Short-term clinical outcomes of laparoscopic vs open rectal excision for rectal cancer: A systematic review and meta-analysis

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)

¹Hand-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.

Table 2 Results of the meta-analyses comparing laparoscopic rectal resection vs open rectal resection

Outcome variables	Number of studies (Number of patients)	RR or MD	95%CI(Low; High)	P value	Heterogeneity, I2(P value)	Sensitivity analysis by including the largest multi-centric RCTs
						Number of studies (Number of patients)	RR or MD	95%CI (Low; High)	P value	Heterogeneity, I2 (P value)
Intraoperative outcomes
Operative time	12 (3723)	36.67	27.22; 46.11	<0.00001	89% (< 0.00001)	4 (2319)	41.18	24.88; 57.48	< 0.00001	85% (0.0002)
Intraoperative morbidity	4 (1909)	0.97	0.74; 1.27	0.82	8% (0.35)	2 (1500)	1.02	0.60; 1.72	0.94	61% (0.11)
Estimated blood loss	11 (3380)	-88.8	-117.25; -60.34	< 0.00001	83% (< 0.00001)	4 (2319)	-82.1	-158.87; -5.34	0.04	94% (< 0.00001)
Incision length	5 (1629)	-11.17	-13.88; -8.47	< 0.00001	99% (< 0.00001)	3 (1275)	-10.51	-16.16; -4.85	0.0003	99% (< 0.00001)
Ureter injury	5 (2256)	1.23	0.20; 7.72	0.82	51% (0.11)	2 (1500)	2.59	0.66; 10.11	0.17	0% (0.67)
Gastrointestinal injury	4 (2052)	1.14	0.25; 5.17	0.86	73% (0.02)	2 (1500)	1.05	0.13; 8.22	0.96	86% (0.007)
Postoperative outcomes
Postoperative morbidity	12 (3313)	0.98	0.88; 1.09	0.75	16% (0.3)	3 (1844)	1.02	0.91; 1.15	0.69	0% (0.65)
Postoperative mortality	13 (3751)	0.65	0.34; 1.23	0.19	0% (1)	4 (2319)	0.60	0.27; 1.33	0.21	0% (0.89)
Length hospital stay	12 (3738)	-1.71	-2.84; -0.58	0.003	90% (< 0.00001)	4 (2296)	-0.25	-0.90; 0.39	0.44	52% (0.10)
Anastomotic leak	9 (2253)	0.97	0.69; 1.34	0.84	0% (0.6)	3 (1351)	1.19	0.79; 1.80	0.41	0% (0.53)
Reoperation rate	7 (2468)	0.93	0.64; 1.34	0.69	3% (0.4)	3 (1844)	1.19	0.77; 1.86	0.43	0% (0.42)
Ileus	10 (2930)	0.77	0.55; 1.06	0.11	0% (0.66)	3 (1875)	0.79	0.43; 1.44	0.44	62% (0.07)
Bowel recovery	9 (3149)	-0.68	-1.00; -0.36	< 0.0001	79% (< 0.00001)	3 (1922)	-0.59	-1.24; 0.07	0.08	87% (0.0005)
Wound infection	10 (2684)	0.81	0.61; 1.09	0.16	0% (0.5)	1 (1042)	0.82	0.43;1.47	0.5	NA
Chest infection	7 (1252)	1.55	0.82; 2.93	0.17	0% (0.61)	0 (0)	-	-	-	-
Urinary infection	7 (1075)	0.89	0.50; 1.57	0.68	15% (0.32)	0 (0)	-	-	-	-

RR: Risk ratios; MD: Mean difference; CI: Confidence interval; NA: Not applicable.