Prophylactic lateral pelvic lymph node dissection in stage IV low rectal cancer

Table 3 Univariate and multivariate analyses of different prognostic factors for overall survival

Variable	Modality	n	Univariate		Multivariate
			5-yr OS (%)	P value	HR (95%CI)	P value
Age (yr)	< 65	32	27.9	0.095	1
	≥ 65	18	14.8		1.5 (0.8–3.0)	0.197
Sex	Male	43	19.8	0.618
	Female	7	42.9
Preoperative CEA level (ng/mL)	< 20	21	23.7	0.671
	≥ 20	29	22.9
Tumor size (mm)	< 60	15	29.6	0.634
	≥ 60	35	20.9
T category	T2, 3	25	17.3	0.515
	T4	25	32.5
Histopathological grading	G1, 2	36	25	0.348
	G3	14	21.4
Lymphatic invasion	Absence	6	0	0.446
	Presence	44	24.2
Venous invasion	Absence	10	40	0.215
	Presence	40	19.1
Lymph node metastasis	Absence	9	0	0.904
	Presence	41	27.5
LPLND	Absence	23	17	0.523
	Presence	27	28.7
No. of metastatic organs	1	44	23.8	0.866
	2	6	22.2
Metastatic organ	Liver only	25	36	0.241
	Others	25	10.6
Grade ≥ 3 complication of primary tumor resection	Absence	38	28.8	0.398
	Presence	12	9.5
Residual tumor status	R0	20	59	< 0.001	1
	R2	30	3.6		2.1 (1.4–3.0)	< 0.001
Preoperative chemotherapy	Absence	41	17.6	0.254
	Presence	9	55.6
Postoperative chemotherapy	Absence	7	38.1	0.397
	Presence	43	24.3

OS: Overall survival; CEA: Carcinoembryonic antigen; LPLND: Lateral pelvic lymph node dissection.