Risk of second primary cancers after testicular cancer in East and West Germany: a focus on contralateral testicular cancers

Causes of death among patients with testicular cancer during the survivorship

OBJECTIVE

The aim was to evaluate the causes of death for patients with testicular cancer (TC), and calculate mortality risks for each cause.

METHODS

Patients diagnosed between 2000 and 2017 were identified. Main causes of death including TC, second malignant tumor (SMT) and non-tumor diseases, and the standardized mortality rate (SMR) of each cause were analyzed.

RESULTS

27,143 patients with localized TC were included, and 1171 of them died including 215 TC deaths, 236 SMT deaths, and 720 non-tumor deaths. Main SMT deaths were cancer from lung and bronchus, colon and rectum, etc. Main non-cancer causes were diseases of heart, accidents and adverse effects and suicide and self-inflicted injury. Compared with the general population, the mortality risks from diseases of heart and accidents and adverse effects were significantly reduced. For 11,719 patients with regional and distant metastasis TC, 1733 died including 964 TC deaths, 345 SMT deaths and 424 non-tumor deaths. The main SMT and non-tumor deaths were lung and bronchus, diseases of heart and suicide and self-inflicted injury.

CONCLUSION

The leading causes of death besides TC were lung and bronchus cancer, colon and rectum cancer, diseases of heart, accidents and adverse effects, suicide and self-inflicted injury for TC patients. The localized TC patients were associated with similar risks of SMT deaths and lower risks of main non-tumor causes of death.

IMPACT

We evaluated all causes of death of TC patients and SMR for each cause of death. Our results could provide valuable information about the priority of healthcare during testicular cancer survival.

Skin cancer risk among testicular germ-cell cancer survivors: a systematic review and meta-analysis

Testicular germ-cell tumours (TGCT) are the most common cancer among young adult men. Previous studies suggested TGCT survivors have an increased risk for skin cancer. The goal of this study was to systematically review the literature and evidence regarding skin cancer risk among TGCT survivors compared with the general population. PubMed, EMBASE, Web of Science, Cochrane Databases and reference lists were included in the search. A systematic review of all comparative studies with more than 10 TGCT survivors reporting on skin cancer incidence was performed. A meta-analysis of the Standardized Incidence Rate (SIR) was calculated by pooling study-specific log-transformed estimates using the random-effects model. Risk of bias was assessed using the Newcastle-Ottawa Quality Assessment Scale. Nineteen studies that reported on 147 935 TGCT survivors were included. Pooled SIR for skin cancer and for melanoma incidence among TGCT survivors were 1.93 (95% CI 1.62-2.29, P < 0.0001) and 1.81 (95% CI 1.57-2.08, P < 0.0001), respectively. In conclusion, compared to the general population, TGCT survivors have an increased risk for developing skin cancer and melanoma. Additional long-term studies that include TGCT survivors, additional risk factors and all subtypes of skin cancer are required.

Incidence and clinical pattern of contralateral synchronous and metachronous germ cell testicular cancer

BACKGROUND

Incidence of a second testicular tumor is higher in patients diagnosed with testicular cancer than in the general population. As incidence of unilateral germ cell cancer is increasing worldwide and most of these patients are cured, a growing number of patients at risk of developing a contralateral testis cancer is expected.

OBJECTIVE

To analyze clinical and histological characteristics, as well as the absolute and cumulative incidence of a second testicular cancer in a cohort of 3,834 patients diagnosed with germ cell testicular cancer between I/1994 and I/2018 in 18 referral hospitals of the Spanish Germ Cell Cancer Group.

METHODS

Patients were treated according to stage and year of diagnoses. Contralateral testis biopsy was not routinely performed, according to European Association of Urology rules. Follow-up of the contra lateral testis consists of a physical exam only and an annual optional testicular ultrasound for 10 years.

RESULTS

Median age of the patients included was 32 years (18-82). With a median follow-up of 61 months (0-240), 67/3,834 patients (1.74%) were diagnosed with a second testicular tumor. The second testicular tumor was synchronic (diagnosed within 6 months of the first orchiectomy) in 19 patients, and metachronous in 48. Pathology of the second tumor was reported as a seminomatous testis tumor in 47 patients and a nonseminomatous cancer in 20. Cumulative incidence of contralateral testicular cancer was 2% at 5 years, and 4% (IC 95% 3%-5%) at 14 years. Younger age was a risk factor for developing a second testicular tumor (P = 0.006), whereas chemotherapy reduced the risk for a metachronous testicular cancer (P = 0.046). Within our cohort, 6 families with testicular cancer aggregation (more than 2 tumors in the same family) were identified.

CONCLUSIONS

Incidence of second testicular neoplasm in this cohort of 3,834 patients was similar to that which has been reported in other countries. Metachronous tumors and seminomas are more common. Follow-up of the contralateral testis is mandatory, as well as adequate information for patients to prevent a second neoplasm if feasible, and to detect and treat it as soon as possible.

Intratumoural immune cell landscape in germinoma reveals multipotent lineages and exhibits prognostic significance

AIMS

Alterations in microenvironments are a hallmark of cancer, and these alterations in germinomas are of particular significance. Germinoma, the most common subtype of central nervous system germ cell tumours, often exhibits massive immune cell infiltration intermingled with tumour cells. The role of these immune cells in germinoma, however, remains unknown.

METHODS

We investigated the cellular constituents of immune microenvironments and their clinical impacts on prognosis in 100 germinoma cases.

RESULTS

Patients with germinomas lower in tumour cell content (i.e. higher immune cell infiltration) had a significantly longer progression-free survival time than those with higher tumour cell contents (P = 0.03). Transcriptome analyses and RNA in-situ hybridization indicated that infiltrating immune cells comprised a wide variety of cell types, including lymphocytes and myelocyte-lineage cells. High expression of CD4 was significantly associated with good prognosis, whereas elevated nitric oxide synthase 2 was associated with poor prognosis. PD1 (PDCD1) was expressed by immune cells present in most germinomas (93.8%), and PD-L1 (CD274) expression was found in tumour cells in the majority of germinomas examined (73.5%).

CONCLUSIONS

The collective data strongly suggest that infiltrating immune cells play an important role in predicting treatment response. Further investigation should lead to additional categorization of germinoma to safely reduce treatment intensity depending on tumour/immune cell balance and to develop possible future immunotherapies.

An Uncommon Presentation of a Metachronous Testicular Primary Nonseminoma and Seminoma Separated by Two Decades and a Testicular Cancer Literature Review

Introduction

Testicular cancer is the most common malignancy in men aged 15–40 years [Bols et al.: Philadelphia, Wolters Kluwer, Lippincott Williams & Wilkins, 2011]. Its incidence comprises 0.8% of all male cancers worldwide, with a mortality rate of 0.1%. The incidence has nearly doubled from 1975 to 2007 leading to the concern of environmental causes [Thomas: Am J Epidemiol 2013; 178: 1240–1245]. Testicular cancer presents as a painless testicular mass without transillumination. Testicular cancer is subcategorized under germ cell testicular cancer or sex cord-stromal tumors. Of the germ cell tumors, approximately 90% originate in the testis, with the other 10% being extragonadal [Bols et al.: Philadelphia, Wolters Kluwer, Lippincott Williams & Wilkins, 2011]. Typically, if a patient presents with a testicular mass and is 50 years old or older, the diagnosis of a primary lymphoma is considered until proven otherwise [Bols et al.: Philadelphia, Wolters Kluwer, Lippincott Williams & Wilkins, 2011]. Germ cell testicular cancer is further divided into the subtypes of seminomatous and nonseminomatous; each presents with a unique histology and differing treatment implications.

Discussion

Given the uniqueness of our patient's metachronous second testicular primary, we sought to compare our case findings to available historic publications. We sought to address the issues of the incidence of a second primary testicular malignancy with regard to varying histology, age of incidence, and timing of a second primary testicular cancer, the presence of bowel involvement, and finally a brief discussion of testosterone replacement therapy.

Conclusion

A review of our case presents several unique factors. The above varying literature has shown our patient to have met the odds of a contralateral testicular primary development in that he had a nonseminomatous primary, followed by a second testicular primary seminoma. Our patient exceeded the 15-year cumulative risk of contralateral metachronous testicular cancer of 1.9% versus the seemingly contradictory 5.2% cumulative risk 25 years after the first testicular germ cell tumor. With his second primary (seminoma), he presented with the common retroperitoneal landing zone site, though with an uncommon involvement of the gastrointestinal tract (<1%) and rare incidence of involving the duodenum.

Rare disruptive mutations in ciliary function genes contribute to testicular cancer susceptibility

Testicular germ cell tumour (TGCT) is the most common cancer in young men. Here we sought to identify risk factors for TGCT by performing whole-exome sequencing on 328 TGCT cases from 153 families, 634 sporadic TGCT cases and 1,644 controls. We search for genes that are recurrently affected by rare variants (minor allele frequency <0.01) with potentially damaging effects and evidence of segregation in families. A total of 8.7% of TGCT families carry rare disruptive mutations in the cilia-microtubule genes (CMG) as compared with 0.5% of controls (P=2.1 × 10-8). The most significantly mutated CMG is DNAAF1 with biallelic inactivation and loss of DNAAF1 expression shown in tumours from carriers. DNAAF1 mutation as a cause of TGCT is supported by a dnaaf1hu255h(+/-) zebrafish model, which has a 94% risk of TGCT. Our data implicate cilia-microtubule inactivation as a cause of TGCT and provide evidence for CMGs as cancer susceptibility genes.

The genomic landscape of testicular germ cell tumours: from susceptibility to treatment

The genomic landscape of testicular germ cell tumour (TGCT) can be summarized using four overarching hypotheses. Firstly, TGCT risk is dominated by inherited genetic factors, which determine nearly half of all disease risk and are highly polygenic in nature. Secondly KIT-KITLG signalling is currently the major pathway that is implicated in TGCT formation, both as a predisposition risk factor and a somatic driver event. Results from genome-wide association studies have also consistently suggested that other closely related pathways involved in male germ cell development and sex determination are associated with TGCT risk. Thirdly, the method of disease formation is unique, with tumours universally stemming from a noninvasive precursor lesion, probably of fetal origin, which lies dormant through childhood into adolescence and then eventually begins malignant growth in early adulthood. Formation of a 12p isochromosome, a hallmark of TGCT observed in nearly all tumours, is likely to be a key triggering event for malignant transformation. Finally, TGCT have been shown to have a distinctive somatic mutational profile, with a low rate of point mutations contrasted with frequent large-scale chromosomal gains. These four hypotheses by no means constitute a complete model that explains TGCT tumorigenesis, but advances in genomic technologies have enabled considerable progress in describing and understanding the disease. Further advancing our understanding of the genomic basis of TGCT offers a clear opportunity for clinical benefit in terms of preventing invasive cancer arising in young men, decreasing the burden of chemotherapy-related survivorship issues and reducing mortality in the minority of patients who have treatment-refractory disease.

Malignant testicular tumour incidence and mortality trends

Aim of the study

In Poland testicular tumours are the most frequent cancer among men aged 20–44 years. Testicular tumour incidence since the 1980s and 1990s has been diversified geographically, with an increased risk of mortality in Wielkopolska Province, which was highlighted at the turn of the 1980s and 1990s. The aim of the study was the comparative analysis of the tendencies in incidence and death rates due to malignant testicular tumours observed among men in Poland and in Wielkopolska Province.

Material and methods

Data from the National Cancer Registry were used for calculations. The incidence/mortality rates among men due to malignant testicular cancer as well as the tendencies in incidence/death ratio observed in Poland and Wielkopolska were established based on regression equation. The analysis was deepened by adopting the multiple linear regression model. A p-value < 0.05 was arbitrarily adopted as the criterion of statistical significance, and for multiple comparisons it was modified according to the Bonferroni adjustment to a value of p < 0.0028. Calculations were performed with the use of PQStat v1.4.8 package.

Results

The incidence of malignant testicular neoplasms observed among men in Poland and in Wielkopolska Province indicated a significant rising tendency. The multiple linear regression model confirmed that the year variable is a strong incidence forecast factor only within the territory of Poland. A corresponding analysis of mortality rates among men in Poland and in Wielkopolska Province did not show any statistically significant correlations.

Conclusions

Late diagnosis of Polish patients calls for undertaking appropriate educational activities that would facilitate earlier reporting of the patients, thus increasing their chances for recovery. Introducing preventive examinations in the regions of increased risk of testicular tumour may allow earlier diagnosis.

Polygenic susceptibility to testicular cancer: implications for personalised health care

BACKGROUND

The increasing incidence of testicular germ cell tumour (TGCT) combined with its strong heritable basis suggests that stratified screening for the early detection of TGCT may be clinically useful. We modelled the efficiency of such a personalised screening approach, based on genetic risk profiling in combination with other diagnostic tools.

METHODS

We compared the number of cases potentially detectable in the population under a number of screening models. The polygenic risk scoring (PRS) model was assumed to have a log-normal relative risk distribution across the 19 currently known TGCT susceptibility variants. The diagnostic performance of testicular biopsy and non-invasive semen analysis was also assessed, within a simulated combined screening programme.

RESULTS

The area under the curve for the TGCT PRS model was 0.72 with individuals in the top 1% of the PRS having a nine-fold increased TGCT risk compared with the population median. Results from population-screening simulations only achieved a maximal positive predictive value (PPV) of 60%, highlighting broader clinical factors that challenge such strategies, not least the rare nature of TGCT. In terms of future improvements, heritability estimates suggest that a significant number of additional genetic risk factors for TGCT remain to be discovered, identification of which would potentially yield improvement of the PPV to 80-90%.

CONCLUSIONS

While personalised screening models may offer enhanced TGCT risk discrimination, presently the case for population-level testing is not compelling. However, future advances, such as more routine generation of whole genome data is likely to alter the landscape. More targeted screening programs may plausibly then offer clinical benefit, particularly given the significant survivorship issues associated with the successful treatment of TGCT.

Whole-exome sequencing reveals the mutational spectrum of testicular germ cell tumours

Testicular germ cell tumours (TGCTs) are the most common cancer in young men. Here we perform whole-exome sequencing (WES) of 42 TGCTs to comprehensively study the cancer's mutational profile. The mutation rate is uniformly low in all of the tumours (mean 0.5 mutations per Mb) as compared with common cancers, consistent with the embryological origin of TGCT. In addition to expected copy number gain of chromosome 12p and mutation of KIT, we identify recurrent mutations in the tumour suppressor gene CDC27 (11.9%). Copy number analysis reveals recurring amplification of the spermatocyte development gene FSIP2 (15.3%) and a 0.4 Mb region at Xq28 (15.3%). Two treatment-refractory patients are shown to harbour XRCC2 mutations, a gene strongly implicated in defining cisplatin resistance. Our findings provide further insights into genes involved in the development and progression of TGCT.