Prostate and breast cancer in four Nordic countries: A comparison of incidence and mortality trends across countries and age groups 1975-2013.

In recent decades, management of prostate and breast cancer patients has changed considerably. The purpose of our study is to interpret patterns of prostate and breast cancer incidence and mortality in four Nordic countries across age groups and time periods. Prostate and breast cancer incidence and mortality data (1975-2013) were obtained from the NORDCAN database. Joinpoint regression models were used to identify changes in the trends. A more prominent increase in prostate than breast cancer incidence was observed. From the mid-1990s, mortality rates in patients below 75 years of age have decreased for both cancers in all four countries. The relative decline in breast cancer mortality from 1985-1989 to 2009-2013 were largest in women under 50 years of age, with reductions in mortality rates ranging from 38% in Finland to 55% in Denmark. In the age group 55-74 years, mortality rates for prostate cancer declined more than for breast cancer in all countries except Denmark, ranging from 14% in Denmark to 39% in Norway. The substantial decrease in breast cancer mortality in women below regular screening age and the reductions in mortality from both cancers in Denmark from the mid-1990s are consistent with beneficial contributions from improved treatment besides mammography screening and increased PSA testing. Alongside similar mortality decreases, the larger increases in prostate cancer incidence as compared to breast cancer indicate that a higher proportion of prostate cancer cases are overdiagnosed.

50 years of screening in the Nordic countries: quantifying the effects on cervical cancer incidence.

BACKGROUND: Nordic countries' data offer a unique possibility to evaluate the long-term benefit of cervical cancer screening in a context of increasing risk of human papillomavirus infection. METHODS: Ad hoc-refined age-period-cohort models were applied to the last 50-year incidence data from Denmark, Finland, Norway and Sweden to project expected cervical cancer cases in a no-screening scenario. RESULTS: In the absence of screening, projected incidence rates for 2006-2010 in Nordic countries would have been between 3 and 5 times higher than observed rates. Over 60,000 cases or between 41 and 49% of the expected cases of cervical cancer may have been prevented by the introduction of screening in the late 1960s and early 1970s. CONCLUSIONS: Our study suggests that screening programmes might have prevented a HPV-driven epidemic of cervical cancer in Nordic countries. According to extrapolations from cohort effects, cervical cancer incidence rates in the Nordic countries would have been otherwise comparable to the highest incidence rates currently detected in low-income countries.

Breast cancer survival and stage at diagnosis in Australia, Canada, Denmark, Norway, Sweden and the UK, 2000-2007: a population-based study.

BACKGROUND: We investigate whether differences in breast cancer survival in six high-income countries can be explained by differences in stage at diagnosis using routine data from population-based cancer registries. METHODS: We analysed the data on 257,362 women diagnosed with breast cancer during 2000-7 and registered in 13 population-based cancer registries in Australia, Canada, Denmark, Norway, Sweden and the UK. Flexible parametric hazard models were used to estimate net survival and the excess hazard of dying from breast cancer up to 3 years after diagnosis. RESULTS: Age-standardised 3-year net survival was 87-89% in the UK and Denmark, and 91-94% in the other four countries. Stage at diagnosis was relatively advanced in Denmark: only 30% of women had Tumour, Nodes, Metastasis (TNM) stage I disease, compared with 42-45% elsewhere. Women in the UK had low survival for TNM stage III-IV disease compared with other countries. CONCLUSION: International differences in breast cancer survival are partly explained by differences in stage at diagnosis, and partly by differences in stage-specific survival. Low overall survival arises if the stage distribution is adverse (e.g. Denmark) but stage-specific survival is normal; or if the stage distribution is typical but stage-specific survival is low (e.g. UK). International differences in staging diagnostics and stage-specific cancer therapies should be investigated.

A health economic evaluation of follow-up after breast cancer surgery: results of an rct study.

INTRODUCTION: Breast cancer follow-up programmes consume large resources and despite the indications that several alternative approaches could be used effectively, there is no coherent discussion about costs and/or cost-effectiveness of follow-up programmes. PATIENT AND METHODS: In a prospective trial there were 264 breast cancer patients, stage I and II, randomised to two different follow-up programmes- PG (physician group) and NG (nurse group). The trial period was 5 years. The women in the two intervention groups did not differ in anxiety and depression, their satisfaction with care, their experienced accessibility to the medical centre or their medical outcome as measured by recurrence or death. The analyses were done from different lists representing costs at three hospitals in Sweden according to the principles of a cost minimization study. RESULTS: The cost per person year of follow-up differed between the groups, with 630 euro per person year in PG compared to 495 euro per person year in NG. Thus, specialist nurse intervention with check-ups on demand was 20% less expensive than routine follow-up visits to the physician. The main difference in cost between the groups was explained by the numbers of visits to the physician in the respective study arms. There were 21% more primary contacts in PG than NG. DISCUSSION: The difference in cost per year and patient by study arm is modest, but transforms to nearly 900 euro per patient and 5-year period, offering a substantial opportunity for reallocating resources since breast cancer is the most prevalent tumour worldwide.

The 15-Country Collaborative Study of Cancer Risk among Radiation Workers in the Nuclear Industry: estimates of radiation-related cancer risks.

A 15-Country collaborative cohort study was conducted to provide direct estimates of cancer risk following protracted low doses of ionizing radiation. Analyses included 407,391 nuclear industry workers monitored individually for external radiation and 5.2 million person-years of follow-up. A significant association was seen between radiation dose and all-cause mortality [excess relative risk (ERR) 0.42 per Sv, 90% CI 0.07, 0.79; 18,993 deaths]. This was mainly attributable to a dose-related increase in all cancer mortality (ERR/Sv 0.97, 90% CI 0.28, 1.77; 5233 deaths). Among 31 specific types of malignancies studied, a significant association was found for lung cancer (ERR/Sv 1.86, 90% CI 0.49, 3.63; 1457 deaths) and a borderline significant (P = 0.06) association for multiple myeloma (ERR/Sv 6.15, 90% CI <0, 20.6; 83 deaths) and ill-defined and secondary cancers (ERR/Sv 1.96, 90% CI -0.26, 5.90; 328 deaths). Stratification on duration of employment had a large effect on the ERR/Sv, reflecting a strong healthy worker survivor effect in these cohorts. This is the largest analytical epidemiological study of the effects of low-dose protracted exposures to ionizing radiation to date. Further studies will be important to better assess the role of tobacco and other occupational exposures in our risk estimates.

Reduced mortality for women with mammography-detected breast cancer in east Denmark and south Sweden.

The 5-year relative survival from breast cancer in Denmark is 10 percentage points lower than in Sweden. This difference has been demonstrated previously as being caused partly by more involved lymph nodes and larger tumours in Denmark. Sweden has had nationwide mammography-screening coverage since 1991, whereas this is still in its infancy in Denmark. In the search for an explanation for the remaining survival difference, patient delay was a likely candidate. This study compared patient delay and mammography-detection between two national regions. Data on patient delay and mammography were obtained from hospital records from 1989 and 1994, and analysed using Cox proportional hazard analysis of death within the first 5 years, with the factors age, country, delay/mammography detection and established patho-anatomic variables. A comparison of patient delay and mammography detection in 1989 and 1994 showed more mammography-detected tumours in south Sweden and more women with long delay in east Denmark. Mammography detection, but not long patient delay, had a significant effect on the death hazard when adjusting for patho-anatomic risk factors. The hazard ratio was not eliminated in 1989, but in 1994, the hazard ratio between east Denmark and south Sweden was reduced from 1.3 to 1.1. In conclusion, patient delay did not appear to have any effect on 5-year survival when adjusting for patho-anatomic factors, but tumour detection by mammography affected survival favourably and partly explained the survival difference between east Denmark and south Sweden.

Uveal and conjunctival malignant melanoma in denmark 1943-97: observed and relative survival of patients followed through 2002.

PURPOSE: To evaluate the observed and relative survival of patients diagnosed with a malignant melanoma in the ocular region in Denmark during the period 1943-97. METHODS: The study included 2,504 patients (1,292 men and 1,212 women) diagnosed with a melanoma in the ocular region, of which 2,434 cases could be topographically subclassified into 2,178 in the choroid/ciliary body, 141 in the iris, and 115 in the conjunctiva. The patients were followed through 2002 and the observed survival proportions and relative survival ratios were estimated. RESULTS: For the total ocular region and the choroid/ciliary body, the observed survival did not vary statistically significantly with the year of diagnosis. A statistically insignificant higher observed survival for women than men was found for tumors in the ocular region and the subgroups choroid/ciliary body, iris, and conjunctiva. During the 55-year study period, the 5- and 10-year relative survival remained stable for the ocular region for men at 67% and 57% and for women at 71% and 60%, respectively, and stable for the choroid/ciliary body for men at 66% and 55% and for women at 69% and 57%, respectively. The 5- and 10-year relative survival for the iris was for men 90% and 85% and for women 99% and 101%, respectively, and for the conjunctiva for men 83% and 70% and for women 93% and 82%, respectively. CONCLUSION: The observed and relative survival of patients diagnosed with a melanoma in the ocular region and choroid/ciliary body in Denmark during the period 1943-97 and followed through 2002 has remained stable. The highest observed and relative survival was found for iris melanomas, the lowest for choroid/ciliary body melanomas, and intermediate for conjunctival melanomas.

Uveal and conjunctival malignant melanoma in Denmark, 1943-97: incidence and validation study.

PURPOSE: To study the incidence of malignant melanoma in the ocular region in Denmark during the period 1943-97. METHODS: The patients were mainly identified through the Danish Cancer Registry. Age-period-cohort modelling of the incidence rates was done based on age at diagnosis, calendar period and birth cohort in 5-year groups and for each gender. RESULTS: The age-standardized incidence of malignant melanoma in the ocular region was 0.78 for men (N = 1327) and 0.65 for women (N = 1242) per 100,000 person-years. Calendar period and birth cohort had no effect on the incidence in the ocular region or in the topography subgroups choroid/ciliary body and conjunctiva. However, the incidence increased with birth cohort for iris melanomas. CONCLUSIONS: The incidence of malignant melanoma in the ocular region was stable in contrast to a major increase in cutaneous melanoma in Denmark during the period 1943-97. The incidence of iris melanomas increased substantially, whereas the rate was stable for choroid/ciliary body and conjunctival melanomas.

Risk of cancer after low doses of ionising radiation: retrospective cohort study in 15 countries.

OBJECTIVES: To provide direct estimates of risk of cancer after protracted low doses of ionising radiation and to strengthen the scientific basis of radiation protection standards for environmental, occupational, and medical diagnostic exposures. DESIGN: Multinational retrospective cohort study of cancer mortality. SETTING: Cohorts of workers in the nuclear industry in 15 countries. PARTICIPANTS: 407 391 workers individually monitored for external radiation with a total follow-up of 5.2 million person years. MAIN OUTCOME MEASUREMENTS: Estimates of excess relative risks per sievert (Sv) of radiation dose for mortality from cancers other than leukaemia and from leukaemia excluding chronic lymphocytic leukaemia, the main causes of death considered by radiation protection authorities. RESULTS: The excess relative risk for cancers other than leukaemia was 0.97 per Sv, 95% confidence interval 0.14 to 1.97. Analyses of causes of death related or unrelated to smoking indicate that, although confounding by smoking may be present, it is unlikely to explain all of this increased risk. The excess relative risk for leukaemia excluding chronic lymphocytic leukaemia was 1.93 per Sv (< 0 to 8.47). On the basis of these estimates, 1-2% of deaths from cancer among workers in this cohort may be attributable to radiation. CONCLUSIONS: These estimates, from the largest study of nuclear workers ever conducted, are higher than, but statistically compatible with, the risk estimates used for current radiation protection standards. The results suggest that there is a small excess risk of cancer, even at the low doses and dose rates typically received by nuclear workers in this study.

Early life events and later risk of colorectal cancer: age-period-cohort modelling in the Nordic countries and Estonia.

BACKGROUND: A lowering of colorectal cancer risk for the birth cohorts born around World War II (WWII) has previously been observed in Norway, a country which suffered some 20% caloric restriction during the war. The purpose of the study was to conduct a similar kind of analysis in the other Nordic countries and Estonia, which were also subjected to various degrees of energy restriction during WWII. METHODS: All new cases of colorectal cancer in the Nordic countries and Estonia diagnosed between 40 and 84 years of age and born between 1874 and 1953, were collected from the national cancer registries. The incidence data were fitted to an age-period-cohort model. RESULTS: A transient drop in the estimated colorectal cancer incidence rate was observed for the birth cohorts born around WWII in Estonia, together with a tendency of decreased risk in Sweden and Denmark. CONCLUSION: The previously observed lowering of colorectal cancer risk for persons born during WWII in Norway also prevails in Estonia. Energy restriction is a possible explanation for these findings, since the countries suffered from varying nutritional conditions during the war. Exogenous factors acting during periods early in life may have an impact on later colorectal cancer risk.

Suicides among Danish cancer patients 1971-1999.

Compared to the general population, the suicide risk among Danish cancer patients diagnosed in 1971-1986 was increased by 50% for men and 30% for women. We updated the earlier study to evaluate both long-term and recent trends in the suicide risk. Cancer patients with a first cancer diagnosed between 1971 and 1999 in Denmark were followed-up for completed suicide through 1999. Excluding nonmelanoma skin cancer, 564 508 cancer patients were included and 1241 suicides observed. Both the standardised mortality ratio (SMR) of suicide relative to the general population and the suicide rates were analysed with Poisson regression methods. The overall SMR was increased to 1.7 (95% CI. 1.6-1.9) for men and 1.4 (95% CI: 1.3-1.5) for women. Following the cancer diagnosis, the suicide risk was highest in the first 3 months for men and between months 3 and 12 for women. The risk was higher for nonlocalized cancer and for cancers with perceived poor prognosis. Breast cancer patients had a higher risk than other cancer patients with similar good prognosis. The suicide rates among cancer patients decreased with calendar time, but less so than the rates in the general population. The suicide risk among cancer patients has not decreased as much as in the Danish population and reasons for this should be explored. Breast cancer might be believed by patients to be more life threatening than it is. Assessment and treatment of depression could improve the quality of life for cancer patients who suffer from unrecognised depressions and in turn reduce the risk of suicide in cancer patients.

Educational attainment among survivors of childhood cancer: a population-based cohort study in Denmark.

We identified 2384 patients in the Danish Cancer Register in whom cancer had been diagnosed in 1960-1996 before they reached the age of 20 and compared them with 53 143 sex- and age-matched controls identified from the Register of Population Statistics. Complete education records and demographic and socioeconomic information for the period 1980-2000 were obtained for both cohorts from Statistics Denmark. The rate ratio (RR) for educational attainment was estimated by discrete-time Cox regression analyses. An overall reduction in attaining basic education was found (RR, 0.90; 95% confidence interval, 0.83-0.96). Female survivors of central nervous system (CNS) tumours showed the largest educational deficit (RR, 0.55; 95% confidence interval, 0.37-0.82). Non-CNS tumour survivors attained education as controls at most levels. When the analyses were conditioned on completion of youth education, further educational attainment was not reduced for any group of survivors. These findings confirm that only survivors of CNS tumours in childhood experience significant educational deficits. The deficit was mainly seen among persons whose tumour was diagnosed before they reached the level of secondary education.

Nurse-led follow-up on demand or by a physician after breast cancer surgery: a randomised study.

The value of routine follow-up with frequent visits to a breast cancer specialist-both in terms of detection of recurrence and patient satisfaction-has been questioned. The aim of this study was to compare nurse-led follow-up on demand versus physician follow-up after breast cancer treatment with regards to patients' well-being, satisfaction, access to medical care and medical safety. Two hundred and sixty-four consecutively selected women with newly diagnosed breast cancer, classified as UICC stage I or stage II, were randomised to follow-up at two hospitals in Sweden, either by routine medical follow-up, the physician group (PG, n=131), or on demand by a specialist nurse, the nurse group (NG, n=133). Measures were done at baseline and twice a year over a period of 5 years by means of a questionnaire containing the Hospital Anxiety and Depression Scale (HAD), and the Satisfaction and Accessibility (SaaC) scale. Number of contacts with the health care services, number of diagnostic procedures, and time to recurrence or death were monitored. The ratings of HAD and SaaC did not show any statistically significant differences between the groups. The levels of anxiety and depression were generally low and levels of patient satisfaction high. There were no differences between the groups concerning time to recurrence or death. This study indicates that women with breast cancer in stages I to II can be followed up by a specialist nurse with high patient satisfaction and good medical safety.

Can the survival difference between breast cancer patients in Denmark and Sweden 1989 and 1994 be explained by patho-anatomical variables?--a population-based study.

Analyses of data from cancer registries have shown a 10% unit difference in 5-year relative survival between Danish and Swedish patients with breast cancer. This study investigates the effect of age and patho-anatomic variables on this survival difference. Hospital records were collected for women over 40 years of age diagnosed in 1989 or 1994 in east Denmark and south Sweden; patho-anatomical variables and survival were compared between 2289 Danish and 1715 Swedish women. Tumours were smaller, node-negative axillae more frequent and well-differentiated tumours almost 10% more frequent in Sweden. A superior 5-year relative survival in Sweden was found in the 50- to 79-year age group. The adjusted hazard rate ratio between countries was 1.7 in 1989 and 1.3 in 1994. Conditional survival after surviving the first 5 years was similar for the two countries. Adjusting for patho-anatomical variables reduced but did not eliminate the higher risk of death among the Danish patients. Higher population death rates could explain some but not all of the residual elevated risk for Danish women.

Update of the follow-up of mortality and cancer incidence among European workers employed in the vinyl chloride industry.

Although vinyl chloride is an established cause of liver angiosarcoma, the evidence is inconclusive on whether it also causes other neoplastic and nonneoplastic chronic liver diseases as well as neoplasms in other organs. Furthermore, the shape of the dose-response relation for angiosarcoma is uncertain. We have extended for approximately 8 years the mortality and cancer incidence follow-up of 12,700 male workers in the vinyl chloride industry in four European countries. All-cause mortality was lower than expected, whereas cancer mortality was close to expected. A total of 53 deaths from primary liver cancer (standardized mortality ratio 2.40, 95% confidence interval = 1.80-3.14) and 18 incident cases of liver cancer were identified, including 37 angiosarcomas, 10 hepatocellular carcinomas, and 24 liver cancers of other and unknown histology. In Poisson regression analyses we observed a marked exposure response for all liver cancers, angiosarcoma, and hepatocellular carcinoma. The exposure-response trend estimated for liver cancer in analyses restricted to cohort members with cumulative exposures of <1,500 parts per million-years was close to that estimated for the full cohort (relative risk of 2.0 per logarithmic unit of cumulative dose). No strong relation was observed between cumulative vinyl chloride exposure and other cancers. Although cirrhosis mortality was decreased overall, there was a trend with cumulative exposure.

Incident thromboembolism in the aorta and the renal, mesenteric, pelvic, and extremity arteries after discharge from the hospital with a diagnosis of atrial fibrillation.

BACKGROUND: The impact of atrial fibrillation (AF) on risk of peripheral arterial thromboembolism is unknown. METHODS: We analyzed the risk of thromboembolism (embolus and/or thrombosis) in the aorta and the renal, mesenteric, pelvic, and extremity arteries in a cohort of patients discharged from the hospital with an incident diagnosis of AF relative to the risk of thromboembolism in these vessels in the Danish population. In a random sample of half of the Danish population, 14 917 men and 14 945 women aged 50 to 89 years were identified in the Danish National Hospital Discharge Register with a diagnosis of AF from January 1, 1980, through December 31, 1993. Patients were followed up from diagnosis of AF in the Danish National Hospital Discharge Register and the Causes of Death Register until the first diagnosis of a thromboembolic event, death, or the end of 1993. Risk of a thromboembolic event relative to the risk in the Danish population was analyzed by means of Poisson regression modeling. RESULTS: Patients with a hospital diagnosis of AF had an increased risk of thromboembolic events in the aorta and the renal, mesenteric, pelvic, and extremity arteries (relative risk, 4.0 [95% confidence interval, 3.5-4.6] in men; and relative risk, 5.7 [95% confidence interval, 5.1-6.3] in women) compared with the Danish population. CONCLUSION: A hospital diagnosis of AF is an important risk factor for peripheral arterial thromboembolic complications.

Incident stroke after discharge from the hospital with a diagnosis of atrial fibrillation.

PURPOSE: Atrial fibrillation is an important risk factor for stroke. We analyzed stroke risk over time in patients discharged from the hospital with a diagnosis of incident atrial fibrillation as compared with the risk of stroke in the Danish population. SUBJECTS AND METHODS: In a random sample of half of the Danish population, we identified 13,625 men and 13,577 women, aged 50 to 89 years, with a hospital diagnosis of atrial fibrillation and no prior diagnosis of stroke during 1980 to 1993. Data on other medical conditions were also available from 1977 to 1993, but medication data were not available. Patients were followed from the diagnosis of atrial fibrillation until the first diagnosis of stroke (nonfatal or fatal cerebral ischemic infarct and cerebral hemorrhage), death, or the end of 1993. The risk of stroke in these patients was compared with the risk in the Danish population using Poisson regression modeling to estimate relative risks (RR) and 95% confidence intervals (CI). RESULTS: For men with atrial fibrillation, the stroke rates increased by age, from 13 per 1,000 person-years in those ages 50 to 59 years, to 22 per 1,000 person-years in those ages 60 to 69 years, to 42 per 1,000 person-years in those ages 70 to 79 years, to 51 per 1,000 person-years in those ages 80 to 89 years. Age-specific stroke rates were similar in women with atrial fibrillation. Patients with a hospital diagnosis of atrial fibrillation had an increased risk of stroke (RR = 2.4; 95% CI, 2.3 to 2.5 in men and RR = 3.0; 95% CI, 2.9 to 3.2 in women) compared with the Danish population. Stroke risk was greatest during the first year after discharge and decreased thereafter. Hypertension, diabetes, and peripheral atherosclerosis were also associated with an increased risk of stroke among patients with atrial fibrillation. Ischemic heart disease and heart failure were risk factors in men only. There was no reduction in the risk of stroke from 1980 to 1993. CONCLUSIONS: Men and women with atrial fibrillation are at a substantially increased risk of stroke, particularly in the first year after the diagnosis.

A discrepancy between gestational age estimated by last menstrual period and biparietal diameter may indicate an increased risk of fetal death and adverse pregnancy outcome.

OBJECTIVE: To determine if the discrepancy between gestational age estimated by last menstrual period and by biparietal diameter (GALMP - GABPD) is associated with adverse pregnancy outcome. DESIGN: Population-based follow up study. POPULATION: Singleton pregnancies were studied when a reliable date of last menstrual period and biparietal diameter measured between 12 and 22 weeks of gestation was available (n = 16,469). METHODS: Logistic regression analysis and Kaplan-Meier survival analysis were used to analyse the association between GALMP - GABPD and adverse pregnancy outcome. MAIN OUTCOME MEASURES: Adverse outcome was defined as abortion after 12 weeks of gestation, still-birth or postnatal death within one year of birth, delivery < 37 weeks of gestation, a birthweight < 2,500 g or a sex-specific birthweight lower than 22% below the expected. RESULTS: The risk of death was more than doubled if GALMP - GABPD of > or = 8 days was compared with GALMP - GABPD of < 8 days (OR 2.2; 95% CI 1.6-3.1). The risk of death was a factor of 6.1 higher if GALMP - GABPD of > or = 8 days was combined with increased (> 2 x multiple of median) maternal alpha-fetoprotein measured in the 2nd trimester. CONCLUSIONS: A discrepancy between GALMP and GABPD generally reflects the precision of the two methods used to predict term pregnancy. However, a positive discrepancy of more than seven days, particularly with high maternal alpha-fetoprotein, might indicate intrauterine growth retardation and an increased risk of adverse perinatal outcome.

Risk of testicular cancer in men with abnormal semen characteristics: cohort study.

OBJECTIVE: To explore the associations between semen characteristics and subsequent risk of testicular cancer. DESIGN: Cohort study. PARTICIPANTS: 32 442 men who had a semen analysis done at the Sperm Analysis Laboratory in Copenhagen during 1963-95. MAIN OUTCOME MEASURE: Standardised incidence ratios of testicular cancer compared with total population of Danish men. RESULTS: Men in couples with fertility problems were more likely to develop testicular cancer than other men (89 cases, standardised incidence ratio 1.6; 95% confidence interval 1.3 to 1.9). The risk was relatively constant with increasing time between semen analysis and cancer diagnosis. Analysis according to specific semen characteristics showed that low semen concentration (standardised incidence ratio 2.3), poor motility of the spermatozoa (2.5), and high proportion of morphologically abnormal spermatozoa (3.0) were all associated with an increased risk of testicular cancer. The only other cancer group that showed increased incidence was "peritoneum and other digestive organs" (six cases; 3.7, 1.3 to 8.0). Of these, two cases were probably and two cases were possibly extragonadal germ cell tumours. CONCLUSIONS: The results point towards the existence of common aetiological factors for low semen quality and testicular cancer. Low semen quality may also be associated with increased incidence of extragonadal germ cell tumours.