Thromboembolic events following surgery for prostate cancer.

BACKGROUND: Prostate cancer (PCa) and surgery are both associated with increased risk of thromboembolic diseases (TED). OBJECTIVE: We assessed risk of TED among men undergoing different types of urologic surgery. DESIGN, SETTING, AND PARTICIPANTS: Using the Prostate Cancer Database Sweden (PCBaSe) Sweden, we identified all men (n=45 065) undergoing pelvic lymph node dissection (PLND), radical prostatectomy (RP) with or without PLND, orchiectomy due to PCa, or a transurethral resection of the prostate (TURP). We identified a comparison cohort from the population. OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS: Main outcomes were deep venous thrombosis (DVT) and pulmonary embolism (PE) as primary diagnoses in the National Patient Register or Cause of Death Register (2002-2010). We calculated hazard ratios (HR) and 95% confidence intervals (CI) using multivariable Cox proportional hazards models. RESULTS AND LIMITATIONS: All surgical procedures were associated with increased risk of TED; laparoscopic and open RP with a PLND were the most strongly associated with TED (HR for PE: 8.1 [95% CI, 2.9-23.0] and 7.8 [95% CI, 4.9-13], respectively). For surgery including a PLND, the risk increased during the second half of the first postoperative month. The HR for PE after TURP in men with PCa was 3.0 (95% CI, 1.8-5.1). Patients with a history of TED had a strongly increased risk of TED (HR for DVT: 4.5; 95% CI, 2.6-8.0). A limitation is lack of information on TED prophylaxis, but its use was standardized during the study period for RP and PLND. Other limitations are lack of information on extent of PLND and lifestyle factors. CONCLUSIONS: Surgeries for PCa, including TURP, are associated with hospitalization for TED. Patients with a history of TED and patients undergoing a PLND were at highest risk. The largest risk was observed from days 14 to 28 postoperatively. Thus, our results suggest that prophylactic measures may be beneficial during the first 4 wk in these patients.

Association of frequent consumption of fatty fish with prostate cancer risk is modified by COX-2 polymorphism.

Dietary intake of marine fatty acids from fish may protect against prostate cancer development. We studied this association and whether it is modified by genetic variation in cyclooxygenase (COX)-2, a key enzyme in fatty acid metabolism and inflammation. We assessed dietary intake of fish among 1,499 incident prostate cancer cases and 1,130 population controls in Sweden. Five single nucleotide polymorphisms (SNPs) were identified and genotyped in available blood samples for 1,378 cases and 782 controls. Odds ratios (OR) and 95% confidence intervals (CI) were estimated by multivariate logistic regression. Multiplicative and additive interactions between fish intake and COX-2 SNPs on prostate cancer risk were evaluated. Eating fatty fish (e.g., salmon-type fish) once or more per week, compared to never, was associated with reduced risk of prostate cancer (OR: 0.57, 95% CI: 0.43-0.76). The OR comparing the highest to the lowest quartile of marine fatty acids intake was 0.70 (95% CI: 0.51-0.97). We found a significant interaction (p < 0.001) between salmon-type fish intake and a SNP in the COX-2 gene (rs5275: +6365 T/C), but not with the 4 other SNPs examined. We found strong inverse associations with increasing intake of salmon-type fish among carriers of the variant allele (OR for once per week or more vs. never = 0.28, 95% CI: 0.18-0.45; p(trend) < 0.01), but no association among carriers of the more common allele. Frequent consumption of fatty fish and marine fatty acids appears to reduce the risk of prostate cancer, and this association is modified by genetic variation in the COX-2 gene.