Dealing with robot-assisted surgery for rectal cancer: Current status and perspectives

Table 1 Clinically relevant outcomes

Outcome	Open-LAR	Robotic-LAR	P value1
Intraoperative transfusions	0	0	-
Death	0	0	-
Postoperative transfusions patients n (%)	6 (5.7)	1 (2.0)	0.432
Surgical complications (30th postop day)
Units	12	1	0.051
Infectious	15 (14.3)	8 (16.3)	0.189
Non-infectious	11 (10.5)	10 (20.4)
Both	5 (4.5)	0
Overall	31 (29.5)	18 (36.7)	0.371
Reinterventions (30th postop day)	0	2 (4.1)	0.100
Length of hospital stay (d) mean ± SD (Median)	12.4 ± 3.2 (12.0)	8.4 ± 9.3 (7.0)	< 0.001
Post-operative Hb (g/dL) mean ± SD (Median)	10.6 ± 1.6 (10.8)	11.0 ± 1.4 (10.8)	0.124
Hb drop (g/dL) mean ± SD (Median)	3.0 ± 1.4 (2.9)	2.4 ± 1.6 (2.0)	0.015

¹Two-sample two-sided Wilcoxon test, unpaired t-test; ²or two-sided Fisher’s exact test as appropriate. Modify from Biffi et al[30].

Table 2 Comparison between MRC CLASICC and COREAN trial

Variable	MRC CLASICC	COREAN Trial
Number of participating Centers	27	3
Number of procedures per surgeon before Trial	20	75
Conversion rate, n (%)	82 (34)	2 (1.2)
CRM involvement	16%	2.9%

CRM: Circumferential resection margin.

Table 3 Perioperative outcomes of robotic total mesorectal excision for rectal cancer n (%)

Ref.	n	BMI (kg/m2)	OR time (min)	Conversion rate	Anastomotic leak rate
Hellan et al[16]	39	26 (16-44)	285 (180-540)	1 (2.6)	4 (12.1)
Baik et al[17]	56	23.4 (18-33)	178 (120-315)	0	1 (1.8)
Choi et al[18]	50	23.2 (19.4-29.2)1	304.8 (190-485)3	0	4 (8.3)
Baek et al[19]	64	26.8 (16.5-44)	270 (150-540)	9.4	4 (7.7)
Pigazzi et al[15] (multicentric study)	143	26.5 (16.5-44)2	297 (90-660)3	7 (4.9)	16 (10.5)
Baik et al[20]	370	23.3 ± 2.9 (13.8-32.7)2	363.3 ± 94.8 (138.0-702.0)2	3 (0.8)	28 (7.7)
IEO series[14]	102	28.2 (17.6-43)	330 (155-540)	2 (1.9)	5 (6.6)

Only sphincter-saving operations included for calculating leak rates, values expressed as median (range) except where specified,

¹mean (range);

²mean ± SD (range);

³mean (range).

Table 4 Clinical results of laparoscopic and robotic surgery for rectal cancer

Ref.	Conversions (%)		P value	Hospital stay (d)		P value	Complications (%)		P value
	ROB	LAP		ROB	LAP		ROB	LAP
Park et al[58]	0	0	1.000	9.9	9.4	0.500	29.3	23.2	0.400
Kang et al[33]	2	3	1.000	11.7	14.4	0.006	20	27	0.400
Kwak et al[59]	0	3.4	0.400	NA	NA		32	27	NS
Baek et al[50]	7.3	22	0.116	6.5	6.6	0.800	22	27	1.000
Bianchi et al[60]	0	4	NA	6.5	6	0.400	16	24	0.500
Baik et al[17]	0	10.5	0.013	5.7	7.6	0.001	10.7	19.3	0.025
Patriti et al[63]	0	19	< 0.05	11.9	9.6	> 0.05	30.6	18.9	> 0.05

ROB: Robotic resection; LAP: Laparoscopic resection; NA: Not available; NS: Not significant.

Table 5 Oncologic results of laparoscopic and robotic surgery for rectal cancer

Ref.	Harvested lymph nodes (n)		P value	Distal resection margin (cm)		P value	Positive CRM (%)		P value
	ROB	LAP		ROB	LAP		ROB	LAP
Park et al[58]	17.3	14.2	0.06	2.1	2.3	NS	4.9	3.7	0.5
Kang et al[33]	14.7	16.6	NS	2.7	2.6	0.09	3	2	NS
Kwak et al[59]	20	21	0.7	2.2	2.8	0.8	1.7	0	> 0.9
Baek et al[50]	13	16	0.07	3.6	3.8	0.6	2.4	4.9	1
Bianchi et al[60]	18	17	0.7	2.0	2.0	1	0	4	0.9
Baik et al[17]	18.4	18.7	0.8	4.0	3.6	0.4	7	8	0.7
Patriti et al[63]	10.3	11.2	> 0.05	2.1	435	> 0.05	0	0	NS

CRM: Circumferential resection margin; ROB: Robotic resection; LAP: Laparoscopic resection; NS: Not significant.

Table 6 Short-term and long-term oncologic outcomes of robotic TME for rectal cancer

Ref.	LN yield	CRM+ n (%)	DRM+ n (%)	FU (mo)	LR (%)	DR (%)	DFS (3 yr), (%)	OS (3 yr), (%)
Hellan et al[16]	13 (7-28)1	0	0	132	0	10.3	-	-
Baik et al[17]	17.5 (4-43)1	4 (7.1)	0	14.32	0	3.6	-	-
Choi et al[18]	20.6 (6-48)3	1 (2)	0	-			-	-
Baek et al[19]	14.5 (3-28)1	0	0	20.24	3.1	9.4	73.7	96.2
Pigazzi et al[15] (Multicenter study)	14.1 (1-39)3	1 (0.7)	1 (0.9)	17.44	1.5	9.0	77.6	97
Baik et al[20]	15.6 ± 9.0 (1-49)+	21 (5.7)		26.54	3.6	17.6	79.2	93.1
Ieo series, Ghezzi et al[14]	14.5 (2-45)3	5 (4.9)	2 (1.9)	30.02	4.0	10.7	79.2	92

¹mean ± SD (range);

²median followe-up;

³mean lymphnode yield;

⁴mean followup. LN: Lymph node; CRM+: Circumferential resection margin positivity; DRM+: Distal resection margin positivity; FU: Follow up; LR: Local recurrence; DR: Distant recurrence; DFS: Disease free survival; OS: Overall survival.

Table 7 Urinary and sexual dysfunctions results in robotic rectal resection

Ref.	Study	Results
Kim et al[13], 2012	39 LAP vs 30 ROB (urinary)	Earlier recovery of normal voiding and sexual function
	20 LAP vs 18 ROB (sexual male only)
D'Annibale et al[48], 2013	30 LAP vs 30 ROB (male only)	Erectile function was restored completely in the ROB group and partially in the LAP group
Luca et al[49], 2013	74 ROB (38 males and 36 females)	Sexual function and general sexual satisfaction were restored completely. Urinary function unchanged after surgery

LAP: Laparoscopic rectal surgery; ROB: Robotic rectal surgery.