Table 5.

Comparison of treatment background by HER2 expression

Treatment	HER2		P‐values
	Negative	Positive
Surgery			0.2454
Pancreaticoduodenectomy	35	46
Distal pancreatectomy	14	27
Total pancreatectomy	1	6
Chemotherapy			0.1351
None	29	32
Adjuvant oral 5‐FU derivative	17	30
Adjuvant intravenous gemcitabine	2	9
Neoadjuvant + adjuvant intravenous 5‐FU	2	8
Intraoperative radiotherapy			0.8021
Not done	44	67
Done	6	12
External radiotherapy			0.6989
Not done	45	68
Done	5	11

P‐values were examined by χ²‐test.