Table 1.
Summary of the included randomized clinical trials
| Ref. | Number of centers involved (country) in the RCT and in the study period | Inclusion criteria | Exclusion criteria | n |
Surgical approach |
Types of procedure |
Preoperative treatment | ||||
| Lap (n) | Conversion rate (%) | Open (n) | Lap (%) | Open (%) | Lap (%) | Open (%) | |||||
| Fleshman et al[5], 2015 | 35 (United States-Canada) Oct 2008-Sep 2013 | S. II-III rectal cancer ≤ 12 cm from AV | 1-11 | 462 | 240 | 11.25 | 222 | LAR (74.6) APR (24.2) H (0.4) TPC (0.8) | AR (76.1) APR (21.2) TPC 6 (2.7) | CRT (95) RT (3.3) CT (1.7) | CRT (91.2) RT (5.5) CT (3.4) |
| Stevenson et al[6], 2015 | 24 (Australia-N. Zeal) Mar 2010-Nov 2014 | T1-3 rectal cancer ≤ 15 cm from AV | 1, 2, 4, 7, 10, 12, 13 | 473 | 238 | 8.82 | 235 | LAR (89) APR (11) | AR (90) APR (10) | RT (50) | RT (49) |
| Ng et al[20], 2014 | 1 (Hong Kong) Aug 2001-Aug2007 | Rectal cancer low margin 5-12 cm AV | 13, 16, 17, 23, 24, 25 | 80 | 40 | 7.5 | 40 | LAR (100) | AR (100) | 0 | 0 |
| van der Pas et al[3], 2013 | 30 (Europe- Canada-South Korea) Jan 2004-May 2010 | T1-3 rectal cancer ≤ 15 cm from AV | 1, 2, 9, 10, 13-22 | 1044 | 699 | 16.4 | 345 | LAR (70) APR (29) U (1) | AR (77) APR (23) | RT (59) CT (32) | RT (58) CT (34) |
| Liang et al[24], 2011 | 1 (China) May 2004-April 2008 | Rectal cancer | 16, 25, 26, 31, 34, 35 | 343 | 169 | 0.59 | 174 | LAR (50.9) APR (49.1) | AR (59.8) APR (40.2) | 0 | 0 |
| Kang et al[4], 2010 | 3 (South Korea) Apr 2006-Aug 2009 | T1-3 rectal cancer ≤ 9 cm from AV | 1, 5, 10, 13, 16, 21, 23, 26 | 340 | 170 | 1.18 | 170 | LAR (85.9) APR (14.1) | AR (88.8) APR (11.2) | CRT (100) | CRT (100) |
| Liu et al[18], 2010 | 1 (China) Feb 2005-Oct 2008 | Rectal cancer | 16, 17, 23 | 186 | 98 | 0 | 88 | 1LAR (69.4) H 14 (14.3) APR (12.2) O 4 (4.1) | AR (67) H (12.5) APR (15.9) O 4 (4.5) | 0 | 0 |
| Ng et al[21], 2009 | 1 (Hong Kong) Sep 1993-Oct 2002 | Rectal cancer low margin 12-15 cm AV | 1, 16, 23, 24, 27, 28 | 153 | 76 | 30.26 | 77 | LAR (100) | AR (100) | 0 | 0 |
| Luján et al[19], 2009 | 1 (Spain) Jan 2002-Feb 2007 | Mid or low rectal cancer | 1, 13, 18, 29 | 204 | 101 | 7.92 | 103 | LAR 77 (76.2) APR 24 (23.8) | AR (78.6) APR (21.4) | CRT (72.3) | CRT (74.8) |
| Ng et al[22], 2008 | 1 (Hong Kong) Sep1994-Feb 2005 | Low rectal cancer | 13, 16, 23, 24, 30 | 99 | 51 | 9.8 | 48 | APR (100) | APR (100) | 0 | 0 |
| Braga et al[17], 2007 | 1 (Italy) Period n.a. | Rectal cancer | 1, 2, 10, 13, 31 | 168 | 83 | 7.23 | 85 | LAR (91.6) APR (8.4) | AR (87) APR (13) | CRT (16.9) | CRT (14.1) |
| Guillou et al[26], 2005 | 27 (United Kingdom) Jul 1996 - Jul 2002 | Colorectal cancer (excl. transverse) | 11, 16, 17, 21, 32, 33 | 381 | 253 | 33.88 | 128 | AR 167 (66) APR (25) S (3) LH (2) O (3) U (1) | AR (62) RC 1 (1) S 7 (5) APR (27) O 4 (3) U (2) | NA | NA |
| Zhou et al[23], 2004 | 1 (China) Jun 2001 - Sep 2002 | 1.5 cm above AV to peritoneal reflection | 1, 13, 29 | 171[24] | 82 | na | 89 | LAR (100) | AR (100) | 0 | 0 |
| Araujo et al[25], 2003 | 1 (Brazil) Sep 1997-Sep 2000 | Low rectal cancer not responding RCT | 1 | 28 | 13 | 0 | 15 | APR (100) | APR (100) | CRT (100) | CRT (100) |
Hand-assisted procedures. Exclusion criteria: (1) Tumors other than histologically confirmed adenocarcinoma; (2) Age > 18 years; (3) body mass index (BMI) > 34, (4) Eastern Cooperative Oncology Group (ECOG) performance score ≥ 3; (5) Not receiving neoadjuvant chemoradiotherapy/radiotherapy; (6) Operation not performed between 4-12 wk of the final radiation treatment; (7) History of invasive pelvic malignancy within 5 years; (8) psychiatric or addictive disorders that affected compliance with the protocol, (9) American Society of Anesthesiologists (ASA) classification IV or V, (10) Severe systemic disease, (11) Conditions that limited the success of the laparoscopic resection; (12) Life expectancy of at least 12 weeks; (13) T4 tumors/involved CRM pretreatment; (14) T1 tumor treated with local transanal excision; (15) History of other malignancy except basocellular carcinoma of the skin or in situ carcinoma of the cervix uteri, (16) Signs of acute intestinal obstruction, (17) Need for synchronous colorectal surgery; (18) Familial adenomatous polyposis coli/hereditary non-polyposis; (19) Colorectal cancer; (20) Active Crohn’s disease/ulcerative colitis; (21) Pregnancy; (22) T3 rectal cancer within 2 mm from the endopelvic fascia; (23) Tumor perforation; (24) Tumor larger than 6 cm; (25) Neoadjuvant chemoradiotherapy; (26) Distant metastasis, (27) Distal tumor that needed an anastomosis within 5 cm of the dentate line; (28) Previous abdominal operations near the region of the colorectal operation; (29) Emergency surgery; (30) recurrent disease; (31) ongoing infection/ plasma neutrophil level < 2 × 109/L; (32) Associated gastrointestinal disease that needed surgical intervention; (33) Malignant disease in the past 5 years; (34) BMI > 30 kg/m2 and (35) previous abdominal surgery. AV: Anal verge; Lap: Laparoscopy; LAR: Laparoscopic anterior resection; AR: Anterior resection; APR: Abdominoperineal amputation; TPC: Total Proctocolectomy; H: Hartmann; S: Sigmoidectomy; LH: Left Hemicolectomy; RC: Right colectomy; O: Other; U: Unknown; CRT: Chemoradiotherapy; RT: Radiotherapy; CT: Chemotherapy.