Table 2.

Association between circumcision status, age at circumcision and prostate cancer, overall and by aggressiveness of cancer, PROtEuS, Montréal, Québec, Canada, 2005–2009

	All subjects (1555 cases and 1586 controls)			Less aggressive prostate cancer†‡ (N = 1127 cases)		More aggressive prostate cancer†‡ (N = 423 cases)
	Cases n (%)	Controls n (%)	OR (95% CI)*	Cases n (%)	OR (95% CI)*	Cases n (%)	OR (95% CI)*
Circumcision status:
No	963 (61.9)	949 (59.8)	1.00	693 (61.5)	1.00	266 (62.9)	1.00
Yes	592 (38.1)	637 (40.2)	0.89 (0.76–1.04)	434 (38.5)	0.90 (0.76–1.07)	157 (37.1)	0.86 (0.69–1.09)
Age at circumcision, years§
Not circumcised	963 (63.4)	949 (60.7)	1.00	693 (62.8)	1.00	266 (64.7)	1.00
<1	408 (26.8)	435 (27.8)	0.86 (0.72–1.04)	309 (28.0)	0.91 (0.75–1.10)	98 (23.8)	0.77 (0.59–1.01)
1–8	35 (2.3)	49 (3.1)	0.88 (0.54–1.44)	22 (2.0)	0.76 (0.44–1.33)	13 (3.2)	1.18 (0.61–2.30)
9–20	46 (3.0)	45 (2.9)	1.12 (0.71–1.78)	31 (2.8)	1.06 (0.64–1.76)	15 (3.7)	1.28 (0.68–2.39)
21–35	48 (3.2)	46 (2.9)	0.89 (0.57–1.40)	35 (3.2)	0.89 (0.55–1.46)	13 (3.2)	0.91 (0.47–1.75)
≥36	20 (1.3)	40 (2.6)	0.55 (0.30–0.98)	14 (1.3)	0.54 (0.28–1.05)	6 (1.5)	0.56 (0.23–1.37)

^*Adjusted for age at diagnosis for cases or interview for controls, ancestry, family history of prostate cancer, ever had STI, prostate cancer screening within the last 2 years, and highest educational level achieved.

^†Less aggressive prostate cancer refers to Gleason scores ≤7(3 + 4) and more aggressive prostate cancer refers to Gleason scores ≥7(4 + 3).

^‡Gleason scores were missing for five cases.

^§22 circumcised controls and 35 circumcised cases did not know their age at circumcision.