REVIEW EDITORIAL For reprint orders, please contact: [email protected]
Prostate cancer: an occupational hazard? “...occupation in and of itself is not a hazard, but the few studies of aggressive/lethal prostate cancers have found a number of possible occupational associations.” L Joseph Su*,1 & Elizabeth TH Fontham2 Prostate cancer (PCa) remains the most frequently diagnosed invasive cancer and the second leading cause of cancer death in American men; however, few modifiable risk factors have been identified to aid in prevention efforts [1] . Potential risk factors proposed for PCa in general that are most plausible include diet, hormones, physical activity, marital status, family history of PCa, race, smoking, anthropometry and occupational history [2–9] . However, epidemiological studies thus far have yielded mixed results. These inconsistent findings may be attributed to failure to examine associations within the context of PCa aggressiveness. Although all men are at risk of developing PCa, the majority of PCas are indolent and will never progress to malignancy that causes death or disability. It is the extent of the disease aggressiveness that is most clinically important. Searching for modifiable factors specific for aggressive/lethal PCa is essential for designing and implementing preventive strategies to reduce the burden to the society and to avoid the death of this disease.
A wide variety of occupations and occupational environmental exposures have been associated with PCa in predominately retrospective studies. Several occupational risk factors including exposures to diesel exhaust, pesticides, agricultural chemicals and whole-body vibration (WBV) have been hypothesized to be associated with PCa in previous assessments, although few, if any, have been clearly confirmed in subsequent studies. Reviews on this topic are scarce. Most attention has been paid to farming, metal working and the rubber industry, with exposures to herbicides and pesticides, cadmium, polycyclic aromatic hydrocarbons and engine emissions proposed as linked to the underlying mechanisms [3,10–12] . There is no overall consistency among the results of relevant studies regarding associations examined between occupational history and PCa risk. Furthermore, there has been little consideration of risk factors focusing on highly aggressive PCa, rather than general PCa risk. A recent study by our group presented at the 12th Annual AACR International
KEYWORDS
• aggressiveness • diet • lifestyle • occupation • prostate cancer • sitting • whole-body vibration
“Although all men are at risk of developing prostate cancer, the majority of prostate cancers are indolent and will never progress to malignancy that causes death or disability.”
Division of Cancer Control & Population Sciences, National Cancer Institute, 9609 Medical Center Drive, Room 4E212, Rockville, MD 20850, USA 2 Louisiana State University Health Sciences Center, School of Public Health, 2020 Gravier Street, 3rd Floor, New Orleans, LA 70112, USA *Author for correspondence: Tel.: +1 240 276 6822; [email protected] 1
10.2217/FON.14.33 © 2014 Future Medicine Ltd
Future Oncol. (2014) 10(6), 903–906
part of
ISSN 1479-6694
903
Editorial Su & Fontham
“We have found no study
published to date linking financial professionals and prostate cancer.”
904
Conference on Frontiers in Cancer Prevention Research in National Harbor (MD, USA) examined the relationship between PCa aggressiveness and occupational history in a population-based study [13] . This study found that men who worked as a landscaper or grounds keeper, or worked at a florist/garden shop, greenhouse or plant nursery for 6 months or more had a higher chance of having highly aggressive PCa at diagnosis (odd ratios [ORs]: 1.61 [95% CI: 1.16–2.23] and 2.18 [95% CI: 1.35–3.54], respectively). This study also reported a significantly higher odds of aggressive PCa at diagnosis among men reporting their longest held job was as a truck driver (OR: 2.87; 95% CI: 1.14–7.23), a construction laborer (OR: 2.66; 95% CI: 1.09–6.49) or a financial professional (OR: 3.55; 95% CI: 1.64–9.27) when compared with men who reported educator as their longest job. After presentation of the findings, significant media attention was focused on the finding related to trucker drivers with the question being whether PCa represents an occupational hazard among truckers. Clearly additional studies are needed to answer that question and to better understand the nature of the relationships between PCa and these occupations. The relationship between farming and PCa has been commonly studied. It is suggested that farmers are at increased risk for PCa owing to exposure to agricultural chemicals, such as pesticides, acetic acid and diesel and gasoline engine emissions. One study analyzed the relationships between PCa and ten agricultural pesticides rather than farming as a job without regard to exposures. It was found that exposure to pesticides was associated with a highly statistically significant excess risk of PCa [14] . A meta-analysis combining 12 case–control studies with a total of 3989 cases and 7393 controls concluded that farming is a risk factor for PCa, but this increased risk may not be owing to exposure to pesticides alone [3] . However, none of the studies included in the meta-analysis stratified PCa by tumor aggressiveness at diagnosis – that is, aggressive versus indolent. There is a need to clearly identify the factors in farming that increase the risk of PCa in order to implement appropriate prevention strategies to reduce the risk of PCa for men working in farming or related agricultural environments who may have substantial exposure to commonly applied chemicals. Moreover, a focus on the aggressive type of PCa is needed to avoid potential m isclassification of findings regarding the level of risk.
Future Oncol. (2014) 10(6)
Even less is known about the risk of aggressive PCa associated with other occupations. Some studies examining WBV experienced by heavy equipment operators, construction workers and transportation laborers have reported a nonsignificant elevated risk for PCa. One study found a weak association between WBV exposure and PCa, concluding that the finding is only suggestive because of the inability to isolate WBV from other known correlated risk factors, such as polycyclic aromatic hydrocarbons exposure, obesity and a lack of exercise [15] . Studies have linked WBV with increased circulating testosterone level and with elevated risk of prostatitis, both known risk factors for PCa. However, a systematic review and meta-analysis of PCa and driving occupations with WBV found a nonsignificant weak association [15] . When the analysis was further stratified into truck drivers, bus drivers, heavy machinery operators and railroad transport workers, only bus drivers were found to have elevated risk for PCa. Advances in automobile design and engineering in recent decades have produced smoother riding vehicles, which have drastically reduced the amount of mechanical vibration experienced by drivers. It is anticipated that the effect of WBV should be more evident among heavy equipment operators than truck or bus drivers. In addition, WBV experienced is likely to be quite different among drivers of different types of trucks. A further assessment needs to quantify the unit time WBV in each type of vehicle. Indeed, we did not observe association between aggressive PCa and heavy machinery operator, such as cranes, backhoe operators or bulk terminal operators, but tractor trailer drivers in our study [13] . Therefore, although WBV is a plausible risk factor, it may or may not have a causal association with aggressive PCa. Long periods of sitting have been proposed to be a PCa risk factor. In fact, one study as early as 1994 proposed that long-term sitting may contribute to the occupational risk of PCa [16] . That said, many of the long-hauling tractor trailer drivers who are on the road away from home for extended periods of time may have compromised diets and limited leisure physical activities, which may also contribute to risk of aggressive PCa. A prospective study of concrete workers in Denmark found significantly elevated PCa when compared with the general population [17] . Unlike tractor trailer drivers, construction laborers have significant higher energy expenditure
future science group
Prostate cancer: an occupational hazard? resulting from occupation-related physical activities. Nevertheless, a study of the Swedish Construction Workers cohort suggested that an elevated BMI was a significant contributor to aggressive PCa among men with this occupation [18] . Another study found significantly elevated risk of PCa among constructional workers [19] ; however, cigarette smoking was proposed to be the main contributing factor for cancer among these construction workers. We also found a significantly higher proportion of construction laborers reported being current (30%) or past (53%) smokers in our study [13] . Cigarette smoking has been associated with increased risk of biochemical disease recurrence, metastasis and mortality after radical prostatectomy [20] . It is highly plausible that the observed risk of aggressive PCa can be attributable to the high prevalence of cigarette smoking among construction laborers. We have found no study published to date linking financial professionals and PCa. Studies have generally grouped financial professionals with other white collar professional together when examining disease risk [16] . No factor has been identified to associate aggressive PCa with this occupation. Conceptually, financial professionals may experience extended sitting period. At the same time, although only approximately 10% of the men in our study held this occupation reported as current smoker at the time of PCa diagnosis, more than 54% of financial professionals reported as past smokers. Both long seating period and cigarette smoking have been associated with aggressive PCa as elucidated earlier. A closer look at this occupation may offer a better explanation of the contributing factors on this disease. References 1
2
3
Siegel R, Naishadham D, Jemal A. Cancer statistics, 2013. CA Cancer J. Clin. 63, 11–30 (2013). Allott EH, Masko EM, Freedland SJ. Obesity and prostate cancer: weighing the evidence. Eur. Urol. 63, 800–809 (2013). Ragin C, Davis-Reyes B, Tadesse H et al. Farming, reported pesticide use, and prostate cancer. Am. J. Men Health 7, 102–109 (2013).
4
Colloca G, Venturino A. The evolving role of familial history for prostate cancer. Acta Oncol. 50, 14–24 (2011).
5
Zu K, Giovannucci E. Smoking and aggressive prostate cancer: a review of the
future science group
In summary, well-established modifiable risk factors for PCa are limited. PCa is the most common cancer in men, and the vast majority of studies have been directed at overall PCa risk despite the fact that it is a heterogeneous disease. Indolent PCas and aggressive/lethal PCas may well have different etiologic factors and failure to take that heterogeneity into account can lead to misclassification and inconsistency in findings across studies. Studies of risk factors should be focused on the aggressive/lethal form of the disease. To date, the limited literature on occupational factors suggests that occupation in and of itself is not a hazard, but the few studies of aggressive/lethal prostate cancers have found a number of possible occupational associations. Whether specific occupations will be reported consistently when additional studies of the aggressive phenotype of the disease are conducted remains to be determined. Furthermore, confounding by lifestyle, such as physical activity and dietary factors, is a plausible explanation for occupational associations to date. Additional studies of occupation and associated behavioral factors in men with aggressive PCa would be a notable contribution to development of prevention strategies. Financial & competing interest disclosure The authors have no relevant affiliations or financial involvement with any organization or entity with a financial interest in or financial conflict with the subject matter or materials discussed in the manuscript. This includes employment, consultancies, honoraria, stock ownership or options, expert testimony, grants or patents received or pending or royalties. No writing assistance was utilized in the production of this manuscript. epidemiologic evidence. Cancer Causes Control. 20, 1799–1810 (2009).
6
7
8
9
Editorial
Imamoto T, Suzuki H, Yano M et al. The role of testosterone in the pathogenesis of prostate cancer. Int. J. Urol. Off. J. Jap. Urol. Assoc. 15, 472–480 (2008). Pan SY, DesMeules M. Energy intake, physical activity, energy balance, and cancer: epidemiologic evidence. Methods Mol. Biol. 472, 191–215 (2009). Mordukhovich I, Reiter PL, Backes DM et al. A review of African American–white differences in risk factors for cancer: prostate cancer. Cancer Causes Control. 22, 341–357 (2011). Robinson WR, Poole C, Godley PA. Systematic review of prostate cancer’s
association with body size in childhood and young adulthood. Cancer Causes Control. 19, 793–803 (2008). 10 Kogevinas M, Sala M, Boffetta P, Kazerouni
N, Kromhout H, Hoar-Zahm S. Cancer risk in the rubber industry: a review of the recent epidemiological evidence. Occup. Environ. Med. 55, 1–12 (1998). 11 van der Gulden JW. Metal workers and
repairmen at risk for prostate cancer: a review. Prostate 30, 107–116 (1997). 12 Parent ME, Siemiatycki J. Occupation and
prostate cancer. Epidemiol. Rev. 23, 138–143 (2001). 13 Su LJ, Sun W, Fontham ETH, Bensen
JT, Mohler JL. Occupational risk factors for high aggressive prostate cancer in a
www.futuremedicine.com
905
Editorial Su & Fontham population-based study of African Americans and European Americans. Presented at: The 12th Annual AACR International Conference On Frontiers In Cancer Prevention Research. National Harbor, MD, USA, 28–31 October 2013. 14 Parent ME, Desy M, Siemiatycki J. Does
exposure to agricultural chemicals increase the risk of prostate cancer among farmers? McGill J. Med. 12, 70–77 (2009). 15 Young E, Kreiger N, Purdham J,
Sass-Kortsak A. Prostate cancer and driving occupations: could whole body vibration play
906
a role? Int. Arch. Occ. Env. Health 82, 551–556 (2009). 16 Hsing AW, McLaughlin JK, Zheng W, Gao
YT, Blot WJ. Occupation, physical activity, and risk of prostate cancer in Shanghai, People’s Republic of China. Cancer Causes Control. 5, 136–140 (1994). 17 Knutsson A, Damber L, Jarvholm B. Cancers in
concrete workers: results of a cohort study of 33,668 workers. Occup. Environ. Med. 57, 264–267 (2000). 18 Stocks T, Hergens MP, Englund A, Ye
W, Stattin P. Blood pressure, body size and
Future Oncol. (2014) 10(6)
prostate cancer risk in the Swedish Construction Workers cohort. Int. J. Cancer 127, 1660–1668 (2010). 19 Keller JE, Howe HL. Cancer in Illinois
construction workers: a study. Am. J. Ind. Med. 24, 223–230 (1993). 20 Moreira DM, Aronson WJ, Terris MK et al.
Cigarette smoking is associated with an increased risk of biochemical disease recurrence, metastasis, castration-resistant prostate cancer, and mortality after radical prostatectomy: results from the SEARCH database. Cancer 120, 197–204 (2014).
future science group
Prostate cancer: an occupational hazard? “...occupation in and of itself is not a hazard, but the few studies of aggressive/lethal prostate cancers have found a number of possible occupational associations.” L Joseph Su*,1 & Elizabeth TH Fontham2 Prostate cancer (PCa) remains the most frequently diagnosed invasive cancer and the second leading cause of cancer death in American men; however, few modifiable risk factors have been identified to aid in prevention efforts [1] . Potential risk factors proposed for PCa in general that are most plausible include diet, hormones, physical activity, marital status, family history of PCa, race, smoking, anthropometry and occupational history [2–9] . However, epidemiological studies thus far have yielded mixed results. These inconsistent findings may be attributed to failure to examine associations within the context of PCa aggressiveness. Although all men are at risk of developing PCa, the majority of PCas are indolent and will never progress to malignancy that causes death or disability. It is the extent of the disease aggressiveness that is most clinically important. Searching for modifiable factors specific for aggressive/lethal PCa is essential for designing and implementing preventive strategies to reduce the burden to the society and to avoid the death of this disease.
A wide variety of occupations and occupational environmental exposures have been associated with PCa in predominately retrospective studies. Several occupational risk factors including exposures to diesel exhaust, pesticides, agricultural chemicals and whole-body vibration (WBV) have been hypothesized to be associated with PCa in previous assessments, although few, if any, have been clearly confirmed in subsequent studies. Reviews on this topic are scarce. Most attention has been paid to farming, metal working and the rubber industry, with exposures to herbicides and pesticides, cadmium, polycyclic aromatic hydrocarbons and engine emissions proposed as linked to the underlying mechanisms [3,10–12] . There is no overall consistency among the results of relevant studies regarding associations examined between occupational history and PCa risk. Furthermore, there has been little consideration of risk factors focusing on highly aggressive PCa, rather than general PCa risk. A recent study by our group presented at the 12th Annual AACR International
KEYWORDS
• aggressiveness • diet • lifestyle • occupation • prostate cancer • sitting • whole-body vibration
“Although all men are at risk of developing prostate cancer, the majority of prostate cancers are indolent and will never progress to malignancy that causes death or disability.”
Division of Cancer Control & Population Sciences, National Cancer Institute, 9609 Medical Center Drive, Room 4E212, Rockville, MD 20850, USA 2 Louisiana State University Health Sciences Center, School of Public Health, 2020 Gravier Street, 3rd Floor, New Orleans, LA 70112, USA *Author for correspondence: Tel.: +1 240 276 6822; [email protected] 1
10.2217/FON.14.33 © 2014 Future Medicine Ltd
Future Oncol. (2014) 10(6), 903–906
part of
ISSN 1479-6694
903
Editorial Su & Fontham
“We have found no study
published to date linking financial professionals and prostate cancer.”
904
Conference on Frontiers in Cancer Prevention Research in National Harbor (MD, USA) examined the relationship between PCa aggressiveness and occupational history in a population-based study [13] . This study found that men who worked as a landscaper or grounds keeper, or worked at a florist/garden shop, greenhouse or plant nursery for 6 months or more had a higher chance of having highly aggressive PCa at diagnosis (odd ratios [ORs]: 1.61 [95% CI: 1.16–2.23] and 2.18 [95% CI: 1.35–3.54], respectively). This study also reported a significantly higher odds of aggressive PCa at diagnosis among men reporting their longest held job was as a truck driver (OR: 2.87; 95% CI: 1.14–7.23), a construction laborer (OR: 2.66; 95% CI: 1.09–6.49) or a financial professional (OR: 3.55; 95% CI: 1.64–9.27) when compared with men who reported educator as their longest job. After presentation of the findings, significant media attention was focused on the finding related to trucker drivers with the question being whether PCa represents an occupational hazard among truckers. Clearly additional studies are needed to answer that question and to better understand the nature of the relationships between PCa and these occupations. The relationship between farming and PCa has been commonly studied. It is suggested that farmers are at increased risk for PCa owing to exposure to agricultural chemicals, such as pesticides, acetic acid and diesel and gasoline engine emissions. One study analyzed the relationships between PCa and ten agricultural pesticides rather than farming as a job without regard to exposures. It was found that exposure to pesticides was associated with a highly statistically significant excess risk of PCa [14] . A meta-analysis combining 12 case–control studies with a total of 3989 cases and 7393 controls concluded that farming is a risk factor for PCa, but this increased risk may not be owing to exposure to pesticides alone [3] . However, none of the studies included in the meta-analysis stratified PCa by tumor aggressiveness at diagnosis – that is, aggressive versus indolent. There is a need to clearly identify the factors in farming that increase the risk of PCa in order to implement appropriate prevention strategies to reduce the risk of PCa for men working in farming or related agricultural environments who may have substantial exposure to commonly applied chemicals. Moreover, a focus on the aggressive type of PCa is needed to avoid potential m isclassification of findings regarding the level of risk.
Future Oncol. (2014) 10(6)
Even less is known about the risk of aggressive PCa associated with other occupations. Some studies examining WBV experienced by heavy equipment operators, construction workers and transportation laborers have reported a nonsignificant elevated risk for PCa. One study found a weak association between WBV exposure and PCa, concluding that the finding is only suggestive because of the inability to isolate WBV from other known correlated risk factors, such as polycyclic aromatic hydrocarbons exposure, obesity and a lack of exercise [15] . Studies have linked WBV with increased circulating testosterone level and with elevated risk of prostatitis, both known risk factors for PCa. However, a systematic review and meta-analysis of PCa and driving occupations with WBV found a nonsignificant weak association [15] . When the analysis was further stratified into truck drivers, bus drivers, heavy machinery operators and railroad transport workers, only bus drivers were found to have elevated risk for PCa. Advances in automobile design and engineering in recent decades have produced smoother riding vehicles, which have drastically reduced the amount of mechanical vibration experienced by drivers. It is anticipated that the effect of WBV should be more evident among heavy equipment operators than truck or bus drivers. In addition, WBV experienced is likely to be quite different among drivers of different types of trucks. A further assessment needs to quantify the unit time WBV in each type of vehicle. Indeed, we did not observe association between aggressive PCa and heavy machinery operator, such as cranes, backhoe operators or bulk terminal operators, but tractor trailer drivers in our study [13] . Therefore, although WBV is a plausible risk factor, it may or may not have a causal association with aggressive PCa. Long periods of sitting have been proposed to be a PCa risk factor. In fact, one study as early as 1994 proposed that long-term sitting may contribute to the occupational risk of PCa [16] . That said, many of the long-hauling tractor trailer drivers who are on the road away from home for extended periods of time may have compromised diets and limited leisure physical activities, which may also contribute to risk of aggressive PCa. A prospective study of concrete workers in Denmark found significantly elevated PCa when compared with the general population [17] . Unlike tractor trailer drivers, construction laborers have significant higher energy expenditure
future science group
Prostate cancer: an occupational hazard? resulting from occupation-related physical activities. Nevertheless, a study of the Swedish Construction Workers cohort suggested that an elevated BMI was a significant contributor to aggressive PCa among men with this occupation [18] . Another study found significantly elevated risk of PCa among constructional workers [19] ; however, cigarette smoking was proposed to be the main contributing factor for cancer among these construction workers. We also found a significantly higher proportion of construction laborers reported being current (30%) or past (53%) smokers in our study [13] . Cigarette smoking has been associated with increased risk of biochemical disease recurrence, metastasis and mortality after radical prostatectomy [20] . It is highly plausible that the observed risk of aggressive PCa can be attributable to the high prevalence of cigarette smoking among construction laborers. We have found no study published to date linking financial professionals and PCa. Studies have generally grouped financial professionals with other white collar professional together when examining disease risk [16] . No factor has been identified to associate aggressive PCa with this occupation. Conceptually, financial professionals may experience extended sitting period. At the same time, although only approximately 10% of the men in our study held this occupation reported as current smoker at the time of PCa diagnosis, more than 54% of financial professionals reported as past smokers. Both long seating period and cigarette smoking have been associated with aggressive PCa as elucidated earlier. A closer look at this occupation may offer a better explanation of the contributing factors on this disease. References 1
2
3
Siegel R, Naishadham D, Jemal A. Cancer statistics, 2013. CA Cancer J. Clin. 63, 11–30 (2013). Allott EH, Masko EM, Freedland SJ. Obesity and prostate cancer: weighing the evidence. Eur. Urol. 63, 800–809 (2013). Ragin C, Davis-Reyes B, Tadesse H et al. Farming, reported pesticide use, and prostate cancer. Am. J. Men Health 7, 102–109 (2013).
4
Colloca G, Venturino A. The evolving role of familial history for prostate cancer. Acta Oncol. 50, 14–24 (2011).
5
Zu K, Giovannucci E. Smoking and aggressive prostate cancer: a review of the
future science group
In summary, well-established modifiable risk factors for PCa are limited. PCa is the most common cancer in men, and the vast majority of studies have been directed at overall PCa risk despite the fact that it is a heterogeneous disease. Indolent PCas and aggressive/lethal PCas may well have different etiologic factors and failure to take that heterogeneity into account can lead to misclassification and inconsistency in findings across studies. Studies of risk factors should be focused on the aggressive/lethal form of the disease. To date, the limited literature on occupational factors suggests that occupation in and of itself is not a hazard, but the few studies of aggressive/lethal prostate cancers have found a number of possible occupational associations. Whether specific occupations will be reported consistently when additional studies of the aggressive phenotype of the disease are conducted remains to be determined. Furthermore, confounding by lifestyle, such as physical activity and dietary factors, is a plausible explanation for occupational associations to date. Additional studies of occupation and associated behavioral factors in men with aggressive PCa would be a notable contribution to development of prevention strategies. Financial & competing interest disclosure The authors have no relevant affiliations or financial involvement with any organization or entity with a financial interest in or financial conflict with the subject matter or materials discussed in the manuscript. This includes employment, consultancies, honoraria, stock ownership or options, expert testimony, grants or patents received or pending or royalties. No writing assistance was utilized in the production of this manuscript. epidemiologic evidence. Cancer Causes Control. 20, 1799–1810 (2009).
6
7
8
9
Editorial
Imamoto T, Suzuki H, Yano M et al. The role of testosterone in the pathogenesis of prostate cancer. Int. J. Urol. Off. J. Jap. Urol. Assoc. 15, 472–480 (2008). Pan SY, DesMeules M. Energy intake, physical activity, energy balance, and cancer: epidemiologic evidence. Methods Mol. Biol. 472, 191–215 (2009). Mordukhovich I, Reiter PL, Backes DM et al. A review of African American–white differences in risk factors for cancer: prostate cancer. Cancer Causes Control. 22, 341–357 (2011). Robinson WR, Poole C, Godley PA. Systematic review of prostate cancer’s
association with body size in childhood and young adulthood. Cancer Causes Control. 19, 793–803 (2008). 10 Kogevinas M, Sala M, Boffetta P, Kazerouni
N, Kromhout H, Hoar-Zahm S. Cancer risk in the rubber industry: a review of the recent epidemiological evidence. Occup. Environ. Med. 55, 1–12 (1998). 11 van der Gulden JW. Metal workers and
repairmen at risk for prostate cancer: a review. Prostate 30, 107–116 (1997). 12 Parent ME, Siemiatycki J. Occupation and
prostate cancer. Epidemiol. Rev. 23, 138–143 (2001). 13 Su LJ, Sun W, Fontham ETH, Bensen
JT, Mohler JL. Occupational risk factors for high aggressive prostate cancer in a
www.futuremedicine.com
905
Editorial Su & Fontham population-based study of African Americans and European Americans. Presented at: The 12th Annual AACR International Conference On Frontiers In Cancer Prevention Research. National Harbor, MD, USA, 28–31 October 2013. 14 Parent ME, Desy M, Siemiatycki J. Does
exposure to agricultural chemicals increase the risk of prostate cancer among farmers? McGill J. Med. 12, 70–77 (2009). 15 Young E, Kreiger N, Purdham J,
Sass-Kortsak A. Prostate cancer and driving occupations: could whole body vibration play
906
a role? Int. Arch. Occ. Env. Health 82, 551–556 (2009). 16 Hsing AW, McLaughlin JK, Zheng W, Gao
YT, Blot WJ. Occupation, physical activity, and risk of prostate cancer in Shanghai, People’s Republic of China. Cancer Causes Control. 5, 136–140 (1994). 17 Knutsson A, Damber L, Jarvholm B. Cancers in
concrete workers: results of a cohort study of 33,668 workers. Occup. Environ. Med. 57, 264–267 (2000). 18 Stocks T, Hergens MP, Englund A, Ye
W, Stattin P. Blood pressure, body size and
Future Oncol. (2014) 10(6)
prostate cancer risk in the Swedish Construction Workers cohort. Int. J. Cancer 127, 1660–1668 (2010). 19 Keller JE, Howe HL. Cancer in Illinois
construction workers: a study. Am. J. Ind. Med. 24, 223–230 (1993). 20 Moreira DM, Aronson WJ, Terris MK et al.
Cigarette smoking is associated with an increased risk of biochemical disease recurrence, metastasis, castration-resistant prostate cancer, and mortality after radical prostatectomy: results from the SEARCH database. Cancer 120, 197–204 (2014).
future science group
