ASA - A North American Multicenter Randomized Controlled Crossover Trial of Transanal Irrigation for Low Anterior Resection Syndrome

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A North American Multicenter Randomized Controlled Crossover Trial of Transanal Irrigation for Low Anterior Resection Syndrome
*Jessica Holland^², *Marie Demian^³, *Camila Oliveira^¹, *Li Tang^⁴, *Sahir Bhatnagar^⁵, *Alexander Sender Liberman^², *S�bastien Drolet^⁶, *Carl Brown^⁷, *Caitlin Cahill^⁸, *Sepehr Khorasani^⁷, *Terry Zwiep^⁹, *Carol-Ann Vasilevsky^², *Nancy Morin^², *Allison Pang^², *Richard Garfinkle^², *Sami A. Chadi^¹⁰, *Shafi Abdulkarim^², *Gordon Best^¹¹, *Julio Faria^², *Gabriela Ghitulescu^², *Husein Moloo^¹¹, *Louise Samuel^², Steven D. Wexner^¹², *Julio F. Fiore^², *Marylise Boutros^¹
^¹Digestive Disease & Surgery Institute, Cleveland Clinic, Weston, Florida; ^²Department of Surgery, McGill University, Montreal, Quebec; ^³Division of Colon and Rectal Surgery, Jewish General Hospital, McGill University, Montreal, Quebec; ^⁴Quantitative Health Sciences, Cleveland Clinic, Cleveland, Ohio; ^⁵Department of Epidemiology, Biostatics and Occupation Health, McGill University, Montreal, Quebec; ^⁶Department of Surgery, CHU de Quebec, Quebec City, Quebec; ^⁷Department of Surgery, St. Paul's Hospital, Vancouver, British Columbia; ^⁸Health Sciences North, Sudbury, Ontario; ^⁹Department of Surgery, London Health Sciences Centre, London, Ontario; ^¹⁰Toronto Western Hospital, Toronto, Ontario; ^¹¹Ottawa Hospital, Ottawa, Ontario; ^¹²Colorectal Surgery, Georgetown University, Washington, District of Columbia

Objective: The objective of this study was to evaluate the impact of transanal irrigation (TAI) compared with standard care on global quality of life (QoL) among North American rectal cancer patients with refractory low anterior resection syndrome (LARS).
Methods: This multicenter, assessor-blinded, crossover, pragmatic randomized controlled trial (RCT) (NCT05007015) was conducted at 8 Canadian sites. Adult patients with a LARS score >20 who had undergone low anterior resection for rectal cancer or advanced adenoma (gastrointestinal continuity restored without complication >6 months prior to enrollment for those with diverting ileostomy) were recruited. Participants were randomized in a 1:1 ratio to one of two sequences: (1) TAI followed by control (TAI-CON) or (2) CON followed by TAI (CON-TAI). Participants assigned to the TAI group received a Peristeen Plus Irrigation kit, virtual training, and access to a LARS-TAI mobile application. During the TAI phase, participants performed daily TAI for 3 months; during the CON phase, they continued their usual LARS care for 3 months. A one-month washout period separated the phases. Outcomes were assessed using patient-reported outcome measures. The primary outcome was global QoL, measured using the EORTC-QLQ-C30. Bowel function was assessed using the LARS score. Descriptive statistics were reported as mean (standard deviation) or counts (percentages), and all analyses were intention-to-treat. Continuous, ordinal, and binary outcomes were analyzed using linear, cumulative logit, and logistic mixed-effects models, respectively. Changes in LARS were assessed via chi-square tests with effect sizes and 95% confidence intervals (CI).
Results: Between 03/2022 and 12/2024, thirty-two adults (n=21 males, age: 63 ± 7 years) were randomized and completed follow up. Baseline demographics were comparable between groups. Significant treatment-by-time interactions were observed for LARS score (p=0.002), clustering of stools (p=0.012), and urgency (p=0.001) and approached significance for QoL (p=0.055). At the end of the intervention period, participants in the TAI arm had higher QoL (12.5; 95% CI: -23.9, -1.1; p=0.032) and lower LARS scores (-8.3; 95% CI: 3.1, 13.6; p=0.003) compared with those in the CON arm. Following TAI, participants had greater odds of improvement in stool clustering (OR = 6.6, 95% CI: 1.8-24.4) and urgency (OR = 16.8, 95% CI: 2.8-101.4) compared with CON. Among participants with major LARS at baseline, 47.8% improved during TAI compared with 9.1% during the CON period (p=0.004). The sequence of treatment did not affect any of the outcomes, indicating an absence of carryover or sequence bias.
Conclusion: This multicenter RCT - the largest to date and the first conducted in North America - demonstrated that TAI improves both QoL and LARS symptoms after restorative proctectomy. TAI represents an excellent management option that should be considered for wider adoption in rectal cancer survivorship care.
Table 1. LARS score and quality of life before and after TAI and CON interventions

	TAI (n=32)		CON (n=32)		Treatment x Time	Treatment Effect		Time Effect (3)
	Before	After	Before	After	Treatment x Time	Baseline (1)	Post intervention (2)	TAI	CON
LARS Score	33.63 ± 7.94	24.13 ± 12.75	33.34 ± 7.90	32.47 ± 7.51	0.002	0.886	0.003	<0.001	0.637
Quality of Life (4)	60.94 ± 26.30	77.08 ± 19.28	58.33 ± 23.95	64.58 ± 25.31	0.055	0.678	0.032	<0.001	0.086

Data are presented as mean ± standard deviation.
P values were detected with the use of linear mixed effects.
(1) Treatment effect at baseline (difference between TAI and CON before intervention).
(2) Treatment effect at post-treatment (difference between TAI and CON after intervention).
(3) Time effect represents within-treatment pre-to-post changes.
(4) A 10-point difference in quality of life scores is recommended as the minimally important difference for assessing the impact of quality of life interventions.
Abbreviations: CON: Control; LARS: Low anterior resection syndrome; TAI: Transanal irrigation.

Table 2. LARS categories before and after TAI and CON interventions

	TAI (n=32)		CON (n=32)
	Before	After	Before	After
LARS Categories
No LARS	2 (6.3)	12 (37.5)	1 (3.1)	3 (9.4)
Minor LARS	7 (21.9)	8 (25.0)	9 (28.1)	5 (15.6)
Major LARS	23 (71.9)	12 (37.5)	22 (68.8)	24 (75.0)

Data are presented as counts (percentages).
Abbreviations: CON: Control; LARS: Low anterior resection syndrome; TAI: Transanal irrigation.

Figure 1. Overview of the experimental protocol. Abbreviations: CON: Control; QoL: Quality of life; TAI: Transanal irrigation.

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