Significance of HER2 protein expression and HER2 gene amplification in colorectal adenocarcinomas

Table 5 Overall survival based on clinicopathological features

Clinicopathological features	Patients	Events	Median survival (95%CI), mo	P-value
Gender				0.707
Male	640	144	NA
Female	418	100	NA
Age (yr)
≤ 60	522	116	NA	0.591
> 60	536	128	NA
≤ 65	661	138	NA	0.027
> 65	397	106	NA
Tumor site				0.457
Colon	568	133	NA
Rectal	490	111	NA
Tumor grade				0.000
1-2	839	176	NA
3	219	68	NA
Histology				0.000
Tubular	971	205	NA
Mucinous/ Other types	87	39	54.90
Lymph node metastasis				0.000
No	562	61	NA
Yes	496	183	NA
Tumor stage				0.000
I-II	198	13	NA
III-IV	860	231	NA
HER2 protein overexpression by IHC
IHC (-)	935	221	NA	0.220
IHC (+)	123	23	NA
HER2 gene amplification by FISH
Positive	1022	234	NA	0.458
Negative	36	10	NA

NA: Because the overall survival rates of these patients were more than 50%, we didn’t get the median survival time. HER2: Human epidermal growth factor receptor 2; FISH: Fluorescence in situ hybridization; IHC: Immunohistochemical staining.