Rectal washout in rectal cancer surgery
Author
Summary, in English
Background
Rectal washout (RW) is performed to eliminate intraluminal cancer cells and thereby reducing the risk of local recurrence (LR). The overall aim of this thesis was to investigate the importance of RW in rectal cancer surgery.
Method
Paper I: Survey of the current practice of RW among Swedish colorectal units.
Paper II: The association between RW and 30-day postoperative complications after anterior resection (AR) for rectal cancer was analysed using data from the Swedish Colorectal Cancer Registry (SCRCR).
Paper III: The impact of RW on the 5-year oncological outcome after abdominoperineal resection (APR) for rectal cancer was analysed using data from the SCRCR.
Paper IV: The impact of RW on the 3- and 5-year oncological outcome after AR for rectal cancer was analysed using data from the SCRCR.
Paper V: Patients undergoing transanal total mesorectal excision (taTME) for rectal cancer were assessed for the presence of intraluminal cancer cells during RW.
Results
Paper I: RW was reported to be routinely performed in open and minimally invasive rectal cancer surgery, most often using sterile water or an alcohol-based solution with a minimum volume of 100-Paper II: The RW group had fewer overall and surgical complications. RW was not a risk factor for overall complications (odds ratio (OR) 0.73, 95% confidence interval (CI) 0.60-0.90, p=0.002) or for surgical complications (OR 0.62, 95% CI 0.50-0.78, pPaper III: There were no differences between the RW and no RW group in rates of LR (10/265 (3.8%) vs. 87/2160 (4.0%), p=0.839), distant metastasis (51/265 (19.2%) vs. 476/2160 (22.0%), p=0.293) and overall recurrence (53/265 (20.0%) vs. 505/2160 (23.4%), p=0.213) at 5-year follow up.
Paper IV: RW in AR did not impact the 3-year oncological outcome. A decreased 5-year risk of LR was observed after RW in multivariable analysis (hazard ratio 0.53, 95% CI 0.31-0.90, p=0.018).
Paper V: Only three of 21 patients had washout samples positive for cancer cells and all samples were negative after 500 ml of RW.
Conclusion
This thesis contributes to increased knowledge about RW and investigates the importance of RW in rectal cancer surgery. Swedish practice of RW is described. RW in AR for rectal cancer seems to be a safe technique with no evidence of increased 30-day postoperative complications. Routine RW in APR for rectal cancer to improve the 5- year oncological outcome is not supported. RW in AR for rectal cancer does not appear to impact the 3-year oncological outcome. However, RW was associated with decreased 5-year risk of LR, justifying continued practice of RW in AR for rectal cancer. Even if intraluminal cancer cells were rare during RW in taTME for rectal cancer, 500 ml of RW is probably needed to ensure elimination of intraluminal cancer cells.
Rectal washout (RW) is performed to eliminate intraluminal cancer cells and thereby reducing the risk of local recurrence (LR). The overall aim of this thesis was to investigate the importance of RW in rectal cancer surgery.
Method
Paper I: Survey of the current practice of RW among Swedish colorectal units.
Paper II: The association between RW and 30-day postoperative complications after anterior resection (AR) for rectal cancer was analysed using data from the Swedish Colorectal Cancer Registry (SCRCR).
Paper III: The impact of RW on the 5-year oncological outcome after abdominoperineal resection (APR) for rectal cancer was analysed using data from the SCRCR.
Paper IV: The impact of RW on the 3- and 5-year oncological outcome after AR for rectal cancer was analysed using data from the SCRCR.
Paper V: Patients undergoing transanal total mesorectal excision (taTME) for rectal cancer were assessed for the presence of intraluminal cancer cells during RW.
Results
Paper I: RW was reported to be routinely performed in open and minimally invasive rectal cancer surgery, most often using sterile water or an alcohol-based solution with a minimum volume of 100-Paper II: The RW group had fewer overall and surgical complications. RW was not a risk factor for overall complications (odds ratio (OR) 0.73, 95% confidence interval (CI) 0.60-0.90, p=0.002) or for surgical complications (OR 0.62, 95% CI 0.50-0.78, pPaper III: There were no differences between the RW and no RW group in rates of LR (10/265 (3.8%) vs. 87/2160 (4.0%), p=0.839), distant metastasis (51/265 (19.2%) vs. 476/2160 (22.0%), p=0.293) and overall recurrence (53/265 (20.0%) vs. 505/2160 (23.4%), p=0.213) at 5-year follow up.
Paper IV: RW in AR did not impact the 3-year oncological outcome. A decreased 5-year risk of LR was observed after RW in multivariable analysis (hazard ratio 0.53, 95% CI 0.31-0.90, p=0.018).
Paper V: Only three of 21 patients had washout samples positive for cancer cells and all samples were negative after 500 ml of RW.
Conclusion
This thesis contributes to increased knowledge about RW and investigates the importance of RW in rectal cancer surgery. Swedish practice of RW is described. RW in AR for rectal cancer seems to be a safe technique with no evidence of increased 30-day postoperative complications. Routine RW in APR for rectal cancer to improve the 5- year oncological outcome is not supported. RW in AR for rectal cancer does not appear to impact the 3-year oncological outcome. However, RW was associated with decreased 5-year risk of LR, justifying continued practice of RW in AR for rectal cancer. Even if intraluminal cancer cells were rare during RW in taTME for rectal cancer, 500 ml of RW is probably needed to ensure elimination of intraluminal cancer cells.
Department/s
Publishing year
2023
Language
English
Publication/Series
Lund University, Faculty of Medicine Doctoral Dissertation Series
Issue
2023:64
Full text
Document type
Dissertation
Publisher
Lund University, Faculty of Medicine
Topic
- Surgery
Keywords
- Rectal washout
- Rectal cancer surgery
- Local recurrence
- Anterior resection
- abdominoperineal resection
- Transanal total mesorectal excision
Status
Published
Project
- Rectal washout in rectal cancer surgery
Research group
- Surgery
Supervisor
ISBN/ISSN/Other
- ISSN: 1652-8220
- ISBN: 978-91-8021-404-9
Defence date
2 June 2023
Defence time
09:00
Defence place
Cronbergssalen, plan 6, Ruth Lundskogs gata 3, Skånes Universitetssjukhus i Malmö
Opponent
- Joakim Folkesson (Associate Professor of Surgery)