Volume-outcome Relationship in Rectal Cancer Surgery

Study Overview
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Brief Summary
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Hospital centralization effect is reported to lower complications and mortality especially for high risk and complex general surgery operations, including colorectal surgery. However, no linear relation between volume and outcome has been demonstrated. Aim of the study was to evaluate the increased surgical volume effect on early outcomes of patient undergoing restorative anterior rectal resection (ARR).

Official Title
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Volume-outcome Relationship in Rectal Cancer Surgery

Conditions
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Rectal Cancer, Anastomotic Leak Rectum

Intervention / Treatment
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* Other: Rectal cancer case centralization


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: diagnosis of a cancer located in the rectum, defined according to the international definition by D'Souza et al., elective setting anterior rectal resection with primary anastomosis (with or without diverting loop ileostomy). Exclusion Criteria: age below age of 18, inflammatory bowel disease, acquired or congenital immunodeficiency, preoperative infection, pregnancy, ASA IV, presence of synchronous cancers, abdominoperineal resection (APR), failure to perform rectal resection and primary anastomosis, emergency setting.

Ages Eligible for Study
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Minimum Age: 18 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| A<br>patients undergoing ARR with primary anastomosis between November 2016 and December 2020 after centralization of rectal cancer cases | Other: Rectal cancer case centralization<br>* In November 2016, the decision to centralize rectal cancer patients to only one surgical unit was taken, with only two surgeons performing the procedures. Furthermore, a close collaboration with local Gastroenterology Units and General Practiotioners was started in order to increase colorectal cancer case referral to our unit. At the same time, we decided to promote the use of laparoscopy and to implement ERAS protocol in our colorectal surgery practice.<br>|
| B<br>patients undergoing ARR with primary anastomosis between January 2006 and October 2016 | |

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Anastomotic leak | rate of any postoperative leakage of colo-rectal anastomosis clinically, radiologically or endoscopically demonstrated | up to 30 days after discharge | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Postoperative complications | rate of any surgical site infection clinically demonstrated | up to 30 days after discharge | 
| Surgical site infection | Rate of any complication after rectal resection | up to 30 days after discharge | 
| Pneumonia | rate of radiologically demonstrated pneumonia | up to 30 days after discharge | 
| Ileus | rate of any ileus clinically demonstrated | up to 30 days after discharge | 
| Bleeding | Rate of any clinically radiologically or endoscopically demonstrated bleeding after rectal resection | up to 30 days after discharge | 
| Reoperation | Rate of any reoperation | up to 30 days after discharge | 
| Readmission | Rate of any unplanned readmission after discharge | up to 90 days after discharge | 
| 30-days-mortality | Rate of any mortality | up to 30 days after discharge | 
| 1-year stoma persistence | rate of stoma persistence | up to one year after surgery | 
| Length of hospital stay | number of days between primary rectal resection and discharge | up to 30 days after discharge | 
| Use of minimally invasive approach | rate of minimally invasive rectal ARR performed | up to 30 days after discharge | 
| Operative time | Mean operative time | up to 30 days after discharge | 
| Conversion to open surgery | rate of conversion form laparoscopy to one surgery | up to 30 days after discharge | 
| need of postoperative blood transfusion | rate of postoperative transfusion | up to 30 days after discharge |