Meta-analysis of transanal vs laparoscopic total mesorectal excision of low rectal cancer: Importance of appropriate patient selection

Table 1 Included studies related data

Ref.	Publication year	Journal	Country	Study design	TaTME	LaTME
de’Angelis et al[13]	2015	Langenbecks Arch Surg	France	Retrospective observational study	32	32
Kanso et al[14]	2015	Dis Colon Rectum	France	Retrospective observational study	51	34
Pontallier et al[15]	2016	Surg Endosc	France	RCT	38	34
Marks et al[16]	2016	Tech. Coloproctol	United States	Retrospective observational study	17	17
Lelong et al[17]	2017	J Am Coll Surg	France	Retrospective observational study	34	38
Denost et al[18]	2018	Surg Endosc	France	RCT	50	50
Mege et al[19]	2018	Colorectal Dis	France	Retrospective observational study	34	34
Rubinkiewicz et al[20]	2018	Cancer Manag Res	Poland	Retrospective observational study	35	35
Roodbeen et al[21]	2019	Surg Endosc	Netherlands	Retrospective observational study	41	41
Rubinkiewicz et al[22]	2019	BMC Surg	Poland	Prospective observational study	23	23
Ren et al[23]	2021	Asian J Surg	China	Prospective observational study	32	32
Li et al[24]	2022	Gastroenterol Res Pract	China	Prospective observational study	106	106

TaTME: Transanal total mesorectal excision, LaTME: Laparoscopic total mesorectal excision; RCT: Randomised controlled trial.

Table 2 Included studies related data

Ref.	Publication year	Age	Gender	BMI	Neoadjuvant therapy	Tumour stage	Tumour location	Distance of tumour to anal verge
de’Angelis[13]	2015	64.91 ± 10.05 vs 67.16 ± 9.61	66% vs 66%	25.19 ± 3.52 vs 24.53 ± 3.19	100% vs 100%	I: 65.6% vs 56.3%; II: 31.3% vs 40.6%; III: 3.1% vs 3.1%	Low rectum	4 (2.5-5.0) vs 3.7 (2.5-5.0)
Kanso et al[14]	2015	59 ± 11 (32-79) vs 59 ± 11 (33-82)	71% vs 77%	24 ± 4 (17-32) vs 24 ± 4 (15-34)	80% vs 79%	NR	Lower rectum	1.6 ± 0.8 (0-3.5) vs 1.8 ± 0.9 (0-3.5)
Pontallier et al[15]	2016	62 (39-81) vs 62 (35-82)	68% vs 62%	25.5 vs 24.8	79% vs 88%	I: 21% vs 21%; II: 19% vs 14%; III: 60% vs 65%	Low rectum	4 (2-6) vs 4 (2-6)
Marks et al[16]	2016	60 vs 59	NR	25.9 vs 26.4	NR	I: 29.4% vs 23.5%; II: 70.6% vs 76.5%	Low rectum	< 4 vs < 4
Lelong et al[17]	2017	NR	68% vs 58%	24 (18.6-45.0) vs 24.2(17.7-32.7)	88.2% vs 92.1%	I: 17.6% vs 23.7%; II: 70.6% vs 71.0%; III: 11.8% vs 5.3%	Low rectum	NR
Denost et al[18]	2018	64 (39-82) vs 63 (31-90)	74% vs 64%	25.1 (17.3-33.2) vs 25.6 (18.3-38.3)	78% vs 84%	NR	Low rectum	4 (2-6) vs 4 (2-6)
Mege et al[19]	2018	58 ± 14 vs 59 ± 13	68% vs 68%	25 ± 4 vs 25 ± 3	85% vs 85%	I: 29.4% vs 11.8%; II: 67.6% vs 82.3%; III: 43.5% vs 47.8%; IV: 2.9% vs 5.9%	Low rectum	NR
Rubinkiewicz et al[20]	2018	64.3 ± 10.1 vs 60.3 ± 10.2	69% vs 69%	26.10 ± 4.09 vs 27.10 ± 4.71	88.6% vs 88.6%	I: 42.9% vs 45.7%; II: 57.1% vs 54.3%	Low rectum	2.90 ± 1.17 vs 3.19 ± 1.47
Roodbeen et al[21]	2019	62.5 ± 10.7 vs 66.0 ± 9.2	82.9% vs 78%	26.7 ± 1.9 vs 26.1 ± 4.0	43.9% vs 43.9%	I: 22.0% vs 19.5%; II: 36.6% vs 39%; III: 31.7% vs 31.7%; IV: 9.8% vs 9.8%	Low rectum	2.0 (0.0-4.0) vs 1.5 (0.0-3.0)
Rubinkiewicz et al[22]	2019	60 (51-67) vs 64 (58-67)	69% vs 69%	26 (22.8-29.7) vs 26.5 (23.8-30.6)	78.2% vs 82.6%	NR	Low rectum	3(2-4) vs 4 (3-5)
Ren et al[23]	2021	65.78 ± 12.37 vs 67.16 ± 10.03	59.3% vs 56.2%	22.87 ± 2.66 vs 23.05 ± 2.70	71.8% vs 65.6%	I: 34.3% vs 37.5%; II: 28.1% vs 31.2%; III: 31.2% vs 21.8%	Low rectum	5.53 ± 0.98 vs 5.78 ± 0.94
Li et al[24]	2022	55 ± 12 (23-78) vs 56 ± 12 (26-79)	100% vs 100%	23:0 ± 2.9 vs 22:9 ± 3.2	100% vs 100%	NR	Low rectum	3.6 ± 0.9 (2.0-5.0) vs 3.8 ± 0.9 (1.4-5.0)

Transanal total mesorectal excision vs Laparoscopic total mesorectal excision. BMI: Body mass index; NR: Not reported.

Table 3 Methodological quality of the observational studies assessed with the Newcastle-Ottawa scale

Author	Representativeness of the exposed cohort	Selection of the non-exposed cohort	Ascertainment of exposure	Demonstration that outcome of interest was not present at start of study	Comparability of cohorts on the basis of the design or analysis	Assessment of outcome	Was follow-up long enough for outcomes to occur	Adequacy of follow up of cohorts	Total score
de’Angelis[13], 2015	*	*	*	*	**	*	*	*	9
Kanso et al[14], 2015	*	*	*	*	**	*	*	*	9
Marks et al[16], 2016	*	*	*	*	-	*	*	*	7
Lelong et al[17], 2017	*	*	*	*	*	*	*	*	8
Mege et al[19], 2018	*	*	*	*	**	*	*	*	9
Rubinkiewicz et al[20], 2018	*	*	*	*	**	*	*	*	9
Roodbeen et al[21], 2019	*	*	*	*	**	*	*	*	9
Rubinkiewicz et al[22], 2019	*	*	*	*	*	*	*	*	8
Ren et al[23], 2021	*	*	*	*	**	*	*	*	9
Li et al[24], 2022	*	*	*	*	**	*	*	*	9