Prognostic factors in 165 elderly colorectal cancer patients

Table 1 Results of univariate analysis

Variance	n	1 year survival rate (%)	3 year survival rate (%)	5 year survival rate (%)	P value
Age					0.0332
70-75	96	91.49	59.40	48.62
75-91	69	82.58	41.79	28.84
Treatment
Curative resection +	47	95.67	78.24	60.72
chemotherapy
Curative resection	71	95.65	62.62	55.01
Palliate resection +	21	71.43	11.11	0	< 0.005
chemotherapy
Palliate resection	6	50.00	0	0
Chemotherapy	16	75	0	0
Emergency surgery	4	0	0	0
Duke’s stage
A	8	100	75	37.5
B	35	100	79.16	64.57	< 0.005
C	72	97.16	70.55	56.05
D	50	63.88	6.74	0
Gross finding
Ulcer form	66	92.40	64.88	53.52
Projection form	57	92.88	58.86	49.15	< 0.005
Infiltration form	6	100	50	33.33
Type of histology
Tubular adenoma	130	91.41	55.33	44.77
Mucinous	23	73.91	29.12	23.29	0.0018
adenocarcinoma
Other types	12	75.0	56.25	0
Differentiation of tumor
High	10	100	74.07	44.44
Middle	123	95.87	57.84	47.55	< 0.005
Low	32	52.78	22.62	14.14
Nodular metastasis
No	43	100	79.62	67.24	0.0008
Yes	122	83.52	42.69	31.21

Table 2 Results of multivariate analysis for elderly colorectal cancer

Factors	Regression coefficient	Standard error	OR	OR 95%CI		P value
				Lower	Upper
Treatment method	2.028	0.356	7.603	3.782	15.284	0.000
Duke’s stage	0.648	0.295	0.523	0.293	0.933	0.028
Type of histology	-0.824	0.248	0.439	0.270	0.713	0.003
Differentiation of tumor	-0.850	0.246	0.427	0.264	0.692	0.016

Value: Resection + chemotherapy = 0, resection only = 1. Duke’s A + B stage = 0, Duke’s C + D stage = 1. Other type = 0, tubular adenoma = 1. Low differentiation = 0, middle and high differentiation = 1.