Prognostic effect of excessive chemotherapy cycles for stage II and III gastric cancer patients after D2 + gastrectomy

Table 4 Patient characteristics before and after propensity score matching based on the number of chemotherapy cycles for stage III gastric cancer

Variables	Before PSM		P value	After PSM		P value
	< 9 cycles, n = 278	≥ 9 cycles, n = 624		< 9 cycles, n = 242	≥ 9 cycles, n = 242
Sex			0.082			0.298
Male	207	497		185	175
Female	71	127		57	67
Age in yr	56.97 ± 9.85	59.91 ± 10.03	< 0.001	57.35 ± 9.31	58.01 ± 9.17	0.418
Depth of tumor invasion			0.568			0.754
T2	1	1		0	0
T3	72	152		60	63
T4	205	471		182	179
Number of positive lymph nodes			0.110			0.756
0	0	4		0	0
1-2	39	111		36	34
3-6	68	155		60	67
≥ 7	171	354		146	141
Type of gastrectomy			0.044			0.903
Proximal	16	36		13	12
Distal	89	154		71	71
Total	173	454		158	159
Vascular invasion			0.852			0.916
Negative	67	154		59	60
Positive	211	470		183	182
Neural invasion			0.156			0.288
Negative	85	211		74	85
Positive	193	403		168	157
Lauren classification			0.664			0.597
Intestinal	52	125		46	42
Diffuse	153	315		127	127
Mixed	73	184		69	73
Maximum diameter of tumor in cm			0.346			0.467
< 6	134	322		119	111
≥ 6	144	302		123	131
Surgical margin			0.571			0.254
Negative	260	577		225	218
Positive	18	47		17	24

PSM: Propensity score matching.