Systemic therapy for primary and extragonadal germ cell tumors: prognosis and nuances of treatment

Recent Advancements in Research on DNA Methylation and Testicular Germ Cell Tumors: Unveiling the Intricate Relationship

Testicular germ cell tumors (TGCTs) are the most common type of testicular cancer, with a particularly high incidence in the 15-45-year age category. Although highly treatable, resistance to therapy sometimes occurs, with devastating consequences for the patients. Additionally, the young age at diagnosis and the treatment itself pose a great threat to patients' fertility. Despite extensive research concerning genetic and environmental risk factors, little is known about TGCT etiology. However, epigenetics has recently come into the spotlight as a major factor in TGCT initiation, progression, and even resistance to treatment. As such, recent studies have been focusing on epigenetic mechanisms, which have revealed their potential in the development of novel, non-invasive biomarkers. As the most studied epigenetic mechanism, DNA methylation was the first revelation in this particular field, and it continues to be a main target of investigations as research into its association with TGCT has contributed to a better understanding of this type of cancer and constantly reveals novel aspects that can be exploited through clinical applications. In addition to biomarker development, DNA methylation holds potential for developing novel treatments based on DNA methyltransferase inhibitors (DNMTis) and may even be of interest for fertility management in cancer survivors. This manuscript is structured as a literature review, which comprehensively explores the pivotal role of DNA methylation in the pathogenesis, progression, and treatment resistance of TGCTs.

The potential role of miRNAs in the pathogenesis of testicular germ cell tumors - A Focus on signaling pathways interplay

Testicular germ cell tumors (TGCTs) are the most common testicular neoplasms in adolescents and young males. Understanding the genetic basis of TGCTs represents a growing need to cope with the increased incidence of these neoplasms. Although the cure rates have been comparatively increased, investigation of mechanisms underlying the incidence, progression, metastasis, recurrence, and therapy resistance is still necessary. Early diagnosis and non-compulsory clinical therapeutic agents without long-term side effects are now required to reduce the cancer burden, especially in the younger age groups. MicroRNAs (miRNAs) control an extensive range of cellular functions and exhibit a pivotal action in the development and spreading of TGCTs. Because of their dysregulation and disruption in function, miRNAs have been linked to the malignant pathophysiology of TGCTs by influencing many cellular functions involved in the disease. These biological processes include increased invasive and proliferative perspective, cell cycle dysregulation, apoptosis disruption, stimulation of angiogenesis, epithelial-mesenchymal transition (EMT) and metastasis, and resistance to certain treatments. Herein, we present an up-to-date review of the biogenesis of miRNAs, miRNA regulatory mechanisms, clinical challenges, and therapeutic interventions of TGCTs, and role of nanoparticles in the treatment of TGCTs.

A Challenging Case of Heart Displacement by a Large Mediastinal Germ Cell Tumor

Mediastinal germ cell tumors (GCTs) are rare and aggressive cancers originating from the germ cells in the mediastinum. Early detection and treatment are vital due to their high potential for metastasis and recurrence. We present a case of a 28-year-old man who exhibited a cough and shortness of breath. Laboratory tests revealed elevated tumor markers, alpha-fetoprotein, and beta-human chorionic gonadotropin. Imaging studies displayed a large mediastinal mass, causing the right displacement of the mediastinum and cardiac tamponade. The biopsy confirmed a non-seminomatous GCT, specifically a yolk sac tumor. The patient experienced pericardial effusion and cardiac tamponade after receiving two cycles of etoposide and cisplatin chemotherapy. To relieve the tamponade, an emergency pericardiocentesis was performed malignant GCTs necessitate prompt diagnosis and treatment and utilizing multimodal therapy such as chemotherapy to achieve tumor control. Due to the high risk of metastasis, vigilant surveillance for recurrence is essential, emphasizing the need for specific criteria for accurate early detection.

Fluorescent in-situ hybridization test performed on cell blocks is useful for establishing germ cell origin of metastatic tumors with unusual clinical presentation

The majority of germ cell tumors (GCTs) are characterized by iso-chromosome 12p (i12p) abnormality. The aim of this study is to review the cytomorphologic features and analyze the utility of i12p fluorescent in-situ hybridization (FISH) test in diagnosing metastatic GCTs primarily evaluated by cytologic techniques in patients without prior history of GCTs. The laboratory information system was queried over a period of 10 years to search for cases where i12p FISH test was requested on cytology material. FISH test was performed using TelVysion 12p telomeric probe and CEP 12 centromere probe on cell-blocks. A ratio of 12ptel/CEP12 signal of 1.4 or greater was considered as positive. Patient demographics, clinical presentation, cytopathologic findings, and follow-up surgical resection data were reviewed and correlated. A total of three cases were identified, all men (age range 31-60 years). Cytologic diagnoses were favor metastatic embryonal carcinoma (Case 1, retroperitoneal fluid FNA), metastatic yolk sac tumor/YST (Case 2, lung mass FNA) and adenocarcinoma, likely representing a somatic-type malignancy (SM) arising from a preexisting GCT (Case 3, retroperitoneal mass FNA). This limited study demonstrated high sensitivity for detecting i12p abnormality by FISH test performed on cell blocks. The cytomorphology of extra-gonadal GCTs varies according to the histologic subtype. Sarcomatoid morphology of YST, SM or mixed GCTs further complicates cytology evaluation. FISH test for detection of i12p performed on cell-blocks is extremely useful in establishing germ cell origin of these metastatic GTCs with unusual cytomorphology and guides management in patients without prior history of GCTs.

Epigenetics and Testicular Cancer: Bridging the Gap Between Fundamental Biology and Patient Care

Testicular cancer is the most common solid tumor affecting young males. Most testicular cancers are testicular germ cell tumors (TGCTs), which are divided into seminomas (SGCTs) and non-seminomatous testicular germ cell tumors (NSGCTs). During their development, primordial germ cells (PGCs) undergo epigenetic modifications and any disturbances in their pattern might lead to cancer development. The present study provides a comprehensive review of the epigenetic mechanisms–DNA methylation, histone post-translational modifications, bivalent marks, non-coding RNA–associated with TGCT susceptibility, initiation, progression and response to chemotherapy. Another important purpose of this review is to highlight the recent investigations regarding the identification and development of epigenetic biomarkers as powerful tools for the diagnostic, prognostic and especially for epigenetic-based therapy.

Clinical Experience of Male Primary Choriocarcinoma at the Samsung Medical Center

PURPOSE

The objective of this study was to describe and analyze the clinicopathological features of primary choriocarcinoma (PCC) observed in male patients treated at the Samsung Medical Center between 1996 and 2020.

MATERIALS AND METHODS

We reviewed the clinical records of 14 male patients with PCC retrospectively to assess their demographic, histological, and clinical characteristics at the time of diagnosis as well as identify the treatment outcomes.

RESULTS

The median age of the patients was 33 years. The primary tumor site was the testicles in seven cases (50%), the mediastinum in six cases (43%), and the brain in one case (7%). The most common metastatic site was the lungs (79%), followed by the brain (43%). All patients with PCC received cytotoxic chemotherapy. Twelve patients had records of their response to cytotoxic chemotherapy; of these 12 patients, eight (8/12, 67%) achieved an objective response, and four (4/12, 33%) achieved stable disease response as the best response during chemotherapy.

CONCLUSION

It is known that most male PCC patients eventually develop resistance to cytotoxic chemotherapy and die. Factors such as poor response to chemotherapy, high disease burden, brain metastasis, and hemoptysis at the time of diagnosis are associated with shorter survival time in male PCC patients. Programmed death-1/programmed death-ligand 1 blockade therapy can be a salvage treatment for chemotherapy-resistant male PCC patients.

LAPTM5 Plays a Key Role in the Diagnosis and Prognosis of Testicular Germ Cell Tumors

Objective

Testicular germ cell tumors (TGCT) are a serious malignant tumor with low early diagnosis rates and high mortality.

Methods

To investigate novel biomarkers to predict the diagnosis and prognosis of this cancer, bioinformatics analysis was used as an accurate, efficient, and economical method.

Results

Our study detected 39 upregulated and 589 downregulated differentially expressed genes (DEGs) using the GEO and TCGA databases. To identify the function of DEGs, GO functional analysis, three pathway analysis (KEGG, REACTOME, and PANTHER), and protein-protein interaction network were performed using the KOBAS website, as well as the String database. After a series of analyses in GEPIA and TIMER, including differential expression, we found one candidate gene related to the prognosis and diagnosis of TGCT. LAPTM5 was also associated with CD8+ T cell and PDCD1 expression, which suggests that it may affect immune infiltration.

Conclusions

LAPTM5 was identified as a hub gene, which could be used as a potential biomarker for TGCT diagnosis and prognosis.