A total number of 967 elderly patients were included in this study, with a median follow-up time of 42.1 months. Of the enrolled subjects, 662 patients (68.5%) received open surgery and 305 patients (31.5%) received laparoscopy surgery.
The demographic data were presented in Table 1. There was no difference in age and sex ratio between the open surgery group and the laparoscopy group. The laparoscopy group showed a higher rate of BMI increase (open vs. laparoscopy, overweight: 25.7% vs. 32.1%, obesity: 4.0% vs. 6.9%, p = 0.014) and comorbidities of hypertension (open vs. laparoscopy, 57.8% vs. 67.2%, p = 0.006). The presence of other comorbidities such as cardiac disease, cerebrovascular event, asthma, diabetes mellitus, and liver cirrhosis showed no difference between the two groups. The open group showed significantly advanced Tumor-Node-Metastasis (TNM) stage (stage 0, I, II and III in open vs. laparoscopy: 1.2%, 12.5%, 44.4%, 41.8% vs. 2.6%, 20.3%, 42.3%, 34.8%, p = 0.003), higher rate of abnormal preoperative serum CEA level (open vs. laparoscopy, 36% vs. 24%, p < 0.001) and higher rate of hypoalbuminemia (open vs. laparoscopy, 23.4% vs. 14.8%, p = 0.002). For other preoperative laboratory examinations, including preoperative anemia (Hb < 10 g/dL), abnormal AST or total bilirubin level, and elevated serum creatinine level (> 1.27 mg/dL) were all similar between the two groups.
Table 1
Characteristic | Open (n = 662) | Laparoscopy (n = 305) | P |
Age (y/o) | 80.4 ± 4.2 | 80.4 ± 4.6 | 0.878 |
Sex (male) | 369 (55.7) | 166 (54.4) | 0.703 |
Body mass index (kg/m2) | | | 0.014 |
Underweight (< 18.5) | 54 (8.3) | 16 (5.2) | |
Healthy (18.5–25) | 406 (62.1) | 170 (55.7) | |
Overweight (25–30) | 168 (25.7) | 98 (32.1) | |
Obese (> 30) | 26 (4.0) | 21 (6.9) | |
Hypertension | 384 (58.0) | 205 (67.2) | 0.006 |
Cardiac disease | 113 (17.1) | 60 (19.7) | 0.326 |
Cerebral vascular disease | 53 (8.0) | 20 (6.6) | 0.428 |
Asthma | 34 (5.1) | 14 (4.6) | 0.717 |
Diabetes Mellitus | 171 (25.8) | 74 (24.3) | 0.602 |
Cirrhosis | 11 (1.7) | 6 (2.0) | 0.737 |
TNM stage | | | 0.003 |
0 | 8 (1.2) | 8 (2.6) | |
1 | 83 (12.5) | 62 (20.3) | |
2 | 294 (44.4) | 129 (42.3) | |
3 | 277 (41.8) | 106 (34.8) | |
CEA > 5 (ng/ml) | 238 (36.0) | 75 (24.6) | < 0.001 |
Hb < 10 (g/dL) | 176 (26.6) | 76 (24.9) | 0.583 |
Albumin < 3.5 (g/dL) | 155 (23.4) | 45 (14.8) | 0.002 |
AST > 34 (U/L) | 50 (7.6) | 26 (8.5) | 0.602 |
Total bilirubin > 1.3 (mg/dL) | 16 (2.4) | 7 (2.3) | 0.908 |
Cr > 1.27 (mg/dL) | 141 (21.3) | 79 (25.9) | 0.113 |
Data are presented as n (%) unless otherwise indicated. CEA: carcinoembryonic antigen, Hb: hemoglobin, AST: aspartate transaminase, Cr: creatinine |
The operative data was shown in Table 2. Although the tumor locations were similar between the two groups, the rate of performing anterior resection was significantly higher in the laparoscopy group (open vs. laparoscopy, 56.6% vs. 60.7%, p = 0.048), and the rate of performing segmental resection, subtotal colectomy and Hartmann’s procedure were higher in the open surgery group. The open group and the laparoscopy group had similar retrieved lymph nodes (open vs. laparoscopy: 29.8 ± 14.9 vs. 30.3 ± 15.8, p = 0.636). The postoperative morbidity rate was 17.8% in the open group and 15.4% in the laparoscopy group (p = 0.354). The postoperative mortality rate was 1.7% in the open group and 0.3% in the laparoscopy group (p = 0.082). Although the postoperative morbidity and mortality were similar between both cohorts, the postoperative hospital stay was 10.3 ± 8.5 days in the laparoscopy group, which was significantly shorter than that in the open group of 13.5 ± 9.4 days (p < 0.001). There were 6 patients out of 305 patients (2.0%) received laparoscopy initially and then converted to open surgery. In Table 3, advanced pathology T stage was shown in the open cohort, but the N stage, histology type, and histology grade between the two cohorts were all similar.
Table 2
Characteristic | Open (n = 662) | Laparoscopy (n = 305) | P |
Tumor site | | | 0.419 |
Right colon | 196 (20.6) | 84 (27.5) | |
Left colon | 264 (39.9) | 115 (37.7) | |
Rectum | 202 (30.5) | 106 (34.8) | |
Operation types | | | 0.048 |
Right hemicolectomy | 174 (26.3) | 80 (26.2) | |
Left hemicolectomy | 41 (6.2) | 23 (7.5) | |
Anterior resection | 375 (56.6) | 185 (60.7) | |
Abdomino-peritoneal resection | 16 (2.4) | 8 (2.6) | |
Segmental resection | 13 (2.0) | 0 (0) | |
Subtotal colectomy | 17 (2.6) | 2 (0.7) | |
Hartmann’s procedure | 26 (3.9) | 7 (2.3) | |
No. of resected lymph nodes | 30.3 ± 15.8 | 29.8 ± 14.9 | 0.636 |
Duration of hospital stay after surgery (day) | 13.5 ± 9.4 | 10.3 ± 8.5 | < 0.001 |
Postoperative morbidity | 118 (17.8) | 47 (15.4) | 0.354 |
Postoperative mortality | 11 (1.7) | 1 (0.3) | 0.082 |
Conversion | | 6 (2.0) | |
Data are presented as n (%) unless otherwise indicated |
Table 3
Characteristic | Open (n = 662) | Laparoscopy (n = 305) | P |
T stage | | | 0.009 |
is | 8 (1.2) | 8 (2.6) | |
1 | 33 (5.0) | 27 (8.9) | |
2 | 78 (11.8) | 44 (14.4) | |
3 | 447 (67.5) | 198 (64.9) | |
4 | 96 (14.5) | 28 (9.2) | |
N stage | | | 0.108 |
0 | 385 (58.2) | 199 (65.2) | |
1 | 184 (27.8) | 69 (22.6) | |
2 | 93 (14.0) | 37 (12.1) | |
Histology | | | 0.886 |
Adenocarcinoma | 618 (93.4) | 287 (94.1) | |
Signet ring cell | 4 (0.6) | 1 (0.3) | |
Mucinous adenocarcinoma | 36 (5.4) | 16 (5.2) | |
Other | 4 (0.6) | 1 (0.3) | |
Histology grade | | | 0.123 |
Well | 67 (10.1) | 38 (12.5) | |
Moderate | 530 (80.1) | 248 (81.3) | |
Poor | 65 (9.8) | 19 (6.2) | |
Data are presented as n (%) unless otherwise indicated |
The median follow-up time was 47.9 months in the open group and 35.9 months in the laparoscopy group. The estimated 5-year-survival rate was 62% in the open group versus 66% in the laparoscopy group (Fig. 1, p = 0.224). The estimated 5-year cancer-specific survival rate was 81% in the open group versus 86% in the laparoscopy group (Fig. 1, p = 0.176). The estimated 5-year recurrence rate was 17% in the open group versus 16% in the laparoscopy group (Fig. 1, p = 0.314). The differences in OS, CSS, and CRR between the two groups were not statistically significant.
The 967 patients were divided into three groups by TNM stage: the stage 0 and I group, the stage II group, and the stage III group. We compared the OS, CSS, and CRR in the three groups after open surgery and laparoscopy surgery. In the stage 0 and I group, the OS, CSS and CRR were similar between the open group and the laparoscopy group (Fig. 2, open vs. laparoscopy, 5-year OS rate: 75% vs. 67%, p = 0.909, 5-year CSS rate: 97% vs. 94%, p = 0.875, 5-year CRR: 0% vs. 2%, p = 0.204). In the stage II group, the OS, CSS and CRR were similar between the open group and the laparoscopy group (Fig. 3, open vs. laparoscopy, 5-year OS rate: 66% vs. 72%, p = 0.575, 5-year CSS rate: 86% vs. 85%, p = 0.864, 5-year CRR: 15% vs. 14%, p = 0.220). In the stage III group, the OS, CSS and CRR were also similar between the open group and the laparoscopy group (Fig. 4, open vs. laparoscopy, 5-year OS rate: 51% vs. 60%, p = 0.575, 5-year CSS rate: 71% vs. 82%, p = 0.122, 5-year-CRR: 35% vs. 29%, p = 0.179).