Re-evaluation of classical prognostic factors in resectable ductal adenocarcinoma of the pancreas

Table 5 Prognostic role of perineural invasion

Ref.	Year	n	Detection rate (%)	Median OS with PNI (mo)	Survival model	HR (95%CI)	P value
Kondo et al[36]	2015	209	197 (94)	15	Multivariable	No of PNIs:	< 0.001
						< 14: 1
						14-40: 1.96 (1.01-3.93)
						> 40: 5.81 (3.17-11.35)
Fouquet et al[34]	2014	166	133 (81)	NR	Multivariable	2.77 (1.40-5.26)	0.001
Chatterjee et al[80]	2012	212	123 (58)	29	Multivariable	1.70 (1.18-2.45)	0.005
Takahashi et al[81]	2012	110	56 (51)	NR	Multivariable	2.48 (1.11-5.52)	0.026
Sahin et al[82]	2012	544	473 (87)	29	Multivariable	1.60 (1.08-2.36)	0.019
Robinson et al[59]	2012	134	128 (96)	NR	Multivariable	5.52 (NR)	< 0.050
Kanda et al[63]	2011	429	148 (34)	NR	Multivariable	1.72 (1.15-2.58)	< 0.001
Shimada et al[35]	2011	153	146 (94)	7 (DFS)	Multivariable	2.19 (1.36-3.52)	0.001
Murakami et al[64]	2010	103	31 (30)	NR	Multivariable	1.93 (1.03–3.62)	0.041
Kazanjan et al[83]	2008	182	112 (62)	20	Multivariable	2.66 (1.74-4.06)	< 0.001

OS: Overall survival; PNI: Perineural invasion.