Does the Management of Anastomotic Leakage After Low Rectal Resection Affect Survival

Study Overview
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Brief Summary
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The aim of this retrospective cohort-study is to assess the effects of AL and its severity divided according the ISREC-classification on the long-term oncological outcome.

Detailed Description
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Rectal cancer is one of the most common malignancies in the world. Its costs and cancer-related mortality are increasing worldwide. The surgical treatment was revolutionized in recent years by the total mesorectal excision (TME) technique as well as the laparoscopic, robotic, and transanal approach. But anastomotic leakage (AL) remains one of the most feared complications after low rectal resection regarding postoperative morbidity and mortality as well as functional outcome. Several risk factors causing AL like low level of anastomosis, large tumor mass, male gender, smoking, perioperative bleeding, and preoperative radio-chemotherapy are known. Protective ileo- or colostomy formation and transanal tube placement may decrease the risk of AL and reduces the rate of reoperation due to AL. Diverting results of the association between AL and the long-term oncological outcome (local recurrence, systemic recurrence, survival) are described in the current literature. The International Study Group of Rectal Cancer (ISREC) provides a classification of AL according to its clinical management: Grade A results in no change in patient's management Grade B requires active therapeutic intervention without re-laparotomy Grade C requires re-laparotomy This classification allows a good stratification regarding postoperative morbidity and mortality. However, the association between the ISREC-classification of AL and the long-term oncological outcome is not yet clear.

Official Title
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Does the Management of Anastomotic Leakage After Low Rectal Resection Affect the Long-term Oncological Outcome: A Retrospective Propensity Score Adjusted Cohort Study

Conditions
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Rectal Cancer, Anastomotic Leak

Intervention / Treatment
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* Other: Anastomotic leakage


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Patients receiving elective low anterior resection (LAR) between February 1991 and December 2020 at the Cantonal Hospital of St. Gallen Exclusion Criteria: Other diagnosis than rectal cancer Discontinuity resection (no anastomosis) Emergency situation R1-resection Incomplete staging Metastatic cancer 30-day mortality Decline of a retrospective data analysis Secondary malignancy Age under 18 years

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 |
| --- | --- |
| leak<br>Patients with diagnosed anastomotic leakage after low rectal resection for rectal cancer UICC stage I to III | Other: Anastomotic leakage<br>* Anastomotic leakage was defined as a defect of the intestinal wall at the anastomotic site leading to a communication between the intra- and extraluminal compartments. It was diagnosed by clinical, laboratory, radiological (ultrasound, endosonography, computed tomography), endoscopic, and/or surgical findings.<br>|
| noleak<br>Patients without anastomotic leakage after low rectal resection for rectal cancer UICC stage I to III | |

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Cancer-specific survival |  | 30 days postoperative to 5 years postoperative | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Overall survival |  | 30 days postoperative to 5 years postoperative | 
| Disease-free survival |  | 30 days postoperative to 5 years postoperative | 
| Recurrence-free survival |  | 30 days postoperative to 5 years postoperative | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Rectal cancer, Low rectal resection, Anastomotic leakage, ISREC-classification, Cancer-specific survival, Propensity score