The epidemiology of non-seminomatous germ cell tumours in the west of Scotland 1975-89

Incidence of testicular germ cell tumors among US men by census region

BACKGROUND

The incidence of testicular germ cell tumors (TGCTs) in the United States is notably higher among white men versus other men. Previously, however, it was reported that rates were rising among Hispanics in certain areas. To determine whether this finding was evident in a wider area of the United States, data from 39 US cancer registries were examined.

METHODS

Racial/ethnic-specific incidence rates per 100,000 man-years were calculated overall and by census region for the period of 1998-2011. Annual percentage changes (APCs) were estimated, and joinpoint models were fit. Differences in incidence by region were examined with the Wald test.

RESULTS

From 1998 to 2011, 88,993 TGCTs were recorded. The TGCT incidence was highest among non-Hispanic whites (6.57 per 100,000), who were followed by Hispanics (3.88), American Indians/Alaska Natives (2.88), Asians/Pacific Islanders (A/PIs; 1.60), and non-Hispanic blacks (1.20). The incidence significantly increased among Hispanics (APC, 2.31; P < .0001), with rates rising in all regions except the South. Rates rose slightly among non-Hispanic whites (APC, 0.51; P = .0076). Significant differences in rates by region were seen for Hispanics (P = .0001), non-Hispanic whites (P < .0001), and A/PIs (P < .0001), with the highest rates among Hispanics in the West and with the highest rates among non-Hispanic whites and A/PIs in the Northeast.

CONCLUSIONS

Although the incidence of TGCTs remained highest among non-Hispanic whites between 1998 and 2011, the greatest increase was experienced by Hispanics. Rising rates of TGCTs among Hispanics in the United States suggest that future attention is warranted. Reasons for the increase may include variability in birthplace, changing exposures, genetic susceptibility, and the length of US residence.

Testicular cancer: a narrative review of the role of socioeconomic position from risk to survivorship

BACKGROUND

Testicular cancer (TC) is one of the most curable cancers. Given survival rates of close to 100% with appropriate therapy, ensuring proper treatment is essential. We reviewed and summarized the literature on the association of socioeconomic position (SEP) along the cancer control spectrum from risk factors to survivorship.

METHODS

We searched PubMed from 1966 to 2011 using the following terms: testicular cancer, testicular neoplasm, poverty, and socioeconomic factors, retrieving 119 papers. After excluding papers for the non-English (10) language and non-relevance (46), we reviewed 63 papers. We abstracted information on socioeconomic position (SEP), including occupation, education, income, and combinations of the 3. Five areas were examined: risk factors, diagnosis, treatment, survival, and survivorship.

RESULTS

Most studies examined area-based measures, not individual measures of SEP. The majority of studies found an increased risk of developing TC with high SEP though recent papers have indicated increased risk in low-income populations. Regarding diagnosis, recent papers have indicated that lower levels of education and SEP are risk factors for later-stage TC diagnosis and hence higher TC mortality. For treatment, 1 study that examined the use of radiation therapy (RT) in stage I seminoma reported that living in a county with lower educational attainment led to lower use of RT. For survival (mortality), several studies found that men living in lower SEP geographic areas experience lower survival and higher mortality.

CONCLUSION

The strongest evidence for SEP impact on testicular germ cell tumor (TGCT) was found for the risk of developing cancer as well as survival. The association of SEP with TGCT risk appears to have changed over the last decade. Given the highly curable nature of TGCT, more research is needed to understand how SEP impacts diagnosis and treatment for TGCT and to design interventions to address disparities in TGCT outcomes and SEP.

Ethnic and socioeconomic trends in testicular cancer incidence in New Zealand

Ethnic differences in testicular cancer incidence within countries are often sizeable, with white populations consistently having the highest ethnic-specific rates. Many studies have found that high socioeconomic status is a risk factor for testicular cancer. The objectives of this article are to test whether trends in testicular cancer incidence have varied by ethnicity and socioeconomic position in New Zealand between 1981 and 2004. Five cohorts of the entire New Zealand population for 1981-1986, 1986-1991, 1991-1996, 1996-2001 and 2001-2004 were created, and probabilistically linked to cancer registry records, allowing direct determination of ethnic and household income trends in testicular cancer incidence. There were more than 2,000 cases of testicular cancer over the study period. We found increasing rates of testicular cancer for all ethnic and income groups since 1990s. Maori had higher rates, and Pacific and Asian lower rates than European/other men with rate ratios pooled over time of 1.51 (95% CI 1.31-1.74), 0.40 (95% CI 0.26-0.61) and 0.54 (95% CI 0.31-0.94), respectively. Overall, men with low incomes had higher risk of testicular cancer than those with high incomes (pooled rate ratio for lowest to highest income groups = 1.23; 95% CI 1.05-1.44). There was no strong evidence that disparities in testicular cancer incidence have varied by ethnicity or household income over time. Given the lack of understanding of the etiology of testicular cancer, the unusual patterns identified in the New Zealand context may provide some etiological clues for future novel research.

Testicular Cancer Variations in Time and Space in Europe

OBJECTIVES

Testicular cancer (TC) is the most common malignancy in young men. A review of all published articles on TC incidence revealed an increased incidence in Northern and Central Europe. We extended the analysis to the whole of Europe by using all data available, notably from registries.

METHODS

We performed a PubMed search and selected articles dealing with TC incidence. We obtained additional information from data of European registries through the eight volumes of the Cancer Incidence in Five Continents, IARC Scientific Publications.

RESULTS

Since the Second World War, TC incidence has been increasing in nearly all European countries. It has doubled in several countries, including France, since 1970. We observed that the increase followed a gradient: the highest rate is centred in Denmark and Germany, and decreases progressively in a centrifugal manner.

CONCLUSIONS

TC incidence is increasing throughout Europe, but wide discrepancies exist between the different countries. The reasons for such a phenomenon are still unclear although environmental factors are strongly suspected, which could have an impact on male fertility. From a public health perspective, further research using cases collected through national and regional population-based registers and case-control studies must be strongly encouraged.

Clinical epidemiology of testicular germ cell tumors

Clinical epidemiology is sometimes called the basic science of clinical medicine. In terms of the pathogenesis of testicular germ cell tumors (GCTs), clinical epidemiology analyzes suspected risk factors. The present review highlights the risk factors established so far and briefly summarizes those factors currently under investigation. In analogy to the methods of evidence based medicine, this review attributes levels of evidence to each of the putative risk factors. Level I represents highest quality of evidence while level V denotes the lowest level. So far, undescended testis (UDT), contralateral testicular GCT and familial testis cancer are established risk factors attaining high levels of evidence (levels I-III a). In a meta-analysis of 21 studies exploring the association of UDT with GCT risk, an over-all relative risk (RR) of 4.8 (95% confidence interval 4.0-5.7) was found. Contralateral testicular GCT involves a roughly 25-fold increased RR of GCT, while familial testis cancer constitutes a RR of 3-10. Infertility, testicular atrophy, and twin-ship represent risk factors with lesser levels of evidence (level III a). There is also some evidence for HIV infection being a predisposing factor for GCT (level IV a). Scrotal trauma is probably not associated with GCT risk. The estrogen excess theory implies high estrogen levels during the first trimester of pregnancy. As a consequence, primordial germ cells lose track of the normal developmental line and transform into premalignant cells that later become testicular intraepithelial neoplasia (TIN), the precursor of full-blown testicular GCT. Surrogate parameters for high gestational estrogen levels are investigated in case control studies. Such factors are maternal age >30 years, first-born, low birth weight, maternal breast cancer, high sex-ratio of siblings. So far, the sum of evidence is promising but still conflicting (especially for level III b). Another novel theory is the childhood nutrition hypothesis. This concept postulates a modulating or "catalyzing" effect by high dietary intake during childhood on the pathogenesis of testicular GCT. A surrogate parameter of early childhood nutrition is adult height. So far, 12 controlled studies have looked to the possible association of attained height and GCT risk of which six demonstrated a significant association. Thus, the sum of evidence corresponds to level III b. This concept is appealing because it would explain several hitherto unexplained epidemiological features of GCT.

Increasing incidence of testicular cancer worldwide: a review

PURPOSE

Testicular cancer (TC) is the most common malignancy in 20 to 34-year-old men. Numerous publications have shown an increase in the incidence of testis cancer in the last 40 years with substantial differences among countries. We evaluated worldwide variations in testicular cancer incidence and compared trends in different regions in the world.

MATERIALS AND METHODS

We reviewed 441 studies provided by a MEDLINE search using the key words testis/testicular, cancer/tumor and incidence that were published between 1980 and 2002. From these articles we selected only those devoted to testis cancer incidence and of them only the most recent studies from each country or region. Nevertheless, articles using the same data base but providing new and additional information, for example differences among ethnic groups or controversial explanations for trends, were also retained. We selected 30 articles and analyzed their methodological approach and main results.

RESULTS

Worldwide we observed a clear trend toward an increased TC incidence in the last 30 years in the majority of industrialized countries in North America, Europe and Oceania. Nevertheless, surprising differences in incidence rates were seen between neighboring countries (Finland 2.5/100,000 cases versus Denmark 9.2/100,000) as well as among regions of the same country (2.8 to 7.9/100,000 according to various regional French registers). In addition, substantial differences in the TC incidence and trends were observed among ethnic groups. The increase in the TC incidence was significantly associated with a birth cohort effect in the United States and in European countries. To date except for cryptorchidism no evident TC risk factor has been clearly demonstrated, although the environmental hypothesis with a key role of endocrine disrupters has been put forward by several groups.

CONCLUSIONS

Such a recent increase in the TC rate in most industrialized countries should lead urologists and andrologists to give more attention to testicular cancer symptoms in adolescents and young adults. In a public health perspective further research using cases collected through national and regional population based registers and case-control studies must be strongly encouraged if we wish to be able to assess future trends in TC incidence rates and also identify risk factors.

Sexual dysfunction after treatment for testicular cancer: a systematic review

OBJECTIVES

We aimed to assess the nature and risk of sexual dysfunction in men after treatment for testicular cancer.

METHOD

Systematic review of sexual dysfunction in men treated for testicular cancer. The odds ratio or proportions of subjects with reduced sexual drive, erectile dysfunction or orgasmic/ejaculatory dysfunction was calculated.

RESULTS

A detailed review of 79 of the 227 citations was conducted. The highest level of evidence found, were controlled studies. Six controlled studies examined sexual function in 709 patients after they had received treatment. Seven uncontrolled studies examined sexual function in 337 subjects before and after treatment for testicular cancer. Most studies were limited by low response rates, use of unvalidated questionnaires and inclusion of a variety of treatment modalities. Few assessed psychological function and none examined its possible interaction with sexual dysfunction. Meta-analysis of the controlled studies indicated significantly reduced or absent orgasm (OR=4.62, 95% CI=2.47-8.63) together with erectile (OR=2.47, 95% CI=1.54-3.96) and ejaculatory dysfunction (OR=28.57, 95% CI=1.75-464.78) up to 2 years after treatment. Effects on sexual function were less consistent in the uncontrolled studies.

CONCLUSIONS

The controlled studies indicate that sexual dysfunction persists for up to 2 years after treatment. However, better evidence is needed in studies that control for the impact of the testicular cancer, the treatment modality and psychological reactions to both.

Teratomas in infancy and childhood

BACKGROUND AND PROCEDURE

Outcomes in children with teratomas collected between October 1982 and December 1995 in cooperative protocols of the German Society of Pediatric Oncology and Hematology (GPOH) were analyzed. Teratomas were diagnosed in 329 (42%) of 780 registered patients with germ cell tumors. The annual incidence was 0.24/100,000. Main primary sites were coccygeal (n = 132, 2.2:1 female predominance), ovary (n = 81), testis (n = 40) and brain (n = 15, 2.8:1 male predominance).

RESULTS

Two hundred seventy cases of extracranial non-testicular teratoma were evaluated: In mature teratomas (n = 154) the observed relapse rate was 10%. Incomplete resection was the main risk factor for relapse. After complete resection, the relapse-free survival (RFS, Kaplan-Meier-estimation) was 0.96 +/- 0.01 (n = 126, observation time 18-155 months) in comparison to an RFS of 0.56 +/- 0.09 in incompletely resected teratomas grade 0 (n = 28, observation time 28-94 months) (P < 0.01). Im-mature teratomas were treated by surgery alone in 76 cases and by surgery and adjuvant chemotherapy in 40 cases. The observed relapse risk was 18%. Main risk factors for relapse were incomplete tumor resection (n = 38) as well as immaturity in incompletely resected teratomas. Fifteen of 29 relapsing patients presented with malignant tissue in the recurrent tumor (mainly yolk sac tumor); in contrast, seven of 40 patients with immature teratoma relapsed despite adjuvant chemotherapy without showing malignant components (P = 0.014). Nine of 36 (25%) relapsing patients died of disease. Eleven of the 27 (41%) surviving children suffered from mutilation after repeated surgery.

COMMENTS

It is suggested that an international randomized trial for patients with incompletely resected high risk teratoma be initiated to evaluate the effect of adjuvant chemotherapy on specific end-points: 1) influence on relapse rate in general; 2) reduction of the proportion of malignant relapses; 3) avoidance of mutilating surgery.

Alterations of the metastasis suppressor gene nm23 and the proto-oncogene c-myc in human testicular germ cell tumors

The putative metastasis suppressor genes nm23-H1, nm23-H2 and the c-myc proto-oncogene were investigated in testicular germ cell tumors (GCTs) using Southern and Northern blotting as well as semiquantitative reverse transcription polymerase chain reaction (RT-PCR) and single strand conformation polymorphism (SSCP) analysis. When studying Bgl II RFLPs, allelic losses of the nm23 gene were found in 3/12 (25%) informative tumors, and all 3 had lymph node and/or distant metastases. A 2 to 7 fold nm23 mRNA overexpression was found in 22/34 (64.7%) tumors examined. RT-PCR revealed that this phenomenon is mainly a consequence of nm23-H2 overexpression. Overexpression of both the H1 and the H2 gene was predominantly found in the seminoma subtype and was not associated with tumor stage. Only 1/25 tumors, a seminoma with distant metastases, had a point mutation in the coding region of the nm23-H2 gene as demonstrated by SSCP analysis. None of the 8 seminomas and only 1/13 non-seminomas had c-myc overexpression. No abnormalities of the c-myc gene could be detected on the DNA level. Despite the fact that in previous investigations nm23-H2 was demonstrated to be a putative transcription factor for c-myc, no coexpression of c-myc and nm23-H2 was found by quantitative RT-PCR in this study.

Current concepts about testicular cancer

In the past 20 years, testicular cancer, which occurs in the young, has become a curable malignancy; 90% of the patients treated will achieve long-term survival. However, there is a significant morbidity associated with the management of the disease process. The literature was reviewed concerning the current treatment strategies and prognosis, as well as the long-term sequelae of the various diagnostic and therapeutic procedures. Surveillance has become a key element in the management of patients with a primary (stage I) testicular non-seminoma. Although approximately 25% of these patients will relapse, 100% survival can be achieved with cisplatin in combination with etoposide and bleomycin (BEP). Patients with a disseminated non-seminoma are usually treated with 4 courses of BEP; an 80% survival rate can be achieved. The long-term effects of chemotherapy include Raynaud's phenomenon, acral paraesthesia, hyperlipidaemia, nephrotoxicity, infertility and hormonal disturbances. Retroperitoneal lymph node dissection or resection of residual disease following chemotherapy are associated with a low mortality and morbidity rate, ejaculatory dysfunction excepted. However, with specific modifications in technique (e.g. nerve-sparing) antegrade ejaculation can be preserved in the majority of patients. Radiotherapy is used in stage I and II seminoma. With the conventional dose of 25-30 Gy to the retroperitoneal and ipsilateral iliac lymph nodes, temporary dysfunction of the germ and Leydig cells of the remaining testis may occur by scatter radiation. Patients with advanced seminoma are treated with cisplatin-based chemotherapy. To date, testicular cancer patients can receive appropriate curative treatment with acceptable acute toxicity, depending on the therapy given. The detrimental effects of late toxicities require careful study and follow-up. However, little attention is paid currently to quality of life aspects, in particular the impact of the disease and its treatment on general well-being, including sexual function.