Role of immune checkpoint inhibitors combined with chemotherapy in recurrent drug-resistant gestational trophoblastic neoplasia: Four case reports and literature review.

BACKGROUND: Multiple studies have confirmed that programmed cell death 1 (PD-1) and programmed cell death ligand 1 (PD-L1) is widely expressed in gestational trophoblastic neoplasia (GTN) tissues. Therefore, immune checkpoint inhibitors may be an option for the treatment of recurrent and drug-resistant GTN. CASE: Four patients with recurrent or drug-resistant GTN who were treated with PD-1/PD-L1 checkpoint inhibitor agents combined with chemotherapy were reported. The mean age of recurrence was 45.8 years (35-56 years), including three cases of choriocarcinoma (CC) and one case of invasive mole (IM). International Federation of Gynecology and Obstetrics (FIGO) prognosis score: ≤6 (low risk) in one case, 7-12 (high risk) in one case, ≥13 (very high risk) in two cases. There were two cases of lung metastasis and one case of vulvar and inguinal lymph node metastasis. One of the four patients underwent total hysterectomy and one patient underwent resection of lung metastases. All the four patients received comprehensive treatment of immunotherapy combined with chemotherapy after relapse, among which one patient achieved complete response (CR), two patients achieved partial response (PR), and one patient developed progressive disease (PD). Three patients who achieved PR or CR were maintained by single agent immunotherapy after combination therapy, and there was no disease recurrence during follow-up. One patient with PD also achieved CR after using salvage chemotherapy after recurrence, and there was no disease recurrence during follow-up. During the treatment, four patients had different degrees of immune-related adverse reactions, all of which were grade I-II, and no severe adverse reactions were found. CONCLUSION: Immune checkpoint inhibitors combined with chemotherapy has an impressive therapeutic effect on recurrent or drug-resistant GTN with mild adverse reactions, which can be used as a treatment option for such patients. However, due to the lack of large sample data support, the specific time and treatment course of its use, long-term use of adverse reactions and whether it affects fertility function remain to be solved.

Postpartum choriocarcinoma - a rare cause of delayed postpartum hemorrhage: Four case reports and literature review.

BACKGROUND: Delayed postpartum hemorrhage is rare, with an incidence of 0.5% to 2.0% in all pregnancies. The most important causes are placental remnants, infections, and placental bed subinvolution. Postpartum choriocarcinoma, a highly malignant complication of pregnancy, is a rare condition that can be easily misdiagnosed as other common causes, such as gestational remnants, and delays the diagnosis. METHODS: Four patients visited our clinic complaining of delayed postpartum hemorrhage, combined with respiratory and neurological symptoms in 2 cases. Two cases were confirmed by histopathological examination and in addition, medical history, elevated human chorionic gonadotropin (hCG) level, and imaging findings help confirm the diagnosis of delayed postpartum hemorrhage caused by postpartum choriocarcinoma in other cases. Individualized combination chemotherapies were prescribed. In the light of massive cerebral metastasis in case 2, intrathecal methotrexate injection combined with whole-brain radiotherapy was prescribed. RESULTS: Due to the absence of routine monitoring of ß-hCG following full-term delivery, there was widespread metastasis at the time of diagnosis. Three patients got complete remission and there is no sign of recurrence. One patient had relapse and widespread metastasis and died at home 6 months after the last chemotherapy. CONCLUSION: It is important to be aware of the possibility of choriocarcinoma in patients with delayed postpartum hemorrhage. Clinicians should improve the recognition of choriocarcinoma following full-term delivery, emphasize the monitoring of ß-hCG, comprehensively analyze the general condition of patients, and conduct standardized and individualized chemotherapy protocols.

Chemotherapy is not needed when complete evacuation of gestational choriocarcinoma leads to hCG normalization.

BACKGROUND: The standard treatment for gestational choriocarcinoma is chemotherapy. OBJECTIVE: To describe the risk of recurrence with expectant management of gestational choriocarcinoma that has reached a normal human chorionic gonadotropin level after tumor removal without adjuvant chemotherapy. METHODS: A retrospective multicenter international cohort study was conducted from 1981 to 2017 involving 11 gestational trophoblastic disease reference centers with patient's follow-up extended until 2023. Clinical and biological data of included patients were extracted from each center's database. The inclusion criteria were i) histological diagnosis of gestational choriocarcinoma in any kind of placental tissue retrieved, ii) spontaneous normalization of human chorionic gonadotropin level following choriocarcinoma retrieval, iii) patient did not receive any oncological treatment for the choriocarcinoma, iv) and at least 6 months of follow-up after the first human chorionic gonadotropin level normalization. RESULTS: Among 80 patients with retrieved gestational choriocarcinoma and whose human chorionic gonadotropin level normalized without any other oncological therapy, none had a recurrence of choriocarcinoma after a median follow-up of 50 months. The median interval between choriocarcinoma excision and human chorionic gonadotropin level normalization was 48 days. The International Federation of Gynecology and Obstetrics/World Health Organization risk score was ≤6 in 93.7% of the cases. CONCLUSIONS: This multicenter international study reports that selected patients with gestational choriocarcinoma managed in gestational trophoblastic disease reference centers did not experience any relapse when the initial tumor evacuation is followed by human chorionic gonadotropin level normalization without any additional treatment. Expectant management may be a safe approach for highly selected patients.

Intracardiac metastasis of gestational choriocarcinoma: a case report and literature review.

INTRODUCTION: Gestational trophoblastic neoplasia (GTN) with intracardiac metastasis is rare, and here we reported a patient with intracardiac metastasis of high-risk and refractory gestational choriocarcinoma and reviewed relevant literatures. CASE PRESENTATION: A 37-year-old woman presented with vaginal bleeding and high level of ß-human chorionic gonadotropin (ß-hCG) at 199,060 (mIU/mL). It was clinically diagnosed with gestational choriocarcinoma. The patient initially received eight cycles of chemotherapy but unsatisfactory response was observed, and the level of ß-hCG still ranged between 5000 and 10,000. Then there was found intracardiac masses in the right atrium (2.6*1.7 cm), anterior chordae tendineae of the tricuspid valve (1.4*0.7 cm) and the right ventricle (4.1*2.9 cm) by ultrasonic cardiogram (UCG). PET/CT highly suspected the intracardiac metastasis of choriocarcinoma (SUVmax = 9.3) and no disease was found in the lung and pelvis. The patient undertook complete intracardiac masses resection. The pathology confirmed the intracardiac metastasis of disease. After a week of operation, the UCG found a 5.4*4.2 cm mass in the right atrium again. Considering the poor prognosis, the patient received palliative care and eventually died of disease progression. CONCLUSION: Intracardiac metastasis of GTN is an aggressive sign of disease. Patients can benefit from chemotherapy and surgery. Future investigation of PD-1 immunotherapy combines with chemotherapy are expected to improve the prognosis in this group of patients.

Effect of lung metastasis on the treatment and prognosis of patients with gestational trophoblastic neoplasia: A systematic review and meta-analysis.

INTRODUCTION: Gestational trophoblastic neoplasia (GTN) is a highly invasive tumor, mainly spreading to the lungs. However, lung metastasis in GTN is usually not considered as an adverse prognostic factor. Therefore, the aim of this study was to summarize the results of previous studies and evaluate the effects of lung metastasis on the treatment and prognosis of GTN. MATERIAL AND METHODS: The study was prospectively registered in PROSPERO (CRD42023372371). Electronic databases including PubMed, Embase, the Cochrane Library, Chinese National Knowledge Infrastructure, Wanfang, and China Biomedical Literature Database were used for a systematical search of relevant studies published up to November 21, 2022. The observational studies reporting the clinical outcomes of GTN patients with and without lung metastasis were selected. The incidences of resistance, relapse, and mortality of GTN patients were extracted and successively grouped based on the presence of lung metastasis. The pooled relative risks (RRs) and 95% confidence interval (95% CI) of the eligible studies were calculated. The qualities of included studies were assessed with the Newcastle-Ottawa Scale and the certainty of evidence was graded based on the GRADE. The meta-analysis was performed using Stata 12.0 and GradePro software. RESULTS: Five publications with 3629 GTN patients were included. The meta-analysis revealed that the GTN with lung metastasis was strongly correlated with first-line chemoresistance (pooled RR = 1.40, 95% CI: 1.22 to 1.61, p < 0.001), recurrence (pooled RR = 3.03, 95% CI: 1.21 to 7.62, p = 0.018), and disease-specific death (pooled RR = 22.11, 95% CI: 3.37 to 145.08, p = 0.001). Ethnicity was also an important factor and Caucasian GTN patients with lung metastasis showed a higher risk of recurrence as revealed by the subgroup analysis (pooled RR = 5.10, 95% CI: 2.38 to 10.94, p < 0.001). CONCLUSIONS: GTN patients with lung metastasis exhibited a higher risk of chemoresistance, relapse, and disease-specific death. Patients with lung metastasis among the Caucasian population had a higher risk of recurrence than Asian populations. Therefore, the presence of lung metastases might be considered as a high-risk factor for prognosis of GTN and deserves more attention in the choice of first-line chemotherapy regimens and follow-up.

Ovarian non-gestational placental site trophoblastic tumor with lung metastasis: further evidence for a distinct category of trophoblastic neoplasm.

We previously described a series of cases which characterize a distinct group of primary ovarian placental site trophoblastic tumor (PSTT) and epithelioid trophoblastic tumor (ETT) as a non-gestational set consistent with germ cell type/origin. Here we report a new case of ovarian non-gestational PSTT. The patient was a 13 year-old young female admitted for a spontaneous pneumothorax of the left lung. The pathology of lung wedge excision specimen demonstrated metastatic PSTT and ovarian biopsy showed atypical intermediate trophoblastic proliferation which was found to be PSTT in the subsequent salpingo-oophorectomy specimen. In the ovary, the tumor was composed of singly dispersed or small clusters of predominantly mononuclear cells and rare multinucleated cells extensively infiltrating the ovarian parenchyma, tubal mucosa, and paraovarian/paratubal soft tissue. A minor component of mature cystic teratoma (less than 5% of total tumor volume) was present. Immunohistochemically, the neoplastic cells of main tumor were diffusely immunoreactive for hPL, Gata3 and AE1/AE3, and had only rare hCG-positive or p63-positive cells. The morphology and immunohistochemical results support a PSTT. Molecular genotyping revealed an identical genotype pattern between the normal lung tissue and the metastatic PSTT, indicating its non-gestational nature of germ cell type/origin. This case represents the first case of such tumor with distant (lung) metastasis. This case also provides further evidence to support our recommendation that primary ovarian non-gestational intermediate trophoblastic tumors of germ cell type/origin, including PSTT and ETT, should be formally recognized in classification systems.

Atypical Placental Site Nodules within the Diverticulum of the Uterine Incision, a Rare Gestational Trophoblastic Disease Misdiagnosed as Intrauterine Residue: A Case Report.

Atypical placental site nodule (APSN) is a rare benign gestational trophoblastic disease (GTD). It is a tumor-like transformation that has a certain probability of developing into a placental site trophoblastic tumor (PSTT) or epithelioid trophoblastic tumor (ETT). Because of its atypical clinical presentation, it is difficult to diagnose and susceptible to misdiagnosis highly, thus delaying the patient's condition. We report a scarce case of atypical nodules at the placental site of the uterine incision diverticulum in a 35-year-old female, who was irregular vaginal bleeding after a cesarean Sect. 2 years. She was diagnosed by several local hospitals with intrauterine residue and was given a variety of Traditional Chinese Medicine (TCM) orally, but the symptoms of irregular vaginal bleeding have not been alleviated. After being transferred to several hospitals, she went to Hubei Maternal and Child Health Hospital for treatment. Under the condition of excluding the second pregnancy, she underwent hysteroscopic resection of lesions and laparoscopic repair of uterine incision diverticulum. The pathological diagnosis after the operation suggested that the focus at the uterine incision was an atypical placental nodule that invaded the myometrium of the uterus. The operation completely removed the focus, and then the patient was followed up every 3 months in the first postoperative year, then every 6 months up to 3 years, and then annually thereafter up to 5 years, and then maybe every 2 years thereafter. The patient's condition was quickly controlled, and the prognosis was good.

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.

Progress of immunotherapies in gestational trophoblastic neoplasms.

BACKGROUND: Different from other malignant gynecologic tumors, gestational trophoblastic neoplasms (GTNs) exhibit an exceptionally high cure rate primarily through chemotherapeutic interventions. However, there exists a small subset of refractory GTNs that do not respond to conventional chemotherapies. In such cases, the emergence of immunotherapies has demonstrated significant benefits in managing various challenging GTNs. PURPOSE: This article aims to provide a comprehensive and systematic review of the immune microenvironment and immunotherapeutic approaches for GTNs. The purpose is to identify potential biomarkers that could enhance disease management and summarize the available immunotherapies for ease of reference. METHODS: We reviewed the relevant literatures toward immunotherapies of GTNs from PubMed. CONCLUSION: Current immunotherapeutic strategies for GTNs mainly revolve around immune checkpoint inhibitors (ICIs) targeting programmed death receptor 1 (PD-1) and programmed cell death ligand 1 (PD-L1). Prominent examples include avelumab, pembrolizumab, and camrelizumab. However, existing researches into the underlying mechanisms are still limited.

Immunotherapy in the treatment of chemoresistant gestational trophoblastic neoplasia - systematic review with a presentation of the first 4 Brazilian cases.

OBJECTIVE: To evaluate the efficacy of immunotherapy for GTN treatment after methotrexate-resistance or in cases of multiresistant disease, through a systematic review, as well as to present the first 4 Brazilian cases of immunotherapy for GTN treatment. METHODS: Three independent researchers searched five electronic databases (EMBASE, LILACS, Medline, CENTRAL and Web of Science), for relevant articles up to February/2023 (PROSPERO CRD42023401453). The quality assessment was performed using the Newcastle Ottawa scale for case series and case reports. The primary outcome of this study was the occurrence of complete remission. The presentation of the case reports was approved by the Institutional Review Board. RESULTS: Of the 4 cases presented, the first was a low-risk GTN with methotrexate resistance unsuccessfully treated with avelumab, which achieved remission with sequential multiagent chemotherapy. The remaining 3 cases were high-risk multiagent-resistant GTN that were successfully treated with pembrolizumab, among which there were two subsequent gestations, one of them with normal pregnancy and healthy conceptus. Regarding the systematic review, 12 studies were included, only one of them on avelumab, showing a 46.7% complete remission rate. The remaining 11 studies were on pembrolizumab, showing an 86.7% complete remission rate, regardless of tumor histology. Both immunotherapies showed good tolerability, with two healthy pregnancies being recorded: one after avelumb and another after pembrolizumab. CONCLUSION: Immunotherapy showed effectiveness for GTN treatment and may be especially useful in cases of high-risk disease, where pembrolizumab achieves a high therapeutic response, regardless of the histological type, and despite prior chemoresistance to multiple lines of treatment.

The impact of the distance traveled between residence and gestational trophoblastic neoplasia reference center and clinical outcomes in Brazilian women.

OBJECTIVE: To relate the distance traveled from the patient's residence to the gestational trophoblastic neoplasia (GTN) reference center (RC) and the occurrence of unfavorable clinical outcomes, as well as to estimate the possible association between this distance and the risk of metastatic disease at presentation, the need for multiagent chemotherapy to achieve remission and loss to follow-up before remission. STUDY DESIGN: Retrospective historical cohort study of patients with GTN followed at 8 Brazilian GTN-RC, from January 1st, 2000 - December 31st, 2017. RESULTS: Evaluating 1055 cases of GTN, and using a receiver operating characteristic curve, we found a distance of 56 km (km) from the residence to the GTN-RC (sensitivity = 0.57, specificity = 0.61) best predicted the occurrence of at least one of the following outcomes: occurrence of metastatic disease, need for multiagent chemotherapy to achieve remission, or loss to follow-up during chemotherapy. Multivariate logistic regression adjusted by age, ethnicity, marital status and the reference center location showed that when the distance between residence and GTN-RC was ≥56 km, there was an increase in the occurrence of metastatic disease (relative risk - RR:3.27; 95%CI:2.20-4.85), need for multiagent chemotherapy (RR:1.36; 95%CI:1.05-1.76), loss to follow-up during chemotherapy (RR:4.52; 95CI:1.93-10.63), occurrence of chemoresistance (RR:4.61; 95%CI:3.07-6.93), relapse (RR:10.27; 95%CI:3.08-34.28) and death due to GTN (RR:3.62; 95%CI:1.51-8.67). CONCLUSIONS: The distance between the patient's residence and the GTN-RC is a risk factor for unfavorable outcomes, including death from this disease. It is crucial to guarantee these patients get prompt access to the GTN-RC and receive follow-up support.

Pulmonary resection of residual lesions of pulmonary metastasis from gestational trophoblastic neoplasia.

OBJECTIVE: To evaluate the prognosis and recurrence in patients with residual lesions of pulmonary metastasis from gestational trophoblastic neoplasia after initial treatment, and to explore the clinical significance of pulmonary resection. METHODS: A retrospective analysis was performed on 606 patients with residual lesions from pulmonary metastasis after receiving standardized chemotherapy as initial treatment in Peking Union Medical College Hospital from January 2002 to December 2018. Patients were divided into surgery (51 patients) and non-surgery (555 patients) groups. The prognosis of these patients was compared. Risk factors affecting recurrence were analyzed to explore the effect of pulmonary resection. RESULTS: Among low risk patients, complete remission rate was 100% and recurrence rate was <1% in both groups. Among high risk patients, complete remission and recurrence rates were 93.5% and 10.3% in the surgery group and 94.7% and 14.3% in the non-surgery group, respectively. There was no significant difference in prognostic features between the two groups (all p>0.05). No significant difference was found in recurrence rates based on recurrence risk factors (≥3.2 cm residual lung lesions, prognosis score ≥9.0, and drug resistance) between the two groups (all p>0.05). CONCLUSION: After standardized chemotherapy, pulmonary resection was not necessary for initially treated stage III gestational trophoblastic neoplasia patients whose blood ß human chorionic gonadotropin levels normalized and residual lung lesions remained stable. These patients should be closely monitored during follow-up, regardless of the size of the residual lung lesions or high/low risk score, especially within a year after complete remission.

Clinical Features of Gestational Trophoblastic Disease in Aged Women in South Vietnam.

PURPOSE: This study aimed to determine the occurrence rate of gestational trophoblastic neoplasia (GTN) and its related factors in aged women with hydatidiform mole (HM) in Tu Du Hospital, Vietnam. MATERIALS AND METHODS: This retrospective cohort study included 372 women aged ≥40 years with HM diagnosed through post-abortion histopathological assessment in Tu Du Hospital from January 2016 to March 2019. Survival analysis was used for GTN cumulative rate estimation, log-rank test for group comparison, and Cox regression model for determining GTN-related factors. RESULTS: After a 2-year follow-up, 123 patients were found to have GTN at a rate of 33.06% [95% confidence interval (CI): 28.30-38.10]. GTN occurrence meant that the time was 4.15±2.93 weeks with peaks at week 2 and 3 after curettage abortion. The GTN rate was remarkably higher in the ≥46-year age group than in the 40-to-45-year age group [hazard ratio (HR)=1.63; 95%CI: 1.09-2.44], as was the vaginal bleeding group compared to the non-bleeding group (HR=1.85; 95%CI: 1.16-2.96). Preventive hysterectomy and preventive chemotherapy plus hysterectomy in the intervention group reduced the GTN risk compared to the no intervention group at HRs of 0.16 (95%CI: 0.09-0.30) and 0.09 (95%CI: 0.04-0.21), respectively. Chemoprophylaxis failed to decrease the GTN risk when comparing the two groups. CONCLUSION: Post-molar pregnancy GTN rate in aged patients was 33.06%, much higher than that of the general population. Preventive hysterectomy or chemoprophylaxis plus hysterectomy are effective treatment methods to support GTN risk reduction.

Application of Current Pathologic Criteria for Atypical Placental Site Nodule Suggests That Refined Criteria Are Needed.

Atypical placental site nodules (APSNs) are histologically intermediate between placental site nodules (PSNs) and epithelioid trophoblastic tumors (ETTs). Little data exists to characterize these lesions and the risk of transformation from PSN to ETT. Recent World Health Organization (WHO) criteria for distinction of APSN are vague and not objectively defined. We identified cases signed out as PSN (n=33) and APSN (n=11) and aimed to characterize, statistically compare, and assess the risk of transformation in PSNs using data including size, location, mitotic rate, Ki-67 proliferation index, trophoblastic cells per high-power field, presence of severe cytologic atypia, beta-human chorionic gonadotropin levels, time since last pregnancy, presence of calcification, necrosis, or apoptosis, and follow-up results. All cases were confirmed to be positive for p63, and a Ki-67/AE1/AE3 dual stain was used to evaluate the Ki-67 proliferation index in the trophoblastic cells. In our cohort, slight changes in the interpretation of WHO criteria for PSN and APSN led to marked differences in the proportion of PSNs flagged as "atypical." There was no statistically significant difference in the persistence of APSN versus non-APSN. None of the PSNs transformed to ETT. Current criteria for distinction between PSN and APSN are largely subjective. More objective, clearly defined, and clinically meaningful criteria are needed to distinguish between PSN and APSN, thus aiding in assessing the rare risk of transformation to ETT.

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.

Presentation, medical complications and development of gestational trophoblastic neoplasia of hydatidiform mole after intracytoplasmic sperm injection as compared to hydatidiform mole after spontaneous conception - a retrospective cohort study and literature review.

OBJECTIVE: To describe the natural history of hydatidiform mole (HM) after intracytoplasmic sperm injection (ICSI), emphasizing the clinical and oncological outcomes, as compared to patients who had HM after spontaneous conception (SC). STUDY DESIGN: Retrospective historical cohort study of patients with HM followed at the Rio de Janeiro Federal University, from January 1st 2000-December 31st 2020. RESULTS: Comparing singleton HM after SC to those following ICSI there were differences in terms of maternal age (24 vs 34 years, p < 0.01), gestational age at diagnosis (10 vs 7 weeks, p < 0.01), preevacuation human chorionic gonadotropin levels (200,000 vs 99,000 IU/L, p < 0.01), occurrence of genital bleeding (60.5 vs 26.9%, p < 0.01) and hyperemesis (23 vs 3.9%, p = 0.02) at presentation, and time to remission (12 vs 5 weeks, p < 0.01), respectively. There were no differences observed in the cases of twin mole, regardless of the form of fertilization that gave rise to HM, except molar histology with greater occurrence of partial hydatidiform mole (10.7 vs 40.0%, p = 0.01) following ICSI. Univariate logistic regression for occurrence of postmolar GTN after ICSI identified no predictor variable for this outcome. However, after adjusting for maternal age and complete hydatidiform mole histology, multivariable logistic regression showed the risk of GTN with HM after ICSI had an adjusted odds ratio of 0.22 (95%CI:0.05-0.93, p = 0.04), suggesting a possible protective effect when compared to HM after SC. CONCLUSIONS: Singleton HM after ICSI are diagnosed earlier in gestation, present with fewer medical complications, and may be less likely to develop GTN when compared with HM after SC.