Introduction 1 2 3 4 5 6 8 9 10 11 APC TP53 KRAS 12 13 14 APC 8 15 KRAS 15 TP53 15 16 vice versa 17 18 19 20 21 KRAS 22 APC KRAS Materials and methods Study population 23 24 24 1 Fig. 1 a b c d e f g h  The first 2.3 years of follow up were excluded because of possible preclinical disease affecting exposure status and because of incomplete nationwide coverage of PALGA alone (i.e., not in combination with the NCR) in some of the municipalities included in the NLCS. Within this period, 83 subcohort members deceased or were diagnosed with cancer other than non-melanoma skin cancer, leaving 3,263 subcohort members for analysis. From 1989 to 1994, 929 incident cases with histologically confirmed colorectal cancer were identified within the entire cohort, of whom 819 could also be linked to a PALGA report of the lesion. The PALGA reports were used to identify and locate tumor tissues from eligible colorectal cancer patients in 54 pathology laboratories throughout the Netherlands. Cancers were classified according to site as follows, colon: cecum through sigmoid colon (ICD-O codes 153:0, 153.1, 153.2, 153.3, 153.4, 153.5, 153.6, 153.7), proximal colon (ICD-O codes 153.0, 153.1, 153.4, 153.5, 153.6), distal colon (ICD-O codes 153.2, 153,3, `53.7), rectosigmoid (ICD-O code 154.0), and rectum (ICD-O code 154.1). Tissue samples APC KRAS Since the rectosigmoid can be considered as a clinically applied term rather than an anatomically defined transitional zone between the colon and rectum, the 85 patients with a rectosigmoid tumor were excluded from data analysis. Moreover, the group of patients with a rectosigmoid tumor was too small for adequate stratified analysis. MLH1 expression analysis 2 2 1 APC APC 25 APC APC 25 26 APC  25 25 APC 25 APC APC 1 KRAS KRAS 27 KRAS 27 1 Exposure assessment 28 29 29 29 APC KRAS 1 30 31 2 Statistical analysis APC KRAS 1 APC APC + APC −  APC APC APC KRAS KRAS 22 KRAS APC KRAS KRAS KRAS 2 APC APC U APC 2 Incidence rate ratios (RR) and corresponding 95% confidence intervals (CI) for colon and rectal cancer patients were estimated according to quartiles of intake of fat variables, and one standard deviation increment of intake, using Cox proportional hazards regression models. In addition, associations were estimated for specific molecular endpoints of the tumors. 32 33 34 p Results 1 APC 1 APC 25 Table 1 Baseline dietary intake and other characteristics of the subcohort and colon and rectum cancer patients from The Netherlands cohort study  Subcohort n  p b n p b n p b a a APC  c APC  c APC  c APC   c N 2,948 374 54  274 127  73 57      Sex (%men) 48 56 41 0.04 52 56 0.49 64 67 0.79     Age (years) 61.3 ± 4.2 63.0 ± 4.0 62.8 ± 4.5 0.91 63.1 ± 4.0 62.7 ± 4.0 0.34 62.2 ± 4.4 62.6 ± 3.5 0.63 d     Total fat 83.8 ± 15.8 85.1 ± 14.7 84.1 ± 17.5 0.57 85.2 ± 15.0 84.8 ± 14.9 0.80 85.1 ± 14.2 86.7 ± 14.8 0.52     Saturated fat 33.2 ± 7.5 33.5 ± 6.6 33.3 ± 7.6 0.64 33.3 ± 6.7 33.5 ± 7.0 0.92 33.0 ± 5.8 35.5 ± 7.7 0.05 e 31.4 ± 7.0 31.9 ± 6.5 31.1 ± 7.5 0.45 31.8 ± 6.6 31.9 ± 6.6 0.98 31.8 ± 6.1 32.8 ± 6.2 0.37 f 17.3 ± 7.5 17.9 ± 7.5 17.4 ± 6.8 0.85 18.2 ± 7.3 17.8 ± 7.6 0.44 18.6 ± 8.7 16.5 ± 6.9 0.27     Linoleic acid 16.0 ± 7.5 16.7 ± 7.5 16.6 ± 7.0 0.76 17.0 ± 7.4 16.6 ± 7.7 0.36 17.5 ± 8.8 15.2 ± 7.2 0.15     Linolenic acid 1.3 ± 0.6 1.2 ± 0.5 1.3 ± 0.6 0.98 1.2 ± 0.5 1.3 ± 0.5 0.57 1.3 ± 0.6 1.3 ± 0.6 0.79 Other dietary factors     Fibre (g/day) 27.0 ± 8.2 24.5 ± 8.1 25.2 ± 7.1 0.13 26.7 ± 7.9 27.9 ± 8.1 0.20 28.1 ± 7.0 28.2 ± 9.0 0.78 g 10.1 ± 14.1 11.0 ± 14.8 10.7 ± 17.0 0.49 11.0 ± 14.9 11.3 ± 16.5 0.89 12.2 ± 14.9 14.5 ± 18.1 0.53     Fruit (g/day) 177.0 ± 118.0 178.8 ± 122.1 160.5 ± 137.7 0.07 169.7 ± 121.9 187.5 ± 132.2 0.11 197.4 ± 155.1 205.0 ± 118.3 0.21     Vegetables (g/day) 193.8 ± 82.2 191.3 ± 82.3 185.4 ± 73.8 0.80 187.9 ± 80.7 192.7 ± 85.2 0.71 186.3 ± 68.5 169.0 ± 122.2 0.69     Energy (kj/day) 8,028 ± 2,164 8,080 ± 2,059 7,505 ± 1,718 0.07 7,845 ± 1,899 8,335 ± 2,306 0.09 8,433 ± 1,924 8,449 ± 1,616 0.92 Other characteristics h 2 25.1 ± 3.1 25.6 ± 3.2 25.6 ± 3.5 0.57 25.5 ± 3.28 25.8 ± 3.1 0.30 25.3 ± 3.1 25.1 ± 2.8 0.92 i 6 13 9 0.49 11 11 0.98 10 11 0.86 Smoker (%)     Never 37 37 33  36 38  26 33      Ex-smoker 35 45 37  46 43  47 39      Current smoker 28 18 30 0.12 18 19 0.88 27 28 0.59 g     <30 min/day 21 21 22  19 26  17 26      30-60 min/day 32 33 22  33 28  28 32      60-90 min/day 21 21 19  22 18  24 18      >90 min/day 27 25 37 0.20 26 27 0.31 32 25 0.43 a MLH1 b p MLH1 APC c APC  APC APC d e f g h i 1 APC APC APC p  2 APC APC APC 2 p  APC p 2 APC Table 2 MLH1 APC Dietary fat intake Median intake (g/day) b Colon cancer Overall No MLH1 expression APC a APC  a Men Women Number of patients c c Number of patients c c Number of patients c c Number of patients c c Total fat     Q1 78.0 63.0 3,549 110 1.00 (reference) 11 1.00 (reference) 61 1.00 (reference) 40 1.00 (reference)     Q2 90.2 71.4 3,556 125 1.09 (0.82–1.44) 17 1.47 (0.69–3.14) 87 1.34 (0.94–1.90) 32 0.80 (0.49–1.28)     Q3 98.5 77.6 3,579 89 0.75 (0.55–1.01) 11 0.94 (0.40–2.17) 55 0.82 (0.56–1.21) 24 0.57 (0.33–0.96)     Q4 108.8 85.3 3,588 110 0.96 (0.72–1.28) 15 1.30 (0.59–2.86) 71 1.11 (0.77–1.59) 31 0.74 (0.46–1.20)     p d     0.29   0.82   0.71   0.13  e     1.00 (0.88–1.13)  1.21 (0.82–1.77)  1.04 (0.89–1.22)  0.93 (0.76–1.14) Saturated fat     Q1 28.9 23.9 3,567 99 1.00 (reference) 9 1.00 (reference) 59 1.00 (reference) 33 1.00 (reference)     Q2 33.7 27.8 3,550 120 1.20 (0.89–1.61) 14 1.48 (0.63–3.49) 84 1.38 (0.97–1.97) 30 0.94 (0.55–1.61)     Q3 38.3 30.9 3,583 115 1.11 (0.82–1.49) 19 1.93 (0.86–4.32) 73 1.15 (0.79–1.66) 33 1.01 (0.60–1.68)     Q4 45.8 36.6 3,571 100 0.94 (0.69–1.27) 12 1.25 (0.52–3.00) 58 0.90 (0.62–1.32) 31 0.89 (0.53–1.48)     p d     0.54   0.48   0.35   0.72  e     0.97 (0.87–1.08)  1.12 (0.82–1.51)  0.95 (0.83–1.09)  0.95 (0.79–1.14) f     Q1 28.2 22.4 3,546 98 1.00 (reference) 11 1.00 (reference) 56 1.00 (reference) 31 1.00 (reference)     Q2 33.2 26.0 3,546 122 1.20 (0.89–1.61) 14 1.15 (0.52–2.53) 79 1.33 (0.92–1.91) 36 1.18 (0.72–1.95)     Q3 36.9 28.9 3,580 113 1.12 (0.83–1.52) 14 1.15 (0.52–2.54) 76 1.30 (0.89–1.89) 31 1.03 (0.60–1.77)     Q4 42.5 33.1 3,600 101 0.99 (0.73–1.34) 15 1.25 (0.58–2.71) 63 1.08 (0.74–1.57) 29 0.90 (0.54–1.52)     p d     0.79   0.59   0.80   0.57  e     0.99 (0.88–1.12)  1.04 (0.73–1.46)  1.01 (0.87–1.17)  0.98 (0.81–1.18) g     Q1 11.6 8.8 3,507 91 1.00 (reference) 8 1.00 (reference) 49 1.00 (reference) 32 1.00 (reference)     Q2 16.0 12.4 3,562 118 1.37 (1.02–1.86) 16 2.03 (0.86–4.81) 73 1.55 (1.06–2.28) 33 1.13 (0.68–1.89)     Q3 20.9 16.2 3,618 113 1.24 (0.91–1.68) 16 2.00 (0.84–4.76) 78 1.57 (1.07–2.31) 30 0.96 (0.57–1.62)     Q4 29.3 22.5 3,580 112 1.21 (0.89–1.63) 14 1.75 (0.72–4.24) 74 1.47 (1.01–2.16) 32 0.98 (0.59–1.63)     p d     0.38   0.26   0.06   0.79  e     1.03 (0.94–1.14)  1.07 (0.82–1.38)  1.09 (0.97–1.23)  1.00 (0.84–1.19) Linoleic acid     Q1 10.0 7.5 3,509 86 1.00 (reference) 8 1.00 (reference) 49 1.00 (reference) 26 1.00 (reference)     Q2 14.8 11.2 3,586 122 1.49 (1.10–2.02) 13 1.66 (0.69–3.98) 71 1.50 (1.02–2.21) 40 1.65 (0.99–2.76)     Q3 19.5 14.9 3,599 112 1.32 (0.97–1.79) 17 2.14 (0.91–5.00) 82 1.68 (1.15–2.45) 25 1.00 (0.57–1.76)     Q4 28.0 21.2 3,574 114 1.30 (0.96–1.77) 16 2.02 (0.86–4.76) 72 1.44 (0.99–2.11) 36 1.35 (0.80–2.28)     p d     0.20   0.08   0.05   0.65  e     1.06 (0.96–1.17)  1.15 (0.90–1.48)  1.12 (0.99–1.26)  1.02 (0.86–1.21) Linolenic acid     Q1 0.8 0.6 3,518 107 1.00 (reference) 11 1.00 (reference) 68 1.00 (reference) 31 1.00 (reference)     Q2 1.2 0.9 3,574 104 0.95 (0.70–1.30) 17 1.32 (0.60–2.89) 72 0.99 (0.68–1.43) 24 0.84 (0.47–1.49)     Q3 1.5 1.2 3,571 117 1.10 (0.82–1.48) 11 0.91 (0.40–2.10) 62 0.89 (0.62–1.29) 43 1.48 (0.91–2.40)     Q4 2.0 1.6 3,604 106 1.01 (0.76–1.36) 15 1.32 (0.61–2.84) 72 1.08 (0.76–1.53) 29 0.97 (0.57–1.65)     p d     0.68   0.73   0.82   0.52  e     0.98 (0.89–1.09)  1.07 (0.79–1.44)  0.97 (0.85–1.10)  1.01 (0.86–1.19) a APC  APC APC b c d p e 1 f g 3 APC APC p 3 APC Table 3 APC Dietary fat intake Median intake (g/day) b Rectal cancer Overall APC a APC  a Men Women Number of patients c c Number of patients c c Number of patients c c Total fat     Q1 78.0 63.0 3,549 43 1.00 (reference) 24 1.00 (reference) 15 1.00 (reference)     Q2 90.2 71.4 3,556 39 0.89 (0.56–1.39) 17 0.70 (0.37–1.34) 12 0.79 (0.36–1.70)     Q3 98.5 77.6 3,579 33 0.74 (0.46–1.19) 16 0.65 (0.33–1.26) 14 0.91 (0.43–1.90)     Q4 108.8 85.3 3,588 38 0.87 (0.55–1.36) 15 0.60 (0.31–1.16) 16 1.06 (0.51–2.19)     p d     0.42   0.13   0.80  e     0.91 (0.76–1.09)  0.84 (0.65–1.08)  0.94 (0.69–1.28) Saturated fat     Q1 28.9 23.9 3,567 43 1.00 (reference) 23 1.00 (reference) 14 1.00 (reference)     Q2 33.7 27.8 3,550 34 0.80 (0.49–1.29) 18 0.81 (0.42–1.56) 12 0.87 (0.39–1.91)     Q3 38.3 30.9 3,583 44 1.02 (0.66–1.59) 21 0.92 (0.49–1.73) 12 0.86 (0.40–1.88)     Q4 45.8 36.6 3,571 33 0.74 (0.46–1.18) 11 0.46 (0.22–0.97) 19 1.30 (0.65–2.63)     p d     0.38   0.07   0.47  e     0.95 (0.81–1.12)  0.81 (0.65–1.02)  1.16 (0.89–1.50) f     Q1 28.2 22.4 3,546 44 1.00 (reference) 23 1.00 (reference) 15 1.00 (reference)     Q2 33.2 26.0 3,546 31 0.70 (0.44–1.13) 18 0.79 (0.41–1.49) 9 0.62 (0.27–1.43)     Q3 36.9 28.9 3,580 40 0.91 (0.58–1.44) 15 0.67 (0.34–1.33) 20 1.36 (0.67–2.78)     Q4 42.5 33.1 3,600 39 0.88 (0.56–1.37) 17 0.72 (0.38–1.36) 13 0.88 (0.40–1.90)     p d     0.82   0.28   0.76  e     0.94 (0.78–1.12)  0.85 (0.67–1.08)  1.00 (0.76–1.33) g     Q1 11.6 8.8 3,507 45 1.00 (reference) 17 1.00 (reference) 21 1.00 (reference)     Q2 16.0 12.4 3,562 32 0.74 (0.46–1.18) 19 1.17 (0.60–2.28) 10 0.49 (0.23–1.07)     Q3 20.9 16.2 3,618 39 0.86 (0.55–1.34) 16 0.94 (0.47–1.88) 16 0.76 (0.39–1.48)     Q4 29.3 22.5 3,580 38 0.82 (0.53–1.29) 21 1.20 (0.63–2.29) 10 0.47 (0.22–1.00)     p d     0.53   0.73   0.11  e     0.98 (0.83–1.16)  1.06 (0.84–1.34)  0.78 (0.60–1.03) Linoleic acid     Q1 10.0 7.5 3,509 39 1.00 (reference) 18 1.00 (reference) 18 1.00 (reference)     Q2 14.8 11.2 3,586 39 1.03 (0.65–1.64) 17 0.98 (0.50–1.92) 14 0.80 (0.40–1.63)     Q3 19.5 14.9 3,599 35 0.90 (0.56–1.44) 16 0.90 (0.45–1.79) 15 0.84 (0.42–1.68)     Q4 28.0 21.2 3,574 41 1.03 (0.65–1.62) 22 1.19 (0.63–2.24) 10 0.54 (0.25–1.18)     p d     0.95   0.65   0.15  e     0.99 (0.84–1.17)  1.09 (0.86–1.38)  0.79 (0.60–1.04) Linolenic acid     Q1 0.8 0.6 3,518 42 1.00 (reference) 18 1.00 (reference) 18 1.00 (reference)     Q2 1.2 0.9 3,574 38 0.92 (0.57–1.48) 20 1.16 (0.58–2.31) 10 0.55 (0.25–1.24)     Q3 1.5 1.2 3,571 36 0.87 (0.55–1.38) 15 0.87 (0.43–1.75) 13 0.72 (0.35–1.48)     Q4 2.0 1.6 3604 38 0.92 (0.58–1.44) 20 1.13 (0.60–2.14) 16 0.90 (0.45–1.80)     p d     0.68   0.93   0.91  e     0.95 (0.81–1.12)  0.98 (0.77–1.24)  1.03 (0.81–1.31) a APC  APC APC b c d p e 1 f g APC KRAS 22 KRAS p APC p APC 4 KRAS 4 p p Table 4 APC KRAS Dietary fat intake e Colon cancer a b APC c KRAS d   Number of patients f f Number of patients f f Number of patients f f Number of patients f f g Q1 3,507 39 1.00 (reference) 6 1.00 (reference) 18 1.00 (reference) 4 1.00 (reference) Q2 3,562 44 1.15 (0.73–1.81) 14 2.48 (0.94–6.54) 21 1.31 (0.68–2.53) 14 3.76 (1.21–11.69) Q3 3,618 45 1.10 (0.70–1.73) 11 1.89 (0.69–5.16) 15 0.86 (0.43–1.74) 19 5.00 (1.67–14.99) Q4 3,580 35 0.86 (0.54–1.38) 10 1.72 (0.61–4.81) 13 0.70 (0.34–1.45) 28 6.74 (2.36–19.51) p h   0.51   0.48   0.19   ≤0.001  i   0.96 (0.82–1.13)  1.01 (0.72–1.40)  0.90 (0.71–1.14)  1.40 (1.17–1.68) Linoleic acid Q1 3,509 38 1.00 (reference) 7 1.00 (reference) 14 1.00 (reference) 4 1.00 (reference) Q2 3,586 45 1.20 (0.77–1.90) 10 1.51 (0.58–0.93) 26 2.03 (1.03–3.99) 15 4.06 (1.32–12.46) Q3 3,599 45 1.15 (0.73–1.81) 14 2.08 (0.84–5.19) 13 0.99 (0.46–2.13) 21 5.61 (1.88–16.68) Q4 3,574 35 0.90 (0.56–1.44) 10 1.49 (0.56–3.97) 14 0.97 (0.46–2.06) 25 6.02 (2.09–17.41) p h   0.62   0.30   0.38   ≤0.001  i   0.98 (0.84–1.15)  1.08 (0.79–1.49)  0.91 (0.73–1.14)  1.41 (1.18–1.69) a APC KRAS b APC KRAS c APC KRAS d KRAS APC e f g h p i 1 APC KRAS p Discussion APC KRAS APC 35 43 35 38 41 42 APC 38 APC KRAS APC KRAS 41 KRAS 22 KRAS 35 42 40 35 39 41 43 37 40 42 35 37 42 KRAS 22 KRAS APC KRAS 27 18 19 21 KRAS 7 8 15 33 KRAS APC KRAS APC 25 APC KRAS APC KRAS KRAS APC KRAS APC KRAS TP53 44 TP53 4 16 KRAS KRAS APC