The pathology of intermediate trophoblastic tumors and tumor-like lesions

Pseudo-myometrial thinning in placental site trophoblastic tumors: a case series with multiparametric MRI

PURPOSE

Placental site trophoblastic tumor (PSTT) is a rare form of gestational trophoblastic neoplasm with few previous imaging case reports. We report multiparametric MRI findings in four cases of PSTT with special emphasis on the "pseudo-myometrial thinning" underlying the tumor.

METHODS

We reviewed multiparametric MRI and pathologic findings in four cases of PSTT from four institutions. Signal intensity, enhancement pattern, margins, and location of the tumors were evaluated, and myometrial thickness underlying the tumor and normal myometrial thickness contralateral to the tumor were measured on MRI. The myometrial thickness underlying the tumor was also measured in the resected specimen and compared with the myometrial thickness measured on MRI using the Friedman test.

RESULTS

All tumors showed heterogeneous signal intensity on T1-weighted imaging, T2-weighted imaging (T2WI), and diffusion-weighted imaging. Three of the four tumors had a hypervascular area on dynamic contrast-enhanced (DCE) MRI. A hypointense rim on T2WI and DCE-MRI was seen in all tumors. All tumors protruded into the uterine cavity to varying degrees and extended into the myometrium close to the serosa. The myometrial thickness underlying the tumor measured on MRI (median thickness, 1.2 mm) was significantly thinner than that measured on pathology (median thickness, 9.5 mm) and normal myometrial thickness contralateral to the tumor on MRI (median thickness, 10.3 mm) (P = 0.02), and there was no significant difference between the latter two.

CONCLUSIONS

The thickness of the myometrium underlying the tumor on MRI was approximately one tenth of the thickness on pathology. Thus, the tumors appeared to have almost transmural invasion even when pathologically located within the superficial myometrium. This "pseudo-thinning" of the underlying myometrium and the hypointense rim on MRI could be caused by focal compression of the myometrium by the tumor, possibly due to the fragility of the myometrium at the placental site.

Triaging and Evaluation of Products of Conception in Abortions and Post-Partum Hemorrhage

The proper evaluation of abortion specimens and placentas from stillbirth and post-partum cases is important for adequate clinical care of post-abortion and post-partum patients. The following topics will be reviewed: (1) the importance of evaluation of both fetal and placental tissue in first trimester abortions to confirm an intrauterine pregnancy versus an ectopic pregnancy; (2) the clinical history associated with an abortion specimen or retained products of conception (POC) influences how the pathologist should triage the specimen; (3) the criteria for diagnosis of a molar pregnancy, which is critical for clinicians to know which patients need follow-up; (4) the utility of genetic studies for both diagnosis and appropriate follow-up of the patient; and (5) the pathologic evaluation of specimens from patients with post-partum hemorrhage for placenta accreta spectrum and subinvolution of maternal vessels.

Primary epithelioid trophoblastic tumor of the lung: A case report

ABSTRACT

Primary epithelioid trophoblastic tumor (ETT) of the lung is exceedingly rare. Only about three cases have been reported in Pubmed and worldwide literature. We presented a case of multiple primary ETT of the lung occurring in a 33-year-old Chinese female patient. Comprehensive physical examinations revealed no evidence of a primary lesion on the uterus or cervix uteri. Microscopic examination of the tumor demonstrated ETT of the lung, which was confirmed by immunohistochemical staining and declining level of beta-human choriogonadotropin ( β -HCG) after the operation. Our case revealed that the ETT can occur in the lung and should be considered when a female had a tumor of lung with increasing β -HCG.

The Rare of the Rarest: Placental Site Trophoblastic Tumor, Epithelioid Trophoblastic Tumor, Atypical Placental Site Nodule

BACKGROUND

Epithelioid Trophoblastic Tumor (ETT) and Placental Site Trophoblastic Tumor (PSTT) are two of the rarest GTNs that share certain features at diagnosis and management. Atypical Placental Site Nodule (APSN) is a relatively new entity considered as a premalignant lesion.

OBJECTIVES AND METHODS

The aim of this review was to summarize the main characteristics of each of these entities, their diagnostic features, and their treatment's standard of care including fertility-sparing treatments.

OUTCOME

This study provides a thorough review of ETT, PSTT, and APSN.

CONCLUSIONS

The reader will gain an insight view of these rare tumors arising from the intermediate trophoblast.

Extrauterine epithelioid trophoblastic tumour and its somatic carcinoma mimics: short tandem repeat genotyping meets the diagnostic challenges

AIMS

While epithelioid trophoblastic tumour (ETT) primarily arises from the uterus, cases have been increasingly documented at extrauterine sites, originating from an ectopic gestation or presenting as a metastatic tumour, leading to the major differential diagnosis of somatic carcinoma with trophoblastic differentiation. The precise separation of a gestational trophoblastic tumour from its somatic carcinoma mimics is highly relevant and crucial for patient management and prognosis.

METHODS AND RESULTS

We summarise the clinicopathological and molecular features of four challenging epithelioid malignancies presenting at extrauterine sites, with ETT as the main differential diagnosis. All four tumours demonstrated histological and immunohistochemical features overlapping between a somatic carcinoma and an ETT, combined with inconclusive clinical and imaging findings. Serum beta-hCG elevation was documented in two cases. Short tandem repeat (STR) genotyping was performed and was informative in all cases. The presence of a unique paternal allelic pattern in the tumour tissue confirmed the diagnosis of ETT in two cases with an initial consideration of either somatic carcinoma or suspicion of a gestational trophoblastic tumour. The presence of matching genetic profile with the patient's paired normal tissue was seen in two other cases (both initially considered as ETT), confirming their somatic origin, including one metastatic triple-negative breast carcinoma and one primary lung carcinoma.

CONCLUSIONS

Diagnostic separation of ETT at an extrauterine site from its somatic carcinoma mimics can be difficult at the histological and immunohistochemical levels. STR genotyping offers a robust ancillary tool that precisely separates ETT from somatic carcinomas with trophoblastic differentiation.

Reconsideration of the Diagnostic Criteria for an Atypical Placental Site Nodule Comparing Typical Placental Site Nodule of the Uterus: A Report of Two Cases

Placental site nodules (PSNs) are non-neoplastic remnants of chorionic-type intermediate trophoblastic cells from a previous gestation that form a well-defined single nodule or multiple nodules in the uterine and extrauterine sites. As the cases of PSNs transformed into gestational trophoblastic tumors were described in the literature, "atypical placental site nodules" (APSNs) have been considered as putative transitional lesions between PSNs and gestational trophoblastic tumors. Although histologic criteria and cutoff point of Ki-67 proliferation index for differentiating an APSN from a typical PSN have not been clearly defined, nodules larger than 5 mm with increased cellularity, a corded or nested appearance, marked nuclear atypia, increased mitotic activity, and an increased Ki-67 proliferation index (>5% or >8%) of intermediate trophoblastic cells seem to be accepted as diagnostic criteria for APSNs. However, some of the criteria, including lesion size and histologic features of the trophoblastic cells in the nodule are not only subjective but have features inherent of the intermediate trophoblastic cells of the fetal membrane and a typical PSN. We thought that it is not reasonable to consider them as diagnostic features of APSNs, if not associated with cellular proliferation. We present 2 cases of incidentally identified PSNs that were larger than 10 mm in size with a corded or nested arrangement of trophoblastic cells, which could have been categorized as APSNs according to the currently proposed criteria to discuss whether the currently proposed diagnostic criteria for APSNs are appropriate.

Acquired uterine arteriovenous malformation-Does it really exist? A case report

Acquired arteriovenous malformations (AVM) of the uterus can cause life-threatening vaginal bleeding and are associated with previous pregnancy, abortion or pelvic trauma. The pathophysiology is not well understood and the diagnosis is usually made by greyscale ultrasound often with nonspecific imaging findings, hence making it difficult to establish a correct diagnosis and therefore also the true incidence. However, case reports have previously described a connection between AVM formation and placental invasive disorders. In this report we demonstrate a case of a woman diagnosed with an AVM by ultrasound, presenting with menorrhagia after a termination of pregnancy, resulting in an emergency hysterectomy where subsequently a vascular malformation was found in conjunction with a remnant of a placenta increta and a placental site nodule. We hence suggest the hypothesis that these conditions are part of the same pathological process in the spectrum of abnormal invasive placental disorders, and that in the setting of previous trophoblastic processes, vascular malformations may mimic AVMs and ought not in fact to be considered as true AVMs.

Gestational trophoblastic disease: an update

Gestational trophoblastic diseases (GTD) encompass a spectrum of rare pre-malignant and malignant entities originating from trophoblastic tissue. This updated review will highlight important radiological features, pathology and classification, and provide insight into the clinical management of these uncommon disorders. There is a wide geographic variation with the incidence of hydatidiform mole varying between 0.57 and 2 per 1000 pregnancies. The use of ultrasound (US) in the management of early pregnancy symptoms and complications has positively impacted the earlier detection of these diseases and resulted in diminished morbidity. Additional imaging modalities are reserved for problem solving or assessment of pulmonary manifestations of molar pregnancy. Having an awareness of their pleomorphic sonographic presentation and additional pathology that can mimic GTD is critical to avoiding pitfalls. Histologic and molecular analysis further aids in differential diagnosis. Gestational trophoblastic neoplasia (GTN) is inclusive of all malignant GTDs, and arises after 20% of molar pregnancies but can also be seen with non-molar gestations. Biochemical monitoring with human chorionic gonadotrophin is imperative for ongoing monitoring and surveillance and allows early detection of this entity. Doppler US is used for confirmation of diagnosis with magnetic resonance imaging (MRI) reserved for problem solving or assessment of myometrial invasion. This is of heightened relevance in patients undergoing surgical management. Cross sectional imaging is reserved for patients in the setting of GTN for the purposes of staging, prognostication and in the setting of recurrent disease. This may require a combination of computed tomography, MRI and positron emission tomography. Doppler US can provide insight into chemotherapeutic response/predict resistance in patients with GTN. As our understanding of these disorders evolves, there has been maturation in management options with a shift from traditional chemotherapy to innovative immunotherapy, particularly in the setting of resistant or high-risk disease.

Molecular Analyses of Chorionic-Type Intermediate Trophoblastic Lesions: Atypical Placental Site Nodules are Closer to Placental Site Nodules Than Epithelioid Trophoblastic Tumors

Gestational trophoblastic diseases derived from the chorionic-type intermediate trophoblast include benign placental site nodule (PSN) and malignant epithelioid trophoblastic tumor (ETT). Among PSNs, the World Health Organization classification introduced a new entity named atypical placental site nodule (APSN), corresponding to an ETT precursor, for which diagnostic criteria remain unclear, leading to a risk of overdiagnosis and difficulties in patient management. We retrospectively studied 8 PSNs, 7 APSNs, and 8 ETTs to better characterize this new entity and performed immunohistochemical analysis (p63, human placental lactogen, Cyclin E, and Ki67), transcriptional analysis using the NanoString method to quantify the expression of 760 genes involved in the main tumorigenesis pathways, and RNA sequencing to identify fusion transcripts. The immunohistochemical analysis did not reveal any significant difference in Cyclin E expression among the 3 groups (P = .476), whereas the Ki67 index was significantly (P < .001) higher in ETT samples than in APSN and PSN samples. None of the APSN samples harbored the LPCAT1::TERT fusion transcripts, in contrast to 1 of 6 ETT samples, as previously described in 2 of 3 ETT samples. The transcriptomic analysis allowed robust clustering of ETTs distinct from the APSN/PSN group but failed to differentiate APSNs from PSNs. Indeed, only 7 genes were differentially expressed between PSN and APSN samples; CCL19 upregulation and EPCAM downregulation were the most distinguishing features of APSNs. In contrast, 80 genes differentiated ETTs from APSNs, establishing a molecular signature for ETT. Gene set analysis identified significant enrichments in the DNA damage repair, immortality and stemness, and cell cycle signaling pathways when comparing ETTs and APSNs. These results suggested that APSN might not represent a distinct entity but rather a transitional stage between PSN and ETT. RNA sequencing and the transcriptional signature of ETT described herein could serve as triage for APSN from curettage or biopsy material, enabling the identification of cases that need further clinical investigations.

Case Report: Tubal Atypical Placental Site Nodule

Placental site nodule (PSN) is a benign proliferation of chorionic-type intermediate trophoblastic cells that forms a tumor-like lesion. Most PSNs are intrauterine, but a few have been reported outside the uterus, including in fallopian tubes. PSN is related to epithelioid trophoblastic tumor (ETT) in that both are composed of chorionic-type intermediate trophoblastic cells, while ETT is hypercellular and contains trophoblastic cells with increased nuclear atypia and a higher Ki-67 proliferation index as compared with PSN. Occasionally, an intermediate stage between a PSN and an ETT is observed, and such a lesion is often recognized as an atypical PSN (aPSN) characterized by trophoblastic cells exhibiting morphologic features in transition from a conventional PSN to an ETT. aPSN has been thought to exhibit benign behavior; however, it has also been reported that up to 15% of aPSN lesions either coexist with, or subsequently develop into, ETT. To the best of our knowledge, there has been no case report of an aPSN in an extrauterine site. Here, we reported a highly unusual case of tubal aPSN, which illustrates several key features associated with PSN and its possible pathogenesis.

A Multicenter Retrospective Study of Epithelioid Trophoblastic Tumors to Identify the Outcomes, Prognostic Factors, and Therapeutic Strategies

Background

There is no consensus for the management of epithelioid trophoblastic tumor (ETT) up to date.

Objective

ETT is the rarest form of gestational trophoblastic neplasia (GTN). Our goal was to assess the outcomes and explore the prognostic factors of patients with ETT through this multicenter retrospective analysis and to devise a risk-adapted approach to clinical management.

Methods

A total of 31 patients were validated as ETT pathologically between January 2004 and June 2021 from three tertiary hospitals. We retrospectively analyzed the characteristics, treatments, outcomes, and prognostic factors.

Results

Eight patients experienced a recurrence, and 6 patients died of ETT, resulting in a mortality rate of 19.4%. Five patients with stage I disease had a fertility-preserving treatment. Among them, one patient had a full-term delivery, whereas a 23-year-old patient who declined a hysterectomy died of a recurrent disease. Eight patients of extrauterine ETT with isolated pulmonary lesion were at a young age at diagnosis (median: 30.5 vs. 41, p = 0.003) and had a smaller tumor size (median: 2.4 vs. 4.8 cm, p = 0.003) compared with other patients who had a metastatic disease, and none of them died. The multivariate analyses showed that the number of metastases ≥3 [hazard ratio (HR), 28.16, p = 0.003] was the only significant predictor associated with adverse overall survival, while the number of metastases ≥3 (HR 9.59, p = 0.005) and chemotherapy alone (HR 16.42, p = 0.001) were associated with adverse recurrence-free survival. Patients in stage I or with number of metastases <3 had a favorable prognosis, whereas the prognosis of patients whose number of metastases ≥3 remains poor.

Conclusions

Chemotherapy alone is insufficient for patients with ETT. Surgical procedures are the mainstay of management for ETT patients. Combined surgery and multi-agent chemotherapy are recommended for patients with metastatic disease and localized disease with persistently positive human chorionic gonadotrophin levels after surgery. The number of metastases at ≥3 is the most critical risk factor for ETT.

Gestational Trophoblastic Disease: Contemporary Diagnostic Approach

Pathologic diagnosis of gestational trophoblastic disease (GTD)-hydatidiform moles and gestational trophoblastic neoplasms-underwent a major shift in the past decade from morphology-based recognition to precise molecular genetic classification of entities, which also allows for prognostic stratification of molar gestations. This article highlights these recent advances and their integration into the routine pathology practice. The traditional gross and histomorphologic features of each entity are also reviewed with special focus on differential diagnoses and their clinical implications.

Key changes to the world health organisation (who) classification of female genital tumours introduced in the 5TH edition (2020)

An updated World Health Organisation (WHO) Classification of Female Genital Tumours was published in Autumn 2020. We discuss the major new additions and changes from the prior 2014 Classification with discussion of the reasons underlying these. A feature of the new Classification is the greater emphasis on key molecular events with integration of morphological and-molecular features. Most of the major changes from the prior Classification pertain to uterine (corpus and cervix) and vulval tumours but changes in all organs are covered.

Fatal massive pulmonary thromboembolism and concomitant pulmonary trophoblastic embolism associated with exaggerated placental site reaction: a case study

Pulmonary embolism is a major cause of maternal morbidity during pregnancy. Beside the frequently encountered thromboembolism, trophoblastic cell embolism has also been reported in a few case reports. This phenomenon may be symptomless in physiological gestational process but is more pronounced in contexts of preeclampsia or gestational trophoblastic disease. It was exceptionally reported to be associated with death. Here, we report the case of a 15-year-old girl, who experienced dyspnea followed by cardiac arrests and disseminated intravascular coagulation. Echocardiography showed a massive proximal pulmonary embolism. Abdominal sonography revealed that she was 11 weeks pregnant. Autopsy confirmed the presence of multiple clot emboli in the proximal pulmonary arteries. Additionally, the histopathological examination showed a massive syncytiotrophoblastic embolism in the lung microcirculation. Microscopic examination of the uterus revealed an exaggerated placental site reaction. In conclusion, this exhaustive post-mortem study describes a previously unreported association between exaggerated placental site reaction and pulmonary trophoblastic embolism, with fatal issue. Forensic pathologists should be aware that a large sampling of the lungs and uterus and examination of both placenta and fetus are needed to achieve this diagnosis. This case study emphasizes the need for further work elucidating pathways of trophoblast deportation.

Double trouble: Extrauterine epithelioid trophoblastic tumor with uterine choriocarcinoma - An autopsy report

Gestational trophoblastic tumors (GTTs) include choriocarcinoma, epithelioid trophoblastic tumor, and placental site trophoblastic tumor. The occurrence of mixed GTT is rare. We report such a case in a 24-year-old woman who presented with menorrhagia since 2 months and obstetric history of two abortions, one of which was a molar pregnancy. She was undergoing evaluation for carcinoma cervix and treatment for pulmonary tuberculosis from another hospital when she was admitted at our institute for further workup and treatment. However, she succumbed and an autopsy was performed. Histologic evaluation after the autopsy revealed uterine choriocarcinoma with metastatic epithelioid trophoblastic tumor (ETT) in the lung and spleen.

Pathology of gestational trophoblastic disease (GTD)

Gestational trophoblastic disease (GTD) is subclassified into hydatidiform mole (HM), gestational trophoblastic tumours (GTT) and non-neoplastic trophoblastic lesions. HM, partial and complete, originate from villous trophoblast and are considered as preneoplastic conditions. The risk for the development of persistent GTD, mostly as invasive HM, ranges from 0.5% to 20%, which depends on the type of molar pregnancy. The risk of development of trophoblastic tumour after PHM is <0.5% and 2%-3% after CHM. GTT represent a spectrum of neoplasms that originates from the intermediate, largely extravillous, trophoblast and these include choriocarcinoma (CC), placental site trophoblastic tumour (PSTT), epithelioid trophoblastic tumour (ETT) and mixed trophoblastic tumour. Among tumour like conditions, exaggerated placental site reaction (EPSR) and placental site nodule (PSN) (s)/plaque (s) are included. The morphological appearances of HM can be mimicked by abnormal (non-molar) villous lesions, and similarly, GTT can be mimicked both by non-malignant tumour-like conditions and non-gestational tumours with trophoblastic differentiation, which add to the diagnostic dilemma of these rare conditions. GTT have a favourable prognosis and better response to specific chemotherapeutic regimens when compared with non-gestational malignant genital tract neoplasms. The correct diagnosis and classification of these rare conditions are therefore important. This article focusses on the morphological appearances, immunocytochemistry as an aid in the diagnosis and the changes in current WHO classification of GTDs (WHO 2020).

Gestational trophoblastic neoplasia: Novelties and challenges

Gestational trophoblastic diseases are a group of pregnancy-related disorders, originated from trophoblast cells. They include benign and aggressive tumors, such as the invasive mole, the choriocarcinoma, the placental site trophoblastic tumor (PSTT), and the epithelioid trophoblastic tumor (ETT). These malignancies are characterized as gestational trophoblastic neoplasm (GTN), rarer, although more dangerous. The diagnosis of GTN is made in most cases by monitoring serum chorionic gonadotropin (hCG) with histological confirmation. The use of specific tissue biomarkers has been increasingly employed as a differential diagnosis, leading to more accurate results and different therapy protocols and prognosis for each GTN. The treatment is based on the International Federation of Gynecology and Obstetrics anatomical staging system and the World Health Organization prognostic score system. If an accurate diagnosis is made and the guidelines followed, the cure for choriocarcinoma and invasive mole cases can reach 98%, whereas PSTT and ETT still present mild success rates. The improved knowledge about GTN and its peculiarities allows physicians to efficiently achieve the differential diagnosis and choose the best available therapy protocol, thus increasing the overall survival of affected women. Nevertheless, obtaining epidemiological data and improving knowledge through basic and translational research are essential to answer open questions on GTN physiopathology, their causes, and cellular behavior.

A Rare Case of Atypical Placental Site Nodule With an Emerging Intermediate Trophoblastic Tumor

Placental site nodule (PSN) is a benign lesion composed of chorionic-type intermediate trophoblastic cells and is typically an incidental finding in uterine or endocervical curettage specimens. Epithelioid trophoblastic tumor (ETT) and placental site trophoblastic tumor (PSTT) are intermediate trophoblastic neoplasms of chorionic and implantation site types, respectively. ETT is speculated to be the neoplastic counterpart of PSN. The term atypical placental site nodule (APSN) has been proposed for PSN-type lesions displaying one or more concerning features, including larger size/more abundant lesional tissue, more extensive plaque-like growth, increased cellularity with more cohesive nests and cords of cells, a greater extent/distribution of necrosis, increased atypia, mitotic activity, and/or a Ki-67 proliferation index greater than usually encountered in the typical PSN. It has been proposed that APSN is an intermediary lesion between PSN and intermediate trophoblastic tumors, more commonly ETT but also PSTT. We report a case of a 39-yr-old woman who developed abnormal uterine bleeding 44 mo after her last recognized pregnancy. An endometrial curettage specimen demonstrated an APSN with some features concerning for an intermediate trophoblastic tumor. A hysterectomy specimen demonstrated residual APSN with foci consistent with emerging PSTT and ETT. This case illustrates the earliest form of PSTT and ETT arising in association with an APSN and supports interpretation of APSN as an intermediary lesion between typical PSN and intermediate trophoblastic tumors.

Clinical presentation and diagnosis of Gestational Trophoblastic Disease

Gestational trophoblastic disease (GTD) is a heterogeneous group of pregnancy-related disorders characterized by abnormal proliferation of trophoblastic tissue. It encompasses the premalignant partial and complete hydatidiform mole but also the malignant invasive mole, choriocarcinoma, placental-site trophoblastic tumor, and epithelioid trophoblastic tumor. The clinical presentation changed to earlier detection after the introduction of first trimester ultrasounds. Patients are often asymptomatic, but vaginal bleeding continues to be the most common presenting symptom. Other symptoms can develop in the case of metastatic disease. Ultrasound, serum human chorionic gonadotrophin, and sometimes additional imaging such as CT, MRI, or PET can confirm the diagnosis and stage of disease. Familiarity with the pathogenesis, classification, imaging features, and treatment of GTD facilitates diagnosis and appropriate management.

Placental Site Plaque of the Uterine Cervix Misinterpreted as Low-Grade Squamous Intraepithelial Lesion in Liquid-Based Cervicovaginal Cytology: Usefulness of Inhibin-α Immunocytochemistry

Cytological features of placental site plaques in liquid-based cervicovaginal preparations have been seldom documented in the literature. We present a rare case of endocervical placental site plaque misinterpreted as a low-grade squamous intraepithelial lesion in a liquid-based cytological preparation. A 32-year-old woman with polycystic ovarian syndrome gave birth 7 months previously. After delivery, she was diagnosed with cervical low-grade squamous intraepithelial lesion during routine cytological examination. Cytologically, many atypical cells showed large hyperchromatic nuclei with irregular membranes. The perinuclear cytoplasmic clearing closely resembled koilocytosis. Histologically, the endocervix showed typical histological features of a placental site plaque. Immunohistochemically, the trophoblasts were positive for p63, CD10, and inhibin-α but negative for p16. Based on genotyping, both the cytological and biopsied specimens tested negative for human papillomavirus. We re-examined the liquid-based preparation cytology slides thoroughly and concluded that the atypical cells initially misinterpreted as low-grade squamous intraepithelial lesion were actually trophoblasts. Immunocytochemical staining revealed uniform cytoplasmic inhibin-α expression in the trophoblasts. In summary, we demonstrated that endocervical placental site plaques can mimic low-grade squamous intraepithelial lesions in liquid-based cytological preparations. Immunocytochemical staining results and negative results on human papillomavirus genotyping further support that atypical cells resembling koilocytes are trophoblasts obtained from the placental site plaque.

Epithelioid trophoblastic tumor coexisting with choriocarcinoma around an abdominal wall cesarean scar: a case report and review of the literature

Background

Mixed gestational trophoblastic neoplasms are extremely rare and comprise a group of fetal trophoblastic tumors including choriocarcinomas, epithelioid trophoblastic tumors, and placental site trophoblastic tumors. We present a case of a patient with extrauterine mixed gestational trophoblastic neoplasm adjacent to the abdominal wall cesarean scar. On the basis of a literature review, this type of case has never been reported before due to the unique lesion location and low incidence.

Case presentation

Our patient was a 39-year-old Chinese woman who had a history of two cesarean sections and one miscarriage. She had a recurrent anterior abdominal wall mass around her cesarean scar, and the mass was initially suspected of being choriocarcinoma of unknown origin. The patient had concomitant negative or mildly increased serum β-human chorionic gonadotropin at follow-up and no abnormal vaginal bleeding or abdominal pain. However, she underwent local excision twice and had two courses of chemotherapy with an etoposide and cisplatin regimen. She finally opted for exploratory laparotomy with abdominal wall lesion removal, subtotal hysterectomy, bilateral salpingectomy, and left ovarian cyst resection, which showed the abdominal wall lesion, whose components were revealed by microscopy and immunohistochemical staining to be approximately 90% epithelioid trophoblastic tumors and 10% choriocarcinomas from a solely extrauterine mixed gestational trophoblastic neoplasm around an abdominal wall cesarean scar.

Conclusions

It is worth noting whether epithelioid trophoblastic tumor exists in the setting of persistent positive low-level β-human chorionic gonadotropin. More studies are required to provide mechanistic insights into these mixed gestational trophoblastic neoplasms.

A Review on the Pathogenesis and Clinical Management of Placental Site Trophoblastic Tumors

Placental site trophoblastic tumor (PSTT) is a rare type of gestational trophoblastic disease originating from the intermediate trophoblast. Compared with hydatidiform mole, invasive hydatidiform mole and choriocarcinoma, the diagnosis of PSTT is more complicated and lacks specific and sensitive tumor markers. Most PSTT patients demonstrate malignant potential, and the primary treatment of PSTT is hysterectomy. However, metastasis occasionally occurs and even causes death in a small number of PSTT patients. Most PSTT patients are young women hence fertility preservation is an important consideration. The major obstacle for PSTT patient prognosis is chemotherapy resistance. However, the current understanding of the pathogenesis of PSTT and clinical treatment remains elusive. In this review, we summarized the research progress of PSTT in recent years from three aspects: mechanism, clinical presentation, and treatment and prognosis. Well-conducted multi-center studies with sufficient sample sizes are of great importance to better examine the pathological progress and evaluate the prognosis of PSTT patients, so as to develop prevention and early detection programs, as well as novel treatment strategies, and finally improve prognosis for PSTT patients.

Diagnosis and Management of Mixed Gestational Trophoblastic Neoplasia: A Study of 16 Cases and a Review of the Literature

Objective: Mixed gestational trophoblastic neoplasia (GTN) is a rare occurrence that refers to the coexistence of choriocarcinoma and/or placental site trophoblastic tumor and/or epithelioid trophoblastic tumor. The diagnosis and management of mixed GTN are challenging. We investigated the clinicopathological characteristics, diagnoses, treatments, and outcomes of patients with mixed GTN.

Materials and Methods: The medical records and pathological sections of 16 patients with mixed GTN who were treated at Peking Union Medical College Hospital and The Second Xiangya Hospital of Central South University between January 2012 and December 2018 were reviewed.

Results: Pretreatment serum human chorionic gonadotropin (hCG) levels ranged from 180 to 625,024 IU/L, and were >10,000 IU/L in 14 of the 16 patients, none of whom were diagnosed correctly at initial presentation. Two patients were diagnosed with choriocarcinoma coexisting with intermediate trophoblastic tumor (ITT) through dilation and curettage (D&C) before treatment. Another 5 patients were histologically confirmed to have placental site trophoblastic tumor (PSTT) by D&C but final pathological findings showed mixed PSTT and choriocarcinoma at subsequent hysterectomy. Seven post-chemotherapy patients with an initial clinical diagnosis of choriocarcinoma underwent surgery because of chemoresistance and their pathological findings revealed coexisting ITT. The remaining 2 patients were found to have choriocarcinoma coexisting with ITT following cervical biopsy and pulmonary lobectomy. All patients received chemotherapy: 14 underwent surgery combined with chemotherapy and 2 received chemotherapy alone to preserve fertility. Other than 1 patient who died of disease progression, 15 patients (93.8%) achieved complete remission (CR) after treatment, although 5 (33.3%) relapsed. Of these 5 patients with relapse, 3 achieved CR after additional treatment, 1 was receiving an immune checkpoint inhibitor, and 1 was lost to follow-up after refusing further therapy.

Conclusion: Mixed GTN is difficult to diagnose on initial presentation. Overlap of the ITT component should be considered in refractory chemoresistant choriocarcinoma. Coexistence of choriocarcinoma should be suspected in ITT patients with high hCG levels. Surgery combined with chemotherapy is optimal treatment for choriocarcinoma mixed with ITT.

Synchronous Choriocarcinoma and Epithelioid Trophoblastic Tumor Concurring at the Cesarean Scar: A Case Report and Review of the Literature

We present a complicated case of recurrence of gestational trophoblastic neoplasms (GTN), mixed ETT and choriocarcinoma at an abdominal cesarean scar. This tumor consisted of typical morphologic and immunophenotypic features of ETT and choriocarcinoma. The tumor recurred despite the patient undergoing chemotherapy. The patient had this abdominal mass resected three times. The elements of ETT and coexisting choriocarcinoma varied each time. Due to re-recurrence of the tumor, the following decisions had been made: total abdominal hysterectomy, bilateral salpingectomy, right-sided inguinal lymph node biopsy. At the time of this report, recurrence was negative.

Surgery and Platinum/Etoposide-Based Chemotherapy for the Treatment of Epithelioid Trophoblastic Tumor

OBJECTIVE

Epithelioid trophoblastic tumor (ETT) is a rare variant of gestational trophoblastic neoplasia that develops from chorionic-type intermediate trophoblast, simulates carcinoma, presents years after a pregnancy event, is associated with low or normal human chorionic gonadotropin levels, and is relatively resistant to chemotherapy. Our aim was to identify the role of surgery in combination with platinum/etoposide-based chemotherapy in the management of both localized and metastatic ETT.

METHODS

A retrospective review was performed of women with ETT treated at a gestational trophoblastic disease center from 2010 to 2016.

RESULTS

Five patients were identified who had complete records. Mean age was 38.0 years. Three women presented with abnormal uterine bleeding, 2 women presented with respiratory complaints, and 1 woman was asymptomatic. Two women had no identifiable antecedent pregnancy, 2 women had spontaneous abortions, and 1 woman had a normal term delivery before diagnosis. Four (80%) of 5 women had metastatic pulmonary disease. All 5 women underwent hysterectomy, and 3 women had resection of metastatic pulmonary disease. The 4 women with metastatic disease were also treated with chemotherapy. All 5 women are currently without evidence of disease.

CONCLUSIONS

Surgery, including hysterectomy and resection of metastatic disease, is an important component in the treatment of women with ETT. Adjuvant chemotherapy with a platinum/etoposide-containing regimen should be used in women with metastatic disease. All 5 women with ETT in this series were cured using this approach, including the 4 who had metastatic disease.

Primary intrauterine dysgerminoma in a pregnant woman: A rare case report

Primary extraovarian dysgerminoma is very rare. Nearly all reported uterine germ cell tumors are nondysgerminoma. Herein, we reported a primary intrauterine dysgerminoma. A 21-year-old pregnant woman G2 L1 with a gestational age of 33 weeks referred to an obstetric ward with a chief complaint of labor pain and membrane rupture. Ultrasonography showed a large hypoechoic lobulated area adjacent to the lower part of her uterus. She underwent an operation and a huge mass was detected in her uterus, which was extended to her pelvic floor. Histopathological and immunohistochemical examinations were consistent with dysgerminoma.

Extrauterine epithelioid trophoblastic tumors presenting as lung mass: A case report and literature review

RATIONALE

Extrauterine epithelioid trophoblastic tumors (ETT) is a rare variant of gestational trophoblastic neoplasms. Here we aim to learn more clinical and pathological characteristics of ETT patient with an isolated pulmonary mass without uterine lesions, through a rare case of extra-uterine ETT and 7 cases published in English periodicals literature.

PATIENT CONCERNS

A 31-year-old Chinese woman, presented with low-level elevation of serum human chorionic gonadotropin (HCG) for more than 2 years without abnormal symptoms. Dilation and curettage (D&C) was performed and histopathology revealed a secretory phase of endometrium. Chest computed tomography (CT) scan showed a 0.8 cm nodular lesion in the upper left lobe. Then a thoracotomy with left upper lobe segmentectomy was performed.

DIAGNOSIS

After pathological and immunohistochemistry diagnosis, the case was confirmed as ETT (III).

INTERVENTIONS

According to FIGO guideline, the patient took 3 cycles of multivalent chemotherapy consisting of cisplatin and etoposide, alternating with etoposid, methotrexate dactinomycin (EP-EMA).

OUTCOMES

The patient had no obvious signs of recurrence after 13 months of follow-up.

LESSONS

When a fertile age woman persistently shows abnormal low-level escalation of HCG, ETT should be taken into consideration, especially lung X-ray or CT showing lesions without apparent abnormality of the uterus.

A promising therapeutic strategy for metastatic gestational trophoblastic disease: Engineered anticancer gene-expressing stem cells to selectively target choriocarcinoma

Gestational trophoblastic disease (GTD) is an unusual disease occurring in pregnancy that originates from abnormal trophoblastic cells and comprises a group of diseases with different properties of invasion, metastasis and recurrence. The GTD group includes hydatidiform moles and gestational trophoblastic neoplasms (GTNs), with GTNs being divided into invasive moles, choriocarcinoma, placental site trophoblastic tumors and epithelioid trophoblastic tumors. The present review focuses on current effective treatments for GTD, including conventional and novel promising direct enzyme prodrug therapies (DEPTs). Conventional therapies, such as chemotherapy and hysterectomy, are currently used in a clinical setting; however, the use of diverse DEPTs, including antibody-DEPT and gene-DEPT is also being attempted to cure GTNs. In addition, gene delivery tools using genetically engineered neural stem cells (NSCs) are presently being examined for the treatment of GTNs. The tumor-tropism of NSCs by chemoattractant factors is a unique characteristic of these cells and can serve as a vehicle to deliver anticancer agents. Previous studies have demonstrated that injection with NSC-expressing suicide genes into xenograft animal models has a significant inhibitory effect on tumor growth. Stem cells can be genetically engineered to express anticancer genes, which migrate to the metastatic sites and selectively target cancer cells, and are considered to effectively target metastatic GTNs. However, the safety issue of stem cell therapy, such as tumorigenesis, remains a challenge. Novel therapies comprising a combination of conventional and novel promising treatments are anticipated to be definitive treatments for metastasized and/or recurrent patients with GTNs.

P53 expression in various types of hydropic placentas (through ploidy analysis as a complementary tool in diagnosis of samples)

BACKGROUND

Placentas characterized by hydropic swelling of chorionic villi occur in a spectrum of pathological conditions including hydropic abortion (HA), partial hydatidiform mole (PHM) and complete hydatidiform mole (CHM). The purpose of this study was to investigate whether the expression of p53 tumour suppressor protein could differentiate these various types of hydropic placentas.

METHODS

p53 immunohistochemical staining was performed in 19 molar (8 PHM and 11 CHM) and 10 non-molar (HA) formalin-fixed, paraffin-embedded tissue samples. Ploidy analysis using flow cytometry was performed as a complementary tool in diagnosis of samples.

RESULTS

DNA histograms obtained from all samples had confirmed diploidy in HAs and CHMs and triploidy in PHMs. p53 immunoreactivity was assessed in villous cytotrophoblasts, syncytiotrophoblasts and stromal cells. The p53 positive reaction was predominantly observed in the nuclei of cytotrophoblastic cells and rarely in stromal cells, no reaction was seen in syncytiotrophoblasts. The mean percentage of p53 positive cells were 6.10±3.75 for HA, 25.87±13.4 for PHM and 39.83±18.76 for CHM. There was a significant difference in P53 immunoreactivity of cytotrophoblastic cells between CHM and HA (P<0.001), and between PHM and HA (P=0.004). There was no significant difference in immunohistochemical reactivity between CHM and PHM (P=0.068).

CONCLUSION

This study confirms that p53 immunostaining may be helpful in distinguishing complete and partial hydatidiform mole from hydropic abortion, but not complete hydatidiform mole from partial hydatidiform mole.

Gestational Trophoblastic Tumors: A Timely Review of Diagnostic Pathology

CONTEXT.—

Gestational trophoblastic tumors include 3 distinct entities: gestational choriocarcinoma, placental site trophoblastic tumor, and epithelioid trophoblastic tumor. Accurate diagnosis is important for clinical management of the patient.

OBJECTIVE.—

To review clinical features and pathologic diagnosis of gestational trophoblastic tumors.

DATA SOURCES.—

Literature and personal experience are the sources for this study.

CONCLUSIONS.—

Trophoblastic tumors are rare encounters in modern medicine, as a result of clinical practice of molar surveillance programs and early chemotherapeutic intervention for persistent gestational trophoblastic neoplasia. Diagnostic recognition of these tumors requires a high index of suspicion, awareness of their histologic characteristics, and appropriate application of immunohistochemical and molecular biomarkers. Recent attention has been given to a few precursor lesions of gestational trophoblastic tumors, including early/in situ choriocarcinoma and atypical placental site nodule.

A Case Series of Five Patients With Pure or Mixed Gestational Epithelioid Trophoblastic Tumors and a Literature Review on Mixed Tumors

OBJECTIVES

To review the clinicopathologic features of five patients with epithelioid trophoblastic tumor (ETT).

METHODS

Characteristics of patients diagnosed with ETT in 2000 to 2012 were reviewed.

RESULTS

Among 190 patients with gestational trophoblastic neoplasia (GTN), two had pure ETT and three had mixed ETT and choriocarcinoma. The median age was 32.5 years. All the patients had localized disease in the uterus. One patient with pure ETT had a recurrence in the ureter 6 years after the initial treatment. Another patient with pure ETT had two full-term deliveries after fertility-sparing surgery. The three patients with mixed tumors had chemotherapy for GTN before their diseases were completely treated by hysterectomy. At a median follow-up of 102 months, all patients survived.

CONCLUSIONS

ETT is indolent. Recurrence can happen, but the risk factors are not clear. When patients with GTN fail to respond to chemotherapy, the possibility of mixed GTN should be considered.

A typical postcesarean epithelioid trophoblastic lesion with placenta increta: Case report and literature review

We report an extremely rare case of unusual atypical epithelioid trophoblastic lesion from placenta increta. A 25-year-old Chinese woman with a history of 1 cesarean delivery was admitted to the hospital at 37 weeks' gestation. Magnetic resonance imaging (MRI) showed the feature of placenta increta. An elective primary cesarean section was scheduled and a healthy baby was born. The patient was suggestive of placenta increta and implantation site was resected. Histology indicated a lesion consisting of epithelioid trophoblastic cells with an intermediate pattern between a classical placental site nodule and an epithelioid trophoblastic tumor. This may be linked to her previous cesarean delivery, which supports the relationship between atypical epithelioid trophoblastic lesion formation and surgical interventions. Her serum human chorionic gonadotropin (hCG) was 352.4 IU/L after delivery and gradually decreased to normal level.

Metastatic epithelioid trophoblastic tumor of the lung: A case report

RATIONALE

Epithelioid trophoblastic tumor (ETT) is a very rare form of gestational trophoblastic disease (GTD) which arises from neoplastic proliferation of intermediate trophoblasts. Metastatic ETT of the lung is extremely rare in postmenopausal women.

PATIENT CONCERNS

Here we describe a 50-year-old woman with a metastatic ETT of the lung showing increasing tracer uptake at PET/CT.

DIAGNOSIS

Hematoxylin-eosin staining showed a tumor composed of nests of epithelioid cells with necrotic debris and peritumoral hyaline-like material. Immunohistochemical staining of the tumor cells was positive for human chorionic gonadotropin (HCG) and cytokeratin 18.

INTERVENTIONS

The patient underwent thoracoscopic lower left lobectomy combined with mediastinal lymphadenectomy. At surgery, a solid mass (size 3.0 × 3.0 cm) was found in the left lower lung.

OUTCOMES

The patient was discharged on the tenth day postsurgery, following an uneventful recovery. Three months postsurgery, the patient was asymptomatic and is currently being managed with close follow-up.

LESSONS

Metastatic ETT of lung is a very rare disease. Complete surgical resection and chemotherapy may be the critical therapeutic option.

Successful Treatment of Placental Site Trophoblastic Tumor in Twin Pregnancy without Hysterectomy

To the best of the authors’ knowledge, no case of placental site trophoblastic tumor (PSTT) pertinent to twin pregnancy has yet been published. There are only few case reports concerning patients with PSTT who were successfully treated by fertility-sparing methods. A 29-year-old nulliparous woman was admitted to hospital in the 36th week of a twin pregnancy due to symptoms of preterm labor. She underwent a cesarean section, during which a 4-cm uterine mass was found and resected. Histopathology revealed PSTT. Eighteen weeks after the delivery an ultrasound scan displayed another intrauterine mass, 2 cm in size. In the material resected in hysteroscopy there was necrotic decidual tissue. Another 30 months of observation revealed no abnormalities. Even though PSTT is rarely diagnosed, it may cause significant diagnostic and therapeutic problems.

Atypical Placental Site Nodule Arising in a Postcesarean Section Scar: Case Report and Review of the Literature

The distinction between benign and malignant trophoblastic lesions often presents a diagnostic challenge, even in entities with defined morphologic and immunohistochemical criteria. Lesions arising from chorionic-type intermediate trophoblast, namely placental site nodule (PSN) and epithelioid trophoblastic tumor (ETT), can be distinguished by existing criteria. However, a putative intermediate lesion termed "atypical placental site nodule" (APSN) has been described in the literature but is not well-classified. We present a case of APSN, along with a brief literature review, and we propose more definitive morphologic and immunohistochemical criteria for this entity, in order to facilitate easier diagnosis and gather more information regarding outcomes.

Fertility Sparing Strategies in Patients Affected by Placental Site Trophoblastic Tumor

OPINION STATEMENT

Placental site trophoblastic tumor (PSTT) is the least common and the most ambiguous gestational trophoblastic tumor. Presentation of PSTT may occur in the course of gestation or from 1 week to 14 years after a normal or an abnormal pregnancy (mole, ectopic pregnancy, abortion). The indicators of aggressive behavior for this tumor are not well established. Due to the rarity of this disease that usually affects women of childbearing potential, we aimed to review the current literature, to identify risk factors and the best conservative therapeutic choices among the cases described. We performed a systematic literature search of articles in English language, published from 1996 to 2017 and indexed in PubMed and Scopus. Based on selective inclusion/exclusion criteria, we considered eight papers eligible for the review. Five were case reports and three were retrospective studies. We extracted and organized data into three different categories depending on the main treatment used. A total of 12 cases were treated with laparotomy; in 5 cases, the treatment was not curative. Therefore, a total abdominal hysterectomy was needed. Five cases were treated successfully with a minimally invasive approach, 2 with uterine evacuation, 2 with hysteroscopic resection, and 1 with a combined hysteroscopic/laparoscopic resection. Only 1 case treated with exclusive chemotherapy proved curative for the patient. Preservation of fertility in PSTT patients of childbearing age should be considered and as showed by the abovementioned studies, is a possible and safe therapeutic choice. Laparotomy for local uterine resection with the modified Strassman approach could be offered in patients at clinical stage 1 that are very motivated to retain fertility, extensively informing the patient of the risks and benefits related to this choice.

Epithelioid trophoblastic tumor of the uterus: A case report with radiologic-pathologic correlation

Herein, we report a rare case of an epithelioid trophoblastic tumor of the uterus with radiologic-pathologic correlation in a 56-year-old postmenopausal woman. On T2-weighted magnetic resonance (MR) imaging, the tumor appeared as a hypointense irregular mass compared with the surrounding myometrium of the uterine corpus and encircled the cavity of the lower uterine segment. On dynamic contrast-enhanced MR images, the tumor appeared as a hypovascular mass and an inhomogeneously hyperintense mass in the delayed phase. In addition, non-contrast computed tomography images showed some spotty areas of very high density within the tumor. These radiologic findings were well correlated with the histological features, such as abundant hyalinization and calcification within the tumor. Accurate interpretation of MR and computed tomography findings was helpful to differentiate epithelioid trophoblastic tumor from other gestational trophoblastic diseases and uterine carcinomas.

Placental site trophoblastic tumors and epithelioid trophoblastic tumors: Biology, natural history, and treatment modalities

Placental site (PSTT) and epithelioid trophoblastic tumor (ETT) are rare types of gestational trophoblastic neoplasia (GTN) that arise from intermediate trophoblast. Given that this cell of origin is different from other forms of GTN, it is not surprising that the clinical presentation, tumor marker profile, and treatment paradigm for PSTT and ETT are quite different as well. The mainstay for therapy for stage I PSTT and ETT is hysterectomy with adjuvant chemotherapy reserved for those presenting greater than four years from the antecedent pregnancy. Surgery is also important for metastatic disease. There is no standardized chemotherapy regimen for advanced stage disease but often consists of a platinum-containing combination therapy, usually EMA-EP or TE/TP. Despite its rarity, PSTT and ETT account for a disproportionate percentage of mortality from GTN likely resulting from their relative chemotherapy resistance. Novel therapeutic modalities therefore are needed to improve the outcomes of women with advanced stage or resistant PSTT and ETT.

Ovarian Epithelioid Trophoblastic Tumor in a Cynomolgus Monkey

Epithelioid trophoblastic tumor (ETT) is an unusual type of trophoblastic tumor, with features resembling carcinoma. In this study, we describe a 4-year-old cynomolgus monkey ( Macaca fascicularis) showing, at necropsy, a lobulated mass replacing the left ovary and several nodular lesions within the lungs. Histologically, the mass in the ovary and lung metastases were characterized by nests of epithelioid cells, with intermingled, occasional, multinucleate tumor cells consistent with syncytiotrophoblasts and moderate amount of eosinophilic, hyaline-like material. Immunohistochemically, the tumor cells were diffusely positive for cytokeratins (AE1/AE3) and inhibin-α, but only focal immunoreactivity was observed for human chorionic gonadotropin, whereas placental alkaline phosphatase was always negative. On the basis of morphology and immunohistochemical reactivity, tumor cells were identified as intermediate trophoblast.

Disseminated disease including intra-cardiac metastasis from intermediate trophoblastic tumor of unspecified subtype, presenting in pregnancy

•Cardiac metastasis is a rare manifestation of trophoblastic malignancy•Previous cases have exclusively been reported in choriocarcinoma histology•Our case describes cardiac metastasis, as part of disseminated disease, from an intermediate trophoblastic tumor.•Our patient initially responded systemically to chemotherapy for a brief duration•However, she died from CNS failure 4½ months after diagnosis.