Gestational trophoblastic neoplasia of intermediate trophoblasts: Epithelioid trophoblastic tumor and placental site trophoblastic tumor, a study of morphologic, immunohistochemical, and next generation sequencing

Objective

Gestational trophoblastic tumors are very rare neoplasms. We determined the distinctive morphological, immunohistochemical, and clinical features of placental site trophoblastic tumors (PSTT) and epithelioid trophoblastic tumors (ETT) in our cohort.

Materials and Methods

Nine cases of PSTT and four cases of ETT were retrieved from the archives. Histomorphologic, immunohistochemical, and clinical features were noted. A molecular study was performed on one PSTT and one ETT case using next-generation sequencing.

Results

While the nodular pattern, geographic necrosis, and extracellular eosinophilic globules were peculiar to ETTs, vessel wall affinity, marked pleomorphism, intranuclear pseudoinclusion, spindle tumor cell, and vacuolar degeneration were more specific for PSTTs in our series. An immunohistochemical panel of p63, hPL, and CD146 were helpful for the exact typing of the tumor. p63 positivity supports the ETT and diffuse staining of hPL and CD146 supports the PSTT diagnosis. Three of the patients with metastatic disease (lung and brain metastasis) except one have a high mitotic count (12 and 8) and a long interval between (8 and 10 years) antecedent pregnancy and diagnosis. While KIT and TP53 mutations were observed only in PSTT, amino acid changes in KDR, APC, and SMAD4 genes were detected both in the ETT and PSTT cases.

Conclusion

In the prediction of metastasis, the long intervals between antecedent pregnancy and diagnosis, deep myometrial invasion, mitotic count, and Ki67 proliferation index were involved rather than other histomorphological parameters, but none of the parameters is an absolute predictor of the metastasis.

Placental site trophoblastic tumor (PSTT): a case report and review of the literature

Placental site trophoblastic tumor (PSTT), also known as atypical choriocarcinoma, syncytioma, chorioepitheliosis or trophoblastic pseudotumor, is a rare gestational trophoblastic disease (0.25-5% of all trophoblastic tumors) and it is composed by neoplastic proliferation of intermediate trophoblasts at placental implantation site. It consists of aggregates or sheets of large, polyhedral to round, predominantly mononucleated cells with a characteristic vascular and myometrial invasion. Main differential diagnoses are gestational choriocarcinoma (GC) and epitelioid trophoblastic tumor (ETT). We present a case of PSTT in a 25-year-old woman. Neoplastic cells showed moderate/high nuclear pleomorphism, abundant amphophilic, eosinophilic and clear cytoplasm, numerous mitotic figures (10 mitoses/10 HPF), and myometrial invasion. Other features are necrosis, vascular invasion with replacement of myometrial vessels by tumor cells and hemorrhage. The patient showed typical low serum β-hCG levels and high serum humane placental lactogen (hPL) levels.

Diagnosis and management of gestational trophoblastic disease: 2021 update

Gestational trophoblastic disease (GTD) arises from abnormal placenta and is composed of a spectrum of premalignant to malignant disorders. Changes in epidemiology of GTD have been noted in various countries. In addition to histology, molecular genetic studies can help in the diagnostic pathway. Earlier detection of molar pregnancy by ultrasound has resulted in changes in clinical presentation and decreased morbidity from uterine evacuation. Follow-up with human chorionic gonadotropin (hCG) is essential for early diagnosis of gestational trophoblastic neoplasia (GTN). The duration of hCG monitoring varies depending on histological type and regression rate. Low-risk GTN (FIGO Stages I-III: score <7) is treated with single-agent chemotherapy but may require additional agents; although scores 5-6 are associated with more drug resistance, overall survival approaches 100%. High-risk GTN (FIGO Stages II-III: score ≥7 and Stage IV) is treated with multiagent chemotherapy, with or without adjuvant surgery for excision of resistant foci of disease or radiotherapy for brain metastases, achieving a survival rate of approximately 90%. Gentle induction chemotherapy helps reduce early deaths in patients with extensive tumor burden, but late mortality still occurs from recurrent treatment-resistant tumors.

Guideline No. 408: Management of Gestational Trophoblastic Diseases

OBJECTIVE

This guideline reviews the clinical evaluation and management of gestational trophoblastic diseases, including surgical and medical management of benign, premalignant, and malignant entities. The objective of this guideline is to assist health care providers in promptly diagnosing gestational trophoblastic diseases, to standardize treatment and follow-up, and to ensure early specialized care of patients with malignant or metastatic disease.

INTENDED USERS

General gynaecologists, obstetricians, family physicians, midwives, emergency department physicians, anaesthesiologists, radiologists, pathologists, registered nurses, nurse practitioners, residents, gynaecologic oncologists, medical oncologists, radiation oncologists, surgeons, general practitioners in oncology, oncology nurses, pharmacists, physician assistants, and other health care providers who treat patients with gestational trophoblastic diseases. This guideline is also intended to provide information for interested parties who provide follow-up care for these patients following treatment.

TARGET POPULATION

Women of reproductive age with gestational trophoblastic diseases.

OPTIONS

Women diagnosed with a gestational trophoblastic disease should be referred to a gynaecologist for initial evaluation and consideration for primary surgery (uterine evacuation or hysterectomy) and follow-up. Women diagnosed with gestational trophoblastic neoplasia should be referred to a gynaecologic oncologist for staging, risk scoring, and consideration for primary surgery or systemic therapy (single- or multi-agent chemotherapy) with the potential need for additional therapies. All cases of gestational trophoblastic neoplasia should be discussed at a multidisciplinary cancer case conference and registered in a centralized (regional and/or national) database.

EVIDENCE

Relevant studies from 2002 onwards were searched in Embase, MEDLINE, the Cochrane Central Register of Controlled Trials, and Cochrane Systematic Reviews using the following terms, either alone or in combination: trophoblastic neoplasms, choriocarcinoma, trophoblastic tumor, placental site, gestational trophoblastic disease, hydatidiform mole, drug therapy, surgical therapy, radiotherapy, cure, complications, recurrence, survival, prognosis, pregnancy outcome, disease outcome, treatment outcome, and remission. The initial search was performed in April 2017 and updated in May 2019. Relevant evidence was selected for inclusion in the following order: meta-analyses, systematic reviews, guidelines, randomized controlled trials, prospective cohort studies, observational studies, non-systematic reviews, case series, and reports. Additional significant articles were identified through cross-referencing the identified reviews. The total number of studies identified was 673, with 79 studies cited in this review.

VALIDATION METHODS

The content and recommendations were drafted and agreed upon by the authors. The Executive and Board of Directors of the Society of Gynecologic Oncology of Canada reviewed the content and submitted comments for consideration, and the Board of Directors for the Society of Obstetricians and Gynaecologists of Canada approved the final draft for publication. The quality of evidence was rated using the criteria described in the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) methodology framework. See the online appendix tables for key to grading and interpretation of recommendations.

BENEFITS

These guidelines will assist physicians in promptly diagnosing gestational trophoblastic diseases and urgently referring patients diagnosed with gestational trophoblastic neoplasia to gynaecologic oncology for specialized management. Treating gestational trophoblastic neoplasia in specialized centres with the use of centralized databases allows for capturing and comparing data on treatment outcomes of patients with these rare tumours and for optimizing patient care.

SUMMARY STATEMENTS (GRADE RATINGS IN PARENTHESES)

RECOMMENDATIONS (GRADE RATINGS IN PARENTHESES).

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.

Differential expression of cyclin E, p63, and Ki-67 in gestational trophoblastic disease and its role in diagnosis and management: A prospective case-control study

Background

Gestational trophoblastic disease (GTD) constitutes a spectrum of tumors and tumor-like conditions, characterized by proliferation of pregnancy-associated trophoblastic tissue of progressive malignant potential. It is very difficult to differentiate these complex groups of lesions basing on histomorphology alone. Immunohistochemistry (IHC) with cyclin E, P63, and Ki-67 has a definite role in the identification of different trophoblasts and entities of GTD and also in the determination of biological behavior.

Aims

The aim of this study is to find the differential expression of cyclin E, p63, and Ki-67 in normal placenta, hydropic abortus (HA), and various entities of GTD.

Design and Settings

A prospective case-control study conducted in a government medical college.

Methods

Total 96 cases, divided into Group A (48 histologically confirmed cases of GTD) and Group B (controls comprising 8 HA and 40 normal placentas of different trimesters), were studied. The histological samples were subjected to IHC using cyclin E, Ki-67, and p63.

Statistical Analysis

Results were analyzed using SPSS statistical method.

Results

Among the three immunomarkers used, Cyclin E and Ki-67 show statistically significant difference (P < 0.05) when compared between GTD and control groups, but it was insignificant for p63 (P = 0.369). Strong staining intensity of cyclin E and Ki-67 is seen in complete moles, choriocarcinoma, and placental site trophoblastic tumor.

Conclusion

This study was done to evaluate the role of cell cycle regulatory proteins such as cyclin E and p63 and proliferation marker Ki-67 in the detection of various trophoblasts and differential diagnosis of the lesions associated with them.

CARE-Placental site trophoblastic tumor presenting with thrombotic microangiopathy: A case report

RATIONALE

Placental site trophoblastic tumor (PSTT) is a rare form of gestational trophoblastic neoplasm (GTN).

PATIENT CONCERNS

A 28-year-old Chinese female with initial presentation of thrombotic microangiopathy (TMA) with symptoms of edema of the lower extremities and eyelid, thrombocytopenia and anemia.

DIAGNOSES

The primary diagnosis was chronic glomerulonephritis according to the related laboratory tests and clinical symptoms.

INTERVENTIONS

A total abdominal hysterectomy with a bilateral salpingectomy was performed.

OUTCOMES

The PSTT patient was cured, which contributed to the symptom relief of TMA.

LESSONS

This case report aims to elucidate the relationship between TMA and PSTT, so as to achieve timely diagnosis and treatment and reduce misdiagnosis.

Disappearance of a thrombotic microangiopathy-like glomerular lesion in a patient with a placental site trophoblastic tumor after hysterectomy

A 32-year-old woman presented with amenorrhea after a normal childbirth and subsequently developed nephrotic syndrome. Renal biopsy showed a thrombotic microangiopathy (TMA)-like glomerular lesion with deposits of immunoglobulins, complements, and fibrinogen. Increased serum levels of the beta subunit of human chorionic gonadotropin, abnormal uterine findings from imaging studies, and endometrial biopsy findings suggested gestational trophoblastic disease. She was diagnosed with a placental site trophoblastic tumor (PSTT) after hysterectomy and, following treatment, her proteinuria disappeared. Follow-up renal biopsy showed the disappearance of the TMA-like lesion. To our knowledge, this is the first case report of the pathological remission of renal disease associated with PSTT.

A case of placental site trophoblastic tumor complicating nephrotic syndrome in which hysteroscopic biopsy did not yield a definitive diagnosis

Placental site trophoblastic tumor (PSTT) is the rarest subtype of gestational trophoblastic neoplasm. We present a case of PSTT complicating nephrotic syndrome. A 32-year-old woman experienced irregular menstrual bleeding and lower extremity edema 18 months after delivery. She was diagnosed with nephrotic syndrome and exaggerated placental site based on the hysteroscopic biopsy results. During follow-up, transvaginal color Doppler ultrasound showed an enlarged uterus filled with a hypervascular mass. Positron emission tomography–computed tomography showed diffuse accumulation in the entire uterus. The patient was diagnosed with PSTT only after total hysterectomy. Postoperatively, serum β-human chorionic gonadotropin decreased to within the normal range and her nephrotic syndrome resolved. She has remained without evidence of recurrence for 15 months. It is difficult to diagnose PSTT definitively. Most patients with PSTT are of reproductive age, therefore, to maintain fecundity, therapy development is expected.

Coexisting epithelioid trophoblastic tumor and placental site trophoblastic tumor of the uterus following a term pregnancy: report of a case and review of literature

Gestational trophoblastic neoplasms are a group of fetal trophoblastic tumors including choriocarcinomas, epithelioid trophoblastic tumors (ETTs), and placental site trophoblastic tumors (PSTTs). Mixed gestational trophoblastic neoplasms are extremely rare. The existence of mixed gestational trophoblastic neoplasms that were composed of choriocarcinoma and/or PSTT and/or ETT was also reported. Herein, we present a case of uterine mixed gestational trophoblastic neoplasm which is ETT admixed with PSTT, and reviewed 9 cases of mixed gestational trophoblastic neoplasms reported in English literature available. The most common combination was a choriocarcinoma admixed with an ETT and/or PSTT. Mixed gestational trophoblastic neoplasms present in women of reproductive age and rare in postmenopausal, Abnormal vaginal bleeding is the most common presenting symptom, serum β-HCG levels are elevated, mostly below 2500 mIU/ml, the tumor was limited to uterus in 7 cases, the rest of 3 with pulmonary metastases at the time of diagnosis. Mixed gestational trophoblastic neoplasms have more similar clinical features with intermediate trophoblastic tumors (ITTs). Total hysterectomy with lymph node dissection is recommended treatment for mixed gestational trophoblastic neoplasms, and chemotherapy should be used in patients with metastatic disease and with nonmetastatic disease who have adverse prognostic factors.