Polo-like kinase 1 expression is a prognostic factor in human colon cancer

Table 2 Correlation of PLK1 expression and selected tumor param-eters with patient prognosis

		Cases	Events	Mean survival(mo)	Standard error	Log-ranktest P
Age (yr)	≤65 yr	74	13	76.59	3.42	0.0142
	>65 yr	79	29	57.94	3.51
Dukes stage	A	35	4	70.27	3.18	<0.0001
	B	55	5	83.89	2.67
	C	50	23	48.26	4.28
	D	13	10	22.96	6.6
Tumor stage	T1	10	0	Not reached	–	0.0006
	T2	36	8	74.08	5.06
	T3	96	27	63.84	3.06
	T4	11	7	27	7.22
Nodal status	N0	91	11	81.93	2.34	<0.0001
	N1	30	10	55.94	5.17
	N2	32	21	28.74	3.97
Metastasis	Mx	140	32	73.19	2.68	<0.0001
	M1	13	10	22.96	6.6
Grade	G1	6	0	Not reached	–	0.0007
	G2	123	29	72.61	2.9
	G3	24	13	33.37	4.68
PLK1	Negative	51	7	74.13	2.9	0.006
(all cases)	Positive	102	35	63.75	3.66
PLK1	Negative	49	5	76.36	2.52
(locoregional disease)	Positive	91	27	67.77	3.66	0.0119