Table 1.

Epidemiological studies of colonic aberrant crypt foci.

Study	n	Patients	Tissue Source	ACF Density or number	Subject sampling method
Roncucci et al., (8) Toronto, Canada	27	5 FAP 12 CRC 10 BD	Surgery	Mean no. ACF per cm2 FAP = 19.9* CRC = 0.37 BD = 0.18 * P <0.01 FAP versus each group	Not described
Roncucci et al., (48) Italy	58	All CRC: 32 high risk area 26 low risk area	Surgery	All patients = 0.103 per cm2 Higher ACF density in high risk compared to low risk region (P = 0.001)	Not described
Takayama et al., (49) Japan	350	171 Normal 131 Adenoma  48 CRC Plus, 20 on prospective Suldinac Study	Magnifying colonoscopy lower rectum Full exam (n=3)	Median no. ACF   Normal = 1*   Adenoma = 5**   CRC = 26   * P < 0.001 versus adenoma   **P < 0.001 versus CRC	Patients were persons referred for colonoscopy at a hospital in Japan. The reasons for the referrals are not given. At exam, 49 had CRC, 142 had adenoma, and 179 had neither (called ‘normal’)
Shpitz et al., (50) Tel Aviv, Israel	93	76 CRC 17 BD	Surgery	Mean no. ACF per cm2 Age group:*   < 50 + 0.076   51-60= 0.074   61-69 = 0.099   70+ = 0.120   * P = NS Significantly more ACFs in CRC than BD CRC: More ACFs in distal versus proximal colon (P=0.01)	Not described
Bouzourene et al., (51) Switzerland	37	26 CRC 4 Adenoma 7 BD	Surgery	Median no. ACF per cm2   CRC = 0.032   Adenoma = 0.011   BD = 0.130	Not described
Nascimbeni et al., (52) Italy	103	76 CRC 27 diverticular disease (DD)	Surgery	Mean no. ACF per cm2   CRC = 0.200*   DD = 0.070   * P <0.05	Not described
Nascimbeni et al. (53) Italy	96	55 sigmoid cancer 41 diverticular disease	Surgery	Mean number ACF  CRC = 9.1  DD = 3.7 Mean crypt count not different	Not described
Adler et al., (54) Minnesota, USA	90	30 Normal 30 Adenoma 30 CRC All with indication for colonoscopy	Magnifying colonoscopy distal 10 cm	Mean no. ACF per patient   Normal = 5.0   Adenoma = 6.9   CRC = 9.9	Patients selected from the ‘daily colonoscopy list with selection based on the indication for the procedure’. 30 were selected because they were known to have CRC and this was to be their preoperative exam; 30 were known to have adenoma; 30 were not known to have either of these, but were referred for exam due to a symptom. Method of selection among these groups is not given.
Hurlstone et al., (55) United Kingdom	869	574 Normal 281 Adenoma 14 CRC All with indication for colonoscopy	Magnifying colonoscopy distal 10 cm Entire colon examined for CRC and adenomas	Median no. ACF per patient   Normal = 1   Adenoma = 9   CRC = 38	Sampling frame was all 2,559 patients receiving a colonoscopy performed by one endoscopist between January, 2000 and January, 2004 from a single hospital in Sheffield, England. Reasons for exam referral are given. Exclusion criteria are stated, leaving 1,000 eligible. 869 of these were included in the analyses
Rudolph et al., (56) Seattle, USA	32	8 Normal 24 Elective* 31 Males  1 Female * Indications: polyps, visible bleeding, occult blood, family history of CRC, personal CRC	Magnifying colonoscopy distal 14 cm	Median no. ACF per patient: 7.0 Older patients (70+) tended to have more ACFs (P=0.06) First 15 patients had up to 8 ACF counted and sampled for histology. Remaining 17 patients had all ACF counted but none sampled for histology	U.S. veterans aged 50 to 80 were eligible. 24 recruited from VA Health System for symptoms, with another 8 as ‘volunteers’.
Moxon et al. (57) Chicago	83	Screening colonoscopy 61 African- American 15 Euro-American 7 Latino-American	Magnifying chromendoscopy distal 15 cm	ACF number Synchronous normal colon = 12.6 Synchronous advanced neoplasia = 19.3 Tobacco 0 pack-years = 9.4 1-15 = 13.3 16-29 = 15.2 30+ = 19.4 significant increase with age	83 asymptomatic patients in Chicago. Not clear how these were selected from those who were eligible.
Seike et al. (58) Chiba, Japan	386	Referred for colonoscopy for a wide variety of symptoms	Chromendoscopy distal 15 cm	ACF number significantly predicted synchrounous advanced neoplasm in the colon and also in the rectum	386 patients scheduled for colonoscopy for a symptom were selected prospectively. Not explicitly stated, it appears all eligible patients were recruited.
Stevens et al., (59) Connecticut, USA	103	family history = 43 history of adenoma = 34 screening exam, average risk = 17	Magnifying, close focus colonoscopy distal 20 cm	Mean no. ACF per patient   family history = 9.0*   Px hist adenoma = 7.5**   screening, average risk = 4.4   * P = 0.01   ** P = 0.05	86 patients scheduled for either screening or surveillance colonoscopy who answered ‘yes’ to a family history of CRC, or to a personal history of adenoma or CRC 17 patients who answered ‘no’ to these same questions. Convenience sample from a larger number who would have been eligible.

Defined as percent of patients with at least 1 ACF.

Abbreviations:

FAP = Familial adenomatous polyposis

CRC= Colorectal cancer

BD= Benign disease

DD = Diverticular disease

NS = Non-signficant