Perspectives on a Global Change in Testicular Cancer Incidence

Cancer burden in adolescents and young adults in Europe

BACKGROUND

Cancer epidemiology is unique in adolescents and young adults (AYAs; aged 15-39 years). The European Society for Medical Oncology/European Society for Paediatric Oncology (ESMO/SIOPE) AYA Working Group aims to describe the burden of cancers in AYAs in Europe and across European Union (EU) countries.

PATIENTS AND METHODS

We used data available on the Global Cancer Observatory. We retrieved crude and age-standardised (World Standard Population) incidence and mortality rates. We reported about AYA cancer burden in Europe and between 28 EU member states. We described incidence and mortality for all cancers and for the 13 cancers most relevant to the AYA population.

RESULTS

Incidence and mortality varied widely between countries with the highest mortality observed in Eastern EU countries. Cancers of the female breast, thyroid and male testis were the most common cancers across countries followed by melanoma of skin and cancers of the cervix. Variations in cancer incidence rates across different populations may reflect different distribution of risk factors, variations in the implementation or uptake of screening as well as overdiagnosis. AYA cancer mortality disparities may be due to variation in early-stage diagnoses, different public education and awareness of cancer symptoms, different degrees of access or availability of treatment.

CONCLUSIONS

Our results highlight the future health care needs and requirements for AYA-specialised services to ensure a homogeneous treatment across different countries as well as the urgency for preventive initiatives that can mitigate the increasing burden.

Characteristics of lung metastasis in testicular cancer: A large-scale population analysis based on propensity score matching

Background

This study aims to systematically evaluate predictive factors for lung metastasis (LM) in patients with testicular cancer (TC) and to investigate cancer-specific survival (CSS) and overall survival (OS) of LM in TC patients based on a large population-cohort.

Methods

A total of 10,414 patients diagnosed with TC during 2010–2015 were adopted from the Surveillance, Epidemiology, and End Results (SEER). After propensity score matching (PSM), 493 patients with LM were included for subsequent analysis. Univariate and multivariate logistic regression analyses were employed to identify risk factors, a nomogram was developed, and the receiver operating characteristic (ROC) curve was utilized to confirm the validation of the nomogram. Prognostic factors for OS and CSS among TC patients with LM were estimated via Cox proportional hazards models.

Results

Postmatching indicated that 11 parameters were successfully balanced between both groups (P > 0.05). After PSM, TC patients with LM presented an undesirable prognosis in both CSS and OS than those without LM (P < 0.001). The logistic regression model showed that tumor size; T stage; N stage; liver, brain, and bone metastases; and histology were positively associated with LM (P < 0.05). A nomogram was developed to predict diagnostic possibilities based on the independent risk variables, and the ROC curve verified the predictive capacity of the logistic regression model [area under the curve (AUC) = 0.910].

Conclusion

The selected variates in the nomogram can be predictive criteria for TC patients with LM. Brain metastasis, liver metastasis, and larger tumor size were prognostic factors for CCS and OS among TC patients with LM.

Trends of Testicular Cancer Mortality-to-Incidence Ratios in Relation to Health Expenditure: An Ecological Study of 54 Countries

Favorable testicular cancer mortality-to-incidence ratios (MIRs) are associated with health care disparities, including health care expenditures, but the trends of testicular MIR and health care disparity remain unclear. We evaluated changes in MIR as the difference between 2012 and 2018, termed delta MIR (δMIR). Health care expenditures and the human development index (HDI) were obtained from the World Health Organization and the Human Development Report Office of the United Nations Development Programme. The association between the variables was analyzed by Spearman's rank correlation coefficient. A total of 54 countries were included in the criteria of data quality reports and missing data. By continent, the most favorable MIR was in Oceania (0.03) while it was 0.36 in Africa. In these areas, the incidence rates were positively correlated to health care expenditure, but the mortality rates showed a reversed correlation. The MIR ranged from 0.01 to 0.34 and the δMIR ranged from -0.05 to 0.34. The favorable MIRs are correlated to high health care expenditure and HDI (all p < 0.001). Interestingly, favorable δMIRs tend to be seen in countries with relatively low health care expenditure and HDI (all p < 0.001). In conclusion, favorable testicular cancer MIRs are associated with high HDI and health care expenditure, but the improvement in MIR between 2012 and 2018 (δMIR) is negatively correlated with HDI and health care expenditure.

Identification of novel genes in testicular cancer microenvironment based on ESTIMATE algorithm-derived immune scores

Testicular cancer is the most common solid malignancy among young men. We downloaded data of testicular cancer patients from The Cancer Genome Atlas database to find novel genes in the testicular cancer microenviroment based on ESTIMATE algorithm-derived immune scores. A total of 156 cases of testicular cancer were included in this study and 165 cases of normal testicular tissues were used. We divided the testicular cancer patients into high- and low-score groups based on their immune scores. We identified 1,226 differentially expressed genes (fold change > 2, false discovery rate < 0.05), including 688 downregulated genes and 538 upregulated genes, between these two groups. The top Gene Ontology terms were involved in the immune response-regulating cell surface receptor signaling pathway, immune response-activating cell surface receptor signaling pathway, external side of the plasma membrane, and receptor ligand activity. By performing the Kyoto Encyclopedia of Genes and Genomes analysis, we demonstrated that cAMP signaling pathway was highly enriched among these differentially expressed genes. High expression of LINC01564, LINC02208, ODAM, RNA5SP111, and RNU6-196P were found to be associated with poor overall survival. The expression of genes was further validated by the Human Protein Atlas and only ALB and IFNG were demonstrated to be differentially expressed between testis tissue and testicular cancer tissue.