Table 4.

Characteristics of colonoscopy prior to diagnosis of colorectal cancer

		Sub- ject	Age	Location of CRC	Stage	Colonoscopy Number before Dx	Interval before Dx (mo)	Prep Quality	Cecum Reached (Y/N)	Classification	Recommended Surveillance Interval (years)	CRC in segment of colon with prior polypectomy	Suspected Etiology of Interval CRC
Within Surveillance Interval	Interval CRC = Within 5 Years of Colonoscopy	1	63	HF/TV	IV	7*	14	Fair	Y	HRA	1	Y	Inc/Bio
		2	69	HF	I	2*	17	Good	Y	HRA	1	Y	Inc
		3	65	TV	-	2	27	-	-	HRA	2	-	Miss/Bio?
		4	78	Rectum	IIIB	2*	7	Adequate	Y	HRA	3	N	Miss
		5	67	HF/Asc	IV	2*	35	Good	Y	HRA	3	Y	Inc
		6	69	Rectum	IIIB	1*	38	Fair	Y	HRA	3	N	Miss
		7	81	Rectosig	IIA	1*	30	-	N	LRA	5	N	Miss
		8	63	Rectum	IIIB	1*	47	Good	Y	LRA	5	Y	Inc
		9	74	Cecum	IIA	2*	64	Good	Y	h/o HRA	5	N	Miss
		10	84	Cecum	IIIB	1	54	-	-	NORM	10		Miss
		11	83	Rectum	I	1	54	-	-	NORM	10		Miss
		12	60	Asc	IV	1	54	-	Y	NORM	10		Miss
		13	87	Cecum	IIA	3*	46	Excellent	Y	h/o HRA	None (given age)	N	Miss
	>5Y	14	56	Rectum	IIIA	1*	69	Good	Y	NORM	10
		15	61	Sigmoid	I	1	101	-	-	NORM	10
		16	83	Restosig	I	1	106	-	-	NORM	10
Outside Surveillance	≤5	17	74	Desc	I	2*	44	Good	Y	HRA	1	Y
		18	80	Sigmoid	IIA	2*	51	Good	Y	h/o HRA	1	Y
	>5 years	19	77	Rectum	III	2*	83	Adequate	Y	HRA	1	N
		20	74	Rectum	IIA	2	68	-	-	HRA	3	Y
		21	79	TV	IIA	1*	78	Good	Y	HRA	3	N
		22	81	TV	II	2*	120	-	-	LRA	5	N
		23	80	Cecum	IIA	1*	126	-	-	HRA	5	N
	Unk	24	83	Rectosig	IIA	3	55	-	-	-	-	-
		25	67	Asc	IIA	2	33	-	-	-	-	-

^*one or more colonoscopy performed at SFVA

- indicates missing data

Abbreviations: Unk = Unknown surveillance recommendation, Rectosig=rectosigmoid colon; Desc= descending colon, TV= transverse colon, HF= hepatic flexure, Asc=ascending colon; h/o = history of, HRA = high risk adenoma, LRA=low risk adnemoa, NORM=normal colonoscopy, Inc = possible incomplete polypectomy, Bio = possible biological factors, Miss = possible missed lesion