Table 1.
Patient, disease and treatment characteristics for 148 patients in the study and 44 patients excluded due to unavailability of follow-up
| Variable | Follow-up available | Follow-up unavailable | Follow-up vs none |
|---|---|---|---|
| No. (%) | No. (%) | p value1 | |
| All patients | 148 (100) | 44 (100) | |
| Age (years) mean ± SD | 69.2 ± 11.4 | 75.7 ± 11.1 | 0.001 |
| Median (IQR) | 71 (62, 78) | 78.5 (70, 84.2) | |
| Male | 78 (52.7) | 27 (61.4) | 0.401 |
| Year of surgery | |||
| 2003 | 27 (18.2) | 6 (13.6) | 0.005 |
| 2004 | 39 (26.4) | 9 (20.5) | |
| 2005 | 28 (18.9) | 18 (40.9) | |
| 2006 | 27 (18.2) | 10 (22.7) | |
| 2007 | 27 (18.2) | 1 (2.3) | |
| Tumour site | |||
| Colon | 59 (39.9) | 17 (39.5) | 0.559 |
| Rectum | 55 (37.2) | 13 (30.2) | |
| Sigmoid/rectosigmoid | 34 (23) | 13 (30.2) | |
| Tumour type | |||
| Adenocarcinoma NOS | 132 (89.2) | 43 (97.7) | 0.125 |
| Mucinous adenocarcinoma | 15 (1.1) | 1 (2.3) | |
| Carcinoid | 1 (.7) | 0 | |
| Histological grade | |||
| Low/well differentiated | 52 (35.2) | 15 (34.1) | 1 |
| Moderate | 78 (52.7) | 24 (54.5) | |
| High/poorly differentiated | 16 (1.8) | 5 (11.4) | |
| T-stage | |||
| T0 (in situ) | 0 | 1 (2.3) | 0.5 |
| T1 | 13 (8.8) | 2 (4.5) | |
| T2 | 35 (23.8) | 11 (25) | |
| T3 | 86 (58.5) | 26 (59.1) | |
| T4 | 13 (8.8) | 4 (9.1) | |
| N-stage | |||
| N0 | 92 (62.6) | 28 (63.6) | 0.932 |
| N1 | 35 (23.8) | 11 (25) | |
| N2 | 20 (13.6) | 5 (11.4) | |
| M-stage M1 | 3 (2) | 0 | 1 |
| Vascular invasion | 39 (27.3) | 12 (27.3) | 1 |
| Perineural invasion | 40 (27.8) | 11 (25.6) | 0.929 |
| Positive margins | 15 (10.3) | 4 (9.1) | 1 |
| Nodes examined | |||
| Mean ± SD | 15.4 ± 7.4 | 14.3 ± 5.7 | 0.319 |
| Median (IQR) | 13 (11, 19) | 14 (12, 17) | |
| Post-operative chemotherapy and/or radiation | 46 (31.1) | 4 (9.1) | 0.003 |
1 T-test for continuous variables, Pearson’s χ2 test or Fisher’s exact test for categorical variables