Table 1. Characteristics of the study population (n=253).

	Surgical Quality Indicator					Total Patients
	Number of Lymph Nodes
	<12 (n=48)		≥12 (n=205)
Characteristic	n=	%	n=	%	p=	n=	%
Gender					0.99
Female	26	19.3	109	80.7		135	53.4
Male	22	18.6	96	81.4		118	46.6
Mean age (years) ± Std Dev	71.4 ± 11.7		67.9 ± 13.0		0.096	68.6 ± 12.8
Body Mass Index (kg/m2)	25.6 ± 3.9		25.8 ± 4.5		0.79	25.7 ± 4.4
Primary Tumor Location					<0.001
Colon	33	15.2	184	84.8		217	85.8
Rectum	15	41.7	21	58.3		36	14.2
Extent of resection					0.036
Segment	47	20.7	180	79.3		227	89.7
> Segment	1	3.8	25	96.2		26	10.3
Operation Category					0.76
Open	44	18.7	191	81.3		235	92.9
Laparoscopic	4	22.2	14	77.8		18	7.1
Mean tumor size (cm) ± Std Dev	3.0 ± 1.9		3.9 ± 1.8		0.009	3.8 ± 1.9
Tumor Stage Category					0.023
T1/T2	18	26.1	51	73.9		69	28.7
T3/T4	23	13.5	148	86.5		171	71.3
Lymph-vascular Invasion					0.58
Absent	38	17.6	178	82.4		216	89.3
Present	3	11.5	23	88.5		26	10.7
Mean number of nodes ± Std Dev	8.0 ± 2.3		22.4 ± 11.1		<0.001	19.6 ± 11.5
Median positive nodes (range)	0 (0-5)		0 (0-40)		0.016	0 (0-40)
Nodal Stage Category					0.016
N0	38	22.6	130	77.4		168	66.4
N1	9	15.3	50	84.7		59	23.3
N2	1	3.8	25	96.2		26	10.3
AJCC Stage					<0.001
I	24	35.3	44	64.7		68	26.9
II	14	14.0	86	86.0		100	39.5
III (ultrastaged N0 to N1mi, n=9)	10	11.8	75	88.2		85	33.6
Nodal Disease Volume					0.019
N0(i-)	33	23.4	108	76.6		141	55.7
N0(i+); ≤ 0.2 mm	5	18.5	22	81.5		27	10.7
N1mi; >0.2 to <2 mm	3	33.3	6	66.7		9	3.6
N1/2; ≥ 2 mm	7	9.2	69	90.8		76	30.0