Circulating MicroRNAs, the Next-Generation Serum Biomarkers in Testicular Germ Cell Tumours: A Systematic Review

Oncologic outcomes of retroperitoneal lymph node dissection following first-line chemotherapy for metastatic non-seminomatous germ-cell tumors

BACKGROUND

Post-chemotherapy retroperitoneal lymph node dissection (pcRPLND) is integral to multimodal treatment of patients with metastatic non-seminomatous germ-cell tumors (NSGCT). We review pathologic and long-term outcomes of pcRPLND following first-line chemotherapy with a focus on residual mass size and primary tumor histology. Our goal was to identify new predictive approaches that can refine surgical indications.

PATIENTS AND METHODS

Patients who underwent pcRPLND for NSGCT at our institution between 1 January 2000 and 18 January 2023 following first-line chemotherapy were included. The primary outcome was surgical pathology categorized as (i) viable non-teratomatous germ-cell tumor (GCT) (with or without teratoma), (ii) teratoma only, or (iii) fibrosis/necrosis stratified by largest residual mass size. Secondary outcomes included 10-year relapse-free survival, disease-specific survival, and overall survival.

RESULTS

Of 1027 eligible patients, 45% had teratoma and 4% had viable non-teratomatous GCT found at pcRPLND. With a median follow-up of 5.2 years, there was one isolated retroperitoneal relapse and 26 GCT-related deaths. As the residual mass size increased, the likelihood of teratoma in the pcRPLND specimen increased from ∼20% (residual masses <1 cm) to ∼70% (>5 cm). The risk of viable non-teratomatous GCT similarly increased from ∼2% up to ∼10%. Ten-year relapse-free and overall survival worsened with increasing mass size. Adjusting for risk group, clinical stage, residual mass size, and lymphovascular invasion at orchiectomy, the presence of yolk sac tumor [odds ratio (OR) 1.86, 95% confidence interval (CI) 1.35-2.56] and teratoma in the orchiectomy specimen (OR 3.09, 95% CI 2.27-4.23) were each independently associated with finding teratoma or viable non-teratomatous GCT at pcRPLND.

CONCLUSIONS

Following first-line chemotherapy, pcRPLND provides effective control of the retroperitoneum with few relapses and GCT-related deaths. Guideline recommendations for or against pcRPLND based on residual mass size alone should be revisited due to the significant association of orchiectomy histology with pcRPLND pathology and the benefits surgical consolidation has on disease control and survival.

MicroRNA-371-373 cluster and methylome analysis suggests that a subset of 'somatic-type' malignancies arising in germ cell tumors may originate in yolk sac tumor components

Somatic-type malignancies (SMs) arising in germ cell tumors (GCTs) are aggressive neoplasms resistant to systemic treatment. Most are diagnosed in metastatic sites after chemotherapy; however, they have also been well-documented in primary testicular GCTs. Historically, SMs were thought to originate in components of teratoma that acquire molecular alterations equivalent to those that characterize their true somatic counterparts. However, recent studies have shown that SMs typically lack the hallmark molecular alterations seen in similar somatic tumors. Additionally, clinicopathologic and molecular data suggest that a subset may derive from yolk sac tumor (YST) rather than teratoma. In this study, we evaluated the relationship between conventional histological types of GCTs and SMs by comparing expression of microRNA (miR)-371-373 and genomic methylation profiles. A total of 96 samples (including multiple paired conventional GCT-SM samples from individual tumors) were assessed for miR-371-373 expression by RT-qPCR and genomic DNA methylation using a clinically validated assay. Expression of miR-371-373 was higher in conventional GCTs than in SMs (considered as a single category encompassing all histological subtypes). However, miR-371-373 expression was heterogeneous among SMs, with significantly higher levels in sarcomatoid YST (SYST) and glandular neoplasms than in other SMs. Genomic DNA methylation analysis showed that SMs (considered as a single category) did not form a distinct cluster. Instead, they grouped into multiple clusters that did not show perfect correspondence with histology and often included conventional GCTs. Genome-wide methylation assessment showed a higher abundance of hypermethylated regions in SMs than in conventional GCTs. Analysis of paired conventional GCT and 'somatic-type' components that did not meet size criteria for SMs dissected from individual tumors demonstrated separation according to histology, suggesting that epigenetic processes play a role in the transition from conventional GCT to 'somatic-type' phenotypes. Gene-level and pathway-level analyses identified MAPK/RAS signaling, mitosis/proliferation, differentiation towards neural tissue/neuroectoderm, epithelial-to-mesenchymal transition, and DNA repair as key differentially regulated processes in components with somatic-type histology, suggesting mechanisms of progression from conventional to 'somatic' phenotypes in GCT. These results support the hypothesis that a subset of SMs derive from YST and suggest that some subtypes (such as SYST) may represent 'intermediate' phenotypes. Additionally, analysis of differentially methylated promoter regions in SM identified genes and biologic processess that may underlie 'somatic tranformation' in GCTs. © 2025 The Author(s). The Journal of Pathology published by John Wiley & Sons Ltd on behalf of The Pathological Society of Great Britain and Ireland.

MicroRNA-371-373 cluster extracellular vesicle-based communication in testicular germ cell tumors

Testicular germ cell tumors (TGCTs) represent the most common type of cancer in young adults. The cluster of microRNAs 371-373 is highly upregulated in TGCTs, and detection of miR-371a-3p specifically is currently being developed for clinical implementation as a sensitive and specific biomarker for TGCT, except for teratoma. Extracellular vesicles (EVs) are nano-sized particles used for cell communication, being increasingly regarded as potential sources of cancer biomarkers. Thus, the aim of this study was to characterize EVs from a wide range of TGCT samples, including cell lines, tissue explants and matched plasma samples from patients and healthy donors, and then use these samples to assess microRNA expression (miR-371-373 cluster and let-7e). TGCT-derived EVs were successfully isolated and characterized according to MISEV guidelines. TGCT cell lines showed different levels of EV-derived miR-371-373 cluster and let-7e. Upon differentiation of NT2 cells with ATRA, both cellular and EV-derived miR-371-373 cluster were downregulated, whereas let-7e was upregulated. TGCT patient samples presented high levels of EV-derived miR-371-373, except for the teratoma samples. We conclude that a significant portion of the circulating miR-371-373 cluster used as a TGCT biomarker in the clinic is secreted into EVs, and that this cluster and the let-7 family of microRNAs may be related with TGCT intercellular communication and differentiation.

Mediastinal NUT Carcinoma With Raised Serum Alpha-Fetoprotein Mimicking a Malignant Germ Cell Tumor: Suspicion Raised Due to Negative Serum miR-371a-3p Levels

NUT carcinoma is challenging to diagnose and may mimic a germ cell tumor (GCT) due to raised serum alpha-fetoprotein (AFP). A 15-year-old patient presented with back pain and cough. Investigation revealed a mediastinal mass and multiple bone metastases. Serum AFP was highly elevated, consistent with a metastatic malignant nonseminomatous GCT. Aggressive chemotherapy was initiated with initial response, unfortunately not sustained. Diagnostic biopsy showed undifferentiated tumor cells with weak GCT immunophenotype but was ultimately non-diagnostic. Serum miR-371a-3p levels, highly sensitive/specific for malignant GCTs, were negative casting diagnostic suspicion. Routine use of agnostic molecular investigations, including whole genome sequencing, identified a chromosome 15:19 translocation, with BRD4::NUTM1 gene fusion on RNA sequencing, confirming NUT carcinoma. Subsequent NUTM1 immunohistochemistry was positive. A high index of clinical suspicion is required for non-pathologically/molecularly confirmed diagnoses. Serum miR-371a-3p quantification ruled out malignant GCT and routine agnostic molecular studies identified the correct diagnosis; a low threshold for NUTM1 immunohistochemistry is thus recommended.

Current Role of MicroRNAs in the Diagnosis and Clinical Management of Germ Cell Tumors

Germ cell tumors (GCTs) are a rare and heterogeneous group of neoplasms arising from primitive germ cells. MicroRNAs are small noncoding RNAs that have emerged as potential cancer biomarkers in the last decade. In particular, miR-371a-3p has shown good diagnostic performance for germ cell neoplasia in situ-derived testicular GCTs in several well-established cohorts and is expected to enter the clinical arena in the near future. GCTs universally exhibit high expression of miR-371-373 and miR-302/367 clusters and low expression of let-7 family miRNAs. Further studies are needed to assess the potential role of these miRNAs as biomarkers of ovarian and extragonadal GCTs.

Tissue-Based Biomarkers Important for Prognostication and Management of Genitourinary Tumors, Including Surrogate Markers of Genomic Alterations

A better understanding of the molecular alterations that underlie urologic malignancies and advances in targeted therapies has impacted classification, prognostication, and treatment. In bladder tumors, these advances include the development of antibody-drug conjugates targeting nectin-4 and Trop-2, as well as human epidermal growth factor receptor 2 and immunotherapy. In prostate cancer, assessment of the percentage of Gleason pattern 4, presence of cribriform glands, and molecular alterations, including PTEN and mismatch repair protein loss, have become standard for clinical care. In renal malignancies, alterations in TSC1/2, mammalian target of rapamycin, anaplastic lymphoma kinase, and other genes impact classification and therapeutic decisions.

Potential next generation markers of testicular germ cell tumors: miRNA-371a-3p

BACKGROUND

Testicular germ cell tumors (TGCTs) account for approximately 98% of all testicular cancers, predominantly affecting young to middle-aged men. Early diagnosis and treatment result in a cure rate of over 95%. However, conventional serum tumor markers (STMs) such as alpha-fetoprotein (AFP), β-human chorionic gonadotropin (β-hCG), and lactate dehydrogenase (LDH), which are recommended by NCCN and EAU guidelines, have limited sensitivity, often below 60%, which diminishes their clinical utility. Recently, miRNA-371a-3p, an embryonic stem cell-associated microRNA, has been identified as being specifically expressed in TGCTs. This microRNA can be reliably detected in peripheral blood and fulfills all seven Lange-Winfield criterias for tumor markers. Notably, miRNA-371a-3p has demonstrated superior diagnostic, therapeutic, and follow-up capabilities compared to conventional STMs in TGCTs. Its potential to replace conventional STMs in clinical practice is already recognized in several clinical guidelines.

METHODS

A PubMed search using subject headings and free-text terms related to MicroRNA-371a-3p in TGCT management was conducted. Relevant references were also tracked, and key studies were reviewed based on predefined exclusion criteria.

RESULTS

Out of 368 identified studies, 67 met inclusion criteria. These studies focused on MicroRNA-371a-3p's discovery, detection methods, diagnostic utility in TGCTs, and cost-effectiveness. First identified over a decade ago, microRNA-371a-3p is now established as a highly specific blood-based marker for TGCTs, valuable for diagnosis, monitoring, and follow-up, and more cost-effective than conventional STMs.

CONCLUSIONS

MicroRNA-371a-3p is a promising, highly sensitive marker for TGCTs, offering better performance and cost efficiency than conventional STMs, likely to become the next-generation diagnostic tool for TGCTs.

Management of Small Testicular Masses: A Delphi Consensus Study

BACKGROUND AND OBJECTIVE

The majority of small testicular masses (STMs) are benign and therefore radical orchidectomy (RO) may represent overtreatment. In appropriately selected patients, surveillance or testis-sparing surgery (TSS) is an alternative option to preserve testicular function. Since there are no clear guidelines, we aimed to develop consensus recommendations on the management of STMs.

METHODS

A four-round Delphi study was conducted by 24 experts representing multiple subspecialties to reach consensus. Consensus was defined as ≥75% of the participants scoring within the same 3-point grouping (1-3, disagree; 4-6, uncertain; 7-9, agree.). The first two rounds were survey based, the third round was an online meeting to discuss uncertainties from the first two rounds, and the fourth round was a review of the final consensus statements from rounds 1-3.

KEY FINDINGS AND LIMITATIONS

The initial survey consisted of 126 statements. Following the four rounds of assessment, a list of 96 statements were produced, which focused on clinical and biochemical assessment, colour Doppler ultrasound (CDUS) characteristics, and management options including surveillance, RO, and TSS. Management should be personalised according to risk factors for testicular cancer, fertility status, uni- or bilateral tumours, status of the contralateral testis, and CDUS characteristics, with solid lesions displaying vascularity and hypoechogenicity being more suspicious for malignancy. The consensus statements are prone to a bias, and some may not reflect robust, randomised evidence.

CONCLUSIONS AND CLINICAL IMPLICATIONS

The expert panel has produced consensus recommendations on the management of STMs, and TSS should be considered in patients with an STM. The recommendations could aid in the dissemination of best practice.

PATIENT SUMMARY

There are no clear guidelines on the management of small testicular masses. Excising the whole testicle (radical orchidectomy) with a small or an indeterminate mass may affect fertility and hormonal function. A panel of experts was formed, and consensus recommendations were developed on how to deal with small and indeterminate testicular masses, which include surveillance or testis-sparing surgery.

Potentialities and critical issues of liquid biopsy in clinical practice: An umbrella review

BACKGROUND

Liquid biopsy (LB) is a laboratory test performed on a fluid sample aiming at analyzing molecular data derived from circulating cells and related entities, or from nucleic acids. This umbrella review aims to map and evaluate the evidence supporting the use of LB in medicine across different medical specialities and conditions.

METHODS

We searched three repositories from database inception up to October 1, 2023 and we included meta-analyses of observational studies reporting data on the use of LB, compared to gold standard, and its accuracy (area under the curve, AUC).

RESULTS

Among 726 articles initially screened, 42 systematic reviews were included. Most of the outcomes explored (202/211) were related to cancer. We found that 75/211 had an excellent accuracy (AUC >0.90), with one comparison with an AUC equal to 1, i.e., Cell-Free Human Papillomavirus DNA (cfHPV-DNA) for HPV-positive oropharyngeal squamous cell carcinoma. However, considering published meta-analyses, all the outcomes were graded as very low on the GRADE criteria, and the heterogeneity was never reported.

DISCUSSION

The literature about LB is rapidly increasing and some promising data about precision oncology are now available. However, this umbrella review on existing meta-analyses highlighted some critical issues for providing quantitative estimations on the different roles of LB.

Biomarker microRNA-371a-3p - expression in malignancies other than germ-cell tumours

PURPOSE

microRNA-371a-3p (M371) is considered a highly sensitive and specific serum biomarker of testicular germ cell tumours (GCTs). However, little is known about the expression of M371 in nontesticular malignancies (NTMs), so far. As knowledge about the expression of the marker in other malignancies is a prerequisite for the clinical application of the test we aimed to explore the M371 expression in other cancers.

METHODS

M371 serum levels were measured in 137 patients with NTM of 12 different neoplastic entities using the IVDR-certified M371-Test for quantitative real-time PCR. Median M371 serum levels and percentages of M371 level elevations were calculated for the entire NTM group and for entity-specific subgroups. The results were compared with GCT patients (n = 20) and with tumour-free male controls (n = 20) using descriptive statistical methods.

RESULTS

Eight patients with NTMs had M371 serum level elevations, corresponding to a false-positive rate (FPR) of 5.84% (95% confidence intervals (CIs) 2.55-11.18%). Expression rates in GCTs and controls were 100% and zero, respectively. Thus, the specificity of the M371-Test for GCT is 94.90% (95% CI 90.21-97.77%) when all NTMs and tumour-free controls are considered. Remarkably, three out of 5 patients with multiple myeloma had elevated M371 levels.

CONCLUSION

The false-positive rate of the M371-Test in other malignancies than GCT is very low, and almost identical with that in healthy males, corresponding to a high specificity of 94.9% for detection of GCT. The surprising finding of M371 elevations in patients with multiple myeloma needs further investigation.

Global burden and trends of testicular cancer in adolescents and young adults from 1990 to 2021, with predictions to 2035

Testicular cancer predominantly affects adolescents and young adults (AYAs) aged 15-39 years. This study analyzed the global, regional, and national burden of testicular cancer among AYAs (1990 to 2021). Data from the Global Burden of Disease study was used to calculate age-standardized rates of incidence (ASIR), prevalence (ASPR), and disability-adjusted life years (ASDR). Trends were assessed using the Joinpoint regression and Bayesian age-period-cohort models, with projections up to 2035. Results showed the global ASIR of 4.05 (95% CI: 3.80-4.35), ASPR of 31.05 (95% CI: 28.88-33.68), and ASDR of 24.82 (95% CI: 22.99-26.91) per 100,000 in 2021, respectively. From 1990 to 2021, ASIR and ASPR increased, while ASDR remained relatively stable. Significant geographical disparities were observed, with Europe and Latin America showing higher burdens compared to Asia and Africa. The 25-29 age group had the highest age-specific rate of incidence (5.58; 95% UI: 5.25-5.97) and disability-adjusted life years (34.09; 95% UI: 31.55-37.11) per 100,000, while the 30-34 age group had the highest age-specific prevalence rate (43.12; 95% UI: 40.51-46.56) per 100,000 in 2021. By 2035, the global numbers of incidence and prevalence cases were projected to increase, with DALYs and age-standardized rates declining. These findings are crucial for informing global strategies in testicular cancer prevention.

Non-Invasive miRNA Profiling for Differential Diagnosis and Prognostic Stratification of Testicular Germ Cell Tumors

BACKGROUND/OBJECTIVES

Testicular germ cell tumors (TGCT) are common in young adult men and have high cure rates. Conventional serum tumor markers and imaging are not able to differentiate between histologic subtypes of the disease, which portend different prognoses and require distinct therapeutic strategies. Micro-RNAs (miRNAs) are small non-coding transcripts involved in the post-transcriptional regulation of gene expression, which have emerged as promising biomarkers in a variety of tumors. This study aimed to assess the potential of differentially expressed miRNAs in differential diagnosis and prognostication among TGCT patients with various histologic subtypes.

METHODS

Transcriptomic analysis of 134 patients from The Cancer Genome Atlas (TCGA)-TGCT database was conducted. miRNA differential expression analysis among seminomatous, embryonal carcinoma, mixed GCT, and teratoma was performed, followed by ROC curve analysis of the most significantly up- and downregulated miRNAs, respectively. Statistical associations of miRNA expression with AJCC stage were also investigated along with miRNA target network analysis and evaluation of miRNA detection in patients' fluids.

RESULTS

Upregulation of seven miRNAs (hsa-mir-135a-1, hsa-mir-135a-2, hsa-mir-200a, hsa-mir-200b, hsa-mir-203b, hsa-mir-375, hsa-mir-582) and downregulation of seven additional miRNAs (hsa-mir-105-1, hsa-mir-105-2, hsa-mir-4433a, hsa-mir-548x, hsa-mir-5708, hsa-mir-6715a, hsa-mir-767) were identified. miRNAs displayed a high sensitivity/specificity of 0.94/1.0 (AUC = 0.98) for the upregulated and 0.97/0.94 (AUC = 0.96) for the downregulated signature. Deregulated expression of these miRNAs was significantly associated with AJCC stage and distant organ metastasis (p < 0.001), overall supporting their prognostic strength. Both signatures were detectable in body fluids, particularly urine. miRNA target network analysis supported the functional role of these miRNAs in the regulation of cancer-related processes such as cell proliferation via deregulation of pivotal oncogenes.

CONCLUSIONS

These findings support the clinical value of two novel miRNA signatures in differential diagnosis and prognostic stratification of various histologic subtypes of TGCT, with potential treatment implications.

The New Tumour Biomarker miRNA-371-3p Influences Cisplatin Sensitivity of Testicular Germ Cell Tumour Cell Lines

Cisplatin is used to treat a variety of malignancies, including testicular germ cell tumours (TGCTs). Although cisplatin-based chemotherapy yields high response rates, a subset of patients develop cisplatin resistance, limiting treatment options and worsening prognosis. Therefore, there is a high clinical need for new therapeutic strategies targeting cisplatin-resistant TGCTs. MicroRNA-371a-3p (miR-371), the new serum biomarker for TGCTs, shows significantly increased expression in cisplatin-resistant TGCT cell lines compared to sensitive parental cell lines. However, the functional impact of miR-371 on cisplatin sensitivity has not been investigated yet. To evaluate the impact of miR-371 on cisplatin sensitivity, antagomirs were used to inhibit miR-371 expression, resulting in a > 98% decrease in miR-371 expression. Cisplatin sensitivity was significantly increased after miR-371 inhibition in cisplatin-resistant and corresponding parental TGCT cell lines, indicating a strongly reduced viability and increased apoptosis after cisplatin treatment in miR-371-inhibited cells. Our results suggest that miR-371 may contribute to the development of cisplatin resistance in TGCTs. Interfering with miR-371 expression can increase the cisplatin sensitivity of tumour cells, which may represent a promising approach to improve future therapeutic outcomes in patients with TGCTs, especially those with cisplatin-resistant disease.

French AFU Cancer Committee Guidelines - Update 2024-2026: Testicular germ cell cancer

OBJECTIVE

To update the recommendations for the management of germ cell tumours of the testis.

MATERIALS AND METHODS

Comprehensive PubMed review from 2022 on the diagnosis, treatment and follow-up of testicular germ cell tumours (TGT), as well as safety of treatments. The level of evidence of the studies was assessed.

RESULTS

The initial assessment of a patient with a germ cell tumour of the testis is based on a clinical examination, biological evaluation (by measuring the serum markers AFP, total hCG, and LDH) and radiological evaluation (scrotal ultrasound and thoraco-abdomino-pelvic computed tomography [TAP]). Inguinal orchiectomy is the first therapeutic step, as it allows histological diagnosis and defines the local stage and risk factors for progression in stage I nonseminomatous germ cell tumours (NSGCTs). For patients with pure stage I seminoma, the risk of progression is between 15 and 20%, so surveillance is preferred in compliant patients; adjuvant chemotherapy with carboplatin AUC 7 is an option; and the indications for lumbo-aortic radiotherapy are limited. For patients with stage I NSGCT, various options exist, namely, surveillance or a risk-adapted strategy (surveillance or 1 cycle of bleomycin etoposide cisplatin [BEP] depending on the presence or absence of vascular emboli within the tumour). Retroperitoneal lymph node dissection for staging has a very limited role. Treatment of metastatic GCT consists of chemotherapy with BEP in the absence of contraindication to bleomycin, the number of cycles of which is defined according to the prognostic groups of the International Germ Cell Cancer Consortium Group (IGCCCG). Lumbo-aortic radiotherapy is still the standard treatment for stage IIA seminomatous germ cell tumours (SGCTs). At the end of chemotherapy, the size of any residual mass should be assessed via a TAP scan for SNGCTs, with retroperitoneal lymph node dissection recommended for any residual mass greater than 1cm, along with removal of all other metastatic sites. For SGCT, reassessment via 18FDG PET scans is necessary to determine the surgical indication for residual masses>3cm. Surgery remains rare in these situations.

CONCLUSION

Adherence to the recommendations for the management of GCT results in excellent specific survival rates of 99% for patients with stage I disease and over 85% for patients with metastatic disease.

Long-term Relapse and Survival in Clinical Stage I Testicular Teratoma

BACKGROUND AND OBJECTIVE

Studies in metastatic nonseminomatous germ-cell tumor (NSGCT) suggest that the presence of teratomatous elements in the primary tumor is a risk factor for poor survival. Many guidelines have extrapolated this observation and recommend adjuvant retroperitoneal lymph-node dissection (RPLND) even for clinical stage I (CSI) teratoma confined to the testicle. Our objective was to assess relapse-free survival (RFS), cancer-specific survival (CSS), overall survival (OS) among patients with CSI pure teratoma in comparison to CSI NSGCT.

METHODS

Patients with CSI NSGCT managed with surveillance between 1980 and 2023 were identified in the prospectively maintained Princess Margaret Cancer Centre database. We compared cases with pure teratoma with or without somatic transformation in the primary tumor to all other nonteratomatous NSGCTs.

KEY FINDINGS AND LIMITATIONS

A total of 774 patients with CSI NSGCT were identified, including 63 (8.1%) with pure teratoma and/or somatic transformation in the primary tumor. Median follow-up was 61 mo. The pure teratoma group had superior RFS at 6 yr (85.2% vs 67.9%; p = 0.008). There were no significant differences in 6-yr CSS (100% vs 99.1%; p = 0.92) or OS (97.4% vs 98.1%; p = 0.33). Limitations include the single-center setting and the limited follow-up (median 61 mo), hindering the ability to detect late relapses.

CONCLUSIONS AND CLINICAL IMPLICATIONS

CSI pure teratoma managed with surveillance is associated with a low risk of relapse overall and significantly lower risk of relapse in comparison to other CSI NSGCTs. No patients with CSI teratoma in the study population died of testicular cancer. Guidelines should be revised to include surveillance as a preferred approach for CSI teratoma.

PATIENT SUMMARY

We compared survival rates after testicle removal in clinical stage I testicular cancer for two different tumor types. We found that cancer-specific and overall survival rates were similar for pure teratoma tumors and nonseminoma tumors, and that the recurrence rate was lower for pure teratoma tumors. Our results support surveillance as a suitable option after surgery for patients with clinical stage I testicular teratoma.

First Indicator of Relapse in Testicular Cancer and Implications for Follow-up: Analysis of the Swiss Austrian German Testicular Cancer Cohort Study (SAG TCCS)

Background and objective

Follow-up for patients with testicular cancer should ensure early detection of relapses. Optimal schedules and minimum requirements for cross-sectional imaging are not clearly defined, and guideline recommendations differ. Our aim was to analyse the clinical impact of different imaging modalities for detection of relapse in a large prospective cohort (Swiss Austrian German Testicular Cancer Cohort Study, SAG TCCS).

Methods

Patients with seminoma or nonseminoma were prospectively enrolled between January 2014 and February 2023 after initial treatment (n = 1175). Follow-up according to the study schedule was individualised for histology and disease stage. Only patients who had received primary treatment were considered. We analysed the total number of imaging modalities and scans identifying relapse and the timing of relapse.

Key findings and limitations

We analysed data for 1006 patients (64% seminoma, 36% nonseminoma); 76% had stage I disease. Active surveillance was the most frequent management strategy (65%). Recurrence occurred in 82 patients, corresponding to a 5-yr relapse-free survival rate of 90.1% (95% confidence interval 87.7-92.1%). Median follow-up for patients without relapse was 38.4 mo (interquartile range 21.6-61.0). Cross-sectional imaging of the abdomen was the most important indicator of relapse 57%, abdominal CT accounting for 46% and MRI for 11%. Marker elevation indicated relapse in 24% of cases. Chest X-ray was the least useful modality, indicating relapse in just 2% of cases.

Conclusions and clinical implications

On the basis of findings from our prospective register, we have adapted a follow-up schedules with an emphasis on abdominal imaging and a reduction in chest X-rays. This schedule might provide additional guidance for clinicians and will be prospectively evaluated as SAG TCCS continues to enrol patients.

Patient summary

We analysed the value of different types of imaging scans for detection of relapse of testicular cancer. We used our findings to propose an optimum follow-up schedule for patients with testicular cancer.

Serum Levels of MicroRNA-371a-3p for Predicting the Histology of Postchemotherapy Residual Masses of Germ Cell Tumours

BACKGROUND AND OBJECTIVE

Serum levels of microRNA-371a-3p (M371) represent a novel and sensitive biomarker of germ cell tumours (GCTs). This study analysed the utility of M371 to identify viable cancer (VC) in postchemotherapy (pc) residual masses with the underlying goal of avoiding overtreatment.

METHODS

A multicentric, prospective diagnostic study was conducted in 180 GCT patients undergoing pc resection of residual masses. A correlation of M371 measurement results with the histological presence of VC in masses was found. A receiver operating characteristic analysis was performed for exploring the performance characteristics of the test.

KEY FINDINGS AND LIMITATIONS

The sensitivity was found to be 68.9%, specificity 99.3%, area under the curve 0.813, positive predictive value 0.969, and negative predictive value 0.905; sensitivity is significantly associated with the percentage of VC in the mass. In specimens with ≤10% VC, there were 33.3% elevated M371 levels as opposed to 85.7% in specimens with >50% VC. Teratoma and somatic-type malignancy do not express M371. A lack of a central pathological review is a limitation.

CONCLUSIONS AND CLINICAL IMPLICATIONS

The M371 test can identify 68.9% of patients with VC in pc masses. However, cases with <10% VC in the mass may escape detection. Teratoma does not express M371. The test alone cannot correctly identify patients requiring pc surgery, but it may be a tool for scheduling the extent of surgery.

PATIENT SUMMARY

The microRNA-371a-3p (M371) test can identify about two-thirds of patients with viable cancer in residual metastatic masses following chemotherapy for germ cell tumours. Only masses with high percentages of viable cancer cells can be identified, and the histological subtype teratoma remains undetected with the test.

miR-21, miR-29a, and miR-106b: serum and tissue biomarkers with diagnostic potential in metastatic testicular cancer

The imperative need for sensitive and precise tools is underscored in cancer diagnostics, with biomarkers playing a pivotal role in facilitating early detection and tumor diagnosis. Despite their classical pathological classification, testicular tumors lack valuable markers, emphasizing the necessity to identify and apply serum tumor markers in clinical management. Unfortunately, existing biomarkers exhibit limited sensitivities and specificities. Recent years have witnessed the discovery of novel RNA molecules, presenting a potential breakthrough as diagnostic tools and promising biomarkers. This report presents compelling evidence supporting the detection of early testicular cancer by applying a set of nine microRNAs (miRNAs), establishing them as valuable serum biomarkers for diagnosis. We developed a standardized serum-based measurement protocol and conducted comprehensive statistical analyses on the dataset to underscore the diagnostic accuracy of the miRNA pool. Notably, with a sensitivity exceeding 93%, miR-21, miR-29a, and miR-106b surpass classical serum tumor markers in the context of testicular cancer. Specifically, these miRNAs are poised to enhance clinical decision-making in testicular cancer detection and hold the potential for assessing tumor growth in monitoring chemotherapy outcomes.

A comprehensive overview of liquid biopsy applications in pediatric solid tumors

Liquid biopsies are emerging as an alternative source for pediatric cancer biomarkers with potential applications during all stages of patient care, from diagnosis to long-term follow-up. While developments within this field are reported, these mainly focus on dedicated items such as a specific liquid biopsy matrix, analyte, and/or single tumor type. To the best of our knowledge, a comprehensive overview is lacking. Here, we review the current state of liquid biopsy research for the most common non-central nervous system pediatric solid tumors. These include neuroblastoma, renal tumors, germ cell tumors, osteosarcoma, Ewing sarcoma, rhabdomyosarcoma and other soft tissue sarcomas, and liver tumors. Within this selection, we discuss the most important or recent studies involving liquid biopsy-based biomarkers, anticipated clinical applications, and the current challenges for success. Furthermore, we provide an overview of liquid biopsy-based biomarker publication output for each tumor type based on a comprehensive literature search between 1989 and 2023. Per study identified, we list the relevant liquid biopsy-based biomarkers, matrices (e.g., peripheral blood, bone marrow, or cerebrospinal fluid), analytes (e.g., circulating cell-free and tumor DNA, microRNAs, and circulating tumor cells), methods (e.g., digital droplet PCR and next-generation sequencing), the involved pediatric patient cohort, and proposed applications. As such, we identified 344 unique publications. Taken together, while the liquid biopsy field in pediatric oncology is still behind adult oncology, potentially relevant publications have increased over the last decade. Importantly, steps towards clinical implementation are rapidly gaining ground, notably through validation of liquid biopsy-based biomarkers in pediatric clinical trials.

Initial surveillance in men with marker negative clinical stage IIA non-seminomatous germ cell tumours

OBJECTIVES

To assess whether extended surveillance with repeated computed tomography (CT) scans for patients with clinical stage IIA (CS IIA; <2 cm abdominal node involvement) and negative markers (Mk-) non-seminomatous germ cell tumours (NSGCTs) can identify those with true CS I. To assess the rate of benign lymph nodes, teratoma, and viable cancer in retroperitoneal lymph node dissection (RPLND) histopathology for patients with CS IIA Mk- NSGCT.

PATIENTS AND METHODS

Observational prospective population-based study of patients diagnosed 2008-2019 with CS IIA Mk- NSGCT in the Swedish and Norwegian Testicular Cancer Group (SWENOTECA) registry. Patients were managed with surveillance, with CT scans, and tumour markers every sixth week for a maximum of 18 weeks. Patients with radiological regression were treated as CS I, if progression with chemotherapy, and remaining CS IIA Mk- disease with RPLND. The end-point was the number and percentage of patients down-staged to CS I on surveillance and rate of RPLND histopathology presented as benign, teratoma, or viable cancer.

RESULTS

Overall, 126 patients with CS IIA Mk- NSGCT were included but 41 received therapy upfront. After surveillance for a median (range) of 6 (6-18) weeks, 23/85 (27%) patients were in true CS I and four (5%) progressed. Of the remaining 58 patients with lasting CS IIA Mk- NSGCT, 16 received chemotherapy and 42 underwent RPLND. The RPLND histopathology revealed benign lymph nodes in 11 (26%), teratoma in two (6%), and viable cancer in 29 (70%) patients.

CONCLUSIONS

Surveillance with repeated CT scans can identify patients in true CS I, thus avoiding overtreatment. The RPLND histopathology in patients with CS IIA Mk- NSGCT had a high rate of cancer and a low rate of teratoma.

Prognostic factors for relapse in patients with clinical stage I testicular non-seminoma: A nationwide, population-based cohort study

BACKGROUND

Approximately 30% of patients with clinical stage I non-seminoma (CSI-NS) relapse. Current risk stratification is based on lymphovascular invasion (LVI) alone. The extent to which additional tumor characteristics can improve risk prediction remains unclear.

OBJECTIVE

To determine the most important prognostic factors for relapse in CSI-NS patients.

DESIGN, SETTING, AND PARTICIPANTS

Population-based cohort study including all patients with CSI-NS diagnosed in Denmark between 2013 and 2018 with follow-up until 2022. Patients were identified in the prospective Danish Testicular Cancer database. By linkage to the Danish National Pathology Registry, histological slides from the orchiectomy specimens were retrieved.

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

Histological slides were reviewed blinded to the clinical outcome. Clinical data were obtained from medical records. The association between prespecified potential prognostic factors and relapse was assessed using Cox regression analysis. Model performance was evaluated by discrimination (Harrell's C-index) and calibration.

RESULTS

Of 453 patients included, 139 patients (30.6%) relapsed during a median follow-up of 6.3 years. Tumor invasion into the hilar soft tissue of the testicular hilum, tumor size, LVI and embryonal carcinoma were independent predictors of relapse. The estimated 5-year risk of relapse ranged from < 5% to > 85%, depending on the number of risk factors. After internal model validation, the model had an overall concordance statistic of 0.75. Model calibration was excellent.

CONCLUSION AND RELEVANCE

The identified prognostic factors provide a much more accurate risk stratification than current clinical practice, potentially aiding clinical decision-making.

Predictive and prognostic biomarkers in urological tumours

Advancements in cutting-edge molecular profiling techniques, such as next-generation sequencing and bioinformatic analytic tools, have allowed researchers to examine tumour biology in detail and stratify patients based on factors linked with clinical outcome and response to therapy. This manuscript highlights the most relevant prognostic and predictive biomarkers in kidney, bladder, prostate and testicular cancers with recognised impact in clinical practice. In bladder and prostate cancer, new genetic acquisitions concerning the biology of tumours have modified the therapeutic scenario and led to the approval of target directed therapies, increasing the quality of patient care. Thus, it has become of paramount importance to choose adequate molecular tests, i.e., FGFR screening for urothelial cancer and BRCA1-2 alterations for prostate cancer, to guide the treatment plan for patients. While no tissue or blood-based biomarkers are currently used in routine clinical practice for renal cell carcinoma and testicular cancers, the field is quickly expanding. In kidney tumours, gene expression signatures might be the key to identify patients who will respond better to immunotherapy or anti-angiogenic drugs. In testicular germ cell tumours, the use of microRNA has outperformed conventional serum biomarkers in the diagnosis of primary tumours, prediction of chemoresistance, follow-up monitoring, and relapse prediction.

Multifocality in Testicular Cancer: Clinicopathological Correlations and Prognostic Implications

There are limited data regarding the significance of multifocality in testicular cancer patients. This study evaluated the relationship between multifocality and clinicopathological features determined at the time of radical orchiectomy. The study involved 280 consecutive patients who underwent radical orchiectomy between 2018 and 2023. Multifocality was defined as a distinct tumor focus characterized by a group of malignant cells > 1 mm, clearly differentiated from the primary tumor mass. Uni- and multivariate logistic regression analyses were employed to investigate the association between multifocality and histopathological parameters along with potential risk factors for clinical stages II + III. Multifocality was identified in 44 (15.7%) patients. Significantly smaller primary tumors were observed in subjects with multifocality (20.0 mm vs. 30.0 mm, p = 0.0001), while those exhibiting monofocality presented a markedly elevated rate of tumors exceeding 4 cm (40.3% vs. 18.2%, p = 0.005). Furthermore, multifocality was associated with a significantly higher rate of primary tumors < 2 cm (52.3% vs. 29.2%, p = 0.003). Univariate logistic regression analysis revealed a substantial decrease in the likelihood of multifocality occurrence in seminoma patients with tumors > 4 cm (OR = 0.38, p = 0.017). Meanwhile, in multivariate logistic regression, multifocality did not emerge as a significant risk factor for clinical stages II + III in either seminoma (p = 0.381) or non-seminoma (p = 0.672) cases. Our study suggests that multifocality holds no substantial prognostic relevance for clinically advanced disease in testicular cancer patients. The findings indicate that multifocality is associated with smaller primary tumors, particularly those measuring less than 2 cm.

Detection of Recurrence through microRNA-371a-3p Serum Levels in a Follow-up of Stage I Testicular Germ Cell Tumors in the DRKS-00019223 Study

PURPOSE

Surveillance of clinical stage I (CSI) testicular germ cell tumors (GCT) is hampered by low sensitivity and specificity of current biomarkers for detecting relapses. This study evaluated if serum levels of microRNA371a-3p (M371 test) can: (i) Accurately detect relapses, (ii) detect relapses earlier than conventional technology, and (iii) if elevated postoperative M371 levels may predict relapse.

EXPERIMENTAL DESIGN

In a multicentric setting, 258 patients with testicular CSI GCT were prospectively followed by surveillance for a median time of 18 months with serial measurements of serum M371 levels, in addition to standard diagnostic techniques. Diagnostic characteristics of M371 for detecting relapses were calculated using ROC curve analysis.

RESULTS

Thirty-nine patients recurred (15.1%), all with elevated M371 levels; eight without relapse had elevations, too. The test revealed the following characteristics: area under the ROC curve of 0.993, sensitivity 100%, specificity 96.3%, positive predictive value 83%, negative predictive value 100%. Earlier relapse detection with the test was found in 28%, with non-significant median time gain to diagnosis. Postoperative M371 levels did not predict future relapse.

CONCLUSIONS

The sensitivity and specificity of the M371 test for detecting relapses in CSI GCTs are much superior to those of conventional diagnostics. However, post-orchiectomy M371 levels are not predictive of relapse, and there is no significant earlier relapse detection with the test. In all, there is clear evidence for the utility of the M371 test for relapse detection suggesting it may soon be ready for implementation into routine follow-up schedules for patients with testicular GCT.

Testicular germ cell tumour cells release microRNA-containing extracellular vesicles that induce phenotypic and genotypic changes in cells of the tumour microenvironment

Malignant germ-cell-tumours (GCTs) are characterised by microRNA (miRNA/miR-) dysregulation, with universal over-expression of miR-371~373 and miR-302/367 clusters regardless of patient age, tumour site, or subtype (seminoma/yolk-sac-tumour/embryonal carcinoma). These miRNAs are released into the bloodstream, presumed within extracellular-vesicles (EVs) and represent promising biomarkers. Here, we comprehensively examined the role of EVs, and their miRNA cargo, on (fibroblast/endothelial/macrophage) cells representative of the testicular GCT (TGCT) tumour microenvironment (TME). Small RNA next-generation-sequencing was performed on 34 samples, comprising representative malignant GCT cell lines/EVs and controls (testis fibroblast [Hs1.Tes] cell-line/EVs and testis/ovary samples). TME cells received TGCT co-culture, TGCT-derived EVs, and a miRNA overexpression system (miR-371a-OE) to assess functional relevance. TGCT cells secreted EVs into culture media. MiR-371~373 and miR-302/367 cluster miRNAs were overexpressed in all TGCT cells/subtypes compared with control cells and were highly abundant in TGCT-derived EVs, with miR-371a-3p/miR-371a-5p the most abundant. TGCT co-culture resulted in increased levels of miRNAs from the miR-371~373 and miR-302/367 clusters in TME (fibroblast) cells. Next, fluorescent labelling demonstrated TGCT-derived EVs were internalised by all TME (fibroblast/endothelial/macrophage) cells. TME (fibroblast/endothelial) cell treatment with EVs derived from different TGCT subtypes resulted in increased miR-371~373 and miR-302/367 miRNA levels, and other generic (eg, miR-205-5p/miR-148-3p) and subtype-specific (seminoma, eg, miR-203a-3p; yolk-sac-tumour, eg, miR-375-3p) miRNAs. MiR-371a-OE in TME cells resulted in increased collagen contraction (fibroblasts) and angiogenesis (endothelial cells), via direct mRNA downregulation and alteration of relevant pathways. TGCT cells communicate with nontumour stromal TME cells through release of EVs enriched in oncogenic miRNAs, potentially contributing to tumour progression.

Prognostic Factors for Relapse in Patients With Clinical Stage I Testicular Seminoma: A Nationwide, Population-Based Cohort Study

PURPOSE

Approximately 20% of patients with clinical stage I seminoma relapse. Tumor size and rete testis invasion have been identified as risk factors for relapse. However, the level of evidence supporting the use of these risk factors in clinical decision making is low. Previous studies have been hampered by selection bias and variable pathology reporting that limit interpretation and generalization of results. We assessed prognostic factors for relapse in an unselected nationwide population-based setting with centralized pathology review.

METHODS

Patients with clinical stage I seminoma diagnosed from January 2013 to December 2018 were identified in the prospective Danish Testicular Cancer database. By linkage to the Danish National Pathology Registry, histologic slides from the orchiectomy specimens were retrieved and reviewed blinded to the clinical outcome. Clinical data were obtained from medical records with follow-up until July 2022. The association between prespecified potential clinical and histopathologic prognostic factors and relapse was assessed by the use of Cox regression analysis.

RESULTS

Of 924 patients included, 148 (16%) patients relapsed during a median follow-up of 6.3 years. Invasion of the testicular hilum (rete testis and hilar soft tissue), lymphovascular invasion, and elevated preorchiectomy levels of β-human chorionic gonadotropin and lactate dehydrogenase were independent predictors of relapse. The estimated 5-year risk of relapse ranged from 6% in patients with no risk factors to 62% in patients with all four risk factors with tumor extension into the hilar soft tissue of the testicular hilum. After internal model validation, the prognostic model had an overall concordance statistic of 0.70.

CONCLUSION

The provided prognostic factors could replace current risk factors in guidelines and be used in future studies investigating risk-adapted follow-up and treatment strategies.

Diagnosis and management of indeterminate testicular lesions

The sophistication and accessibility of modern-day imaging result in frequent detection of small or equivocal lesions of the testes. Traditionally, diagnosis of a testicular lesion with any possibility of malignancy would usually prompt radical orchidectomy. However, awareness is growing that a substantial proportion of these lesions might be benign and that universal application of radical orchidectomy risks frequent overtreatment. Given the potentially profound effects of radical orchidectomy on fertility, endocrine function and psychosexual well-being, particularly in scenarios of an abnormal contralateral testis or bilateral lesions, organ-preserving strategies for equivocal lesions should be considered. Image-based active surveillance can be applied for indeterminate lesions measuring ≤15 mm with a low conversion rate to surgical treatment. However, these outcomes are early and from relatively small, selected cohorts, and concerns prevail regarding the metastatic potential of even small undiagnosed germ cell tumours. No consensus exists on optimal surveillance (short interval (<3 months) ultrasonography is generally adopted); histological sampling is a widespread alternative, involving inguinal delivery of the testis and excisional biopsy of the lesion, with preoperative marking or intraoperative ultrasonographic localization when necessary. Frozen section analysis in this context demonstrates excellent diagnostic accuracy. Histological results support that approximately two-thirds of marker-negative indeterminate solitary testicular lesions measuring ≤25 mm overall are benign. In summary, modern imaging detects many small indeterminate testicular lesions, of which the majority are benign. Awareness is growing of surveillance and organ-sparing diagnostic and treatment strategies with the aim of minimizing rates of overtreatment with radical orchidectomy.

The Role of miRNA in Testicular Cancer: Current Insights and Future Perspectives

Background and Objectives: Despite advancements in the diagnosis and treatment of testicular germ cell tumours (TGTCs), challenges persist in identifying reliable biomarkers for early detection and precise disease management. This narrative review addresses the role of microRNAs (miRNAs) as potential diagnostic tools and therapeutic targets in the treatment of TGCTs. Materials and Methods: Three databases (PubMed®, Web of Science™, and Scopus®) were queried for studies investigating the utility of miRNA as diagnostic tools, assessing their prognostic significance, and evaluating their potential to guide TGCT treatment. Different combinations of the following keywords were used, according to a free-text protocol: "miRNA", "non-coding RNA", "small RNA", "Testicular Cancer", "seminomatous testicular germ cell", "non-seminomatous testicular germ cell". Results: The potential of miRNAs as possible biomarkers for a non-invasive diagnosis of TGCT is appealing. Their integration into the diagnostic pathway for TGCT patients holds the potential to enhance the discriminative power of conventional serum tumour markers (STMs) and could expedite early diagnosis, given that miRNA overexpression was observed in 50% of GCNIS cases. Among miRNAs, miR-371a-3p stands out with the most promising evidence, suggesting its relevance in the primary diagnosis of TGCT, particularly when conventional STMs offer limited value. Indeed, it demonstrated high specificity (90-99%) and sensitivity (84-89%), with good positive predictive value (97.2%) and negative predictive value (82.7%). Furthermore, a direct relationship between miRNA concentration, disease burden, and treatment response exists, regardless of disease stages. The initial evidence of miRNA decrease in response to surgical treatment and systemic chemotherapy has been further supported by more recent results suggesting the potential utility of this tool not only in evaluating treatment response but also in monitoring residual disease and predicting disease relapse. Conclusions: MiRNAs could represent a reliable tool for accurate diagnosis and disease monitoring in the treatment of TGCT, providing more precise tools for early detection and treatment stratification. Nevertheless, well-designed clinical trials and comprehensive long-term data are needed to ensure their translation into effective clinical tools.

Molecular Biomarkers With Potential Clinical Application in Testicular Cancer

Testicular germ cell tumors (TGCTs) and sex cord-stromal tumors (SCSTs) are the most common testicular neoplasms. The morphologic spectrum of such tumors is wide, with several histologic subtypes within each group. Testicular tumors often represent a diagnostic challenge, requiring proper identification of their biologic potential for accurate risk stratification and selection of therapy. In the era of precision medicine, molecular biomarkers are increasingly assuming a critical role in the management of patients with cancer. Given the overall rarity of certain types of testicular neoplasms, progress in biomarker research has been relatively slow. However, in recent years, we have witnessed a multitude of important contributions, including both tissue-based and liquid biopsy biomarkers, stemming from important discoveries of tumor pathobiology, accurate histopathological analysis, multi-institutional studies, and genome-wide molecular analyses of specific tumor subtypes. In this review, we provide an overview of the progress in molecular biomarkers of TGCTs and SCSTs, focusing on those with greatest potential for clinical application. In TGCTs, developmental biology has been the key to understanding these tumors and identifying clinically useful biomarkers (from classical serum tumor markers to pluripotency factors and circulating microRNAs of the 371-373 cluster). For SCSTs, studies have focused on tissue biomarkers only, and genome-wide investigations have recently contributed to a better understanding of rare phenotypes and the aggressive biological behavior of some tumors within this nosologic category. Several new biomarkers are moving toward clinical implementation in this field. Therefore, the practicing pathologist should be aware of their strengths and limitations in order to utilize them properly and maximize their clinical benefits.

Children's Oncology Group's 2023 blueprint for research: Germ cell tumors

Extracranial germ cell tumors (GCT) are a biologically diverse group of tumors occurring in children, adolescents, and young adults. The majority of patients have excellent outcomes, but treatment-related toxicities impact their quality of survivorship. A subset of patients succumbs to the disease. Current unmet needs include clarifying which patients can be safely observed after initial surgical resection, refinement of risk stratification to reduce chemotherapy burden in patients with standard-risk disease, and intensify therapy for patients with poor-risk disease. Furthermore, enhancing strategies for detection of minimal residual disease and early detection of relapse, particularly in serum tumor marker-negative histologies, is critical. Improving the understanding of the developmental and molecular origins of GCTs may facilitate discovery of novel targets. Future efforts should be directed toward assessing novel therapies in a biology-driven, biomarker-defined, histology-specific, risk-stratified patient population. Fragmentation of care between subspecialists restricts the unified study of these rare tumors. It is imperative that trials be conducted in collaboration with national and international cooperative groups, with harmonized data and biospecimen collection. Key priorities for the Children's Oncology Group (COG) GCT Committee include (a) better understanding the biology of GCTs, with a focus on molecular targets and mechanisms of treatment resistance; (b) strategic development of pediatric and young adult clinical trials; (c) understanding late effects of therapy and identifying individuals most at risk; and (d) prioritizing diversity, equity, and inclusion to reduce cancer health disparities and studying the impacts of social determinants of health on outcomes.

European Association of Urology Guidelines on Testicular Cancer: 2023 Update

CONTEXT

Each year the European Association of Urology (EAU) produce a document based on the most recent evidence on the diagnosis, therapy, and follow-up of testicular cancer (TC).

OBJECTIVE

To represent a summarised version of the EAU guidelines on TC for 2023 with a focus on key changes in the 2023 update.

EVIDENCE ACQUISITION

A multidisciplinary panel of TC experts, comprising urologists, medical and radiation oncologists, and pathologists, reviewed the results from a structured literature search to compile the guidelines document. Each recommendation in the guidelines was assigned a strength rating.

EVIDENCE SYNTHESIS

For the 2023 EAU guidelines on TC, a review and restructure were undertaken. The key changes incorporated in the 2023 update include: new supporting text regarding venous thromboembolism prophylaxis in males with metastatic germ cell tumours receiving chemotherapy; quality of life after treatment; an update of the histological classifications and inclusion of the World Health Organization 2022 pathological classification; inclusion of the revalidation of the 1997 International Germ Cell Cancer Collaborative Group prognostic risk factors; and a new section covering oncology treatment protocols.

CONCLUSIONS

The 2023 version of the EAU guidelines on TC include the highest available scientific evidence to standardise the management of TC. Better stratification and optimisation of treatment modalities will continue to improve the high survival rates for patients with TC.

PATIENT SUMMARY

This article presents a summary of the European Association of Urology guidelines on testicular cancer published in 2023 and includes the latest recommendations for management of this disease. The guidelines are a valuable resource that may help patients in understanding treatment recommendations.

Hsa_circRNA_0084043 promoting tumorigenesis in glioma through miR-577 sponging

Circular RNAs (circRNAs) are important non-coding RNAs (ncRNAs) involved in the development of multiple human diseases, especially cancers. circRNA_0084043 is significantly involved in the progression of melanoma. However, whether circRNA_0084043 is associated with glioma remains unknown. In this study, the upregulation of circRNA_0084043 in glioma and the association between circRNA_0084043 and glioma grade were identified. Our results showed that circRNA_0084043 is significantly involved in the proliferative, migratory, and invasive capacities of glioma cells. The results obtained from starBase, luciferase reporter assays, RNA immunoprecipitation assays, and RNA pull-down assays demonstrated that circRNA_0084043 acts as a direct sponge for miR-577. TargetScan algorithm was used to identify potential miR-577 targets, it was found that sorting nexin 5 (SNX5) is a candidate bound to miR-577. Finally, cell experiments testified that circRNA_0084043 enhanced growth, migration and invasion of glioma through the regulation of miR-577-mediated SNX5. Taken together, we concluded that circRNA_0084043 in the miR-577/SNX5 axis can be used as a candidate target for glioma therapy.

Testicular neoplasms: the interrelationships of serum levels of microRNA-371a-3p (M371) and classical tumor markers with histology, clinical staging, and age-a statistical analysis

PURPOSE

In testicular neoplasms, the interrelationship of elevations of the novel serum tumor marker microRNA-371a-3p (M371) and traditional markers with other clinical features is still incompletely understood. The present study evaluated marker expression rates in relation to various other clinical parameters.

METHODS

The following data were retrospectively registered from 641 consecutive patients with testicular neoplasms: histology, such as seminoma (n = 365), nonseminoma (n = 179), benign tumor (n = 79), other malignant tumor (n = 18); patients age (years); clinical stage (CS1, CS2a/b, CS2c, CS3); and preoperative elevation of beta HCG, AFP, LDH, M371 (yes/no). Descriptive statistical methods were employed with comparisons of various subgroups to disclose associations of marker expression rates with age, histology and CS, and of age with histology.

RESULTS

The histologic subgroups revealed significantly different expression rates of tumor markers. M371 performed best with expression rates of 82.69% and 93.58% in seminoma and in nonseminoma, respectively. In germ cell tumors, all markers had significantly higher expression rates in metastasized stages than in localized disease. All markers except LDH have significantly higher expression rates in younger than in older patients. Nonseminoma is most prevalent in the youngest age category, seminoma predominates in patients > 40 years, other malignancies were restricted to patients > 50 years.

CONCLUSION

The study documented significant associations of serum marker expression rates with histology, age and clinical staging, with highest rates in nonseminomas, young age and advanced clinical stages. M371 showed significantly higher expression rates than other markers suggesting its superior clinical usefulness.

miRNAs orchestration of testicular germ cell tumors - Particular emphasis on diagnosis, progression and drug resistance

Testicular cancer (TC) is one of the most frequently incident solid tumors in males. A growing prevalence has been documented in developed countries. Although recent advances have made TC an exceedingly treatable cancer, numerous zones in TC care still have divisive treatment decisions. In addition to physical examination and imaging techniques, conventional serum tumor markers have been traditionally used for the diagnosis of testicular germ cell tumors (TGCT). Unlike other genital and urinary tract tumors, recent research methods have not been broadly used in TGCTs. Even though several challenges in TC care must be addressed, a dedicated group of biomarkers could be particularly beneficial to help classify patient risk, detect relapse early, guide surgery decisions, and tailor follow-up. Existing tumor markers (Alpha-fetoprotein, human chorionic gonadotrophin, and lactate dehydrogenase) have limited accuracy and sensitivity when used as diagnostic, prognostic, or predictive markers. At present, microRNAs (miRNA or miR) play a crucial role in the process of several malignancies. The miRNAs exhibit pronounced potential as novel biomarkers since they reveal high stability in body fluids, are easily detected, and are relatively inexpensive in quantitative assays. In this review, we aimed to shed light on the recent novelties in developing microRNAs as diagnostic and prognostic markers in TC and discuss their clinical applications in TC management.

Male Infertility and the Risk of Developing Testicular Cancer: A Critical Contemporary Literature Review

Background and Objectives: The relationship between male infertility (MI) and testicular cancer (TC) is bilateral. On one hand, it is well-established that patients diagnosed with TC have a high risk of pre- and post-treatment infertility. On the other hand, the risk of developing TC in male infertile patients is not clearly defined. The objective of this review is to analyze the histopathological, etiological, and epidemiological associations between MI and the risk of developing testicular cancer. This review aims to provide further insights and offer a guide for assessing the risk factors for TC in infertile men. Materials and Methods: A comprehensive literature search was conducted to identify relevant studies discussing the relationship between MI and the risk of developing TC. Results: The incidence rates of germ cell neoplasia in situ (GCNIS) appear to be high in infertile men, particularly in those with low sperm counts. Most epidemiological studies have found a statistically significant risk of developing TC among infertile men compared to the general or fertile male populations. The concept of Testicular Dysgenesis Syndrome provides an explanatory model for the common etiology of MI, TC, cryptorchidism, and hypospadias. Clinical findings such as a history of cryptorchidism could increase the risk of developing TC in infertile men. Scrotal ultrasound evaluation for testis lesions and microlithiasis is important in infertile men. Sperm analysis parameters can be useful in assessing the risk of TC among infertile men. In the future, sperm and serum microRNAs (miRNAs) may be utilized for the non-invasive early diagnosis of TC and GCNIS in infertile men. Conclusions: MI is indeed a risk factor for developing testicular cancer, as demonstrated by various studies. All infertile men should undergo a risk assessment using clinical examination, ultrasound, and semen parameters to evaluate their risk of TC.

Absolute monocyte count has a diagnostic role in distinguishing tumor marker-negative TGCT from benign testicular tumor via CCL2 regulation

Clinically, for testicular tumor patients with negative tumor markers, how to distinguish the malignant from the benign is a difficult problem. This study aimed to assess the clinical significance of the absolute monocyte count (AMC) in differential diagnosis of testicular germ cell tumor with stage S0 (TGCTS0) and benign testicular tumor. In this retrospective single-center study, a total of 90 patients newly diagnosed with benign testicular tumor or TGCTS0 were reviewed. All patients received surgical intervention as the primary treatment method. AMC and other clinicopathological parameters were analyzed. Receiver operating characteristic (ROC) curves were constructed to assess the diagnostic power of investigated parameters, and to determine the optimal cutoff values. Kaplan-Meier curve analysis was used to study the survival of patients with TGCTS0. qRT-PCR and immunohistochemistry (IHC) were performed to examine the expression of C-C motif chemokine ligand 2 (CCL2) mRNA and protein respectively. Differential gene expression and functional enrichment analysis were performed using Gene Expression Omnibus and the Cancer Genome Atlas databases. The mean preoperative AMC in patients with TGCTS0 was significantly higher than that in patients with benign testicular tumor (P = .020). AMC > 0.485*10^9/L was identified to be associated with the presence of TGCTS0 (hazard ratio [HR] = 3.074, P = .026), and patients with higher AMC level had worse progression free survival (PFS) (P = .047). Furthermore, AMC combined with lactate dehydrogenase (LDH) achieved a better diagnostic efficacy for TGCTS0 (area under curve [AUC] = 0.695). Tumor-associated macrophages (TAMs) signature gene CCL2 was highly expressed in TGCT compared with normal testicular tissue. Functional enrichment analysis showed that CCL2 is closely involved in the Extracellular Matrix Organization pathway and positively correlated with the expression of various matrix metalloproteinases (MMPs). Elevated AMC may serve as a predictor of higher risk of TGCTS0, and CCL2 mediated TAMs infiltration and MMPs secretion is essential for the tumorigenesis of TGCT.

Circulating microRNAs as diagnostic biomarkers for melanoma: a systematic review and meta-analysis

BACKGROUND

Recent studies have shown that circulating microRNAs (miRNAs) can be used as diagnostic biomarkers for melanoma. This study aimed to evaluate the diagnostic value of circulating miRNAs for melanoma.

METHODS

A comprehensive literature search was conducted and the quality of the included literature was evaluated using QUADAS-2 (Quality Assessment for diagnostic accuracy studies), and the diagnostic accuracy was assessed by pooled sensitivity, specificity, positive likelihood ratio (PLR), negative likelihood ratio (NLR), diagnostic odds ratio (DOR), and area under the curve (AUC). We used Deeks' funnel plot to evaluate publication bias.

RESULTS

The meta-analysis included 10 articles covering 16 studies, and the results showed that circulating miRNAs provide high diagnostic accuracy for melanoma. The overall pooled sensitivity was 0.87 (95% CI: 0.82-0.91), specificity was 0.81 (95% CI: 0.77-0.85), PLR was 4.6 (95% CI: 3.7-5.8), NLR was 0.16 (95% CI: 0.11-0.23), DOR was 29 (95% CI: 18-49), and AUC was 0.90 (95% CI: 0.87-0.92), respectively. Subgroup analysis showed better diagnostic value in miRNA clusters, European population, plasma miRNAs, and upregulated miRNAs compared to other subgroups.

CONCLUSIONS

The results indicated that circulating microRNAs can be used as a non-invasive biomarker for the diagnosis of melanoma.

Circulating microRNAs as promising testicular translatable safety biomarkers: current state and future perspectives

Drug-induced testicular injury (DITI) is one of the often-observed and challenging safety issues seen during drug development. Semen analysis and circulating hormones currently utilized have significant gaps in their ability to detect testicular damage accurately. In addition, no biomarkers enable a mechanistic understanding of the damage to the different regions of the testis, such as seminiferous tubules, Sertoli, and Leydig cells. MicroRNAs (miRNAs) are a class of non-coding RNAs that modulate gene expression post-transcriptionally and have been indicated to regulate a wide range of biological pathways. Circulating miRNAs can be measured in the body fluids due to tissue-specific cell injury/damage or toxicant exposure. Therefore, these circulating miRNAs have become attractive and promising non-invasive biomarkers for assessing drug-induced testicular injury, with several reports on their use as safety biomarkers for monitoring testicular damage in preclinical species. Leveraging emerging tools such as 'organs-on-chips' that can emulate the human organ's physiological environment and function is starting to enable biomarker discovery, validation, and clinical translation for regulatory qualification and implementation in drug development.

The Value of Tumour Markers in the Detection of Relapse-Lessons Learned from the Swiss Austrian German Testicular Cancer Cohort Study

The tumour markers alpha-fetoprotein (AFP), beta human chorionic gonadotropin (βHCG), and lactate dehydrogenase (LDH) have established roles in the management and follow-up of testicular cancer. While a tumour marker rise can serve as an indicator of relapse, the frequency of false-positive marker events has not been studied systematically in larger cohorts. We assessed the validity of serum tumour markers for the detection of relapse in the Swiss Austrian German Testicular Cancer Cohort Study (SAG TCCS). This registry was set up to answer questions on the diagnostic performance and impact of imaging and laboratory tests in the management of testicular cancer, and has included 948 patients between January 2014 and July 2021.A total of 793 patients with a median follow-up of 29.0 mo were included. In total, 71 patients (8.9%) had a proven relapse, which was marker positive in 31 patients (43.6%). Of all patients, 124 (15.6%) had an event of a false-positive marker elevation. The positive predictive value (PPV) of the markers was limited, highest for βHCG (33.8%) and lowest for LDH (9.4%). PPV tended to increase with higher levels of elevation. These findings underline the limited accuracy of the conventional tumour markers to indicate or rule out a relapse. Especially, LDH as part of routine follow-up should be questioned.

Patient summary

With the diagnosis of testicular cancer, the three tumour markers alpha-fetoprotein, beta human chorionic gonadotropin, and lactate dehydrogenase are routinely measured during follow-up to monitor for relapse. We demonstrate that these markers are often falsely elevated, and, by contrast, many patients do not have marker elevations despite a relapse. The results of this study can lead to improved use of these tumour markers during follow-up of testis cancer patients.

Small Testicular Masses: Contemporary Diagnostic and Treatment Strategies, Future Directions, and Knowledge Gaps

The incidental discovery of small masses in the testicles of young men is becoming an increasing clinical dilemma. We are learning that the malignancy rate in masses ≤ 2 cm is much lower than traditionally thought and could be as low as 13% to 21%. The challenge remains in identifying which of these patients harbor malignant tumors that need to be treated, and benign lesions that could be safely surveilled. The aim of this narrative review is to discuss the current scientific evidence, diagnostic work-up, and treatment strategies for small testicular masses. We also discuss selection criteria, follow-up schedules and triggers for intervention for the surveillance of these small testis masses. Furthermore, we give a set of recommendations for assessing and treating these patients, based on the available literature and our experience at a dedicated testicular cancer clinic.

An update on diagnostic tissue-based biomarkers in testicular tumors

Testicular cancer is rare overall but comprises the most common solid malignancy diagnosed in young men aged ∼20-40 years. Most testicular neoplasms generally fall into 2 broad categories: germ cell tumors (GCTs; ∼95%) and sex cord-stromal tumors (SCSTs ∼5%). Given the relative rarity of these tumors, diagnostic biomarkers are highly relevant for their diagnosis. Over the past several decades, diagnostic biomarkers have improved dramatically through targeted immunohistochemical and molecular characterization. Despite these recent advances, most markers are not perfectly sensitive or entirely specific. Therefore, they need to be used in combination and interpreted in context. In this review, we summarize tissue-based biomarkers relevant to the pathologist, with a focus on practical diagnostic issues that relate to testicular GCT and SCST.

Aberrant Methylation of the Imprinted C19MC and MIR371-3 Clusters in Patients with Non-Small Cell Lung Cancer

Epigenetic mechanisms have emerged as an important contributor to tumor development through the modulation of gene expression. Our objective was to identify the methylation profile of the imprinted C19MC and MIR371-3 clusters in patients with non-small cell lung cancer (NSCLC) and to find their potential target genes, as well as to study their prognostic role. DNA methylation status was analyzed in a NSCLC patient cohort (n = 47) and compared with a control cohort including COPD patients and non-COPD subjects (n = 23) using the Illumina Infinium Human Methylation 450 BeadChip. Hypomethylation of miRNAs located on chromosome 19q13.42 was found to be specific for tumor tissue. We then identified the target mRNA-miRNA regulatory network for the components of the C19MC and MIR371-3 clusters using the miRTargetLink 2.0 Human tool. The correlations of miRNA-target mRNA expression from primary lung tumors were analyzed using the CancerMIRNome tool. From those negative correlations identified, we found that a lower expression of 5 of the target genes (FOXF2, KLF13, MICA, TCEAL1 and TGFBR2) was significantly associated with poor overall survival. Taken together, this study demonstrates that the imprinted C19MC and MIR371-3 miRNA clusters undergo polycistronic epigenetic regulation leading to deregulation of important and common target genes with potential prognostic value in lung cancer.

Balancing efficacy with long-term side-effects: can we safely de-escalate therapy for germ cell tumors?

INTRODUCTION

The success in the management of germ cell tumors has encouraged researchers to pay more attention on long-term side effects and other survivorship issues. The de-escalation of treatment is intended to reduce side effects but must be balanced against any compromise of efficacy. Cisplatin-based therapy is the cornerstone of treatment for germ cell tumors. However, they can result in acute and long-term side effects, including ototoxicity, neurotoxicity, nephrotoxicity, and increased risk of second malignancies.

AREAS COVERED

This review discusses approaches of de-escalation including biomarker-directed treatment using microRNAs, surveillance for immature teratoma, the use of carboplatin monotherapy for seminoma, and the option of non-cisplatin-based approaches in relapsed germ cell tumors.

EXPERT OPINION

While the results with the current standard options in terms of cancer control are very good, the price being paid in terms of long-term side effects is considerable.

Integrated Microarray-Based Data Analysis of miRNA Expression Profiles: Identification of Novel Biomarkers of Cisplatin-Resistance in Testicular Germ Cell Tumours

Testicular germ cell tumours (TGCTs) are the most common solid malignancy among young men, and their incidence is still increasing. Despite good curability with cisplatin (CDDP)-based chemotherapy, about 10% of TGCTs are non-responsive and show a chemoresistant phenotype. To further increase TGCT curability, better prediction of risk of relapse and early detection of refractory cases is needed. Therefore, to diagnose this malignancy more precisely, stratify patients more accurately and improve decision-making on treatment modality, new biomarkers are still required. Numerous studies showed association of differential expressions of microRNAs (miRNAs) with cancer. Using microarray analysis followed by RT-qPCR validation, we identified specific miRNA expression patterns that discriminate chemoresistant phenotypes in TGCTs. Comparing CDDP-resistant vs. -sensitive TGCT cell lines, we identified miR-218-5p, miR-31-5p, miR-125b-5p, miR-27b-3p, miR-199a-5p, miR-214-3p, let-7a and miR-517a-3p as significantly up-regulated and miR-374b-5p, miR-378a-3p, miR-20b-5p and miR-30e-3p as significantly down-regulated. In patient tumour samples, we observed the highest median values of relative expression of miR-218-5p, miR-31-5p, miR-375-5p and miR-517a-3p, but also miR-20b-5p and miR-378a-3p, in metastatic tumour samples when compared with primary tumour or control samples. In TGCT patient plasma samples, we detected increased expression of miR-218-5p, miR-31-5p, miR-517a-3p and miR-375-5p when compared to healthy individuals. We propose that miR-218-5p, miR-31-5p, miR-375-5p, miR-517-3p, miR-20b-5p and miR-378a-3p represent a new panel of biomarkers for better prediction of chemoresistance and more aggressive phenotypes potentially underlying metastatic spread in non-seminomatous TGCTs. In addition, we provide predictions of the targets and functional and regulatory networks of selected miRNAs.

LINC02535/miR-30a-5p/GALNT3 axis contributes to lung adenocarcinoma progression via the NF- κ B signaling pathway

Long non-coding RNAs (LncRNA) play important roles in multiple types of cancers. We addressed the role of LINC02535 by regulating the miR-30a-5p /GalNAc Transferase 3 (GALNT3) axis to promote the proliferation, migration, and invasion in lung adenocarcinoma (LUAD) cells. The Cancer Genome Atlas (TCGA) database screened differentially expressed lncRNAs. Quantitative real-time PCR analysis (qRT-PCR) confirmed that LINC02535 is highly expressed in LUAD tissues and cells. In vitro experiments showed that LINC02535 promotes the proliferation, migration, and invasion of LUAD cells. A xenograft mouse model was used to show that LINC02535 promotes tumor growth in vivo. RNA immunoprecipitation (RIP) and Dual-luciferase reporter assay results confirmed that LINC02535 targets miR-30a-5p. The Vicia villosa lectin (VVA) pull-down assay indicated that MUC1 is the glycosylation target of GALNT3, and western blot verified that NF-κB is the downstream signaling pathway of MUC1. We found that LINC02535 was increased in LUAD tissues and cells, and LINC02535 was correlated with the poor prognosis of LUAD patients. miR-30a-5p acts as a tumor suppressor in LUAD by targeting GALNT3. We also demonstrated that LINC02535 might function as the sponge of miR-30a-5p to up-regulate GALNT3, and consequently promote the proliferation and metastasis of LUAD. LINC02535 acts as a competing endogenous RNA (ceRNA) to interact with miR-30a-5p, thereby upregulating the expression of GALNT3, enhancing the function of MUC1, and activating the NF-κB signaling pathway, promoting the malignant progression of LUAD cells.Abbreviations: LncRNA:long non-coding RNA; LUAD: lung adenocarcinoma; TCGA: The Cancer Genome Atlas; GALNT3: GalNAc Transferase 3; qRT-PCR: quantitative real-time PCR analysis; RIP: RNA immunoprecipitation; SPF: specific pathogen-free; VVA: Vicia villosa lectin; ceRNA: competing endogenous RNA; MiRNAs: microRNAs; FBS: fetal bovine serum; PBS: Phosphate buffered saline; CCK-8: Cell Counting Kit-8; NSCLC: non-small cell lung cancer; OC: ovarian cancer; HCC: hepatocellular carcinoma.

Testicular Neoplasms: Primary Tumour Size Is Closely Interrelated with Histology, Clinical Staging, and Tumour Marker Expression Rates-A Comprehensive Statistical Analysis

The role of primary tumour size (TS) in the clinical course of testicular tumours is incompletely understood. We retrospectively evaluated 641 consecutive patients with testicular neoplasms with regard to TS, histology, clinical stage (CS), serum tumour marker (STM) expression and patient age using descriptive statistical methods. TS ≤ 10 mm was encountered in 13.6% of cases. Median TS of 10 mm, 30 mm, 35 mm, and 53 mm were found in benign tumours, seminomas, nonseminomas, and other malignant tumours, respectively. In cases with TS ≤ 10 mm, 50.6% had benign tumours. Upon receiver operating characteristics analysis, TS of > 16 mm revealed 81.5% sensitivity and 81.0% specificity for detecting malignancy. In subcentimeter germ cell tumours (GCTs), 97.7% of cases had CS1, and CS1 frequency dropped with increasing TS. Expression rates of all STMs significantly increased with TS. MicroRNA-371a-3p (M371) serum levels had higher expression rates than classical STMs, with a rate of 44.1% in subcentimeter GCTs. In all, TS is a biologically relevant factor owing to its significant associations with CS, STM expression rates and histology. Importantly, 50% of subcentimeter testicular neoplasms are of benign nature, and M371 outperforms the classical markers even in subcentimeter tumours.

Advancing clinical and translational research in germ cell tumours (GCT): recommendations from the Malignant Germ Cell International Consortium

Germ cell tumours (GCTs) are a heterogeneous group of rare neoplasms that present in different anatomical sites and across a wide spectrum of patient ages from birth through to adulthood. Once these strata are applied, cohort numbers become modest, hindering inferences regarding management and therapeutic advances. Moreover, patients with GCTs are treated by different medical professionals including paediatric oncologists, neuro-oncologists, medical oncologists, neurosurgeons, gynaecological oncologists, surgeons, and urologists. Silos of care have thus formed, further hampering knowledge dissemination between specialists. Dedicated biobank specimen collection is therefore critical to foster continuous growth in our understanding of similarities and differences by age, gender, and site, particularly for rare cancers such as GCTs. Here, the Malignant Germ Cell International Consortium provides a framework to create a sustainable, global research infrastructure that facilitates acquisition of tissue and liquid biopsies together with matched clinical data sets that reflect the diversity of GCTs. Such an effort would create an invaluable repository of clinical and biological data which can underpin international collaborations that span professional boundaries, translate into clinical practice, and ultimately impact patient outcomes.