan. There were 347 cases of choriocarcinoma and 462 cases of invasive mole with histologic confirmation. We retrospectively applied the Japanese Diagnostic Score to all patients for detection of choriocarcinoma in persistent trophoblastic disease.

RESULTS

The sensitivity of the score for choriocarcinoma was 92.2%. The specificity was 93.5%. This retrospective study showed that the accuracy of this scoring system to differentiate true malignant choriocarcinoma clinically from both low risk and high risk gestational trophoblastic neoplasia without histologic findings was 92.9%.

CONCLUSION

Our trial to differentiate choriocarcinoma clinically from persistent GTD without histologic findings using a unique scoring system was successful. Proper management in the early stages strongly influences the outcome of these diseases. This scoring system should be very useful in comparing the incidence and survival rate of choriocarcinoma between nations.

Partial hydatidiform mole

A case of partial hydatidiform mole is presented, occurring in a young primiparous woman after natural conception. She presented with incomplete miscarriage. Histological diagnosis of partial mole was made. Failure of beta HCG to fall resulted in the start of chemotherapy. WHO scoring placed her in low risk group. In spite of the low risk, she required third line chemotherapy for complete eradication of disease.

[Regression of hCG in various types of molar pregnancies--clinical course and prognosis]

OBJECTIVE

To evaluate spontaneous regression curves of hCG serum positivity in patients with surgically treated molar pregnancies. Comparison of complete, partial and invasive mole. The study should result in optimalisation of follow up criteria of molar pregnancies in respect to their potential malignant change.

DESIGN

Retrospective comparative clinical study.

SETTING

Obst. Gyn. Dpt., Oncogynecology div., 2nd Medical Faculty, FNM, Charles University Prague, Pathology Dpt., 2nd Medical Faculty, Institute of Biology and Medical Genetics.

METHODS

Evaluation of spontaneous regression curves of serum hCG levels in 104 molar pregnancies. 46 patients with partial hydatiform mole, 48 patients with complete hydatiform mole, 10 patients with invasive mole. Serum hCG levels were detected by radioimunoassay (RIA) in the first period and imunochemoluminisent assay (LIA) in the second period. Regression curves of hCG positivity in particular moles were statistically evaluated by Fischer test and t-test.

RESULTS

There is statistically significant difference in spontaneous regression of hCG positivity in different types of molar pregnancies. Recommended criteria for gestational trofoblastic disease (GTD) diagnosis and follow up are fully applicable in clinical practice. There is exception in partial hydatiform moles, where plateau in hCG regression does not necessarily implicate chemotherapy in patient with good compliance.

CONCLUSION

Early diagnosis of GTD predominantly due to the widespread use of ultrasonography changes classical clinical features of molar pregnancies. Spontaneous regression in hCG positivity in serum is more rapid in patients with partial hydatiform mole, slower in complete hydatiform mole and invasive mole. There is no significant change in malignant potential regarding early detection and treatment.

A clinical trial on diagnostic scoring system of choriocarcinoma and invasive mole in Vietnam

OBJECTIVES

The aim was to discriminate preoperatively invasive mole (IM) and choriocarcinoma (CC) in patients with gestational trophoblastic neoplasm (GTN) for early and satisfactory treatment in Vietnam.

METHODS

In 1990, 122 patients with GTN treated at TUDU Hospital were retrospectively analysed to make a differential diagnosis between CC and IM by using the JSOG scoring system and these results were later compared with postoperative histopathological findings. Furthermore, to raise the predictive diagnostic value for CC, the authors modified the JSOG system and devised a scoring system of TUDU hospital which results were compared with that of the JSOG ones. From the end of 1990 to March 1993, in 151 patients with GTN who underwent surgery, preoperative and postoperative diagnoses of CC and IM were prospectively compared using the JSOG and the modified scoring system. The comparative data were statistically analysed using the t-test, chi 2 test and Fisher test. The sensitivity, specificity, and the positive and negative predictive value, and false positive and false negative were calculated and compared. RESULTS RETROSPECTIVE STUDY: In making a predictive diagnosis of 122 patients with findings of trophoblastic tumors, the authors found some differences in possibility of CC of the following subfactors: latent period, primary lesion, pulmonary metastases, metastases except pulmonary metastases and hCG rerise. So, a modified scoring system of TUDU hospital was devised.

PROSPECTIVE STUDY

Of 151 Vietnamese patients with GTN using the JSOG scoring system and the modified system, a diagnostic probability in 108 cases predicted choriocarcinoma by JSOG scoring system was 61%, while that of invasive mole in 43 cases was 62.8%. Accordingly, the false positive rate for invasive mole of 64 cases predicted choriocarcinoma was 38.9%. According to the modified scoring system, of 75 patients predicted choriocarcinoma, 69 patients were histologically confirmed choriocarcinoma. Therefore, the diagnostic specificity was high (94.20%) and the false positive rate was low (5.3%), while of 76 patients predicted invasive mole, 13 patients were histologically diagnosed as choriocarcinoma. Accordingly, the false negative rate was low (13.1%).

CONCLUSION

The modified JSOG scoring system is of more diagnostic value in the preoperative differentiation between CC and IM in Vietnam.

Usefulness of granulocyte colony-stimulating factor on neutropenia in patients of invasive mole and choriocarcinoma

The effect of human granulocyte colony stimulating factor (hG-CSF) was investigated on the proliferation of choriocarcinoma cells in vitro. No growth-stimulating effect was observed. Then, 22 patients with invasive mole and 9 patients with choriocarcinoma who received combination chemotherapy were treated with hG-CSF when white blood cell counts decreased below 2,000/mm3. The duration of neutropenia was reduced significantly by 3-4 days with the use of hG-CSF. No side effects were observed. These results indicate safety and usefulness of hG-CSF as an adjunct to chemotherapy in the treatment of gestational trophoblastic disease.

[Clinical evaluation of ultrasonography in diagnosis of the early invasive hydatidiform mole]

The consecutive uterine changes of the B ultrasonic scan were observed in 41 cases with invasive hydatidiform mole, which compared with the uterine changes in 10 controls who had induction of labor in second trimester. It was found that B ultrasonic scan was very useful technic in diagnosis of invasive mole. The time when the serum hCG titers fell to normal was earlier than the time of B scan reversed during treatment. Therefore, the B scan of uterus is of value in early diagnosis and therapeutic quide of invasive mole.

Serum SP1, hPL and beta-hCG levels in trophoblastic diseases

Serum SP1 (pregnancy specific beta 1 glycoprotein), hPL (human placental lactogen) and beta-hCG (beta-human chorionic gonadotropin) in patients with choriocarcinoma, invasive mole, and hydati-diform mole were determined by radioimmunoassay (RIA), and compared with those in normal males, non-pregnant women and normal pregnant women in order to evaluate the clinical significance of SP1, hPL and beta-hCG determinations. Serum SP1 levels at the time of admission were highest in hydatidiform mole (5.1 +/- 0.6 micrograms/L) and lowest in choriocarcinoma (0.5 +/- 0.3 micrograms/L). Serum hPL levels were 68.2 +/- 9.7 ng/L in hydatidiform mole and 26.4 +/- 8.3 ng/L in choriocarcinoma. Serum SP1 and hPL levels in trophoblastic diseases were lower than in normal pregnancies (SP1 11.5 +/- 5.1 micrograms/L, hPL 216.8 +/- 48.1 ng/L). SP1/beta-hCG ratios were less than 1.5 in 4/43 (9.3%) cases of hydatidiform mole and 17/19 (89.5%) cases of invasive mole and choriocarcinoma. The beta-hCG/hPL ratios were below 15 in 35/43 (81.4%) cases of hydatidiform mole and 4/19 (21.1%) malignant trophoblastic diseases. The prognosis after operation and chemotherapy was favourable if patient's SP1 and beta-hCG levels gradually decreased.

[Evaluation of serum ferritin in female genital neoplasms]

Serum ferritin concentrations of 50 normal women and 90 patients with neoplasms of female genital tract were determined by radioimmunoassay. The mean value of serum ferritin in 23 cases of ovarian carcinoma was 402.04 micrograms/L, significantly higher than that of normal subjects and patients with benign genital neoplasms. Serum ferritin levels in patients with endometrial carcinoma, endometrial stromal sarcoma, and benign genital neoplasms were significantly higher than that of the normal subjects. There was a positive correlation between the serum ferritin level and the clinical stage of ovarian carcinoma. The serum ferritin determination is useful in the diagnosis, differential diagnosis and prognosis of ovarian cancers.

Gestational trophoblastic tumours following initial diagnosis of partial hydatidiform mole

11 patients registered with an initial diagnosis of partial hydatidiform mole (PHM) subsequently required chemotherapy for a gestational trophoblastic tumour. In a retrospective review by histopathological examination and measurement of DNA ploidy, the diagnosis was confirmed as PHM in 5 cases and revised to complete hydatidiform mole in 4; in 2 cases there was no evidence of a molar pregnancy. 4 of the patients with PHM had no other known pregnancy before the gestational trophoblastic tumour and in 2 of these patients the tumour was diagnosed histologically as choriocarcinoma. Not all patients in whom PHM was diagnosed at referring hospitals proved to have the condition. Although the risk of a patient with PHM requiring chemotherapy for gestational trophoblastic tumour is of the order of 1 in 200, compared with 1 in 12 after a complete mole, there is no justification for excluding a patient from follow-up after the evacuation of a PHM.

Elevated sera levels of SP-1 induced by chemotherapy in patients with metastatic gestational trophoblastic diseases

6 patients with invasive mole and 5 patients with choriocarcinoma were treated from 1983 till 1986. Serum samples were analyzed by simultaneous determining of pregnancy-specific beta-1-glycoprotein (SP-1) using enzyme-linked immunosorbent assay (ELISA) and beta subunit of human chorionic gonadotropin (beta-hCG) using Serono radioimmunoassay kit. In 2 patients with metastatic gestational trophoblastic disease (MGTD) SP-1 peaks were found during chemotherapy. In patients with MGTD with normalized beta-hCG levels a repeated, temporary elevation of isolated SP-1 levels was observed within some months following chemotherapy. After the last isolated peak of SP-1 the pulmonary metastases disappeared. This phenomenon was interpreted as a consequence of the oncolytic process in the affected tissue. In 1 patient with nonmetastatic choriocarcinoma SP-1 ELISA pseudoreaction was found. To recognize these pseudoreactions, a control plate with nonimmunized rabbit IgG was used, simultaneously with SP-1 determinations.

[Molar pregnancy (primary or recurrent?)]

A peculiar case of gestational trophoblastic disease is described. A 24 year old female with former history of three molar pregnancies, spontaneous abortion and anembryoic pregnancy was admitted because of a newly diagnosed hydatiform mole (ex novo). After uterine curettage followed by a low oral dose of methotrexate (0.5 mg/kg/day) for five days. The HCG levels determined in plasma by beta-HCG- radioinmmunoassay, became negative until four months of follow3 up. An intrauterine device was installed. She resumed HCG positivity a year later and a histerectomy was performed. A post-surgical diagnosis of invasive mole was made. Since the possibility of intercurrent pregnancy was lowered by the presence of a intrauterine device, we assumed that trophoblastic transformation into an invasive mole adopted a sort of dormant period before its resurge (resurrection) independently either from curettage of chemotherapy.

Radioimmunoassay of the serum free beta-subunit of human chorionic gonadotropin in trophoblastic disease

We developed a RIA specific for the free beta hCG employing anti-beta hCG monoclonal antibody 1D12. This RIA was highly sensitive to free beta hCG; the minimum detectable concentration was 0.4 ng/ml. alpha hCG, LH, beta LH, and FSH had little effect in the assay; the cross-reactivity of hCG was about 4%. Using this RIA, we measured serum free beta hCG concentrations in 38 normal pregnant women and 72 untreated patients with 3 types of trophoblastic disease: hydatidiform mole (n = 15), invasive mole (n = 29), and choriocarcinoma (n = 28). All of these samples were simultaneously assayed for hCG by RIA. In normal pregnant women, serum hCG changed as pregnancy progressed, but serum free beta hCG was not detected at any time. In contrast, serum free beta hCG was measurable in the majority of patients with trophoblastic disease. Strong correlations were found between the concentration of free beta hCG and that of hCG in each type of trophoblastic diseases. The mean free beta hCG to hCG ratio was lowest for hydatidiform mole and highest for choriocarcinoma, and the difference between the ratios in these 2 groups was statistically significant. Serial measurements in 7 patients with trophoblastic disease failed to reveal remarkable changes in the free beta hCG to hCG ratio throughout their clinical course. We conclude that the production of free beta hCG increases with the immaturity of the trophoblastic cell, and the degree of differentiation of trophoblastic cells may be reflected by the free beta hCG to hCG ratio.

Serum relaxin in patients with invasive mole, choriocarcinoma and persistent trophoblastic disease

Human chorionic gonadotropin (hCG) is considered to be one of the factors which regulate relaxin secretion in humans. Serum immunoreactive relaxin levels are increased and are detectable by radioimmunoassay both in normal and molar pregnancy. Circulating hCG levels are increased in trophoblastic disease. In the present study, relaxin and hCG levels were sequentially measured in patients with invasive mole, choriocarcinoma and persistent trophoblastic disease. Serum relaxin levels were detectable by radioimmunoassay in these patients before treatment, though they were significantly lower than in normal pregnancy. The corpus luteum of pregnancy is the main source of circulating relaxin in normal pregnancy. The existence of a corpus luteum was confirmed in the 2 patients who underwent laparotomy. Consequently, the corpus luteum may also be the main source of circulating relaxin in trophoblastic disease. Parallel changes in hCG and relaxin levels were observed during the courses of trophoblastic disease. The finding suggests that relaxin secretion is dependent on hCG stimulation in trophoblastic disease in the presence of corpus luteum.

Invasive mole

A case of persistent trophoblastic disease with resistance to chemotherapy is presented. The value of continued and frequent serum hCG measurements in such cases is discussed as well as the indications for performing hysterectomy.

Serum human placental lactogen (HPL) levels in patients with intact hydatidiform mole

Serum human placental lactogen (HPL) levels in forty cases of intact hydatidiform mole were measured by radioimmunoassay. The HPL values were generally lower than normal pregnancies of the corresponding period of gestation. However, normal and occasionally higher than normal values were observed in a few cases. Serum HPL level alone is of some clinical use in the diagnosis of hydatidiform mole. When combined with human chorionic gonadotropin (HCG), a low HPL/HCG ratio for the corresponding period of amenorrhoea is a useful index in the diagnosis of hydatidiform mole.

Endocrine assay in chorionic tumors

Gestational chorionic tumors represent a rare biologic system for three reasons: They are a genetic mixture of both male and female; they are unusually responsive to chemotherapy with a high cure rate; and they always secrete hCG, which acts as a reliable cell marker with which to diagnose, to monitor drug therapy, and to follow-up to ensure continued remission. Nongestational chorionic tumors characteristically share only the latter unique attribute. For this reason, endocrine assays, particularly the measurement of hCG, play a vital role in the management of patients with these tumors. However, as the tools with which we work improve, and our understanding increases, it is quite likely that other tumors will be found to make substances that are similarly specific and reliable so as to be utilized in the same way. Already there are tests such as alpha-fetoprotein and carcinoembryonic antigen that are beginning to serve such a role but are not as specific as is hCG. Our experience with chorionic tumors has given us a valuable opportunity to develop techniques to be used for other tumor systems when reliable cell markers become available. When this time comes, we should be able to look forward to improved survival rates, hopefully approaching those obtained with chorionic disease.