Table 1. Comparison of basic disease characteristics and pathological types of breast cancer between HER-2 negative and positive groups.

Characteristics	HER-2 negative group (n=31)	HER-2 positive group (n=39)	t/χ2 value	P value
Size of breast lesion (mm)	21.66±10.33	21.99±10.45	10.654	0.52
Age (years)	55.29±11.87	56.15±12.43	11.654	0.66
Pathology			0.154	0.69
Invasive ductal carcinoma	26	34
Ductal carcinoma in situ	5	5

Data are expressed as mean ± standard deviation or number. HER-2, human epidermal growth factor receptor-2.