Cancer incidence in northern Sweden before and after the Chernobyl nuclear power plant accident

Sweden received about 5 % of the total release of ¹³⁷Cs from the Chernobyl nuclear power plant accident in 1986. The distribution of the fallout mainly affected northern Sweden, where some parts of the population could have received an estimated annual effective dose of 1–2 mSv per year. It is disputed whether an increased incidence of cancer can be detected in epidemiological studies after the Chernobyl nuclear power plant accident outside the former Union of Soviet Socialist Republics. In the present paper, a possible exposure–response pattern between deposition of ¹³⁷Cs and cancer incidence after the Chernobyl nuclear power plant accident was investigated in the nine northernmost counties of Sweden (2.2 million inhabitants in 1986). The activity of ¹³⁷Cs from the fallout maps at 1986 was used as a proxy for the received dose of ionizing radiation. Diagnoses of cancer (ICD-7 code 140-209) from 1980 to 2009 were received from the Swedish Cancer Registry (273,222 cases). Age-adjusted incidence rate ratios, stratified by gender, were calculated with Poisson regression in two closed cohorts of the population in the nine counties 1980 and 1986, respectively. The follow-up periods were 1980–1985 and 1986–2009, respectively. The average surface-weighted deposition of ¹³⁷Cs at three geographical levels; county (n = 9), municipality (n = 95) and parish level (n = 612) was applied for the two cohorts to study the pre- and the post-Chernobyl periods separately. To analyze time trends, the age-standardized total cancer incidence was calculated for the general Swedish population and the population in the nine counties. Joinpoint regression was used to compare the average annual percent change in the general population and the study population within each gender. No obvious exposure–response pattern was seen in the age-adjusted total cancer incidence rate ratios. A spurious association between fallout and cancer incidence was present, where areas with the lowest incidence of cancer before the accident coincidentally had the lowest fallout of ¹³⁷Cs. Increasing the geographical resolution of exposure from nine county averages to 612 parish averages resulted in a two to three times higher value of variance in the regression model. There was a secular trend with an increase in age-standardized incidence of cancer in both genders from 1980 to 2009, but significant only in females. This trend was stronger and statistically significant for both genders in the general Swedish population compared to the nine counties. In conclusion, using both high quality cancer registry data and high resolution exposure maps of ¹³⁷Cs deposition, it was not possible to distinguish an effect of ¹³⁷Cs on cancer incidence after the Chernobyl nuclear power plant accident in Sweden.     

Recent changes in endometrial cancer trends among menopausal-age US women

BackgroundChanges in endometrial cancer incidence rates after the precipitous decline in menopausal hormone therapy (MHT) use in 2002 have not been evaluated.MethodsUsing data from the Surveillance, Epidemiology, and End Results Program from 1992 to 2009 (SEER 13), we identified 63 428 incident endometrial cancer cases among women ages 20–74. We compared annual percent change (APC) in endometrial cancer incidence rates from 1992 to 2002 to rates from 2003 to 2009.ResultsIn contrast to the constant endometrial cancer rate pattern observed from 1992 to 2002 (APC 0.0%), rates increased after 2002 in women 50–74 years old (2.5%; P_{APC comparison} < 0.01). Endometrial cancer incidence increased over the entire time period among women ages 20–49 (1992–2002: 1.1%; 2003–2009: 2.1%; P_{APC comparison} = 0.21). Post-2002 increases in incidence among women ages 50–74 were specific to Type I endometrial tumors (1992–2002: ?0.6%; 2003–2009: 1.6%; P_{APC comparison} < 0.01).DiscussionThe increase in endometrial cancer incidence rates after 2002 may be related to the widespread decrease in estrogen plus progestin MHT use, which has been reported to lower endometrial cancer risk in overweight and obese women.     

Monte Carlo study on the secondary cancer risk estimations for patients undergoing prostate radiotherapy: A humanoid phantom study

AimThe aim of this study was to estimate the secondary malignancy risk from the radiation in FFB prostate linac-based radiotherapy for different organs of the patient.BackgroundRadiation therapy is one of the main procedures of cancer treatment. However, the application the radiation may impose dose to organs of the patient which can be the cause of some malignancies.Materials and methodsMonte Carlo (MC) simulation was used to calculate radiation doses to patient organs in 18 MV linear accelerator (linac) based radiotherapy. A humanoid MC phantom was used to calculate the equivalent dose s for different organs and probability of secondary cancer, fatal and nonfatal risk, and other risks and parameters related to megavoltage radiation therapy. In out-of-field radiation calculation, it could be seen that neutrons imparted a higher dose to distant organs, and the dose to surrounding organs was mainly due to absorbed scattered photons and electron contamination.ResultsOur results showed that the bladder and skin with 54.89 × 10⁻³ mSv/Gy and 46.09 × 10⁻³ mSv/Gy, respectively, absorbed the highest equivalent dose s from photoneutrons, while a lower dose was absorbed by the lung at 3.42 × 10⁻³ mSv/Gy. The large intestine and bladder absorbed 55.00 × 10⁻³ mSv/Gy and 49.08 × 10⁻³, respectively, which were the highest equivalent dose s due to photons. The brain absorbed the lowest out-of-field dose, at 1.87 × 10⁻³ mSv/Gy.ConclusionsWe concluded that secondary neutron portion was higher than other radiation. Then, we recommended more attention to neutrons in the radiation protection in linac based high energy radiotherapy.     

Radiological protection for pregnant women at a large academic medical Cancer Center

PurposeMost radiation protection programs, regulations and guidance apply specific restrictions to the occupational exposure of pregnant workers. The aim of this study was to compile data from the declared pregnant woman (DPW) radiation protection program over more than 5 years at a large, high-volume, comprehensive oncology academic/medical institution and to evaluate for effectiveness against existing regulations and guidance.MethodsA retrospective review was performed of the data collected as part of the DPW radiation protection program from January 2010 through May 2016, including the number of declared pregnancies, worker category, personal and fetal dosimetry monitoring measurements, workplace modifications, as well as the monthly and total recorded badge results during the entire pregnancy.Results245 pregnancies were declared. The mean monthly fetal radiation dosimetry result was 0.009 mSv with a median of 0.005 mSv and a maximum of 0.39 mSv. The mean total dose over the entire pregnancy was estimated to be 0.08 mSv with a median of 0.05 mSv and a maximum of 0.89 mSv. Only 8 (3.2%) of the 245 declared pregnancies required that workplace modifications be implemented for the worker.ConclusionsThe implementation of a declared pregnancy and fetal assessment program, careful planning, an understanding of the risks, and minimization of radiation dose by employing appropriate radiation safety measures as needed, can allow medical staff to perform procedures and normal activities without incurring significant risks to the conceptus, or significant interruptions of job activities for most medical workers.     

Acute myeloid leukemia incidence following radiation therapy for localized or locally advanced prostate adenocarcinoma

Introduction: The effect of radiation therapy on acute myeloid leukemia incidence among prostate cancer patients has not been sufficiently elucidated despite evidence that acute myeloid leukemia is a consequence of therapeutic radiation in other primary malignancies. Therefore, we investigated the effect of definitive therapy with radiation therapy (external beam radiation therapy [EBRT] or brachytherapy) on acute myeloid leukemia incidence in a population-based cohort of patients with localized or locally advanced prostate cancer. Methods: We utilized the Surveillance, Epidemiology, and End Results database to identify a cohort of men (n = 168,612) with newly diagnosed prostate adenocarcinoma between January 1988 and December 2003. Cox proportional hazard regression was used to estimate the hazard ratios (HRs) and corresponding 95% confidence intervals (CIs) of acute myeloid leukemia incidence following definitive therapy with EBRT alone, brachytherapy alone, or surgery alone compared to no definitive therapy (i.e. no EBRT, brachytherapy, or surgery). Results: The cohort yielded 184 acute myeloid leukemia cases during 1,064,820 person-years of follow-up after prostate adenocarcinoma diagnosis. Patients treated with EBRT had a higher adjusted relative risk of developing acute myeloid leukemia than patients treated with brachytherapy or surgery when each therapy group was compared to patients who were not treated with definitive therapy (EBRT: HR = 2.05, 95% CI 1.29, 3.26; brachytherapy: HR = 1.22, 95% CI 0.46, 3.22; surgery: HR = 1.24, 95% CI 0.77, 1.98). Conclusions: Our findings suggest that acute myeloid leukemia incidence is a greater concern for patients treated with EBRT than brachytherapy for localized or locally advanced prostate adenocarcinoma.     

Association between ultraviolet radiation,skin sun sensitivity and risk of pancreatic cancer

Background: Ecological studies showing an inverse association between pancreatic cancer incidence and mortality and levels of ultraviolet radiation (UVR), suggest that higher levels of sun exposure may reduce risks of pancreatic cancer but there has been only one individual-level study that examined this issue. We aimed to examine the association between pancreatic cancer and markers of exposure to solar UVR, namely skin type, treatment of skin lesions, ambient UVR and time outdoors on work days. Methods: We used data from an Australian case-control study. Location at birth, residential location during adulthood, outdoors work, history of skin lesion treatment and sensitivity of the skin to the sun were obtained by questionnaire. We limited the analyses to Caucasians who answered the questionnaire about UVR (controls = 589/711 recruited; cases = 496/705 recruited). We used NASA's Total Ozone Mapping Spectrometer to estimate ambient UVR. Results: Being born in or living in areas of higher ambient UVR (compared to lower ambient UVR) was associated with about 30–40% lower risk of pancreatic cancer. People with fair skin colour had 47% lower risk of pancreatic cancer than those with dark skin colour (95% CI 0.37–0.75). There was some suggestion of increased risk with increased average number of hours spent outside at work. Conclusions: This study suggests that people with light skin colour or those born or living in areas of high ambient UVR have lower risk of pancreatic cancer. Our analysis supports an association between UVR and pancreatic cancer, possibly mediated through production of vitamin D.     

Incidence,survival and mortality rates of stage-specific bladder cancer in United States: A trend analysis

PurposeTo examine the overall and stage-specific age-adjusted incidence, 5-year survival and mortality rates of bladder cancer (BCa) in the United States, between 1973 and 2009.Materials and methodsA total of 148,315 BCa patients were identified in the Surveillance, Epidemiology and End Results database, between years 1973 and 2009. Incidence, mortality, and 5-year cancer-specific survival rates were calculated. Temporal trends were quantified using the estimated annual percentage change (EAPC) and linear regression models. All analyses were stratified according to disease stage, and further examined according to sex, race, and age groups.ResultsIncidence rate of BCa increased from 21.0 to 25.5/100,000 person-years between 1973 and 2009. Stage-specific analyses revealed an increase incidence for localized stage: 15.4–20.2 (EAPC: +0.5%, p < 0.001) and distant stage: 0.5–0.8 (EAPC: +0.7%, p = 0.001). Stage-specific 5-year survival rates increased for all stages, except for distant disease. No significant changes in mortality were recorded among localized (EAPC: ?0.2%, p = 0.1) and regional stage (EAPC: ?0.1%, p = 0.5). An increase in mortality rates was observed among distant stage (EAPC: +1.0%, p = 0.005). Significant variations in incidence and mortality were recorded when estimates were stratified according to sex, race, and age groups.DiscussionAlbeit statistically significant, virtually all changes in incidence and mortality were minor, and hardly of any clinical importance. Little or no change in BCa cancer control outcomes has been achieved during the study period.     

Examining the association between cigarette smoking and colorectal cancer using historical case–control data

Background: The majority of recent, well-designed studies have shown that long-term cigarette smoking increases colorectal cancer risk, but older studies with shorter durations of exposure often found no association. This study aimed to examine colorectal cancer risk by smoking exposure using data collected in the late-1950s and early-1960s. Methods: This case–control study examined colorectal cancer risk by lifetime smoking history. There were 1365 patients who visited Roswell Park Cancer Institute (RPCI) between 1957 and 1965 diagnosed with primary, incident colorectal cancers that were matched to 4096 malignancy-free controls on gender and age. Odds ratios were calculated using separate logistic regression models for each smoking exposure, while controlling for other tobacco use, county of residence, race, age, gender, and body mass index (BMI). Results: The adjusted OR for individuals who reported their greatest level of smoking to be more than 1 pack/day was 0.87 (95% CI = 0.67–1.15). Among those who smoked 42 or more years, the adjusted OR was 0.89 (95% CI = 0.68–1.15) compared to those who never smoked. For individuals who smoked more than 45 pack-years, the OR was 0.92 (95% CI = 0.72–1.19). The results did not differ significantly by gender, although men had considerably greater exposure compared to women. Results also did not differ by colorectal sub-site. Conclusion: No association was found between long-term cigarette smoking and colorectal cancer risk. These results are in accord with studies that followed cohorts throughout the 1950s and 1960s. Methodological limitations, such as missing data on covariates and the higher incidence of smoking-related illness in a hospital setting, may have contributed to the null results found in this study. Prolonged population exposure to cigarettes and perhaps a changing product may explain why more recent studies have reported a positive association between smoking and colorectal cancer.     

Smoking and other risk factors for pancreatic cancer: A cohort study in men in Lithuania

Background: Cancer of the pancreas is a relatively rare, but highly fatal cancer worldwide. Cigarette smoking has been recognized as an important risk factor, but the relation to other potential determinants is still inconsistent. We investigated the association between different lifestyle, biological and anthropometric factors and the risk of pancreatic cancer in a prospective population-based cohort study from Kaunas, Lithuania. Methods: Our study included 7132 urban men initially free from any diagnosed cancer, followed for up to 30 years. 77 incident cases of pancreatic cancer were identified. Cox proportional hazards regression models were used to estimate hazard ratios (HR) and corresponding 95% confidence intervals (95% CI). Results: Compared to never smokers, current smokers had a significantly increased risk of pancreatic cancer, HR was 1.79 (95% CI 1.03–3.09) after adjustment for age, body mass index, education and alcohol consumption. Among smokers, a significant association with higher smoking intensity was shown (≥20 cigarettes/day: HR = 2.60; 95% CI 1.42–4.76, P_trend = 0.046). We also observed a significantly increased risk for ≥30 pack-years of smoking (HR = 2.24; 95% CI 1.12–4.49, P_trend = 0.16) and for age at starting smoking <18 years (HR = 2.29; 95% CI 1.11–4.70, P_trend = 0.43) as compared to never smokers. Alcohol consumption, body mass index and total cholesterol level were not significantly associated with pancreatic cancer. Conclusions: Smoking significantly increases pancreatic cancer incidence and its high prevalence in Lithuania may partly explain high incidence of the disease. No convincing evidence was found that alcohol consumption, body mass index or serum cholesterol level were associated with pancreatic cancer risk, although the assessment was limited by the lack of statistical power.     

Surveillance,Epidemiology, and End Results-based analysis of the impact of preoperative or postoperative radiotherapy on survival outcomes for T3N0 rectal cancer

Purpose: Preoperative chemoradiation has been established as standard of care for T3/T4 node-positive rectal cancer. Recent work, however, has called into question the overall benefit of radiation for tumors with lower risk characteristics, particularly T3N0 rectal cancers. We retrospectively analyzed T3N0 rectal cancer patients and examined how outcomes differed according to the sequence of treatment received. Methods: The Surveillance, Epidemiology, and End Results (SEER) database was used to analyze T3N0 rectal cancer cases diagnosed between 1998 and 2008. Treatment consisted of surgery alone (No RT), preoperative radiation followed by surgery (Neo-Adjuvant RT), or surgery followed by postoperative radiation (Adjuvant RT). Demographic and tumor characteristics of the three groups were compared using t-tests for the comparison of means. Survival information from the SEER database was utilized to estimate cause-specific survival (CSS) and to generate Kaplan–Meier survival curves. Multivariate analysis (MVA) of features associated with outcomes was conducted using Cox proportional hazards regression models with Adjuvant RT, Neo-Adjuvant RT, No RT, histological grade, tumor size, year of diagnosis, and demographic characteristics as covariates. Results: 10-Year CSS estimates were 66.1% (95% CI 62.3–69.6%; P = 0.02), 73.5% (95% CI 68.9–77.5%; P = 0.02), and 76.1% (95% CI 72.4–79.4%; P = 0.02), for No RT, Neo-Adjuvant RT, and Adjuvant RT, respectively. On MVA, Adjuvant RT (HR = 0.688; 95% CI, 0.578–0.819; P < 0.001) was associated with significantly decreased risk for cancer death. By contrast, Neo-Adjuvant RT was not significantly associated with improved cancer survival (HR = 0.863; 95% CI, 0.715–1.043; P = 0.127). Conclusion: Adjuvant RT was associated with significantly higher CSS when compared with surgery alone, while the benefit of Neo-Adjuvant RT was not significant. This indicates that surgery followed by Adjuvant RT may still be an important treatment plan for T3N0 rectal cancer with potentially significant survival advantages over other treatment sequences.     

Associations of body mass index with cancer incidence among populations,genders, and menopausal status: A systematic review and meta-analysis

In order to further reveal the differences of association between body mass index (BMI) and cancer incidence across populations, genders, and menopausal status, we performed comprehensive meta-analysis with eligible citations. The risk ratio (RR) of incidence at 10 different cancer sites (per 5 kg/m² increase in BMI) were quantified separately by employing generalized least-squares to estimate trends, and combined by meta-analyses. We observed significantly stronger association between increased BMI and breast cancer incidence in the Asia⿿Pacific group (RR 1.18:1.11⿿1.26) than in European⿿Australian (1.05:1.00⿿1.09) and North-American group (1.06:1.03⿿1.08) (meta-regression p < 0.05). No association between increased BMI and pancreatic cancer incidence (0.94:0.71⿿1.24) was shown in the Asia⿿Pacific group (meta-regression p < 0.05), whereas positive associations were found in other two groups. A significantly higher RR in men was found for colorectal cancer in comparison with women (meta-regression p < 0.05). Compared with postmenopausal women, premenopausal women displayed significantly higher RR for ovarian cancer (pre- vs. post- = 1.10 vs. 1.01, meta-regression p < 0.05), but lower RR for breast cancer (pre- vs. post- = 0.99 vs. 1.11, meta-regression p < 0.0001). Our results indicate that overweight or obesity is a strong risk factor of cancer incidence at several cancer sites. Genders, populations, and menopausal status are important factors effecting the association between obesity and cancer incidence for certain cancer types.     

Cancer mortality and occupational exposure to aromatic amines and inhalable aerosols in rubber tire manufacturing in Poland

Aim: Most data on carcinogenic risk in the rubber industry are based on data from Western countries. This study assessed cancer risks in a retrospective cohort in a Polish tire manufacturing plant, relying on quantified exposure to inhalable aerosols and aromatic amines instead of job titles or external comparisons. Methods: Cumulative exposure for all exposures was assigned to cohort members based on estimates from a company-specific JEM. Cancer risks associated with cumulative exposure adjusted for co-exposures, gender and year of birth were calculated. Results: Exposure levels were higher for women than for men. Aromatic amine exposure was significantly associated with increased urinary bladder cancer risk (RR = 7.32–8.27), depending on exposure level, and prostate cancer at low levels only (RR = 5.86). In women, increased risks were found for all cancers (RR = 2.50) and of the digestive organs and peritoneum (RR = 4.54) at low level only, while an exposure-response association with breast cancer risk was found. Inhalable aerosol exposure was associated with cancers of the liver and intrahepatic bile ducts in a dose-dependent manner, while dose-dependent reduced risks were found for respiratory cancers (most notably the larynx) and cancer of the colon. Conclusions: Increased risks for specific cancer sites in this rubber plant were similar to Western Europe and the US. However, several cancer risks were gender-specific which could relate to higher exposure levels in women or to differences in exposures to chemicals not assessed in this study.     

Prolonged breastfeeding reduces risk of breast cancer in Sri Lankan women: A case–control study

Goal: To assess the association between duration of breastfeeding and the risk of breast cancer in Sri Lankan women. Methods: We conducted a case–control study in women aged 30–64 years in selected health care facilities in the Western province. A total of 100 recent cases of breast cancer (histologically confirmed) and 203 controls (age and parity matched) were included. Detailed information regarding breastfeeding, menstruation, reproductive factors, passive smoking and other confounders was collected using a structured questionnaire. Adjusted odds ratios and 95% confidence intervals were calculated using multiple logistic regressions. Principle results: Multivariate analysis found that those women who breastfed for ≥24 months during lifetime had significantly lower risk of breast cancer than those who breastfed for less than 24 months (OR = 0.40; 95%CI = 0.22, 0.73). Compared to 0–11 months of lifetime breastfeeding, there was a 66.3% reduction in breast cancer risk in women who breastfed for 12–23 months, 87.4% reduction in 24–35 months and 94% reduction in 36–47 months categories. The mean duration of breastfeeding per child for ≥12 months was also associated with reduced risk of breast cancer (OR = 0.52; 95%CI = 0.28, 0.94). The significant factors associated with increased risk of breast cancer were: post-menopausal women (OR = 1.74; 95%CI = 1.01, 3.01); having an abortion in the past (OR = 3.42; 95%CI = 1.75, 6.66) and exposure to passive smoking (OR = 2.96, 95%CI = 1.53, 5.75). Major conclusions: Prolonged breastfeeding significantly reduces the risk of breast cancer and this protective effect was supported by a dose–response relationship. Risk due to passive smoking should be emphasized in anti-smoking programmes.     

Prepubertal octylphenol exposure up-regulate BRCA1 expression,down-regulate ERα expression and reduce rat mammary tumorigenesis

Background: Endogenous estrogens play an important role in the development of breast cancer. Octylphenol (OP) and genistein (GEN) are estrogen-like chemicals. Prepubertal estradiol and genistein exposure can up-regulate BRCA1 mRNA in mammary gland and reduce futuer breast cancer risk. In the present study, the effects of prepubertal exposure to high-dose OP and GEN on mammary carcinogenesis and the association with the expression of BRCA1 and ERα were investigated. Methods: Prepubertal female Sprague–Dawley rats were exposed to 20, 40, 80 mg/kg OP daily from postnatal day (PND) 22–28, subsequently, the rats were given a single dose of 100 mg/kg 7,12-dimethylbenz [a] anthracene (DMBA) on PND42 to induce mammary tumor. Results: The incidence of DMBA-induced mammary tumors significantly decreased when rats were treated with 40 mg/kg OP. BRCA1 mRNA and protein expression were found up-regulated and ERα expression was down-regulated in the mammary tumor when rats were exposed to 40 mg/kg octylphenol. Conclusion: Exposure 40 mg/kg octylphenol can reduce later breast cancer risk in prepubertal Sprague–Dawley rats, the protective effect of OP is associated with persistent up-regulation of BRCA1 and down-regulation of ERα in the mammary tumor.     

Impairment of the non-homologous end joining and homologous recombination pathways of DNA double strand break repair: Impact on spontaneous and radiation-induced mammary and intestinal tumour risk in Apcmin/+ mice

Female Apc^min/+ mice carrying the BALB/c variant of Prkdc or heterozygous knockout for Xrcc2, were sham- or 2 Gy X-irradiated as adults to compare the effect of mild impairments of double–strand break (DSB) repair pathways, non-homologous end joining (NHEJ) and homologous recombination (HR) respectively on spontaneous and radiation–induced mammary and intestinal tumorigenesis. Mice with impaired NHEJ showed no difference in incidence of spontaneous mammary tumours, compared with matched controls, (2.46 fold, P = 0.121) and significantly less following irradiation (radiation–induced excess; 0.35 fold, P = 0.008). In contrast mice with impaired HR presented with significantly less spontaneous mammary tumours than matched controls (0.33 fold, P = 0.027) and significantly more following irradiation (radiation-induced excess; 3.3 fold, P = 0.016). Spontaneous and radiation-induced intestinal adenoma multiplicity in the same groups were significantly greater than matched controls for mice with impaired NHEJ (sham; 1.29 fold, P < 0.001, radiation–induced excess; 2.55 fold, P < 0.001) and mice with impaired HR showed no significant differences (sham; 0.92 fold, P = 0.166, radiation-induced excess; 1.16, P = 0.274). Genetic insertion events were common in spontaneous tumours from NHEJ impaired mice compared with matched controls. γH2AX foci analysis suggests a significantly faster rate of DSB repair (MANOVA P < 0.001) in intestinal than mammary tissue; apoptosis was also higher in irradiated intestine.To conclude, results suggest that pathway of choice for repair of spontaneous and radiation-induced DSBs is influenced by tissue type. NHEJ appears to play a greater role in DSB repair in intestinal tissue since impairment by functional change of Prkdc significantly increases the rate of mis-repair in intestinal but not mammary tissue. HR appears to play a greater role in DSB repair in adult mammary tissue since impaired HR results in significant changes in mammary but not in the intestinal tumorigenesis. This indicates that early DNA damage response and repair is important for cancer susceptibility and plays a role in determining tissue specificity of cancer risk.     

STK15 rs2273535 polymorphism and cancer risk: A meta-analysis of 74,896 subjects

Background: It has been suggested that the serine/threonine kinase 15 (STK15) T91A rs2273535 polymorphism is associated with susceptibility to cancer. However, the results are conflicting. We performed this meta-analysis to derive a more precise estimation of the relationship. Methods: PubMed was searched to select studies. Case–control studies containing available genotype frequencies of the STK15 rs2273535 polymorphism were chosen, and the odds ratio (OR) with its 95% confidence interval (CI) was utilized to assess the strength of association. Results: 52 studies – including 34,057 cases and 40,839 controls – were identified. A significant effect of the STK15 rs2273535 polymorphism on cancer risk was found (AA vs. TT: OR = 1.13, 95%CI = 1.01–1.26, P_{heterogeneity} < 0.001; AA vs. TA/TT: OR = 1.12, 95%CI = 1.02–1.22, P_{heterogeneity} < 0.001; TA/AA vs. TT: OR = 1.06, 95%CI = 1.01–1.12, P_{heterogeneity} < 0.001). Stratified analysis by cancer type revealed that the STK rs2273535 polymorphism may contribute to the risk of breast cancer (AA vs. TT: OR = 1.21, 95%CI = 1.01–1.44, P_{heterogeneity} = 0.002), colorectal cancer (AA vs. TA/TT: OR = 1.24, 95%CI = 1.05–1.47, P_{heterogeneity} = 0.124), and esophageal cancer (AA vs. TA/TT: OR = 1.19, 95%CI = 1.02–1.39, P_{heterogeneity} = 0.148). Further subgroup analysis by ethnicity indicated that there was a statistically increased cancer risk in Asians (AA vs. TA/TT: OR = 1.20, 95%CI = 1.05–1.37, P_{heterogeneity} = 0.004). Conclusion: This meta-analysis suggests that the STK15 rs2273535 polymorphism is a candidate gene polymorphism for cancer susceptibility, especially in Asian populations.     

No association between educational level and pancreatic cancer incidence in the European Prospective Investigation into Cancer and Nutrition

Introduction: Until now, studies examining the relationship between socioeconomic status and pancreatic cancer incidence have been inconclusive. Aim: To prospectively investigate to what extent pancreatic cancer incidence varies according to educational level within the European Prospective Investigation into Cancer and Nutrition (EPIC) study. Methods: In the EPIC study, socioeconomic status at baseline was measured using the highest level of education attained. Hazard ratios by educational level and a summary index, the relative indices of inequality (RII), were estimated using Cox regression models stratified by age, gender, and center and adjusted for known risk factors. In addition, we conducted separate analyses by age, gender and geographical region. Results: Within the source population of 407, 944 individuals at baseline, 490 first incident primary pancreatic adenocarcinoma cases were identified in 9 European countries. The crude difference in risk of pancreatic cancer according to level of education was small and not statistically significant (RII = 1.14, 95% CI 0.80–1.62). Adjustment for known risk factors reduced the inequality estimates to only a small extent. In addition, no statistically significant associations were observed for age groups (adjusted RII_{≤ 60 years} = 0.85, 95% CI 0.44–1.64, adjusted RII_{>60 years} = 1.18, 95% CI 0.73–1.90), gender (adjusted RII_male = 1.20, 95% CI 0.68–2.10, adjusted RII_female = 0.96, 95% CI 0.56–1.62) or geographical region (adjusted RII_{Northern Europe} = 1.14, 95% CI 0.81–1.61, adjusted RII_{Middle Europe} = 1.72, 95% CI 0.93–3.19, adjusted RII_{Southern Europe} = 0.75, 95% CI 0.32–1.80). Conclusion: Despite large educational inequalities in many risk factors within the EPIC study, we found no evidence for an association between educational level and the risk of developing pancreatic cancer in this European cohort.     

Cancer survival in patients with HIV/AIDS in the era of highly active antiretroviral therapy in Taiwan: A population-based cohort study

Objectives: HIV-related immunosuppression has been associated with the development of AIDS-defining malignancies. We examined the overall survival of HIV-infected patients who developed cancer. Design: A retrospective cohort study. Methods: Using the Taiwan Longitudinal Health Insurance Database, we compared patients diagnosed with HIV (n = 9918) between January 1, 2002, and December 31, 2007 with age-matched controls (n = 99,180). Each patient was followed until the end of 2009 (least 2 years after the initial HIV diagnosis) to evaluate the incidence of malignancies. Results: The risk of overall malignancies in the HIV-infected cohort was 1.88 times higher than the risk of a first malignancy in the age-matched non-HIV infected cohort (incidence rate ratio [IRR]) = 2.05, p < 0.0001). The diagnosis of a malignancy was negatively correlated with survival in the HIV-infected cohort (p < 0.0011), and HIV infection had a synergistic effect on the survival of patients with malignancies compared with the non-HIV infected cohort, all of who had been newly diagnosed with cancer (p < 0.0001). However, the difference in the risk of developing nasopharyngeal carcinoma (NPC), a highly prevalent malignancy in Taiwan, between the two cohorts was not significant (IRR = 0.22, 95% CI = 0.03–1.65). Conclusions: The risk of cancer in HIV-infected patients in Taiwan has increased significantly in the era of highly active antiretroviral therapy. A history of HIV significantly affected the survival of the patients in our study cohort after they developed cancer.Evidence level: 2B.     

Malignant pleural mesothelioma incidence and survival in the Republic of Ireland 1994–2009

ObjectiveMalignant pleural mesothelioma (MPM) is a rare malignancy associated with exposure to asbestos. The protracted latent period of MPM means that its incidence has continued to rise across Europe after the introduction of restrictions on asbestos use. In order to obtain a clearer indication of trends in the Republic of Ireland (ROI), incidence and survival were assessed based on all MPM cases reported since the establishment of the National Cancer Registry of Ireland (NCR).MethodsNCR recorded 337 MPM diagnoses in the ROI during 1994–2009. Survival was assessed for all cases diagnosed with adequate follow-up (n = 330). Crude and European age-standardized incidence rates were calculated for all cases and for 4-year periods. A Cox model of observed (all-cause) survival was used to generate hazard ratios for the effect of: gender; age at diagnosis; diagnosis cohort; region of residence; histological type; and tumour stage. Single P-values for the variables indicated were calculated using either a stratified log-rank test or stratified trend test.ResultsOver the study period the age-standardized MPM incidence in the ROI rose from 4.98 cases per million (cpm) to 7.24 cpm. The 1-year survival rate for all MPM cases was 29.6% (CI 24.7–34.6%). Excess mortality risk was associated with age at diagnosis (75–89 yrs vs. 55–64 yrs, HR 1.88, 95% CI 1.35–2.63, P < 0.001) and tumour stage (III vs. I HR 1.57, 95% CI 1.00–2.48, P < 0.05; IV vs. I HR 1.55, 95% CI 1.08–2.21, P < 0.05). Age showed a significant survival trend (P < 0.001) but tumour stage did not (P = 0.150). There was significant heterogeneity between the survival of patients resident in different regions (P = 0.027).ConclusionMPM incidence and mortality continued to rise in the ROI after the restrictions on asbestos use and the predictors of survival detected in this study are broadly consistent with those identified for other countries.     

Évaluation de l’exposition des travailleurs du service de radioimmunoanalyse du Bénin aux rayonnements ionisants de l’iode 125

Occupational radiation dose of staff handling ¹²⁵I assessment at the Benin radioimmunoassay laboratory, have been undertaken from October 2012 to April 2013 to determine level of radiation safety. Equivalent dose to skin, whole body and extremities, were measured by the mean of thermoluminescence dosimetry. Firstly, three permanent workers and two students were provided with finger ring dosimeters to wear at index finger base of both hands. Ring dosimeters were used for four months. Secondly, three permanent workers and three students were provided with badge dosimeters to wear at the chest level. Badge dosimeters were renewed monthly for six months. The exposed ring and badge dosimeters were evaluated in Ghana. Permanent workers highest average equivalent dose received at index finger base of both hands was 142.75 ± 89.54, microSV/2 months and that of students was 34.69 ± 29.23, microSV/2 months. Workers skin exposure was below one third of prescribed dose limits for permanents workers (500mSv/yr) and students (150mSv/yr). Whole body exposure, expressed in mSv/month, of permanent workers and students, respectively ranged from 0.12 to 0.23 and from 0.11 to 0.16. Radio-immuno-assay laboratory workers are weakly exposed to ionizing radiation. They are safe from deterministic effect risk.