Sister chromatid exchange and chromosome breakage in complete hydatidiform moles

Women with complete hydatidiform moles (CHM) are at a 10% risk for developing persistent trophoblastic disease or choriocarcinoma. We studied sister chromatid exchange (SCE) as a prognostic indicator for malignancy in peripheral blood lymphocytes (PBL) from women with CHM and their husbands, but found no differences from normal control couples. SCE levels in cultured tissue derived from 11 CHM (avg. 7.9) and 2 choriocarcinomas (avg. 6.8) were not significantly different from those of 8 normal skin fibroblast cultures (avg. 7.8). These same tissues were then examined for chromosome breakage which was significantly higher for CHM (0.48/cell) and choriocarcinoma (0.87/cell) than normal fibroblasts (0.33/cell). Chromosome breaks occurred at 50-60% known fragile sites and at 50-55% of cancer breakpoints. Whereas SCE was only associated with 13% of breaks in the three tissues, half of these were at known fragile sites. Our results suggest that SCE is not an indicator of malignancy in PBL or cultured cells from CHM or choriocarcinoma and that the level of SCE is not elevated in CHM or choriocarcinoma. However, our results confirm the increased breakage seen in the latter two tissues which may represent general DNA instability predisposing to choriocarcinoma and its accompanying chromosomal rearrangements.

Uterine leiomyomas: cytogenetic and histologic profile

OBJECTIVE

The main purpose of this study was to determine whether there is any correlation between the cytogenetic abnormalities and histology in uterine leiomyomas.

METHODS

A total of 93 benign uterine leiomyomas were included in the study. The majority (88 of 93) were classified as typical benign leiomyomas, four as cellular, and one as atypical symplastic.

RESULTS

A normal chromosome complement (46,XX) was observed in approximately 50% of the cases (41 of 93). Seventeen leiomyomas did not grow sufficiently in culture to yield cells for chromosome analyses. Of the 35 cases with clonal abnormalities, 28 could be divided into four major subgroups, each representing one of the most common abnormalities observed, such as those of chromosomes 1, 7, and 13, and t(12;14).

CONCLUSIONS

Our findings indicate that approximately 50% of leiomyomas show clonal abnormalities, which can be subdivided into four different major categories; four of five (80%) of the atypical leiomyomas showed clonal chromosome abnormalities, which in one case were complex. The results indicate that different specific chromosome abnormalities may characterize the same tumor type.

Genetics and biology of human ovarian teratomas. III. Cytogenetics and origins of malignant ovarian germ cell tumors

This report presents cytogenetic data on three cases of malignant ovarian germ cell tumors. All were diagnosed as malignant teratoma; case 1 with yolk sac elements; case 2 with elements of endodermal sinus tumor, embryonal carcinoma, and choriocarcinoma; and case 3 with yolk sac elements and embryonal carcinoma. Metaphase cells from each tumor, and normal tissue from the host, were karyotyped and scored for centromeric heteromorphisms in an attempt to determine the mechanism of origin. The karyotypes were 79,XXX,+1,+3,-6,+8,+12,+14,-15,+17, +20,+21,+22;49,XX,+8,+12,+22; and 48,XX,+3,+14, respectively. The analysis of centromeric heteromorphisms and DNA fingerprints of host and teratoma using the M13 probe revealed that one case originated from a germ cell before the first meiotic division. Normal host tissue was not available in case 2, but several centromeric markers were heterozygous in the tumor, indicating either meiosis I error or complete failure of germ cell meiosis. In the third case the centromeric heteromorphisms that were heterozygous in the host appeared to be homozygous for certain chromosomes and heterozygous for others in the tumor. These results suggest that germ cell teratomas could arise by the fusion of two ova.

Inversion (X)(p22q13) in a uterine leiomyoma

We report a case of uterine leiomyoma which showed a karyotype 46,X,inv(X)(p22q13) as the only clonal change in most of the cells. A few cells had an additional del(7), though del(7) has been found to be a primary change in leiomyomas. These findings indicate that the abnormality involving the X chromosome and particularly Xp22 can be considered as a primary chromosomal abnormality. We discuss the findings together with few reports of cases involving chromosome X in leiomyomas.

Subgroups of uterine leiomyomas based on cytogenetic analysis

Chromosomes from 39 cases of benign uterine leiomyomas were studied. Consistent chromosomal abnormalities were detected in 15 cases (38.5%). Abnormalities involving chromosomes 12 and 14 with or without additional chromosomal changes were found in five cases (12.8%). Deletion of chromosome 7 was detected in five cases; in three cases (7.6%), this was the only abnormality present. Complex translocations involving X, 5, and 14 as well as X, 3, and 14 were observed in one case each. Insertion of a portion of chromosome 4 to chromosome 1, deletion involving chromosome 3, and nonreciprocal translocation between chromosomes 14 and 15 were observed in one case each. Monosomy 22, with a derived chromosome 14, was observed in one case. Trisomy 7 was also identified in one case. The structural and numeric abnormalities involved chromosomes X, 1, 2, 3, 4, 5, 6, 7, 9, 10, 12, 13, 14, 15, and 22. A normal 46,XX stem line with one or two abnormal cells was observed in 20 cases. Only normal karyotypes were obtained in the remaining four cases. A review of the literature and the results of our study indicate that uterine leiomyomas may be divided into eight groups based on cytogenetic analysis.

Deletion of chromosome 13 in leiomyomas of the uterus

We report two cases of leiomyomas of the uterus with a deletion of the long arm of chromosome 13. To our knowledge this cytogenetic abnormality as a single change has not been reported previously. One of our cases showed a del(13)(q14q32) and the other a del(13)(q13q33). We discuss the cases and compare our findings with previous ones reported in the literature.

Associated leukemia and mixed germ cell tumor in a patient with gonadal dysgenesis

A 16-year-old phenotypic female developed acute myeloblastic leukemia with a fulminant course very shortly after surgery and chemotherapy for a mixed germ cell tumor of the ovary. The karyotype (46, XY, 47, XY + 8) suggested de novo rather than therapy-associated leukemia. The relationship between germ cell tumors and leukemia, their common yolk sac derivation and the role of the Y chromosome are discussed. The idea that XY gonadal dysgenesis may be familial also is discussed.

Nonrandom cytogenetic changes in leiomyomas of the female genitourinary tract. A report of 35 cases

Cytogenetic analysis of short-term cultures from 35 leiomyomas of the female genitourinary tract showed abnormal karyotypes in 14 cases. In 11 of 14 aberrant tumors, normal cells were also observed. Structural changes were most frequent, resulting in modal chromosome numbers in the diploid range. Our data confirm preferential breakpoint clusters at 7q, 12q14-15, and 14q23-24, mainly resulting from consistent, specific chromosome rearrangements such as t(12;14)(q14-15;q23-24) and del(7)(q21) or del(7)(q22q32). Together with previously published cases, we describe trisomy 12, ring chromosomes, and monosomy 22 as new additional recurrent findings in myomas. Statistical analyses of possible coherencies between tumor karyotype (abnormal versus normal) and clinicopathologic data, as well as age of the patients, menopausal status, and tumor size showed no correlations.

Squamous cell carcinoma in situ arising in an ovarian mature cystic teratoma. Report of one case with histopathologic, cytogenetic, and flow cytometric DNA content analysis

A squamous cell carcinoma in situ arose in an ovarian mature teratoma (ie, dermoid cyst) in a 62-year-old woman. Flow cytometric DNA content analysis of paraffin-embedded in situ carcinoma showed a normal DNA content with moderate to high proliferative activity (S-phase fraction estimate, 16% to 18%). Cytogenetic analysis of the in situ cancer and the benign cystic portion of the tumor revealed a 46,XX karyotype. In addition, the benign cystic portion of the tumor revealed homozygous chromosomal heteromorphisms, compared with heterozygous markers found in peripheral blood lymphocytes. These results show that this squamous cell carcinoma in situ was euploid and suggest that the mature cystic teratoma was derived from a single germ cell after meiosis I.

The physical organization of the human immunoglobulin heavy chain gene complex

Two dimensional DNA electrophoresis (2D-DE) was used to map the variable (VH) region of the human heavy chain immunoglobulin gene cluster. Seventy-six VH gene segments were mapped to specific SfiI, BssHI and NotI fragments by 2D-DE. We have determined that a common insertion/deletion polymorphism of 80 kb, involving three VH gene segments, occurs in the VH region. The physical map suggests that the evolution of the human IGH gene complex involved duplication of blocks containing different VH families. This physical map will allow comparison of the usage of VH loci in human ontogeny with their proximity to the CH region. Knowledge of the germline repertoire of a particular DNA source studied in essential as the number of the dispersed VH gene segments of VH families, especially of the VH5 family, is variable. 2D-DE, as illustrated here for the IGH gene cluster, has general application in the development of large scale physical maps of gene and repeat families.

Genetics and biology of human ovarian teratomas. I. Cytogenetic analysis and mechanism of origin

One hundred and two benign, mature ovarian teratomas and two immature, malignant teratomas were karyotyped and scored for centromeric heteromorphisms as part of an ongoing project to determine the chromosomal karyotype and the genetic origin of ovarian teratomas and to assess their utility for gene-centromere mapping. Karyotypic analysis of the benign cases revealed 95 46,XX teratomas and 7 chromosomally abnormal teratomas (47,XXX, 47,XX,+8 [two cases], 47,XX,+15, 48,XX,+7,+12 91,XXXX,-13 [mosaic], 47,XX,-15,+21,+mar). Our study reports on the first cases of tetraploidy and structural rearrangement in benign ovarian teratomas. The two immature cases had modal chromosome numbers of 78 and 49. Centromeric heteromorphisms that were heterozygous in the host were homozygous in 65.2% (n = 58) of the benign teratomas and heterozygous in the remaining 34.8% (n = 31). Chromosome 13 heteromorphisms were the most informative, with 72.7% heterozygosity in hosts. The cytogenetic data indicate that 65% of teratomas are derived from a single germ cell after meiosis I and failure of meiosis II (type II) or endoreduplication of a mature ovum (type III); 35% arise by failure of meiosis I (type I) or mitotic division of premeiotic germ cells (type IV).

Genetics and biology of human ovarian teratomas. II. Molecular analysis of origin of nondisjunction and gene-centromere mapping of chromosome I markers

Chromosomal heteromorphisms and DNA polymorphisms have been utilized to identify the mechanisms that lead to formation of human ovarian teratomas and to construct a gene-centromere map of chromosome 1 by using those teratomas that arise by meiotic nondisjunction. Of 61 genetically informative ovarian teratomas, 21.3% arose by nondisjunction at meiosis I, and 39.3% arose by meiosis II nondisjunction. Eight polymorphic marker loci on chromosome 1p and one marker on 1q were used to estimate a gene-centromere map. The results show clear linkage of the most proximal 1p marker (NRAS) and the most proximal 1q marker (D1S61) to the centromere at a distance of 14 cM and 20 cM, respectively. Estimated gene-centromere distances suggest that, while recombination occurs normally in ovarian teratomas arising by meiosis II errors, ovarian teratomas arising by meiosis I nondisjunction have altered patterns of recombination. Furthermore, the estimated map demonstrates clear evidence of chiasma interference. Our results suggest that ovarian teratomas can provide a rapid method for mapping genes relative to the centromere.

Rearrangement of band 10q22 in leiomyoma and leiomyosarcoma of the uterus

Cytogenetic analysis of a uterine leiomyoma from a 56-year-old woman revealed an interstitial deletion of chromosome 10, del(10)(q22q24), as the only chromosomal abnormality. Band 10q22 was also rearranged in a previously reported leiomyosarcoma of the uterus showing a t(10;17)(q22.1;p13) as the only change. These findings provide an additional example in soft tissue tumors for involvement of the same chromosomal regions in benign and malignant proliferation of cells from the same lineage.

Correlation between pathologic and ultrasound findings in first trimester spontaneous abortions

We compared the pathologic and ultrasonographic findings of 31 first trimester spontaneous abortions to determine the benefits of such studies. The ultrasound diagnoses included empty gestational sac (n = 11), intrauterine fetal death (n = 11), abortion in progress or incomplete abortion (n = 8), and live embryo (n = 1). Two subgroups of empty sacs were identified by pathologic examination. Embryonic development appeared to be more advanced in one group as indicated by the presence of embryonic red blood cells (RBC's) in the placental vessels. Although an embryo or fetus was identified more frequently by sonar than by pathologic examination, we were able to diagnose developmental anomalies in small embryos that current ultrasound equipment cannot resolve. Such anomalies were identified even in the presence of fetal heart activity. Pathologic examination was also informative when heavy bleeding obscured the contents of the uterine cavity to sonar and was thus supplementary of a suboptimal ultrasound examination. Placental examination proved to be reliable in assessing gestational age at the time of embryonic/fetal death. There was a good correlation between RBC morphology and sonographic measurement of crown-rump length. First trimester ultrasound and pathologic examination of the embryo and placenta are informative and complement each other.

Chromosomal rearrangement in choriocarcinoma cell lines

Malignant trophoblastic cells from four choriocarcinoma cell lines were evaluated in detail using Q, G, and C banding at various passages. The modal chromosome numbers for BeWo, DoSmi, ElFa, and Jar were 73, 71, 77, and 72, respectively. All the four tumor cell lines exhibited extensive chromosomal rearrangements with several consistent marker chromosomes in each. The majority of these markers have not been previously recognized in this malignancy. Rearrangements of chromosomes 1, 7, 9, 10, and 12 were noted in all four cell lines, but abnormalities of chromosomes 1 and 12 were not consistently present in ElFa and Jar, respectively. Telomeric associations were observed in two cell lines involving chromosomes 11 and 21 as well as chromosomes 3 and 12, resulting in two consistent marker chromosomes. A total of 86 breakpoints were involved in the consistent rearrangements observed in all four cell lines. Most of these breakpoints were located on chromosomes 1, 3, 9, 13, 12, 7, and 21, in order of frequency.

Rapid RFLP screening using DNA from complete hydatidiform moles

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Deletion of terminal portion of 6q: report of a case with unusual malformations

We present the necropsy findings of a 21-week-gestation male fetus with deletion of the terminal portion of long arm of chromosome 6 [46,XY,del(6)(q23----qter)]. Major anomalies include intrauterine growth retardation, facial anomalies, nuchal cyst, scoliosis, bilateral diaphragmatic hernias, persistent common atrioventricular canal, absent olfactory bulbs and agenesis of corpus callosum. In aberrations of chromosome 6q, patients usually have psychomotor retardation, somatic growth failure, and facial anomalies; nuchal cyst and bilateral diaphragmatic hernias have not yet been described.

Content and organization of the human Ig VH locus: definition of three new VH families and linkage to the Ig CH locus

We present a detailed analysis of the content and organization of the human immunoglobulin VH locus. Human VH genes representing five distinct families were isolated, including novel members belonging to two out of three of the known VH gene families (VH1 and VH3) as well as members of three new families (VH4, VH5, and VH6). We report the nucleotide sequence of 21 novel human VH genes, many of which belong to the three new VH gene families. In addition, we provide a preliminary analysis of the organization of these gene segments over the full extent of the locus. We find that the five multi-segment families (VH1-5) have members interspersed over nearly the full 1500-2000 kb of the VH locus, and estimate that the entire heavy chain locus covers 2500 kb or less. Finally, we provide the first report of the physical linkage of the variable and constant loci of a human Ig gene family by demonstrating that the most proximal known human VH segments lie within 100 kb of the constant region locus.

Cytogenetics of trophoblasts from complete hydatidiform moles

The risk of developing choriocarcinoma following a complete hydatidiform mole (CHM) is 2000-4000 times greater than the risk following a normal pregnancy. To understand more fully the increased susceptibility of the molar trophoblast to malignant transformation, we separated the trophoblastic cells from the stromal cells in 14 complete moles and cultured them for cytogenetic analysis. The numerical and structural abnormalities found were compared with those found in the trophoblasts from normal pregnancy and malignant choriocarcinoma cell lines. The percentage of polyploid cells was 2.8 times greater in molar trophoblasts than in normal trophoblasts. Although we found no consistent chromosomal abnormality in the molar trophoblasts, these cells were significantly more vulnerable to chromosomal breakage than the molar fibroblasts, normal trophoblasts, normal fibroblasts, and maternal decidual cells. Out of a total of 103 breakpoints observed in 338 cells, 42 coincided with known fragile sites, 18 with the location of protooncogenes, 27 with breakpoints reported in other neoplasia, and 18 with breakpoints found in four choriocarcinoma cell lines. The chromosomes in choriocarcinoma cell lines have hypotetraploid mode and many structural rearrangements. Our results suggest that the genetic instability found in the molar trophoblasts may be responsible for progressive karyotypic changes and greater susceptibility to malignant transformation.

Hydatidiform mole: parental chromosome aberrations in partial and complete moles

The relationship between parental constitutional chromosome abnormalities and the development of hydatidiform mole was evaluated in series from four institutions. Karyotype analysis was performed on blood samples from 237 patients with a pathological diagnosis of complete mole and 217 of their spouses. One patient was found to have a constitutional balanced translocation, t(11;18), while one spouse was found to have a balanced translocation, t(4;20). Among 125 patients with partial mole and 106 of their spouses, one male was found to be a translocation carrier, t(13;14). No significant increase in the frequency of translocations in the parents of complete moles was found in any of the series considered separately or together. Data from the combined series show no evidence of constitutional parental chromosome aberrations as an aetiological factor in the development of molar pregnancies.

Immunocytochemical localization of chorionic gonadotropin, placental lactogen, and placental alkaline phosphatase in the diagnosis of complete and partial hydatidiform moles

Complete hydatidiform moles (CHMs) and partial hydatidiform moles (PHMs) represent different clinicopathologic entities with characteristic morphologic and cytogenetic findings. In the absence of cytogenetic data, the histologic distinction between these lesions and abortuses showing hydropic swelling (AHS) may be difficult. An immunocytochemical study analyzing the distribution of human chorionic gonadotropin (hCG), human placental lactogen (hPL), and placental alkaline phosphatase (PlAP) in CHMs, PHMs, and AHS was undertaken to determine whether the expression of these trophoblastic proteins might assist in the differential diagnosis. A total of 24 CHMs, 22 PHMs, and 13 AHS were selected on the basis of established morphologic criteria. Thirty-four specimens of abortuses without hydropic swelling and normal placentas, ranging from 6 to 24 weeks gestational age, were similarly analyzed. The immunocytochemical localization of the three trophoblastic proteins, predominantly in syncytiotrophoblast (ST), was scored using a semiquantitative scoring system. In CHMs hCG is widely distributed and PlAP is patchily distributed in ST regardless of the gestational age, whereas hPL tends to increase with increasing gestational age. In contrast, in PHMs hPL is more widely distributed in ST compared with CHMs regardless of gestational age, while PlAP increases with increasing gestational age; in PHMs the distribution of hCG is markedly less than in CHMs except early in the first trimester when the staining patterns are similar. The different patterns of distribution of hCG, hPL, and PlAP may reflect differences in the pathobiology of trophoblast in CHMs and PHMs and appear to be useful in the differential diagnosis of these conditions.

Hydatidiform mole: cytogenetically unusual cases and their implications for the present classification

Unusual observations in hydatidiform moles are of clinical importance as well as of theoretical interest when the present subgrouping into partial or complete moles is evaluated, particularly in view of the more malignant potential of the latter. The purpose of the present review is to summarize, update, and evaluate information on moles with unusual karyotypes or origins. The important factor in the evolution of partial or complete moles appears to be the ratio of maternal to paternal chromosomes and not the ploidy of the tissue. Complete hydatidiform moles develop from androgenetic conceptions while partial hydatidiform moles develop from those conceptions in which the number of paternal sets of chromosomes exceeds the number of maternally derived sets. Rare cases inconsistent with this concept emphasize the value of examining morphologic features, cell ploidy, and genetic markers when one is attempting to classify hydatidiform moles.

A hypervariable region at the D19S11 locus

The polymorphic locus D19S11 consists of four closely linked RFLPs: alpha, beta, delta, and gamma on chromosome 19p13.2----19cen, revealed by subclones p13-1-82 and p13-2-21 from cosmid 1-13. Here, we report that p13-1-25, an additional subclone of c1-13, reveals three insertion/deletion RFLPs, alpha, epsilon, and phi, at the D19S11 locus. In situ hybridization of p13-1-25 to metaphase chromosomes from a carrier of a 19/X translocation with a breakpoint near the centromere confirms localization of D19S11 to 19p. Studies with hydatidiform moles have generated assignments of specific restriction fragments to these three loci, and genotypic studies in three-generation families have indicated that they are closely linked. Loci alpha (also detected by p13-1-82) and phi each have but two common alleles, whereas epsilon has at least 33 alleles, including a null allele. Fifty unrelated individuals tested displayed unique fragment patterns on Taq I blots probed with p13-1-25. Applications of this probe include monitoring loss of chromosome 19 during tumorigenesis, monitoring engraftment of donor bone marrow after transplantation, testing for paternity, and mapping disease genes on chromosome 19.

Tetraploid partial hydatidiform moles: two cases with a triple paternal contribution and a 92,XXXY karyotype

In the course of a systematic study of cytogenetics, morphology, and clinical follow-up of hydatidiform moles we encountered two unusual cases of partial hydatidiform moles each with a 92,XXXY karyotype. Previously reported cases of tetraploidy, of 92,XXXX or 92,XXYY karyotype, resulted from a failure of the first mitotic division of a normal zygote. This is to our knowledge the first report of tetraploidy with XXXY sex chromosomes. Study of chromosomal heteromorphisms, isozymes, and restriction fragment length polymorphisms reveal that both present cases resulted from a combination of a haploid ovum with three haploid sets of paternal chromosomes either by the mechanism of trispermy (involving three separate haploid spermatozoa) or through dispermy (involving one haploid and one diploid sperm). Both cases resembled closely partial moles in their morphology; one gave a highly typical clinical picture while the other was recognized at an early voluntary abortion. Partial moles are ordinarily triploids of nearly always diandric constitution that evince focal villous swelling with cistern formation and focal trophoblastic hyperplasia. The findings here presented point to an association of molar phenotype with an excess of paternal over maternal haploid sets.

Effect of hydatidiform molar vesicular fluid on blood coagulation

The effect of fluids from both complete and partial hydatidiform moles on blood coagulation was determined. Coagulation was evaluated with use of the one-stage prothrombin time and the activated partial thromboplastin time. These studies demonstrated that the fluids shortened the activated partial thromboplastin time but not the prothrombin time. The use of plasmas deficient in factors V, VIII, IX, and X as substrate showed that the fluids shortened the activated partial thromboplastin time in the presence of plasmas deficient in factors VIII and IX but had no effect on the activated partial thromboplastin time in the presence of plasmas deficient in factors V and X. These data suggest that hydatidiform mole fluids possess procoagulant activity and that the activation of blood coagulation takes place at the level of factor X. These findings may have relevance to the placental and decidual focal necrosis seen in molar pregnancies, especially those of the complete variety.

Human chorionic gonadotropin levels in complete and partial hydatidiform moles and in nonmolar abortuses

The rates of regression of human chorionic gonadotropin (hCG) in patients with complete hydatidiform moles, partial hydatidiform moles, and nonmolar abortions were compared. No difference in rates of regression was found among the three groups, but levels of hCG immediately after uterine evacuation were significantly higher in the group with complete hydatidiform moles. Differences in the time required for hCG levels to become undetectable were attributed to the difference in the degree of initial elevation of hCG.

Morphologic anomalies in triploid liveborn fetuses

Analysis of the morphologic features of 43 complete and 11 mosaic triploid infants delivered at or after 22 weeks of gestation revealed, in addition to well-delineated gross features, a number of new or previously little emphasized histopathologic features. These included testicular Leydig cell hyperplasia, increased levels of hematopoiesis, and ovarian, adrenal, and pulmonary hypoplasia. Some of these findings appeared to be linked to partial hydatidiform mole replacing the normal placenta, which was present in about 70 per cent of the triploid cases. It is important to recognize the breadth of the triploidy spectrum, which ranges from near normalcy to multisystem involvement, and to pay special attention to the placenta. The importance of correct morphologic diagnosis of triploidy is stressed in view of the fact that its occurrence apparently does not prejudice the future reproductive performance of the parents.

Dispermic origin and clinical outcome of three complete hydatidiform moles with 46,XY karyotype

Three new cases of complete, classic hydatidiform mole with a 46,XY karyotype are described. They originated by dispermy as demonstrated by chromosome and enzyme analyses. Levels of human chorionic gonadotropin decreased to normal spontaneously within a short time, indicating a benign course in these three cases. Of a total of 18 cases reported to data, postoperative clinical information was available for 10 patients. Two of these 10 patients had a malignant course with lung metastases. It is of theoretical and clinical importance to establish the magnitude of the risk of malignancy for hydatidiform mole with a 46,XY karyotype.

The clinicopathologic profile of the partial hydatidiform mole

Having delineated the complete and the partial hydatidiform moles as 2 separate entities on the basis or morphology and cytogenetics, the authors studied 201 molar pregnancies at the Magee-Womens Hospital in an attempt to characterize the clinicopathologic profile of the partial mole syndrome. This was done mainly by comparison and contrast with the established and more familiar syndrome of the classic complete mole. The partial mole syndrome displays most of the pathologic and clinical features of the classic mole and seems to represent a milder, dilute version of the latter. This applies to placental morphology, to the fate of the embryo/fetus, and to human chorionic gonadotropin (hCG) levels as well as to the incidence and severity of clinically persistent trophoblastic disease. Preeclampsia can be equally severe in both syndromes, but tends to occur later in patients with partial mole. No metastatic disease was encountered in association with partial moles and no case of overt choriocarcinoma has yet been described. The occurrence of trophoblastic disease (as determined by postoperative hCG titers) following partial moles requires further inquiry, including study of the pathology of the underlying lesion(s), which remain virtually unexplored.

Ultrasonography of partial hydatidiform mole

Partial hydatidiform mole differs from complete mole by its focal distribution, its slower transformation, the presence of an embryo or fetus, and the triploid karyotype. Nineteen pathologically proved cases are presented. Partial mole can be diagnosed by a combination of the following sonographic findings: (a) greatly enlarged placenta relative to the size of the uterine cavity, (b) cystic spaces within the placenta ("molar placenta"), which may not always be present, (c) an amniotic cavity (gestational sac), either empty or containing amorphous fetal echoes, and (d) a well-formed but growth-retarded fetus, either dead or alive.

The syndromes of hydatidiform mole. II. Morphologic evolution of the complete and partial mole

Hydatidiform moles studied with respect to cytogenetics and morphologic constitution were divisible into two syndromes: (1) complete, classical mole giving a 46 XX karyotype and (2) partial mole with an ascertainable embryo/fetus, dead or alive, giving a triploid karyotype. The complete moles undergo early and total hydatidiform change from edema to central cistern formation, the embryos proper having perished before the establishment of a functioning circulation. Trophoblastic hyperplasia is conspicuous and the connection of this group to chorioncarcinoma is well established. In the partial moles there is a slow hydatidiform change that affects only some of the villi, but which seems to follow along the same lines as in complete moles. There is focal moderate trophoblastic hyperplasia, villous "trophoblastic inclusions" (that appear in triploids only), and maze-like central cisterns in the later cases. The partial mole, 46 XX, partakes of morphologic characteristics of both main syndromes and may represent an unusual syndrome of its own. The two main syndromes can now be distinguished morphologically and the question of the association of the partial mole with chorioncarcinoma has now to be further studied.

The syndromes of hydatidiform mole. I. Cytogenetic and morphologic correlations

Cytogenetic and morphologic analysis of 23 hydatidiform moles allowed the division into at least two syndromes: (1) the syndrome of complete (classical) mole is without an ascertainable embryo/fetus, gives a diploid karyotype, and manifests a progressive fluid engorgement of the villi as well as a gross, haphazardly distributed trophoblastic hyperplasia; (2) the syndrome of partial (incomplete) mole has an ascertainable fetus (alive or dead), gives a triploid karyotype, and exhibits a slowly progressing hydatidiform swelling in the presence of functioning villous capillaries that spares many villi; trophoblastic immaturity is constant and focal hyperplasia is inconspicuous but present. A single case of diploid mole with unusual morphologic features, complete with a fetus, may herald yet another syndrome. Human chorionic gonadotropin levels were initially high in practically all cases. There was no malignant trophoblastic disease in this small series, but a plea is made that partial moles be followed carefully in order to establish their relation to choriocarcinoma.