Short tandem repeat analysis to identify the causative pregnancy of high-risk gestational trophoblastic neoplasia: Molar versus nonmolar pregnancy and its relation to the outcome

Malignancy following solid organ transplantation: Current techniques for determination of donor versus recipient origin

Among the post-transplantation complications that patients may encounter, the transmission of a donor-derived malignant neoplasm is uncommon but potentially life threatening. The determination of donor versus recipient origin is essential particularly in the setting of multiple transplant recipients from the donor. Advances in molecular biology now allow accurate discrimination utilizing routine tissue samples in a timely and cost-effective manner. The techniques are routinely performed in hospital molecular biology laboratories and are also available in commercial labs. The current methodologies are discussed and future possibilities are presented for clinicians caring for solid organ recipients.

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.

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.

Short Tandem Repeat DNA Profiling Using Perylene-Oligonucleotide Fluorescence Assay

We report an amplification-free genotyping method to determine the number of human short tandem repeats (STRs). DNA-based STR profiling is a robust method for genetic identification purposes such as forensics and biobanking and for identifying specific molecular subtypes of cancer. STR detection requires polymerase amplification, which introduces errors that obscure the correct genotype. We developed a new method that requires no polymerase. First, we synthesized perylene-nucleoside reagents and incorporated them into oligonucleotide probes that recognize five common human STRs. Using these probes and a bead-based hybridization approach, accurate STR detection was achieved in only 1.5 h, including DNA preparation steps, with up to a 1000-fold target DNA enrichment. This method was comparable to PCR-based assays. Using standard fluorometry, the limit of detection was 2.00 ± 0.07 pM for a given target. We used this assay to accurately identify STRs from 50 human subjects, achieving >98% consensus with sequencing data for STR genotyping.

Case report: Using DNA short tandem repeats to confirm nongestational origin of pulmonary choriocarcinoma

Gestational trophoblastic neoplasias (GTN) are malignant neoplasms that occur in pregnant or recently pregnant women. Choriocarcinoma (CCA) is a highly aggressive and rare GTN, and cases outside the female genital tract are commonly seen as secondary manifestations of gynecologic disease. In this paper, we describe the case of a 40 years-old female patient with a primary pulmonary CCA who was surgically treated and for whom the confirmation of the primary origin of the tumor was possible using a DNA short tandem repeat genotyping. Distinction between gestational and non-gestational trophoblastic neoplasia is crucial as they require different therapeutic approach and have different prognoses.

Epidemiologic study on gestational trophoblastic diseases in Japan

Objective

This study aims to estimate the population-based incidence of gestational trophoblastic diseases (GTDs) and to identify the characteristics of gestational trophoblastic neoplasia (GTN) in Japan.

Methods

The annual number of GTD and live births from 1974 to 2018 were used to estimate the incidence of GTD. The data of 1,574 GTN cases from 1999 to 2018 were analyzed to identify the characteristics of low-risk GTN, high-risk GTN, placental site trophoblastic tumor (PSTT), and epithelioid trophoblastic tumor (ETT).

Results

The incidence of hydatidiform mole was 2.02 per 1,000 live births on average which decreased from 1974 to 2008 and increased from 2009 to 2018. The incidence of low-risk GTN, high-risk GTN, PSTT, and ETT was 15.3, 3.5, 0.3, and 0.07 per 100,000 live births, respectively. The estimated incidence of post-molar GTN was 9.8% of molar patients. High-risk GTN was diagnosed more pathologically, had more various kinds of antecedent pregnancies, and had longer intervals after the antecedent pregnancy compared to low-risk GTN. Furthermore, 8.2% of high-risk GTN occurred after the subsequent non-molar pregnancy of hydatidiform mole. The cumulative percentage of developing high-risk GTN after hydatidiform mole reached 89.3% at the 60th month.

Conclusion

The incidence of hydatidiform mole, low-risk GTN, high-risk GTN was 2.02 per 1,000 live births, 15.3 per 100,000 live births, and 3.5 per 100,000 live births, respectively. High-risk GTN was diagnosed more pathologically and later after the antecedent pregnancy than low-risk GTN. Following molar patients for five years is needed to improve the mortality of malignant GTN.

The incidence of hydatidiform mole and gestational trophoblastic neoplasia (GTN) in Japan was estimated. The incidence of post-molar GTN was stable at approximately 10%. Of high-risk GTN, 8.2% occurred after the subsequent non-molar pregnancy of hydatidiform mole. Following molar patients for 5 year is necessary for early diagnosis of high-risk GTN.

Short tandem repeat polymorphism analysis for primary peritoneal choriocarcinoma: A case report and literature review

The peritoneum is an extremely rare site for primary choriocarcinoma development. Primary peritoneal choriocarcinoma could be either gestational or nongestational, whereas it is straightforward to ascribe uterine or tubal choriocarcinoma to the gestational origin. Herein, we report a case of primary peritoneal choriocarcinoma that is genetically diagnosed as a gestational subtype originating from an occult complete hydatidiform mole. A 46-year-old female patient with two-time induced abortion histories underwent emergency laparotomy under clinical suspicion of ruptured tubal pregnancy. Laparotomy revealed a hemorrhagic tumor in the left mesosalpinx with apparently intact left ovary and fallopian tube. The excised tumor was pathologically diagnosed as choriocarcinoma. Multiplex short tandem repeat polymorphism analysis revealed an androgenetic/homozygous genotype tumor, identifying its origin as a complete hydatidiform mole. Our literature review of nine primary peritoneal choriocarcinoma cases, including ours, highlighted the importance of tumor genotyping in differentiating between gestational and non-gestational subtypes and identifying the causative pregnancy.