Comorbidities as predictors of incidental prostate cancer after Holmium laser enucleation of the prostate: diabetes and high-risk cancer

An association between diabetes mellitus (DM) and cancer has long been speculated, but no conclusive evidence has been obtained. We prospectively examined the association between a history of DM and subsequent risk of cancer in the Japan Public Health Center-Based Prospective Study. A total of 97 771 general Japanese persons (46 548 men and 51 223 women) aged 40 to 69 years who responded to the baseline questionnaire, from January 1990 to December 1994, were followed up for cancer incidence through December 31, 2003. At baseline, 6.7% of men and 3.1% of women had a history of DM. A total of 6462 cases of newly diagnosed cancer were identified. In men, a 27% increase in the risk of total cancer incidence was observed in those with a history of DM (n = 3907 [366 with DM]; hazard ratio [HR], 1.27; 95% confidence interval [CI], 1.14-1.42). The HR was especially high for those with cancer of the liver (n = 312 [52 with DM]; HR, 2.24; 95% CI, 1.64-3.04), pancreas (n = 118 [16 with DM]; HR, 1.85; 95% CI, 1.07-3.20), and kidney (n = 99 [13 with DM]; HR, 1.92; 95% CI, 1.06-3.46). We also observed a moderately increased risk of colon cancer (n = 491 [46 with DM]; HR, 1.36; 95% CI, 1.00-1.85) and of stomach cancer with borderline significance (n = 977 [87 with DM]; HR, 1.23; 95% CI, 0.98-1.54). In women, a borderline significant increase in risk was observed for the incidence of total cancer (n = 2555 [104 with DM]; HR, 1.21; 95% CI, 0.99-1.47), while statistical significance was observed for the incidence of stomach cancer (n = 362 [20 with DM]; HR, 1.61; 95% CI, 1.02-2.54) and liver cancer (n = 120 [10 with DM]; HR, 1.94; 95% CI, 1.00-3.73) and borderline significance was observed for the incidence of ovarian cancer (n = 74 [5 with DM]; HR, 2.42; 95% CI, 0.96-6.09). Patients with DM drawn from the general Japanese population may be at increased risk of total cancer and of cancer in specific sites. Show more

Studies on the relationship between obesity and prostate cancer incidence are inconsistent. In part, this inconsistency may be due to a differential effect of obesity on low-grade and high-grade cancer or confounding of the association of obesity with prostate cancer risk by diabetes. We investigated the associations of obesity and diabetes with low-grade and high-grade prostate cancer risk. Data were from 10,258 participants (1,936 prostate cancers) in the Prostate Cancer Prevention Trial who all had cancer presence or absence determined by prostate biopsy. Multiple logistic regression was used to model the risk of total prostate cancer, and polytomous logistic regression was used to model the risk of low-grade and high-grade prostate cancer. Compared with men with body mass index or =30) had an 18% [odds ratio (OR), 0.82; 95% confidence interval (95% CI), 0.69-0.98] decreased risk of low-grade prostate cancer (Gleason or =7) or, alternatively, a 78% (OR, 1.78; 95% CI, 1.10-2.87) increased risk defining high-grade cancer as Gleason sum 8 to 10. Diabetes was associated with a 47% (OR, 0.53; 95% CI, 0.34-0.83) reduced risk of low-grade prostate cancer and a 28% (OR, 0.72; 95% CI, 0.55-0.94) reduced risk of high-grade prostate cancer. Associations of obesity or diabetes with cancer risk were not substantially changed by mutually statistical controlling for each other. Obesity increases the risk of high-grade but decreases the risk of low-grade prostate cancer, and this relationship is independent of the lower risk for prostate cancer among men with diabetes. Show more

Obesity has been associated with aggressive prostate cancer. The extent of this association, which varies by stage and grade, remains unclear. The role of recent weight change had not been previously examined. We examined body mass index (BMI) and weight change in relation to incident prostate cancer by disease stage and grade at diagnosis among 69,991 men in the Cancer Prevention Study II Nutrition Cohort. Participants provided information on height and weight in 1982, and again at enrollment in 1992. During follow-up through June 30, 2003 (excluding the first 2 years of follow-up), we documented 5,252 incident prostate cancers. Cox proportional hazards models were used to estimate rate ratios (RR) and 95% confidence intervals (95% CI). The association between BMI in 1992 and risk of prostate cancer differed by stage and grade at diagnosis. BMI was inversely associated with risk of nonmetastatic low-grade prostate cancer (RR, 0.84; 95% CI, 0.66-1.06), but BMI was positively associated with risk of nonmetastatic high-grade prostate cancer (RR, 1.22; 95% CI, 0.96-1.55) and risk of metastatic or fatal prostate cancer (RR, 1.54; 95% CI, 1.06-2.23). Compared with weight maintenance, men who lost >11 pounds between 1982 and 1992 were at a decreased risk of nonmetastatic high-grade prostate cancer (RR, 0.58; 95% CI, 0.42-0.79). Obesity increases the risk of more aggressive prostate cancer and may decrease either the occurrence or the likelihood of diagnosis of less-aggressive tumors. Men who lose weight may reduce their risk of prostate cancer. Show more