Germ cell tumors (GCTs) are rare in childhood, representing only 3.5% of childhood cancers, but a common malignancy in adolescents and young adults (AYAs), accounting for 13.9% of neoplasms in adolescents between age 15 and 19 years. The overall outcomes of patients treated for GCTs are excellent. However, as seen in other cancers, outcomes for AYA patients are significantly worse. Understanding the reasons for this observation has led to different approaches to diagnosis, staging, and treatment. The Malignant Germ Cell International Consortium was created to bring together pediatric, gynecologic, and testicular cancer specialists to promote research initiatives and provide evidence-based approaches in the management of GCTs across different age groups. Collaboration between multiple subspecialties is essential to further understand the disease continuum, the underlying biologic characteristics, and the development of appropriate therapeutic approaches. This review focuses on the unique characteristics of patients with extracranial GCTs in the AYA group.

Ovarian cancer (OC) is a heterogeneous disease and a mounting body of evidence shows that a 'one-size-fits-all' approach is obsolete. Differences in epidemiology, tumor biology, genetic profiles and treatment responses of these different types necessitate a tumor and patient-specific approach. Ninety percentage consists of epithelial OC with 70% being high-grade serous OC. The other rarer subtypes are low-grade serous (5%), clear cell (12%), endometrioid (11%) and mucinous carcinoma (3%). The remaining 10% are nonepithelial rare OCs: germ cell (3%) and sex-cord stromal tumors (7%).Over the past few decades, the 5-year survival rates have only improved modestly, therefore novel therapies are urgently needed. Recently, immunotherapy has been introduced into clinical practice in a number of solid tumors. Although preclinical data confirm the presence of an immunogenic microenvironment in a number of ovarian tumor types, no single-agent immune checkpoint inhibitor has been approved hitherto. Identifying suitable treatment combinations, adequate patient selection and thus correct implementation of immunotherapy remain major challenges.In this review, we focus on the rationale of incorporating immune therapy in rare OC, we summarize the recent developments with preclinical data and results of clinical trials, with particular focus on rare ovarian histological subtypes.Copyright © 2021 Wolters Kluwer Health, Inc. All rights reserved.

The germ-cell tumours are a fascinating group of neoplasms because of their unusual biology and the spectacular therapeutic results that have been obtained in these tumours. Traditionally, this group of neoplasms is presented in an organ-oriented approach. However, recent clinical and experimental data convincingly demonstrate that these neoplasms are one disease with separate entities that can manifest themselves in different anatomical sites. We propose five entities, in which the developmental potential is determined by the maturation stage and imprinting status of the originating germ cell. Recent progress begins to explain the apparent unpredictable development of germ-cell tumours and offers a basis for understanding their exquisite sensitivity to therapy.

In recent years, our knowledge of ovarian germ cell tumors has increased, and their classification has evolved. The introduction of cisplatin-based chemotherapy and the discovery of tumor markers, including alpha-fetoprotein and human chorionic gonadotropin, have dramatically changed the clinical outlook for most of these patients. In this review, recent advances in the classification and pathology of ovarian germ cell tumors are discussed. Where appropriate, comparisons are made with testicular germ cell tumors. The last section of the article discusses the pathogenesis of germ cell tumors. This review will emphasize the articles written in the last 10 years and those that have significantly advanced our knowledge of germ cell tumors in past decades.

Fifty patients with disseminated testicular cancer were treated with a three-drug combination consisting of cis-diamminedichloroplatinum, vinblastine, and bleomycin. Three patients were considered inevaluable due to early death. This chemotherapy regimen produced 74% complete and 26% partial remissions. Furthermore, five patients with partial remission became disease-free after surgical removal of residual disease, producing an overall 85% disease-free status. Toxicity, although significant during remission induction with cis-platinum, vinblastine, and bleomycin, was usually manageable, although there were two drug-related deaths during this period. Thirty-eight of these patients remain alive and 32 remain alive and disease-free at 6 + to 30 + months. We believe this regimen represents a major advance in the management of patients with disseminated testicular cancer.

Malignant ovarian germ cell tumors are rare and knowledge about prognostic parameters currently is limited. This study was undertaken to evaluate long-term outcome of patients with malignant ovarian germ cell tumors (MOGCTs) after chemotherapy and to assess prognostic parameters.A total of 113 patients with stage IC to IV MOGCTs were included into this retrospective study. Patients were treated at two large regional cancer centers between 1977 and 2003.Ten-year recurrence-free and overall survival rates were 82% and 81%, respectively. A total of 20 patients experienced relapse, all within the first 8 years. Outcome after relapse was poor, with only 10% of patients achieving long-term survival. Univariate and multivariate analyses demonstrated that initial stage of disease (relative risk [RR], 5.96; 95% CI, 3.47 to 10.22; P =.03) and elevation of serum markers beta-human chorionic gonadotropin and alpha-fetoprotein (RR, 3.90; 95% CI, 1.40 to 10.9; P =.009) were significant predictors of overall survival, whereas age at diagnosis was of no prognostic value.This is the first study to identify stage and tumor markers as prognostic parameters for patients with MOGCTs. This might help to select patients for risk-adapted treatment. There is need for improvement of therapeutic strategies after relapse.

Refractory germ cell tumor (GCT) patients have a poor prognosis and limited treatment options. The identification of novel active agents may be impaired by use of response as the primary endpoint in phase 2 trials. Improved endpoints could enhance the development of new effective agents.The characteristics and outcome of refractory GCT patients enrolled in 7 single-agent phase 2 trials conducted at Memorial Sloan-Kettering Cancer Center from 1990 to 2008 were reviewed. The study agents were suramin, all-transretinoic acid, topotecan, pyrazoloacridine, temozolomide, ixabepilone, and sunitinib. The major endpoints evaluated were response, progression-free survival (PFS), and overall survival (OS).Ninety patients (87 male, 3 female) were treated. The primary tumor site was testis in 65 patients, mediastinum in 17 patients, retroperitoneum in 4 patients, and other in 4 patients. Eighty-six patients had nonseminoma, and 4 patients had pure seminoma. Best responses were 1 (1%) partial response (ixabepilone), 15 (17%) stable disease, and 74 (82%) progressive disease. Median PFS and OS were 1.0 month (95% confidence interval [CI], 0.8-1.3) and 4.7 months (95% CI, 3.5-6.4), respectively. Eighty-six of the 90 patients have died. The 12- and 16-week PFS rates were 9% (95% CI, 3-15%) and 6% (95% CI, 1%-11%), respectively.Patients with refractory GCT progressed rapidly to these single agents. PFS and OS may be useful endpoints for designing phase 2 trials testing novel agents in this population. Twelve-week PFS (with comparison to the 9% benchmark rate reported herein) is the recommended endpoint for phase 2 trial design and median OS (using 4.7 months as the predicted median for the control arm) is suggested for phase 3 trials.Copyright © 2011 American Cancer Society.

Most patients with metastatic germ-cell cancer (GCC) can be cured by cisplatin-based combination chemotherapy. Yet, about 10-15% of metastatic GCC patients will eventually die of their disease. This narrative review focuses on treatment options when cure is no longer realistic.Copyright © 2018 The Authors. Published by Elsevier Ltd.. All rights reserved.

Testicular germ cell tumors (TGCTs) belong to the most chemosensitive solid tumors; however, a small proportion of patients fail to be cured with cisplatin-based chemotherapy. Inhibitors of PD-1/PD-L1 pathways represent a new class of promising drugs in anticancer therapy. The aim of this study was to evaluate expression and prognostic value of PD-1 and PD-L1 in TGCTs.Surgical specimens from 140 patients with TGCTs (131 with primary testicular tumor and 9 with extragonadal GCTs) were included into the translational study. PD-1 and PD-L1 expression was detected in the tumor tissue by immunohistochemistry using monoclonal antibodies, scored by the multiplicative quickscore (QS) method, compared with their expression in normal testicular tissue and correlated with clinicopathological characteristics and clinical outcome.None of the GCTs exhibited PD-1 protein, although expression of PD-L1 was significantly higher in GCTs in comparison with normal testicular tissue (mean QS = 5.29 versus 0.32, P < 0.0001). Choriocarcinomas exhibit the highest level of PD-L1 with decreasing positivity in embryonal carcinoma, teratoma, yolk sac tumor and seminoma. PD-L1 expression was associated with poor prognostic features, including ≥3 metastatic sites, increased serum tumor markers and/or non-pulmonary visceral metastases. Patients with low PD-L1 expression had significantly better progression-free survival [hazard ratio (HR) = 0.40, 95% confidence interval (CI) 0.16-1.01, P = 0.008] and overall survival (HR = 0.43, 95% CI 0.15-1.23, P = 0.040) compared with patients with high PD-L1 expression.In this translational study, we showed, for the first time, the prognostic value of PD-L1 expression in TGCTs and our data imply that the PD-1/PD-L1 pathway could be a novel therapeutic target in TGCTs.© The Author 2015. Published by Oxford University Press on behalf of the European Society for Medical Oncology. All rights reserved. For permissions, please email: journals.permissions@oup.com.

Immune checkpoint blockade (ICB) is considered as a promising approach for cancer treatment. However, the potency of ICB therapy in yolk sac tumors (YSTs) has not been confirmed, and the comprehensive analysis of tumor immune microenvironment and the expression of PD-1/PD-L1 and CTLA4 were also not thoroughly evaluated.Immunohistochemistry was performed in formalin-fixed, paraffin-embedded tumor specimens from 23 YSTs patients to detect the density and distribution of tumor-infiltrating T cells, tertiary lymphoid structures (TLSs), as well as the expression of PD-1/PD-L1 and CTLA4.Overall, more than half (61 %) of all patients exhibited an immune-desert phenotype based on CD3 T cells. PD-1 expression was identified in five tumor samples (21.7 %), and PD-L1 expression exhibited a different positive rate in tumor cells (TCs) and tumor-infiltrating lymphocytes (TILs) (39.1 % and 17.4 %). Noteworthily, the rate of positive CTLA4 expression in both TCs and TILs was markedly higher (69.6 % and 56.5 %) than those of PD-1 and PD-L1 expression. Furthermore, TLSs were observed in 21.74 % of all tissues, and samples with TLSs exhibited significantly higher densities of TILs and higher expression of immune checkpoint molecules, particularly PD-1/PD-L1. In addition, tumors located in testes also exhibited a higher density of TILs and higher expression of immune checkpoint molecules.Generally a high frequency of CTLA4 expression was found, PD-1/PD-L1 expression, the immune-inflamed phenotype, and TLSs were low frequency in YSTs, however, YSTs in testes showed a higher density of TILs and higher expression of immune checkpoint molecules.Copyright © 2023. Published by Elsevier Inc.

Although both seminomatous and nonseminomatous testicular germ cell tumors (TGCTs) have favorable outcomes with chemotherapy, a subset is chemorefractory, and novel therapeutic options are needed.To molecularly characterize chemotherapy-refractory TGCTs.Archival tissues from 107 chemotherapy-treated and relapsed TGCT patients (23 seminomas; 84 nonseminomas) underwent hybrid-capture-based genomic profiling to evaluate four classes of genomic alterations (GAs). Tumor mutational burden (TMB) and microsatellite instability (MSI) were also measured.Genomic profiling on tumor samples from chemotherapy-refractory TGCTs.Descriptive analyses and differences between seminoma and nonseminoma subgroups were reported.The mean GA/tumor was 2.9 for seminomas and 4.0 for nonseminomas (p=0.04). KRAS alterations (mainly amplifications) were the most common GAs at the single-gene level (47.8% of seminomas and 51.2% of nonseminomas). RAS-RAF pathway (56.5% vs 52.3%) and cell-cycle pathway (52.2% vs 56.0%) were the most common GA classes in seminomas and nonseminomas, respectively. Receptor tyrosine kinase pathway and PI3K pathway GAs were more frequent in seminomas (p=0.02). Median TMB was 1.8 mutations/Mb for seminomas and 2.7 mutations/Mb for nonseminomas (p=0.098), and MSI-high status was found in one nonseminoma only (1.2%). A lack of clinical outcome correlation is a limitation of the present analyses.In chemotherapy-refractory TGCTs, trials with agents targeting the KRAS pathway may be pursued due to the high frequency of KRAS GAs. Overall, the GAs found in refractory seminomas and nonseminomas differ significantly. Considering the frequency of high TMB or MSI-high status, immunotherapy may benefit a small subset of nonseminomas.Testicular cancers that are resistant to or relapse after standard chemotherapy may harbor genomic alterations that are potentially druggable, particularly in the clinical trial setting, and genomic profiling can guide clinical research and disclose therapeutic opportunities for these patients.Copyright © 2018 European Association of Urology. Published by Elsevier B.V. All rights reserved.

Yolk sac tumors (YSTs) are a major histological subtype of malignant ovarian germ cell tumors with a relatively poor prognosis. The molecular basis of this disease has not been thoroughly characterized at the genomic level. Here we perform whole-exome and RNA sequencing on 41 clinical tumor samples from 30 YST patients, with distinct responses to cisplatin-based chemotherapy. We show that microsatellite instability status and mutational signatures are informative of chemoresistance. We identify somatic driver candidates, including significantly mutated genes KRAS and KIT and copy-number alteration drivers, including deleted ARID1A and PARK2, and amplified ZNF217, CDKN1B, and KRAS. YSTs have very infrequent TP53 mutations, whereas the tumors from patients with abnormal gonadal development contain both KRAS and TP53 mutations. We further reveal a role of OVOL2 overexpression in YST resistance to cisplatin. This study lays a critical foundation for understanding key molecular aberrations in YSTs and developing related therapeutic strategies.

Anti-Programed Death 1 (PD-1) is standard immunotherapy for multiple cancers, and the expression of one of its ligands, PD-L1, has been described in germ cell tumors (GCT). Neither the clinical activity of anti-PD-1 nor the incidence of an immunoresponsive tumor microenvironment has been described for GCTs. A patient initially diagnosed with melanoma via fine needle aspiration was treated with one dose of antibody to PD-1. A core needle biopsy was subsequently performed to acquire sufficient tissue for molecular analysis, which led to a change in diagnosis to metastatic embryonal carcinoma. The testicular GCT cohort of The Cancer Genome Atlas was analyzed using a T-cell gene signature associated with benefit from immunotherapy. Primary tumors (N = 134) were categorized as high (T-cell-inflamed), medium, or low (non-T-cell-inflamed) by their T-cell signature derived from RNAseq data. Anti-PD-1 induced decreases in serum markers and a 33% reduction in tumor volume. Gene expression revealed a T-cell-inflamed tumor microenvironment in 47% of testicular GCTs, including seminoma (83%) and nonseminoma (17%) tumor subtypes. Expression of alpha-fetoprotein (AFP) RNA correlated with lack of the T-cell signature, with increasing AFP RNA inversely correlating with the inflamed signature and expression of IFNγ-associated genes. These data suggest that GCTs can respond to anti-PD-1 and that gene expression profiling supports investigation of immunotherapy for treatment of GCTs. Cancer Immunol Res; 4(11); 903-9. ©2016 AACR.©2016 American Association for Cancer Research.

Testicular germ cell tumours (GCTs) are the only universally curable solid malignancy. The long-term cure rate of >95% is attributed to the extraordinary sensitivity to cisplatin-based treatment but a proportion of patients die due to a progression of the chemotherapy-refractory disease. While treatment of a variety of solid cancers was significantly improved with recent immune therapies, the immunology and immunotherapy remained underinvestigated in GCTs.In this narrative review, we summarize evidence about immune-related mechanisms and possible immune therapies in GCTs and provide insights and implications for future research and clinical practice.We performed a comprehensive search of PubMed/MEDLINE to identify original and review articles reporting on immune mechanisms and immunotherapy in GCTs. Review articles were further searched for additional original articles.Clear link of immune surveillance and the presence of GCT have been identified with several novel immune-related prognostic biomarkers published recently. Several case reports, case series, and preliminary results from phase I-II studies are emerging to report on the efficacy of immune checkpoint inhibitors.Newly discovered immune biomarkers provide an evidence supporting the role of immune environment in the GCT biology. While these discoveries provide only an initial insight into the immunobiology, strong correlation with prognosis is evident. This provided a premise to investigate the treatment efficacy of novel immunotherapy. Some efficacy of these treatments has been reported in clinical setting; however, the results of published studies with immune checkpoint inhibitor monotherapy seem to be disappointing.Immune-related mechanisms and efficacy of immune checkpoint blockade in GCTs should be further investigated in preclinical and clinical studies.© 2019 American Society of Andrology and European Academy of Andrology.

We studied 137 primary testicular germ cell tumors (TGCTs) using high-dimensional assays of genomic, epigenomic, transcriptomic, and proteomic features. These tumors exhibited high aneuploidy and a paucity of somatic mutations. Somatic mutation of only three genes achieved significance-KIT, KRAS, and NRAS-exclusively in samples with seminoma components. Integrated analyses identified distinct molecular patterns that characterized the major recognized histologic subtypes of TGCT: seminoma, embryonal carcinoma, yolk sac tumor, and teratoma. Striking differences in global DNA methylation and microRNA expression between histology subtypes highlight a likely role of epigenomic processes in determining histologic fates in TGCTs. We also identified a subset of pure seminomas defined by KIT mutations, increased immune infiltration, globally demethylated DNA, and decreased KRAS copy number. We report potential biomarkers for risk stratification, such as miRNA specifically expressed in teratoma, and others with molecular diagnostic potential, such as CpH (CpA/CpC/CpT) methylation identifying embryonal carcinomas.Copyright © 2018 The Author(s). Published by Elsevier Inc. All rights reserved.

Testicular germ cell tumors (TGCTs) are nearly universally curable malignancies. Nevertheless, standard cisplatin-based chemotherapy is not curative in a small subgroup of patients. Previously, we showed that PD-L1 overexpression is associated with worse prognosis in TGCTs, while tumor infiltrating lymphocytes (TILs) are prognostic in different types of cancer. This study aimed to evaluate the prognostic value of PD-1 and PD-L1 expressing TILs in TGCTs.PD-L1 positive TILs were found significantly more often in seminomas (95.9% of patients) and embryonal carcinomas (91.0%) compared to yolk sac tumors (60.0%), choriocarcinomas (54.5%) or teratomas (35.7%) (All p < 0.05). TGCTs patients with high infiltration of PD-L1 positive TILs (HS ≥ 160) had significantly better progression-free survival (HR = 0.17, 95% CI 0.09 - 0.31, p = 0.0006) and overall survival (HR = 0.08, 95% CI 0.04 - 0.16, p = 0.001) opposite to patients with lower expression of PD-L1 (HS < 150). PD-1 expressing TILs were not prognostic in TGCTs.Surgical specimens from 240 patients with primary TGCTs were included into this translational study. The PD-1 and PD-L1 expression on tumor and TILs were detected by immunohistochemistry using anti-PD-1 and anti-PD-L1 monoclonal antibody. Scoring was performed semiquantitatively by weighted histoscore (HS) method.The prognostic value of PD-L1 expressing TILs in TGCTs was demonstrated for the first time.

Treatment options for patients with platinum refractory metastatic germ cell tumours (GCT) relapsing after high-dose chemotherapy and autologous stem cell transplantation are limited and survival is poor. Antibodies directed against programmed cell death protein-1 (PD-1) and programmed cell death ligand-1 (PD-L1) are currently assessed within clinical trials. We present updated data on our experience with checkpoint inhibitors as a compassionate use off-label treatment attempt for highly-pretreated patients with GCT and provide an overview of the current literature on PD-L1 expression in this rare tumour entity.We analysed all patients with platinum refractory GCT treated with checkpoint inhibitors at our institutions between 2015 and 2017. Data were retrieved retrospectively from the patient charts.Seven patients were treated with nivolumab or pembrolizumab. Four patients received single-dose treatment and died shortly afterwards due to tumour progression; the remaining three patients received treatment for at least 6 months. No significant treatment toxicity was observed. Long-term tumour response was achieved in two of the three patients, both of them highly positive for PD-L1 staining.We consider checkpoint inhibition to be efficient in carefully selected patients with platinum refractory GCT. However, predictive markers associated with tumour response are not yet known and larger prospective clinical trials are warranted.Copyright © 2017 Elsevier Ltd. All rights reserved.

The outcome for patients with recurrent and metastatic germ cell tumors can be dismal, and novel salvage therapies are required for these patients. Here we describe a case of metastatic germ cell tumor in which 30% of cells were positive for PD-L1. This tumor achieved a durable response to toripalimab, a monoclonal anti-PD-1 antibody. Follow-up for 36 months post-treatment confirmed no disease progression. Continuous remission was maintained even when treatment was interrupted after 18 months because of an immune-related adverse event (allergic rhinitis). Thus, toripalimab may be an alternative choice for salvage therapy in patients with recurrent and metastatic germ cell tumors.

Despite remarkable results with salvage standard-dose or high-dose chemotherapy ∼15% of patients with relapsed germ-cell tumors (GCT) are incurable. Immune checkpoint inhibitors have produced significant remission in multiple tumor types. We report the first study of immunotherapy in patients with GCT.Single arm phase II trial investigating pembrolizumab 200 mg i.v. Q3weeks until disease progression in patients with relapsed GCT and no curable options. Patients age ≥18 with GCT who progressed after first-line cisplatin-based chemotherapy and after at least one salvage regimen (high-dose or standard-dose chemotherapy) were eligible. Centrally assessed programmed death-ligand 1 (PD-L1) on tumor and infiltrating immune cells was scored. Primary end point was overall response rate using immune-related response criteria. Simon two-stage design with type I error 20% and power 80% was utilized.Twelve male patients were enrolled. Median age was 38 years. All patients had nonseminoma. Primary site was testis (11) or mediastinum (1). Median AFP 615 (range 1-32, 760) and hCG 4 (range 0.6-37, 096). Six patients had late relapse (>2 years). Median number of previous chemotherapy regimens was 3. Six patients received prior high-dose chemotherapy. Two patients had positive PD-L1 staining (H-score 90 and 170). Median number of pembrolizumab doses was 2 (range 1-8). There were six grade 3 adverse events. No immune-related adverse events were reported. No partial or complete responses were observed. Two patients achieved radiographic stable disease for 28 and 19 weeks, respectively; both had continued rising AFP level despite radiographic stability and had negative PD-L1 staining.This is the first reported trial evaluating immune checkpoint inhibitors in GCT. Pembrolizumab is well tolerated but does not appear to have clinically meaningful single-agent activity in refractory GCT.NCT02499952.© The Author 2017. Published by Oxford University Press on behalf of the European Society for Medical Oncology. All rights reserved. For permissions, please email: journals.permissions@oup.com.