Immunotherapy in Testicular Germ Cell Tumors

Unwrapping the immunological alterations in testicular germ cell tumors: From immune homeostasis to malignancy and emerging immunotherapies

BACKGROUND

Testicular germ cell tumors (TGCTs), derived from primordial germ cells, are rare malignancies with high curative potential. However, the emergence of new evidence indicating that 15% of patients experience tumor progression, leading to death, underscores the need for innovative therapeutics.

OBJECTIVES

This review aimed to explore the immune status in maintaining testicular health and the immune-related aspects of malignancy. Furthermore, it presents an overview of current data on the use of immunotherapy for TGCT patients.

RESULTS AND DISCUSSION

Recent advances in immunology have opened a promising avenue for studying diseases and highlighted its role in treating diseases. While the immunopathological facets of TGCTs are not fully understood, investigations suggest a complex interplay among testis-resident immune cells, testis-specific cells (i.e., Sertoli cells (SCs) and Leydig cells (LCs)), and immune-regulating mediators (e.g., sex hormones) in the normal testicle that foster the testicular immune privilege (TIP). Although TIP plays a crucial role in sperm production, it also makes testis vulnerable to tumor development. In the context of cancer-related inflammation, disruption of TIP leads to an imbalanced immune response, resulting in chronic inflammation that can contribute to testicular tissue dysfunction or loss, potentially aiding in cancer invasion and progression.

CONCLUSION

Comparing the immune profiles of normal and malignant testes is valuable and may provide insights into different aspects of testicular immunity and immune-based treatment approaches. For patients resistant to chemotherapy and with a poor prognosis, immunotherapy has shown promising results. However, its effectiveness in treating resistant TGCTs or preventing tumor recurrence is still uncertain.

Single-cell profiling in ovarian germ cell and sex cord-stromal tumours

BACKGROUND

The tumour microenvironment of rare ovarian germ cell tumours (OGCT) and sex-cord stromal tumours (SCST) remains unexplored. To better understand their immune and stromal landscape, we constructed a blueprint using single-cell RNA sequencing (scRNA-seq).

METHODS

We performed scRNA-seq of 66, 919 cells from twelve fresh tumour samples: seven adult granulosa cell tumour (aGSCT), one juvenile GSCT (jGSCT), one Sertoli-Leydig (SL) tumour, two immature teratoma (IT) and one dysgerminoma (DG). We characterised immune cell subtypes and fibroblasts based on their specific marker genes. Validation included combined positive score (CPS) of 46 OGCTs and 66 SCSTs, and bulk RNA sequencing (n = 32).

RESULTS

Cell clustering and annotation revealed a immune-activated microenvironment in DG, driven by PD-1- exhausted T cells, reflected in high CPS (≥10) and upregulated immune pathways. IT samples displayed no immunoreactive profile, consistent with a negative CPS. aGSCTs exhibited a fibroblast-enriched, immune-desert phenotype, with low T cell infiltration and increased immunosuppressive LYVE1 and CX3CR1+ macrophages, corresponding to negative CPS.

CONCLUSION

We constructed a detailed blueprint of the OGCT and SCSTs microenvironment of, elucidating potential modulators that shape their immune landscape. The immune-suppressive environment in aGSCTs likely limits immunotherapy response, as immunosuppressive macrophages inhibit T cell expansion along with EMT activation and fibroblast predominance.

The role of immunotherapy in targeting tumor microenvironment in genitourinary cancers

Genitourinary (GU) cancers, including renal cell carcinoma, prostate cancer, bladder cancer, and testicular cancer, represent a significant health burden and are among the leading causes of cancer-related mortality worldwide. Despite advancements in traditional treatment modalities such as chemotherapy, radiotherapy, and surgery, the complex interplay within the tumor microenvironment (TME) poses substantial hurdles to achieving durable remission and cure. The TME, characterized by its dynamic and multifaceted nature, comprises various cell types, signaling molecules, and the extracellular matrix, all of which are instrumental in cancer progression, metastasis, and therapy resistance. Recent breakthroughs in immunotherapy (IO) have opened a new era in the management of GU cancers, offering renewed hope by leveraging the body's immune system to combat cancer more selectively and effectively. This approach, distinct from conventional therapies, aims to disrupt cancer's ability to evade immune detection through mechanisms such as checkpoint inhibition, therapeutic vaccines, and adoptive cell transfer therapies. These strategies highlight the shift towards personalized medicine, emphasizing the importance of understanding the intricate dynamics within the TME for the development of targeted treatments. This article provides an in-depth overview of the current landscape of treatment strategies for GU cancers, with a focus on IO targeting the specific cell types of TME. By exploring the roles of various cell types within the TME and their impact on cancer progression, this review aims to underscore the transformative potential of IO strategies in TME targeting, offering more effective and personalized treatment options for patients with GU cancers, thereby improving outcomes and quality of life.

Mechanisms of cisplatin sensitivity and resistance in testicular germ cell tumors and potential therapeutic agents (Review)

Testicular germ cell tumors (TGCTs) are the most common tumors in men aged 20-40 years and are primarily treated with cisplatin-based drugs. Although TGCTs are highly sensitive to DNA damage induced by cisplatin and show a hypersensitive apoptotic response, cisplatin resistance still exists. Emerging evidence shows that cisplatin resistance in TGCTs is mainly related to the inhibition of apoptotic pathways such as MDM2/p53, OCT4/NOXA, PDGFR/PI3K/AKT, inhibition of cell cycle checkpoints, increased methylation or neddylation and DNA repair balance. In this review, recent advances regarding the mechanisms of TGCTs' sensitivity and resistance to cisplatin were summarized and potential therapeutic agents for cisplatin-resistant TGCTs were presented, providing a new therapeutic strategy for drug-resistant TGCTs.

Pembrolizumab and olaparib in a cisplatin-refractory testicular cancer patient with a high TMB: first case report

Germ cell tumors (GCTs) represent about 5% of urological cancers affecting mostly younger males with increasing incidence in the last decades. GCTs are very sensitive to cisplatin-based therapy and are highly curable regardless of metastatic stage, likely based on having inherited unique mechanisms of sensitivity to DNA damage and other stressors to prevent germline mutations. Here, we present the first case of a 60-year Caucasian male with a heavily pretreated, cisplatin-refractory extragonadal non-seminomatous GCT (choriocarcinoma) treated with pembrolizumab and olaparib based on high programmed death-ligand 1 expression (tumor proportion score 50% and a combined positive score 55%) high tumor mutational burden, borderline genomic loss of heterozygosity, and a heterozygous variant of uncertain significance in the DNA repair gene ATM, as confirmed by next-generation sequencing (NGS) analysis. Despite a notable decrease in b-hCG within 4 weeks after starting pembrolizumab and olaparib, b-hCG increased steadily again afterward. In addition, the patient developed an immune-related pneumonitis with a fatal outcome 3 months later. NGS with subsequent targeted treatment possibilities might present a helpful step toward precision medicine in GCT patients who have exhausted all other conventional treatment options, and genetic testing should therefore be offered to patients prior to progression.

Immune Checkpoint Inhibitors in Patients with Testicular Cancer: A Systematic Review

Germ cell tumors (GCTs) are chemosensitive neoplasms with high cure rates; however, a small group of patients present tumors with refractory chemotherapy, with a dismal prognosis and few effective management options. Although immune checkpoint inhibitors (ICIs) are approved for use in chemotherapy refractory GCT, the evidence supporting this indication remains scarce. Original research studies were included on patients with GCTs refractory to chemotherapy treated with ICI up to December 2023. Comprehensive search strategies databases and MeSH keywords were used to locate eligible literature. Study characteristics, participant demographics, and oncological outcomes were recorded. A total of 13 studies (n = 106) were included, five single-patient case reports, one retrospective cohort, six-phase II randomized controlled trials (RCTs), and an abstract from the preliminary results of a phase II RCT. Most of the studies evaluated did not request biomarkers as inclusion criteria. Median overall response rate across studies was 3.4% (range, 0-57) and 0% (range, 0-6) in retrospective cohort and phase II studies. Progressive disease as the best response was present in most patients, with 75% (range, 0-82.9) in the overall population and 82% (range, 75 -83) in the retrospective cohort and phase II trials. Some of the most durable clinical responses documented in this systematic review corresponded to high tumor mutational burden (TMB-H) or high microsatellite instability (MSI-H)/dMMR tumors. Retrospective cohorts and clinical trials evaluating ICIs for the treatment of chemo-refractory GCTs documented limited activity of these drugs as a single intervention in patients not selected by biomarkers, with a tendency to better results described in those with TMB-H or MSI-H/dMMR tumors.

Role of Neoadjuvant Immunotherapy in Genitourinary Malignancies

Genitourinary (GU) malignancies are common and associated with significant morbidity and mortality. In patients with localized GU cancers, surgical resection or definitive radiation remain the mainstays of treatment. Despite definitive treatment, many patients with high-risk localized disease experience recurrence. There is growing interest in using neoadjuvant immunotherapy to improve outcomes. This narrative review summarizes the current evidence for neoadjuvant immunotherapy in patients with localized high-risk GU cancers including renal cell carcinoma, urothelial carcinoma, prostate cancer, penile squamous cell carcinoma, and testicular germ cell tumors. We also discuss ongoing clinical trials and candidate biomarkers to optimize patient selection and improve treatment outcomes.

PARP inhibitors in testicular germ cell tumors: what we know and what we are looking for

Testicular germ cell tumors (TGCTs), the most common malignancies affecting young men, are characterized by high sensitivity to cisplatin-based chemotherapy, which leads to high cure rates even in metastatic disease. However, approximately 30% of patients with metastatic TGCTs relapse after first-line treatment and those who can be defined as platinum-refractory patients face a very dismal prognosis with only limited chemotherapy-based treatment options and an overall survival of few months. Hence, to understand the mechanisms underlying cisplatin resistance is crucial for developing new treatment strategies. This narrative review explores the potential role of PARP inhibitors (PARPis) in overcoming cisplatin resistance in TGCTs, starting from the rationale of their ability to induce DNA damage in cells with homologous recombination repair (HRR). Thus far, PARPis have failed to show meaningful clinical activity in platinum-refractory TGCT patients, either alone or in combination with chemotherapy. However, few responses to PARPis in TGCTs have been detected in patients with BRCA1/2, ATM or CHEK2 mutations, reinforcing the idea that patients should be optimally selected for tailored treatments in the era of personalized medicine. Future preclinical and clinical research is needed to further investigate the molecular mechanisms of cisplatin resistance and to identify novel therapeutic strategies in resistant/refractory TGCTs patients.

Spinal Metastases in Non-Seminomatous Germ Cell Testicular Tumors: Prognosis and Integrated Therapeutic Approaches-A Systematic Review with an Institutional Case Illustration

(1) Background: Testicular cancer, although accounting for only 0.5% to 1% of all solid male cancers, is the most common malignancy in males aged 15 to 35 years. Non-seminomatous germ cell tumors (NSGCT) represent nearly half of all testicular germ cell tumors and are associated with a more aggressive clinical course. Spinal metastases, while rare, pose significant challenges due to their potential to cause spinal cord compression, neurological deficits, and severe pain. This systematic review aims to evaluate prognosis and treatment approaches for spinal metastases in NSGCT, with a focus on multidisciplinary care and treatment outcomes. (2) Methods: A systematic review was conducted following PRISMA guidelines. PubMed, Scopus, and Embase were searched on 18 September 2024, using the Boolean search strategy [(Nonseminomatous germ cell tumor (NSGCT) AND (spinal OR vertebral metastases)]. Case reports, case series, and cohort studies providing detailed patient data were included. Data on patient demographics, tumor histology, metastatic site, treatments, and outcomes were extracted for analysis. (3) Results: A total of 164 cases of NSGCT with spinal metastases were analyzed, with patients aged 23 to 40 years (median: 31.5 years). The lumbar spine was involved in all cases, and spinal cord compression occurred in 59.8% of patients, often causing severe neurological symptoms such as cauda equina syndrome. Chemotherapy, primarily cisplatin-based, was administered in all cases, while surgical interventions, including laminectomy and vertebrectomy, were performed in cases of spinal compression and instability. Complete remission occurred in only 2.4% of patients. Progressive improvement was observed in 56.7% of cases, while 20.1% of patients died. Outcomes varied, highlighting the importance of individualized, multidisciplinary care to manage both systemic and localized disease. (4) Conclusions: Spinal metastases in NSGCT represent a complex clinical scenario, requiring a combination of chemotherapy, surgery, and in some cases, radiotherapy. Chemotherapy remains essential, but surgery is critical for addressing spinal compression and instability. A multidisciplinary approach is vital for optimizing outcomes, as prognosis is variable, with some patients achieving improvement while others face progressive disease or death. Further research is needed to refine the role of radiotherapy and improve long-term treatment strategies for this rare complication.

The Evolving Molecular Landscape and Actionable Alterations in Urologic Cancers

The genetic landscape of urologic cancers has evolved with the identification of actionable mutations that impact diagnosis, prognosis, and therapeutic strategies. This narrative review consolidates existing literature on genetic mutations across key urologic cancers, including bladder, renal, prostate, upper tract urothelial, testicular, and penile. The review highlights mutations in DNA damage repair genes, such as BRCA1/2 and PTEN, as well as pathway alterations like FGFR and PD-L1 overexpression. These mutations influence tumor behavior and therapeutic outcomes, emphasizing the need for precision oncology approaches. Molecular profiling, through tools like next-generation sequencing, has revolutionized patient care by enabling targeted treatment strategies, especially in cancers with distinct molecular subtypes such as luminal or basal bladder cancer and clear cell renal carcinoma. Emerging therapies, including FGFR inhibitors and immune checkpoint blockade, offer new treatment avenues, although resistance mechanisms remain a challenge. We also emphasize the importance of biomarker identification for personalized management, especially in metastatic settings where treatment intensification is often required. Future research is needed to further elucidate our understanding of the genetics affecting urologic cancers, which will help develop novel, individualized therapies to enhance oncologic outcomes.

Dysgerminomas: germ cell tumors exhibit high expression of PD-L1 and associated with high TILs and good prognosis

Ovarian germ cell tumors (OVGCTs) account for 28% of all diagnosed ovarian cancers, and malignant germ cell tumors specifically account for approximately 13% of diagnosed ovarian cancers in Saudi Arabia. Although most germ cell tumor patients have a high survival rate, patients who experience tumor recurrence have a poor prognosis and present with more aggressive and chemoresistant tumors. The use of immunotherapeutic agents such as PD-L1/PD-1 inhibitors for OVGCTs remains very limited because few studies have described the immunological characteristics of these tumors. This study is the first to investigate PD-L1 expression in ovarian germ cell tumors and explore the role of PD-L1 expression in tumor microenvironment cells and genetic alterations. A total of 34 ovarian germ cell tumors were collected from pathology archives. The collected tumor tissues included ten dysgerminomas, five yolk sac tumors, five immature teratomas, and one mature teratoma, and the remaining samples were mixed germ cell tumors. The tumors were analyzed using immunohistochemical analysis to determine PD-L1 expression, immune cell infiltration and cancer stem cell populations and their correlation with clinical outcome. Furthermore, the genetic alterations in different subtypes of germ cell tumors were correlated with PD-L1 expression and clinical outcome. Datasets for testicular germ cells (TGCTs) were retrieved from The Cancer Genome Atlas (TCGA) and analyzed using cBioPortal (cbioportal.org) and Gene Expression Profiling Interactive Analysis (GEPIA). Compared with yolk sac tumors, dysgerminomas highly express PD-L1 and are associated with high levels of tumor infiltrating lymphocytes (TILs) and stem cell markers. In addition, compared with PD-L1-negative yolk sac tissue, dysgerminomas/seminomas with high PD-L1 expression are associated with more genetic alterations and a better prognosis. Our findings will contribute to the knowledge about the potential benefits of ovarian cancer immunotherapy in specific subsets of germ cell tumor patients and the risk factors for resistance mediated by tumor microenvironment cells.

Sustained Response to Anti-PD-1 Therapy in Combination with Nab-Paclitaxel in Metastatic Testicular Germ Cell Tumor Harboring the KRAS-G12V Mutation: A Case Report

INTRODUCTION

Cisplatin-based standardized therapy has been established for metastatic testicular germ cell tumors (TGCTs). However, the patient prognosis is considerably less favorable if the disease recurs following failure of first-line therapies. There is a need for novel treatment options for patients with recurrent or metastatic TGCTs, notably for those that are not sensitive to first-line chemotherapy. With the development of next-generation sequencing technologies, an increasing number of gene mutations has been identified in TGCTs. Previously published research studies have established a link between KRAS mutations and chemotherapy resistance, and have demonstrated that KRAS mutations are associated with inflammatory tumor microenvironment and tumor immunogenicity, leading to an improved response to inhibition of programmed death (PD-1) protein expression. Previous studies have reported that the tumor immune microenvironment of TGCT influences therapeutic efficacy.

CASE PRESENTATION

A 65-year-old metastatic patient with TGCT and a KRAS-12 valine-for-glycine gene mutation was described. This patient initially underwent inguinal orchiectomy and received two prior chemotherapeutic regimens. Following the rapid progression of the disease, the patient was treated with anti-PD-1 therapy and nab-paclitaxel chemotherapy, and his condition was successfully controlled by this combination treatment.

CONCLUSION

To the best of our knowledge, this is the first successful case of KRAS-mutation patient with TGCT who achieved partially and sustained disease remission by combining immune checkpoint inhibitors with chemotherapy. This case provides an excellent example for personalized treatment of metastatic TGCTs.

A comprehensive analysis of the KLRB1 expression and its clinical implication in testicular germ cell tumors: A review

Testicular germ cell tumors (TGCT) are the most common testicular malignancies. KLRB1 is considered to influence the development and progression of a number of cancers. However, it is unclear how the KLRB1 gene functions in TGCT. First, it was determined the expression level of KLRB1 in TGCT using The Cancer Genome Atlas (TCGA) (The Cancer Genome Atlas) dataset and GTEx (Genotype-Tissue Expression) dataset. The clinical significance and biological functions of KLRB1 were explored using the TCGA dataset, and we analyzed the correlation of the KLRB1 gene with tumor immunity and infiltrating immune cells using gene set variation analysis and the TIMER database. We found that the expression level of KLRB1 was upregulated in TGCT malignant tissues with the corresponding normal tissues as controls, and KLRB1 expression correlated with clinicopathologic features of TGCT. Functional enrichment analysis suggested that KLRB1 might be involved in immune response and inflammatory response. KLRB1 was highly positively correlated with natural killer cell activation in immune response and positively correlated with tumor-infiltrating immune cells. This study demonstrated for the first time the role of KLRB1 in TGCT, which may serve as a new biomarker associated with immune infiltration and provide a potential therapeutic target for the treatment of TGCT.

Frequent expression of CD45RO memory T cell marker as well as low to high expression of PD-1 and PD-L1 inhibitory molecules in seminoma and dysgerminoma

BACKGROUND

Seminoma and dysgerminoma are rare testicular and ovarian germ cell tumors characterized by a significant infiltration of immune cells in the tumor microenvironment. According to the failure of conventional treatments in some patients, it is crucial to identify novel prognostic and therapeutic biomarkers for these patients. The objectives of this study were to evaluate the expression of CD45RO and PD-1/PD-L1 and investigate their association with the clinicopathological characteristics of the patients.

METHODS

Immunohistochemistry was performed to assess the expression of CD45RO, PD-1, and PD-L1 in tumor-infiltrated lymphocytes (TILs), and tumor cells in 33 seminoma and 31 dysgerminoma patients. The expression levels were evaluated using a semiquantitative approach, weighted histoscore, which considers both the intensity and extent of staining.

RESULTS

All seminoma and dysgerminoma patients exhibited CD45RO expression in TILs, with 66.7 % and 90.3 % displaying high levels of expression, respectively. PD-1 expression in TILs was observed at low levels in 81.8 % and 77.4 % and at high levels in 18.2 % and 19.4 % of seminoma and dysgerminoma patients, respectively. Likewise, low expression of PD-L1 in tumor cells was detected in 63.6 % of seminoma and 61.3 % of dysgerminoma patients, while none of the patients exhibited high expression of PD-L1. In seminoma patients, a positive correlation was observed between PD-1 expression in TILs and CD45RO expression and between PD-L1 expression in tumor cells and TILs score.

CONCLUSION

The frequent infiltration of CD45RO, along with variable expression of PD-1 and PD-L1 on TILs and tumor cells, could impact the effectiveness of anti-tumor responses and immunotherapy.

Pure testicular choriocarcinoma, a rare and highly malignant subtype with challenging treatment: A case report and review of the literature

Testicular choriocarcinoma (CC) is the rarest subtype of germ cell tumours (GCTs) of the testis, with a high malignant potential and early haematogenous metastasis. Radical surgical resection should be performed primarily for histological diagnosis, while chemotherapy remains the mainstay of therapy for advanced disease. In the present study, the case of a 65-year-old male patient diagnosed with metastatic testicular CC, who did not fully respond to chemotherapy is reported. This patient underwent surgical removal of the testicular tumour, chemotherapy with etoposide and cisplatin, and radiotherapy of the intracranial lesions. Although the serum human chorionic gonadotropin (HCG) levels of the patient and most of the metastases continued decreasing during chemotherapy, complete response was not achieved after six cycles of chemotherapy. The patient refused high-dose chemotherapy and autologous stem cell transplantation due to severe side effects, and eventually developed respiratory failure on maintenance therapy with oral etoposide. A literature review was then performed, aiming to summarize the characteristics and therapeutic principles of testicular CC. In addition, the emerging therapeutic agents that could be used in maintenance therapy for GCTs, particularly for testicular CC, were also discussed. The limited clinical trials of targeted treatments showed potential benefit for long survival of patients with selected GCTs with fewer side effects. In particular, immunotherapy showed unique potential for testicular CC in preclinical studies, offering new approaches of maintenance therapy for advanced disease. Further studies should shed light on the identification of prognostic factors that predict the response to immune-based therapy in GCTs.

Predictors of Testicular Cancer Mortality in Brazil: A 20-Year Ecological Study

Testicular cancer is common in young men, and early detection and multimodality treatment can lead to successful outcomes. This study aims to identify sociodemographic and risk factors associated with higher testicular cancer mortality and poorer survival rates, while examining the impact of diagnostic and treatment procedures on reducing mortality. The retrospective ecological study analyzed mortality data from testicular cancer in Brazil from 2001 to 2020. Sociodemographic variables such as marital status, age, birth period, year of death (cohort), race, and geographic region were assessed. Risk factors included cryptorchidism and pesticide exposure. Data were subjected to statistical analysis, which revealed an increasing trend in mortality after 2011 among persons born after 1976 in the 15-40 age group. Individuals in the South Region, whites, and singles had higher age-standardized mortality rates (ASMRs), while singles had lower survival rates. The Northeast region had a higher survival rate. Fungicides and insecticides increase ASMR in Brazil. Herbicides increase ASMR in the Northeast and Midwest regions and insecticides increase ASMR in the Northeast, Southeast, and Midwest regions. High rates of implementation of diagnostic procedures in the Midwest were not sufficient to reduce ASMR. No treatment procedure was associated with mortality at the national or regional level.

TAMs PD-L1(+) in the reprogramming of germ cell tumors of the testis

BACKGROUND

In recent years, several studies focused on the process of reprogramming of seminoma (S) cells, which regulates the transition from pure S (P-S) to S component (S-C) of mixed germ cell tumors of the testis (GCTT) and finally to embryonal carcinoma (EC) and other nonseminomatous GCTT (NS-GCTT). The accepted pathogenetic model is driven and regulated by cells (macrophages, B- and T-lymphocytes) and molecules of the tumor microenvironment (TME). Herein, we tested a series of GCTT with double staining (DS) for CD68-PD-L1 to evaluate tumor-associated macrophages (TAMs) expressing programmed death-ligand 1 (PD-L1) [TAMs PD-L1(+)] and clarify if these cells may be involved in establishing the fate of GCTT.

METHODS

We collected 45 GCTT (comprising a total of 62 different components of GCTT). TAMs PD-L1(+) were evaluated with three different scoring systems [TAMs PD-L1(+)/mm², TAMs PD-L1(+)/mm²H-score, TAMs PD-L1(+) %], and compared using pertinent statistic tests (Student's t-test and Mann-Whitney U test).

RESULTS

We found that TAMs PD-L1(+) values were higher in S rather than EC (p = 0.001, p = 0.015, p = 0.022) and NS-GCTT (p < 0.001). P-S showed statistically significant differences in TAMs PD-L1(+) values compared to S-C (p < 0.001, p = 0.006, p = 0.015), but there were no differences between S-C and EC (p = 0.107, p = 0.408, p = 0.800). Finally, we found statistically significant differences also in TAMs PD-L1(+) values between EC and other NS-GCTT (p < 0.001).

CONCLUSIONS

TAMs PD-L1(+) levels gradually decrease during the reprogramming of S cells {P-S [(high values of TAMs PD-L1(+)] → S-C and EC [(intermediate values of TAMs PD-L1(+)] → other NS-GCTT [(low values of TAMs PD-L1(+)], supporting a complex pathogenetic model where the interactions between tumor cells and TME components [and specifically TAMs PD-L1(+)] play a key role in determining the fate of GCTT.

Immunotherapy in Genitourinary Cancers: Role of Surgical Pathologist for Detection of Immunooncologic Predictive Factors

Genitourinary malignancies include a broad spectrum of distinct tumor entities occurring in the kidney, the urinary tract, the prostate, the adrenal glands, the penis, and testicles. Each tumor entity presents with unique biological characteristics, especially in terms of immunobiology. The immune landscape of genitourinary malignancies differs between immunoreactive tumors like urothelial carcinoma or carcinomas of the kidney, for which several immunotherapeutic treatment options have been approved in the past years. In contrast, prostate cancer presents with low immunogenicity and previous trials exploring immune checkpoint inhibitors and other immunotherapeutic agents did not proof substantial survival benefits. In this review, we are presenting a streamlined overview on the role of surgical pathologists within the contemporary practice of immune oncology. It includes current indications for pathologic programmed death-ligand 1 (PD-L1) assessment and important pathologic considerations on PD-L1 testing harmonization including interassay and algorithm variabilities. In addition, we will discuss emerging biomarkers beyond PD-L1 and their potential to predict immunotherapy responses including tumor mutational burden, microsatellite instability, gene expression signatures, and histologic factors.

Long non-coding RNA TTTY14 promotes cell proliferation and functions as a prognostic biomarker in testicular germ cell tumor

Testicular germ cell tumors (TGCTs) commonly occur in males between the ages of 15 and 34, accounting for 98% of testicular malignancies. Long non-coding RNAs (LncRNAs) have been reported to play important roles in TGCT proliferation, invasion, and functioned as prognostic biomarkers. Testis-specific transcript, Y-linked 14 (TTTY14), a long non-coding RNA localized on Chr Y q11.222, has been found to be a potential prognostic biomarker for laryngeal squamous cell carcinoma, gastric cancer, and osteosarcoma. The biological role of TTTY14 in TGCT is not well understood. In this study, we aim to clarify the biological role of TTTY14 in TGCT, as well as its role in TGCT survival prognosis and immunotherapy efficacy prediction through the deep mining of public data combined with the verification of cell biological experiments. We found that high TTTY14 expression was a poor survival prognostic factor in TGCT patients and the expression of TTTY14 might be regulated by copy number variation and DNA methylation. TTTY14 knockdown significantly inhibited the proliferation of TGCT in vitro. TTTY14 expression was positively correlated with immune cell dysfunction, and significantly negatively correlated with B cells, CD8⁺ T cells, and macrophages, suggesting that TTTY14 may also affect the drug sensitivity by regulating the tumor immune microenvironment. In conclusion, we revealed that lncRNA TTTY14 was a novel oncogene and a biomarker in TGCT. TTTY14 may influence the drugs sensitivity through regulating the tumor immune microenvironment.

Pediatric Extracranial Germ Cell Tumors: Review of Clinics and Perspectives in Application of Autologous Stem Cell Transplantation

Pediatric extracranial germ cell tumors (GCTs) are rare, accounting for approximately 3.5% of childhood cancers. Since the introduction of platinum-based chemotherapy, the survival rate of patients has improved to more than 80%. However, poor-risk subtypes of pediatric extracranial GCTs do not respond well to chemotherapy, leading to refractory or relapsed (R/R) diseases. For example, long-term survival rates of mediastinal GCTs or choriocarcinoma are less than 50%. According to reports in recent years for adult patients with R/R GCTs, the use of high-dose chemotherapy (HDCT) combined with autologous stem cell transplantation (ASCT) has clinical advantages; however, HDCT combined with ASCT has rarely been reported in pediatric GCTs. The R/R and poor-risk groups of pediatric GCTs could benefit from HDCT and ASCT.

Seminoma subtypes differ in the organization and functional state of the immune microenvironment

Seminoma is the most common type of testicular germ cell tumors (TGCTs) among 15-44 years old men. Seminoma treatments include orchiectomy, platinum-based chemotherapy and radiotherapy. These radical treatment methods cause up to 40 severe adverse long-term side effects including secondary cancers. Immunotherapy based on immune checkpoint inhibitors, which showed its efficiency for many types of cancer, can be important alternative to the platinum-based therapy for seminoma patients. However, five independent clinical trials evaluating the efficiency of immune checkpoint inhibitors for TGCTs treatment were shut down at the phase II due to lacking clinical efficacy and detailed mechanisms of this phenomena are yet to be discovered. Recently we identified two distinct seminoma subtypes based on transcriptomic data and here we focused on the analysis of seminoma microenvironment and its subtype-specific characteristics. Our analysis revealed that less differentiated subtype 1 of seminoma has immune microenvironment with significantly lower immune score and larger fraction of neutrophils. Both are features of the immune microenvironment at an early developmental stage. On the contrary, subtype 2 seminoma is characterized by the higher immune score and overexpression of 21 genes related to senescence-associated secretory phenotype. Seminoma single cell transcriptomic data showed that 9 out of 21 genes are predominantly expressed in immune cells. Therefore, we hypothesized that senescence of immune microenvironment can be one of the reasons for seminoma immunotherapy failure.

Supplementary Information

The online version contains supplementary material available at 10.1007/s13205-023-03530-1.

Immune checkpoint inhibitors and Chimeric Antigen Receptor (CAR)-T cell therapy: Potential treatment options against Testicular Germ Cell Tumors

Germ cell tumors (GCTs) represent a heterogeneous neoplasm family affecting gonads and rarely occurring in extragonadal areas. Most of patients have a good prognosis, often even in the presence of metastatic disease; however, in almost 15% of cases, tumor relapse and platinum resistance are the main challenges. Thus, novel treatment strategies with both improved antineoplastic activity and minor treatment-related adverse events compared with platinum are really expected. In this context, the development and the high activity demonstrated by immune checkpoint inhibitors in solid tumors and, subsequently, the interesting results obtained from the use of chimeric antigen receptor (CAR-) T cell therapy in hematological tumors, have stimulated research in this direction also in GCTs. In this article, we will analyze the molecular mechanisms underlying the immune action in the development of GCTs, and we will report the data from the studies that tested the new immunotherapeutic approaches in these neoplasms.

Brain and Spinal Tumors Originating from the Germ Line Cells

Primary central nervous system germ cell tumors (CNS GCTs) are part of the GCTs in children and adults. This tumor entity presents with geographic variation, age, and sex predilection. There are two age peaks of incidence distribution at the first few months of life and in adolescence. CNS GCTs are heterogeneous in histopathological subtypes, locations, and tumor marker (AFP, β-hCG) secretions. In the WHO CNS tumor classification, GCTS are classified as germinoma and nongerminomatous GCT (NGGCT) with different subtypes (including teratoma). Excluding mature teratoma, the remaining NGGCTs are malignant (NGMGCT). In teratoma, growing teratoma syndrome and teratoma with somatic-type malignancy should be highlighted. The common intracranial locations are pineal region, neurohypophysis (NH), bifocal pineal-NH, basal ganglia, and cerebral ventricle. Above 50% of intracranial GCTs (IGCTs) present obstructive hydrocephalus. Spinal tumors are rare. Age, locations, hydrocephalus, and serum/CSF titer of β-hCG correlate with clinical manifestations. Delayed diagnosis is common in tumors arising in neurohypophysis, bifocal, and basal ganglia resulting in the increasing of physical dysfunction and hormonal deficits. Staging work-up includes CSF cytology for tumor cells and contrast-enhanced MRI of brain and spine for macroscopic metastasis before treatment commences. The therapeutic approach of CNS GCTs integrates locations, histopathology, staging, tumor marker level, and therapeutic classification. Treatment strategies include surgical biopsy/excision, chemotherapy, radiotherapy (single or combination). Secreting tumors with consistent imaging may not require histopathological diagnosis. Primary germinomas are highly radiosensitive and the therapeutic aim is to maintain high survival rate using optimal radiotherapy regimen with/without chemotherapy combination. Primary NGNGCTs are less radiosensitive. The therapeutic aim is to increase survival utilizing more intensive chemotherapy and radiotherapy. The negative prognostic factors are residue disease at the end of treatment and serum or CSF AFP level >1000 ng/mL at diagnosis. In refractory or recurrent NMGGCTs, besides high-dose chemotherapy, new therapy is necessary. Molecular profiling and analysis help for translational research. Survivors of pediatric brain tumors frequently experience cancer-related cognitive dysfunction, physical disability, pituitary hormone deficiency, and other CNS complications after cranial radiotherapy. Continuous surveillance and assessment may lead to improvements in treatment protocols, transdisciplinary interventions, after-treatment rehabilitation, and quality of life.

Identification of novel potential genes in testicular germ cell tumors: A transcriptome analysis

OBJECTIVE

Testicular germ cell tumors (TGCTs), containing pure seminoma and non-seminoma, occupy the most majority of testicular cancers in adolescents and young men, which has increased dramatically in recent decades. Therefore, it is important to find crucial genes for improving diagnosis and prognosis in TGCTs. However, the diagnostic and prognostic markers of TGCTs are limited.

METHODS

In this study, our main objective is to explore novel potential genes that can be used as diagnostic and prognostic biomarkers in TGCTs. Our study detected 732 differentially expressed genes (DEGs) using three microarray expression profiling datasets from Gene Expression Omnibus (GEO). Multiple analysis was performed to identify the roles of DEGs, including pathway and functional enrichment analysis, protein-protein interaction (PPI) network analysis, module analysis, and survival analysis.

RESULT

In total, 322 upregulated genes and 406 downregulated genes were identified as DEGs The functional and pathway enrichment analysis shows that DEGs were highly enriched in multiple biological attributes such as T cell activation, reproduction in multicellular organism, sperm flagellum, antigen processing and presentation Then, seven potential crucial genes were identified via PPI network analysis, module analysis, and survival analysis. Furthermore, 7 potential crucial genes had shown to play a key role in regulating immune cell infiltration level in patients with TGCTs.

CONCLUSION

We identified seven potential crucial genes (LAPTM5, NCF2, PECAM1, CD14, COL4A2, ANPEP and RGS1), which may be molecular markers in improving the way of diagnosis and prognosis in TGCTs.

Immune-related mechanisms and immunotherapy in extragonadal germ cell tumors

Purpose of review

Extragonadal germ cell tumors (EGCTs) are relatively rare tumors, accounting for 1%-5% of all GCTs. In this review, we summarize the current research progress regarding the pathogenesis, diagnosis, and treatment of EGCTs from an immunology perspective.

Recent findings

The histological origin of EGCTs is related to a gonadal origin, but they are located outside the gonad. They show great variation in morphology and can occur in the cranium, mediastinum, sacrococcygeal bone, and other areas. The pathogenesis of EGCTs is poorly understood, and their differential diagnosis is extensive and challenging. EGCT behavior varies greatly according to patient age, histological subtype, and clinical stage.

Summary

This review provides ideas for the future application of immunology in the fight against such diseases, which is a hot topic currently.

FGF9 promotes cell proliferation and tumorigenesis in TM3 mouse Leydig progenitor cells

Fibroblast growth factor 9 (FGF9) modulates cell proliferation, differentiation and motility for development and tissue repair in normal cells. Growing evidence shows that abnormal activation of FGF9 signaling is associated with tumor malignancy. We have previously reported that FGF9 increases MA-10 mouse Leydig tumor cell proliferation, in vitro, and tumor growth, in vivo. Also, FGF9 promotes the tumor growth and liver metastasis of mouse Lewis lung cancer cells, in vivo. However, the effects of FGF9 in the early stage of tumorigenesis remains elusive. In this study, TM3 mouse Leydig progenitor cells, that are not tumorigenic in immunocompromised mice, were used as a model cell line to investigate the role of FGF9 in tumorigenesis. The results demonstrated that FGF9 significantly induced cell proliferation and activated the MAPK, PI3K and PLCγ signaling pathways in TM3 cells. The percentage of the cell number in G1 phase was reduced and that in S and G2/M phases was increased after FGF9 stimulation in TM3 cells. Cyclin D1, cyclin A1, CDK2, CDK1, and p21 expressions and the phosphorylation level of Rb were all induced in FGF9-treated TM3 cells. In addition, FGF9 increased the expression of FGF receptor 1-4 in TM3 cells, suggesting the positive feedback loop between FGF9 and FGFRs. Furthermore, in the allograft mouse model, FGF9 promoted the tumorigenesis of TM3 cells characterized by higher expression of tumor markers, such as tumor necrosis factor alpha (TNFα) and α-fetoprotein (AFP), in the subcutaneously inoculated TM3 cell tissue. Conclusively, FGF9 induced cell cycle to increase cell proliferation of TM3 cells through FAK, MAPK, PI3K/Akt and PLCγ signaling pathways, in vitro, and promoted the tumorigenesis of TM3 cell allograft tissue, in vivo, which is a potential marker for tumor as well as a target for cancer therapeutic strategies.

PD-L1 and PD-1 expression in pediatric central nervous system germ cell tumors

Central nervous system (CNS) germ cell tumors (GCTs) represent 2-3% of all primary CNS tumors. The majority are germinomas, which are radiosensitive and have an excellent prognosis. Contrarily, CNS non-germinomatous GCTs (NGGCTs) have less favorable prognosis and require more aggressive treatment. The expression of checkpoint/immune markers in CNS GCTs, particularly NGGCTs, is unknown. We previously reported a case of a patient whose intracranial NGGCT (predominantly choriocarcinoma) responded to immune checkpoint inhibition therapy. This case led us to evaluate our archive of intracranial GCTs for expression of PD-L1 and PD-1. With IRB approval, we searched the pathology archives at our institution for CNS GCTs. Demographic, radiologic, clinical, and histologic information was extracted from the medical records. Immunohistochemistry for lymphocytic markers (CD4, CD8, CD20), PD-1, and PD-L1 was performed. PD-L1 was considered positive if greater than 1% of tumor cells were positive and PD-1 was reported as a percentage of positive inflammatory cells. Fifty cases were identified, including 28 germinomas (mean age at diagnosis: 15.5 years; 17 males, 11 females), and 22 NGGCTs (mean age at diagnosis: 12.0 years, 21 males, 1 female). Germinomas were mostly suprasellar (17/28) and NGGCTs were predominantly pineal (17/22). Twenty-two germinomas (79%) were positive for PD-L1 expression, and 13 NGGCTs (57%) were positive for PD-L1. Cases of choriocarcinoma showed the most diffuse PD-L1 expression. PD-1 expression was seen in lymphocytes among 27/28 of the germinomas and 20/23 of the NGGCTs (ranging from 1-40% of lymphocytes). As expected, larger quantities of inflammatory cells were present in cases of germinoma. We demonstrate immune activity in CNS GCTs, and our results suggest that immune checkpoint inhibitors may be efficacious in the treatment of intracranial GCTs. Among NGGCTs, cases of choriocarcinoma showed the highest expression of PD-L1 in tumor cells, suggesting that this subtype may have the greatest benefit from checkpoint blockade.

Hodentumoren aus klinischer Sicht

Hintergrund

Keimzelltumoren des Hodens sind die häufigste maligne Tumorerkrankung bei Männern im Alter von 15–40 Jahren. Die Unterscheidung von Seminomen und Nichtseminomen hat prognostische Bedeutung und ist für Therapieplanung und Nachsorge essenziell. Durch interdisziplinäre, stadiengerechte Therapie haben Keimzelltumoren generell eine sehr gute Prognose. Eine Übertherapie sollte wegen möglicher Langzeitfolgen vermieden werden. Hierbei hilft die Risikobeurteilung anhand klinischer und pathologischer Faktoren.

Ziel der Arbeit

Darstellung der (histo-)pathologischen Charakteristika, die die uroonkologische Therapieplanung maßgeblich beeinflussen.

Material und Methoden

Nichtsystematischer Übersichtsartikel über die relevanten (histo-)pathologischen Befunde für die klinische Therapieplanung im interdisziplinären Kontext.

Ergebnisse

Zentrale Pathologiebefunde für Kliniker:Innen sind: (i) Identifikation eines Keimzelltumors, ggf. durch Nachweis eines Chromosom-12p-Zugewinns, (ii) Subtypenspezifizierung und (iii) Angabe von Risikofaktoren (insbesondere Invasion von Lymphgefäßen und/oder Rete testis und Tumorgröße). Molekularpathologische Untersuchungen i. S. von Mutationsanalysen sind angesichts einer sehr geringen Mutationslast und bislang fehlender prädiktiver Marker und zielgerichteter Therapieoptionen nicht Teil der Routinediagnostik.

Diskussion

Ein detaillierter, idealerweise synoptischer histopathologischer Befundbericht ist Grundlage der Planung und Durchführung einer leitlinienkonformen, risikoadaptierten Therapie und neben der bildgebenden Diagnostik und der Bestimmung der Serumtumormarker AFP und β‑HCG (letztere insbesondere bei Nichtseminomen) mitentscheidend, um die guten Heilungsaussichten zu wahren und eine Übertherapie zu vermeiden.

Testicular yolk sac tumour metastasis to the L2 vertebra

The role of surgery for metastases to the vertebra from yolk sac tumours has not been established. The main treatment for disseminated disease is chemotherapy. We present a man in his 30s with a left orchiectomy for a testicular mixed germ cell tumour with a prominent yolk sac component who, 12 months later, developed an asymptomatic metastasis to the L2 vertebra unresponsive to chemotherapy and radiotherapy. The patient underwent resection of the L2 vertebral body, leaving a small residual tumour anterior to the vertebra attached to the great vessels. Pathology confirmed the diagnosis of a metastatic testicular yolk sac tumour in the vertebra. The postoperative MRI 6 months later demonstrated significant expansion of the tumour at the soft tissues anterior to the expandable titanium cage encasing the great vessels and extending to the paraspinal areas. Additional salvage surgery was not recommended because of the advanced stage of the tumour.

Inflammatory Biomarkers for Outcome Prediction in Patients With Metastatic Testicular Cancer

Germ cell tumors are the most common malignant tumors in male young adults. Platinum-based chemotherapy has dramatically improved the outcome of metastatic germ cell tumor patients and overall cure rates now exceed 80%. The choice of medical treatment can be guided by the prognosis estimation which is an important step during the decision-making process. IGCCCG classification plays a pivotal role in the management of advanced disease. However, histological and clinical parameters are the available factors that condition the prognosis, but they do not reflect the tumor's molecular and pathological features and do not predict who will respond to chemotherapy. After first-line chemotherapy 20%-30% of patients relapse and for these patients, the issue of prognostic factors is far more complex. Validated biomarkers and a molecular selection of patients that reflect the pathogenesis are highly needed. The association between cancer-related systemic inflammation, tumorigenesis, and cancer progression has been demonstrated. In the last years, several studies have shown the prognostic utility of immune-inflammation indexes in different tumor types. This review analyzed the prognostic impact of inflammatory markers retrieved from routine blood draws in GCT patients.

Identification of Potential Biomarkers for Pan-Cancer Diagnosis and Prognosis Through the Integration of Large-Scale Transcriptomic Data

Cancer is one of the leading causes of death worldwide, bringing a significant burden to human health and society. Accurate cancer diagnosis and biomarkers that can be used as robust therapeutic targets are of great importance as they facilitate early and effective therapies. Shared etiology among cancers suggests the existence of pan-cancer biomarkers, performance of which could benefit from the large sample size and the heterogeneity of the studied patients. In this study, we conducted a systematic RNA-seq study of 9,213 tumors and 723 para-cancerous tissue samples of 28 solid tumors from the Cancer Genome Atlas (TCGA) database, and 7,008 normal tissue samples from the Genotype-Tissue Expression (GTEx) database. By differential gene expression analysis, we identified 214 up-regulated and 186 downregulated differentially expressed genes (DEGs) in more than 80% of the studied tumors, respectively, and obtained 20 highly linked up- and downregulated hub genes from them. These markers have rarely been reported in multiple tumors simultaneously. We further constructed pan-cancer diagnostic models to classify tumors and para-cancerous tissues using 10 up-regulated hub genes with an AUC of 0.894. Survival analysis revealed that these hub genes were significantly associated with the overall survival of cancer patients. In addition, drug sensitivity predictions for these hub genes in a variety of tumors obtained several broad-spectrum anti-cancer drugs targeting pan-cancer. Furthermore, we predicted immunotherapy sensitivity for cancers based on tumor mutational burden (TMB) and the expression of immune checkpoint genes (ICGs), providing a theoretical basis for the treatment of tumors. In summary, we identified a set of biomarkers that were differentially expressed in multiple types of cancers, and these biomarkers can be potentially used for diagnosis and used as therapeutic targets.

Testicular Germ Cell Tumours and Proprotein Convertases

Simple Summary

Despite the high survival rate of the most common neoplasia in young Caucasian men: Testicular Germ Cell Tumors (TGCT), the quality of life of these patients is impaired by the multiple long-term side effects of their treatment. The study of molecules that can serve both as diagnostic biomarkers for tumor development and as therapeutic targets seems necessary. Proprotein convertases (PC) are a group of proteases responsible for the maturation of inactive proproteins with very diverse functions, whose alterations in expression have been associated with various diseases, such as other types of cancer and inflammation. The study of the immune tumor microenvironment and the substrates of PCs could contribute to the development of new and necessary immunotherapies to treat this pathology.

Abstract

Testicular Germ Cell Tumours (TGCT) are widely considered a “curable cancer” due to their exceptionally high survival rate, even if it is reduced by many years after the diagnosis due to metastases and relapses. The most common therapeutic approach to TGCTs has not changed in the last 50 years despite its multiple long-term side effects, and because it is the most common malignancy in young Caucasian men, much research is needed to better the quality of life of the many survivors. Proprotein Convertases (PC) are nine serine proteases responsible for the maturation of inactive proproteins with many diverse functions. Alterations in their expression have been associated with various diseases, including cancer and inflammation. Many of their substrates are adhesion molecules, metalloproteases and proinflammatory molecules, all of which are involved in tumour development. Inhibition of certain convertases has also been shown to slow tumour formation, demonstrating their involvement in this process. Considering the very established link between PCs and inflammation-related malignancies and the recent studies carried out into the immune microenvironment of TGCTs, the study of the involvement of PCs in testicular cancer may open up avenues for being both a biomarker for diagnosis and a therapeutic target.

ImReLnc: Identifying Immune-Related LncRNA Characteristics in Human Cancers Based on Heuristic Correlation Optimization

Long non-coding RNAs (lncRNAs) play critical roles in cancer through gene expression and immune regulation. Identifying immune-related lncRNA (irlncRNA) characteristics would contribute to dissecting the mechanism of cancer pathogenesis. Some computational methods have been proposed to identify irlncRNA characteristics in human cancers, but most of them are aimed at identifying irlncRNA characteristics in specific cancer. Here, we proposed a new method, ImReLnc, to recognize irlncRNA characteristics for 33 human cancers and predict the pathogenicity levels of these irlncRNAs across cancer types. We first calculated the heuristic correlation coefficient between lncRNAs and mRNAs for immune-related enrichment analysis. Especially, we analyzed the relationship between lncRNAs and 17 immune-related pathways in 33 cancers to recognize the irlncRNA characteristics of each cancer. Then, we calculated the Pscore of the irlncRNA characteristics to evaluate their pathogenicity levels. The results showed that highly pathogenic irlncRNAs appeared in a higher proportion of known disease databases and had a significant prognostic effect on cancer. In addition, it was found that the expression of irlncRNAs in immune cells was higher than that of non-irlncRNAs, and the proportion of irlncRNAs related to the levels of immune infiltration was much higher than that of non-irlncRNAs. Overall, ImReLnc accurately identified the irlncRNA characteristics in multiple cancers based on the heuristic correlation coefficient. More importantly, ImReLnc effectively evaluated the pathogenicity levels of irlncRNAs across cancer types. ImReLnc is freely available at https://github.com/meihonggao/ImReLnc.

Immune Checkpoint Inhibitors for Genitourinary Cancers: Treatment Indications, Investigational Approaches and Biomarkers

Cancers of the genitourinary (GU) tract are common malignancies in both men and women and are a major source of morbidity and mortality. Immune checkpoint inhibitors (ICI) targeting CTLA-4, PD-1 or PD-L1 have provided clinical benefit, particularly in renal cell and urothelial carcinoma, and have been incorporated into standard of care treatment in both localized and metastatic settings. However, a large fraction of patients do not derive benefit. Identification of patient and tumor-derived factors which associate with response have led to insights into mechanisms of response and resistance to ICI. Herein, we review current approvals and clinical development of ICI in GU malignancies and discuss exploratory biomarkers which aid in personalized treatment selection.

Combined Assessment of Immune Checkpoint Regulator VISTA on Tumor-Associated Immune Cells and Platelet-to-Lymphocyte Ratio Identifies Advanced Germ Cell Tumors with Higher Risk of Unfavorable Outcomes

Simple Summary

Testicular germ cell tumors (GCTs) are the most common malignancies in young males. The current treatment regimens are usually highly effective and curative. Nevertheless, a portion of patients presents with recurrence or succumbs due to the disease. There is an undoubtful necessity to investigate new prognostic markers to stratify the risk of such events. The current study aimed to evaluate the prognostic significance of markers of the tumor microenvironment and systemic inflammation markers in GCTs. We found that low expression of immune checkpoint proteins VISTA (V-domain Ig suppressor of T cell activation) and PD-L1 (programmed death-ligand 1) on tumor-associated immune cells and elevated inflammatory marker platelet-to-lymphocyte ratio are associated with a higher risk of events in testicular GCTs. It indicates a role of both local anti-tumor immune response and systemic inflammation in these tumors.

Abstract

In the current study, we aimed to investigate whether expression of immune checkpoint proteins (V-domain Ig suppressor of T cell activation (VISTA) and programmed death-ligand 1 (PD-L1)) and markers of systemic inflammation could predict progression/relapse and death in the cohort of 180 patients with testicular germ-cell tumors (GCTs). Expression of PD-L1 and VISTA was assessed by immunohistochemistry utilizing tissue microarrays. To estimate systemic inflammation neutrophil-to-lymphocyte ratio (NLR), lymphocyte-to-monocyte ratio (LMR), and platelet-to-lymphocyte ratio (PLR) were calculated. We found high PD-L1 and VISTA expression on tumor-associated immune cells (TAICs) in 89 (49.44%) and 63 (37.22%) of GCTs, respectively, whereas tumor cells besides trophoblastic elements were almost uniformly negative. High PD-L1 was associated with seminomatous histology and lower stage. Relapses in stage I patients occurred predominantly in cases with low numbers of PD-L1 and VISTA-expressing TAICs. In stage II/III disease, the combination of low VISTA-expressing TAICs and high PLR was identified as predictor of shorter event-free survival (HR 4.10; 1.48–11.36, p = 0.006) and overall survival (HR 15.56, 95% CI 1.78–135.51, p = 0.001) independently of tumor histology and location of metastases. We demonstrated that the assessment of immune checkpoint proteins on TAICs may serve as a valuable prognostic factor in patients with high-risk testicular GCTs. Further study is warranted to explore the predictive utility of these biomarkers in GCTs.

Liquid Biopsies in the Clinical Management of Germ Cell Tumor Patients: State-of-the-Art and Future Directions

Liquid biopsies constitute a minimally invasive means of managing cancer patients, entailing early diagnosis, follow-up and prediction of response to therapy. Their use in the germ cell tumor field is invaluable since diagnostic tissue biopsies (which are invasive) are often not performed, and therefore only a presumptive diagnosis can be made, confirmed upon examination of the surgical specimen. Herein, we provide an overall review of the current liquid biopsy-based biomarkers of this disease, including the classical, routinely used serum tumor markers—the promising microRNAs rapidly approaching the introduction into clinical practice—but also cell-free DNA markers (including DNA methylation) and circulating tumor cells. Finally, and importantly, we also explore novel strategies and challenges for liquid biopsy markers and methodologies, providing a critical view of the future directions for liquid biopsy tests in this field, highlighting gaps and unanswered questions.

[What does the oncologist need from the pathologist in testicular cancer?]

BACKGROUND

Testicular type II germ cell tumours (GCTs) are an exemplar of a curable cancer and the most common malignancy in males aged ≤35 years. Even in metastatic stages, about 70% of patients can be cured by cisplatin-based chemotherapy and multimodal treatments. For patients failing platinum-based standard therapy, prognosis is poor and novel biomarkers and therapeutic options are urgently needed.

OBJECTIVES

Discussion of desired histopathological information to guide urologists' and oncologists' decision making in the treatment of male GCTs.

MATERIAL AND METHODS

A narrative review of histopathological key features of male GCT tissue samples for clinical decision making.

RESULTS

Histopathological workup is crucial to identify (i) a GCT origin in cancers of unknown primary based on isochromosome 12p (i(12p)) detection, (ii) the different type II GCT subtypes, and (iii) risk factors, i.e. lymphovascular or rete testis invasion, among others. Proper histopathological diagnosis is indispensable for guideline-endorsed, histology-driven, and risk-adapted treatment decisions, hereby helping to maintain treatment success while reducing the therapeutic burden and potential long-term sequelae of multimodal treatments. For refractory patients failing standard treatment options, prognosis remains poor and, so far, neither predictive or prognostic biomarkers nor novel therapeutic targets have been established.

CONCLUSIONS

Close interaction and interdisciplinary discussion of histopathologic and radiologic findings and established risk factors including serum tumour markers is crucial for successful treatment including intensified strategies, where necessary, or prevention of overtreatment, where possible.