Clinical importance and surgical decision-making regarding proximal resection margin for gastric cancer

Table 1 Effects of positive margins on survival

Ref.	Inclusion	n	Effect of positive margins on survival
			All patientsP value	Subgroup analysis
				Nodal status	P value
Kim et al[11]	GC	619	< 0.0001	≤ 5 LNI	0.0001
				> 5 LNI	NS
Cascinu et al[19]	AGC	259	Significant	Node negative	0.001
				Node positive	NS
Cho et al[16]	AGC	2740	0.0028	Node negative	0.0001
				Node positive	0.259
Sun et al[16]	GC	2728	< 0.001	N0	< 0.001
				N1	0.007
				N3, N4	NS
Morgagni et al[17]	GC	89	< 0.0001	N0	0.001
				N1	0.003
				N2	0.009
				N4	NS

GC: Gastric cancer; AGC: Advanced gastric cancer; NS: Not significant; LNI: Lymph node involvement.

Table 2 Studies on an adequate length of proximal resection margin in gastric cancer

Ref.	Characteristics	RLPRM	Brief results of the study
Bozzetti et al[4]	without SI	≥ 3 cm	No positive margin if gross PRM ≥ 3 cm
	with SI	≥ 6 cm	No positive margin if gross PRM ≥ 6 cm
			(0% if PRM ≥ 6 cm vs 7% if PRM < 6 cm)
Ito et al[7]	Cardia
	T1, T2	≥ 4 cm	No positive margin if gross PRM ≥ 4 cm
	T3, T4	≥ 6 cm	No positive margin if gross PRM ≥ 6 cm
Papachristou et al[3]	Gastric cancer	≥ 6.5 cm	Median length of gross PRM in patients with or without recurrences: 6.5 cm vs 3.5 cm, respectively
Kim et al[36]	Upper third	≥ 2 cm	Recurrences: 8.2% (PRM > 2 cm) vs 14.5% (1-2 cm) and 30% (< 1 cm), P = 0.024
Ha et al[6]	EGC	-	PRM did not affect survival if margins were negative
	AGC	≥ 3 cm	Recurrences: 32.9% (PRM ≥ 3 cm) vs 37.6% (< 3 cm), NS; 5-yr survival: 57%(PRM ≥ 3 cm) vs 46% (< 3 cm), P = 0.02

RLPRM: Recommended length of proximal resection margin; PRM: Proximal resection margin; SI: Serosa infiltration; NS: Not significant; EGC: Early gastric cancer; AGC: Advanced gastric cancer.