Lymph node harvest in colon and rectal cancer: Current considerations

Table 1 Observed overall 5-year survival rates by stage for colonic and rectal cancer

Rectum		Colon
TN	SEER- observed 5 year overall survival %	TN	SEER- observed 5 year overall survival %
T1
N0	81.4	N0	78.7
N1	72.1	N1a	73.7
N2a	73.8	N1b	67.2
N2b	53.2	N2a	64.7
		N2b	51.8
T2
N0	75.7	N0	74.3
N1	72.1	N1a	73.7
N2a	58.2	N1b	67.2
N2b	41.7	N2a	64.7
		N2b	51.8
T3
N0	64.0	N0	66.7
N1a	55.4	N1a	58.2
N1b	49.7	N1b	51.7
N2a	42.5	N2a	42.8
N2b	32.0	N2b	30.4
T4a
N0	55.7	N0	60.6
N1a	53.2	N1a	52.2
N1b	43.9	N1b	42.1
N2a	44.3	N2a	32.5
N2b	24.5	N2b	17.5
T4b
N0	44.7	N0	45.7
N1	24.3	N1a	30.6
N2a	18.5	N1b	25.4
N2b	12.3	N2a	18.3
		N2b	12.9

Taken from American Joint Committee on Cancer cancer staging manual 2009, Gunderson et al[12,13]. Nodal involvement: N0 - no involvement; N1 - 1-3 positive lymph nodes (LNs); N1a - 1 positive LN; N1b - 2-3 positive LN; N1c - tumor deposit(s) in the subserosa, mesentery or non-peritonealized pericolic or perirectal tissues without regional nodal metastases; N2- 4 or more positive LN; N2a- 4-6 positive LN; N2b- seven or more positive LN. SEER: Surveillance, Epidemiology and End Results.