Inclusion Criteria:

• 1. Adult patients (18 years of age or older)
• 2. Eligible to undergo open or minimally invasive sphincter-sparing low anterior resection with planned diverting loop ileostomy for malignancy, based on multidisciplinary team recommendations.
• 3. Eastern Cooperative Oncology Group (ECOG) Performance Status ≤ 2
• 4. Willingness to comply with protocol-specific treatment and study visits and to sign a written Informed Consent Form

Exclusion Criteria:

• Preoperative
• 1. History of left colitis
• 2. Known allergy to nickel or other components of the Colovac System (not applicable for control cohort)
• 3. Pregnant or nursing female subject
• 4. Concomitant major surgical procedure in combination with Colorectal resection (i.e., hepatectomy)
• 5. Any serious or uncontrolled medical disorder that, in the opinion of the investigator, may increase the risk associated with study participation, impair the ability of the participant to undergo protocol described procedures or interfere with the interpretation of study results including, but not limited to:
• 1. Stage IV colorectal cancer unless curative intent R0 resection is planned AND there is no associated peritoneal disease
• 2. Immunodeficiency (CD4+ count \< 500 CU MM)
• 3. Systemic steroid therapy within the past 6 months
• 4. Systemic infection at the time of surgery or requiring systemic antimicrobial therapy up to 1 week before surgery
• 5. Major surgical or interventional procedures within 30 days prior to this study or planned surgical or interventional procedures within 30 days of entry into this study
• 6. Diagnosis of bowel obstruction, bowel strangulation, peritonitis, bowel perforation, intraabdominal infection, ischemic bowel, or carcinomatosis
• 7. Fecal incontinence, involvement of sphincter by the neoplastic disease or evidence of extensive local disease in the pelvis seen on pre-operative imaging
• 8. Severe malnutrition defined as 10% weight loss within 3 months prior to enrollment.
• 6. The subject is currently participating in another investigational drug or device study
• Intraoperatively:
• 7. Occurrence of any of the following during the colorectal surgery:
• 1. Blood loss (\>750 cc)
• 2. Blood transfusion
• 3. Any new sign of bowel ischemia
• 4. Positive air leak test
• 5. Inadequate bowel preparation
• 6. Anastomosis location greater than 10 cm from the anal verge
• 7. Any other surgical complications or intra-operative risks that may place the patient at greater risk from study procedures