Occupational risk factors for testicular cancer: a registry-based case-control study in Rhineland Palatinate-Germany

A Survey on the Knowledge and Awareness of Testicular Cancer and Testicular Self-Examination Among Men in Saudi Arabia

Objectives The aim of the study was to assess the knowledge and awareness of testicular cancer (TC) and testicular self-examination (TSE) and to identify the associated factors in men in Saudi Arabia. Methods An online questionnaire-based study was conducted in Saudi Arabia with a representative sample of 794 participants. The questionnaire comprised knowledge, awareness and attitude questions regarding TC and TSE in addition to signs/symptoms and risk factors. Multivariate logistic regression analysis was conducted to identify the significant variables associated with knowledge of TC and TSE. Results Around 43% (n=340) of the participants had inadequate knowledge of TC, whereas 26% (n=205) had heard about TSE and only 65 (8.2%) performed TSE. The first model for knowledge found that participants with a low level of education [2.75 (1.18, 6.42)]; no past history of a testicular problem [2.20 (1.22, 3.95)] and those who had not heard about TSE [1.79 (1.24, 2.57)] were at higher odds for inadequate knowledge, whereas those whose mothers had received college-level education [0.39 (0.19, 0.79)] and those who received information from school/college [0.61 (0.37, 0.97)] were more likely to have adequate knowledge about TC. The second model for TSE found that a low level of education 5.24 (1.34, 20.52) was associated with not performing TSE. Receiving information from social media [0.08 (0.03, 0.17)], school/college [0.06 (0.02, 0.13)], family and friends [0.17 (0.05, 0.57)] and medical staff [0.08 (0.03, 0.17)] were associated with higher odds of performing TSE. Conclusion The majority of Saudi males have knowledge about TC. On the contrary, only a small percentage of the respondents have heard of or performed TSE as a screening technique. Educated sources of information can be a reliable way of giving correct knowledge on sensitive topics like TSE.

Childhood hematologic cancer and residential proximity to oil and gas development

Background

Oil and gas development emits known hematological carcinogens, such as benzene, and increasingly occurs in residential areas. We explored whether residential proximity to oil and gas development was associated with risk for hematologic cancers using a registry-based case-control study design.

Methods

Participants were 0–24 years old, living in rural Colorado, and diagnosed with cancer between 2001–2013. For each child in our study, we calculated inverse distance weighted (IDW) oil and gas well counts within a 16.1-kilometer radius of residence at cancer diagnosis for each year in a 10 year latency period to estimate density of oil and gas development. Logistic regression, adjusted for age, race, gender, income, and elevation was used to estimate associations across IDW well count tertiles for 87 acute lymphocytic leukemia (ALL) cases and 50 non-Hodgkin lymphoma (NHL) cases, compared to 528 controls with non-hematologic cancers.

Findings

Overall, ALL cases 0–24 years old were more likely to live in the highest IDW well count tertiles compared to controls, but findings differed substantially by age. For ages 5–24, ALL cases were 4.3 times as likely to live in the highest tertile, compared to controls (95% CI: 1.1 to 16), with a monotonic increase in risk across tertiles (trend p-value = 0.035). Further adjustment for year of diagnosis increased the association. No association was found between ALL for children aged 0–4 years or NHL and IDW well counts. While our study benefited from the ability to select cases and controls from the same population, use of cancer-controls, the limited number of ALL and NHL cases, and aggregation of ages into five year ranges, may have biased our associations toward the null. In addition, absence of information on O&G well activities, meteorology, and topography likely reduced temporal and spatial specificity in IDW well counts.

Conclusion

Because oil and gas development has potential to expose a large population to known hematologic carcinogens, further study is clearly needed to substantiate both our positive and negative findings. Future studies should incorporate information on oil and gas development activities and production levels, as well as levels of specific pollutants of interest (e.g. benzene) near homes, schools, and day care centers; provide age-specific residential histories; compare cases to controls without cancer; and address other potential confounders, and environmental stressors.

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.