ProLARS Trial: Prospective Longitudinal Follow-up of Low Anterior Resection Syndrome (LARS) and COREFO Score After Rectum Surgery in Patients Undergoing Upfront Surgery or Different Neo-adjuvant Treatment Regimens

ProLARS Trial: Prospective Longitudinal Follow-up of Low Anterior Resection Syndrome (LARS) and COREFO Score After Rectum Surgery in Patients Undergoing Upfront Surgery or Different Neo-adjuvant Treatment Regimens

OBJECTIVE Low anterior resection syndrome (LARS) is a term for functional bowel complaints occurring after low anterior resection. Symptoms can range from faecal incontinence and frequent loose stools to urgency and incomplete emptying with great impact on quality of life. Little is known about the longitudinal evolution of LARS and the impact of different schedules of neoadjuvant chemoradiotherapy combined with surgery.

The investigators aim to investigate the incidence and evolution of functional bowel complaints in function of different neoadjuvant treatment regimens, type of surgery and adjuvant therapy in patients who undergo surgery for rectal cancer. The investigators focus on following objectives: evolution of LARS- and COREFO-scores per treatment regimen and their impact on work incapacity; identification of possible risk factors potentially related to functional outcome; monitoring and treatment of LARS.

METHODS This will be a multicentre prospective interventional study. The study population will consist of adult patients with rectal cancer, regardless of any neo-adjuvant therapy. Patients will be included for 5 years with a 2 year postoperative follow-up. Interim analysis will be made after 2 years of inclusion. Patients with intellectual disability or clinical colon obstruction are excluded. Automated online questionnaires including LARS and COREFO scores, incapacity for work and defecation quality will be sent at different time points (figure 1) using REDCap.

RESULTS and CONCLUSIONS Longitudinal change of LARS- and COREFO-scores will be visually summarized. Patient, disease or procedure specific risk factors will be assessed as well.

LARS is proven to be the principal postoperative problem after rectal surgery. If the investigators can predict the severity of LARS (minor or major LARS), this can be extremely helpful in deciding whether to perform a sphincter-sparing resection or a rectal amputation instead. Furthermore, the investigators want to offer perspective to patients who are susceptible to a disturbed postoperative bowel function.

Inclusion Criteria:

• 18 years or older.
• Diagnosis of rectal cancer, discussed at the multidisciplinary consultation, with the intention to perform a sphincter preserving total mesorectal excision (TME) or partial mesorectal excision (PME), regardless of the need of neoadjuvant treatment.

Exclusion Criteria:

• History of inflammatory bowel disease (Crohn's disease, ulcerative colitis) due to often persistent bowel complaints and therefore distorted baseline and follow-up data.
• Dementia or intellectual disability.
• Patients who are obstructive and in need a decompressive stoma or rectal stenting due to the lack of baseline data as they are often admitted to the hospital in an urgent setting