APR with TME in Rectal Cancer
APR with TME refers to Abdominoperineal Resection with Total Mesorectal Excision—a surgical procedure for rectal cancer where the tumor directly involves the anal sphincter or levator muscles, requiring en bloc resection of the rectosigmoid, rectum, anus, surrounding mesentery, mesorectum, and perianal soft tissue, necessitating permanent colostomy creation 1.
When APR with TME is Indicated
APR with TME should be performed when:
- The tumor directly involves the anal sphincter or levator muscles
- A margin-negative resection would result in loss of anal sphincter function and incontinence
- The tumor is located in the distal rectum where sphincter-sparing surgery is not feasible 1
Technical Considerations
The procedure involves:
- En bloc resection of rectosigmoid, rectum, and anus
- Complete mesorectal excision (TME) through sharp dissection to remove the mesorectum as a "tumor package" including associated vascular and lymphatic structures, fatty tissue, and mesorectal fascia
- Autonomic nerve sparing when oncologically safe
- Permanent colostomy creation 1
Extralevator APR Variant
An extralevator APR approach may offer benefits over conventional APR, including:
- Lower rates of intraoperative perforation
- Reduced circumferential resection margin (CRM) involvement
- Decreased local recurrence rates
However, evidence shows inconsistencies between studies 1.
Quality of Life Implications
Critical caveat: Patients undergoing APR report significantly worse outcomes compared to sphincter-sparing surgery:
- Worse body image at 1 year post-surgery
- Worse micturition symptoms
- Less sexual enjoyment 1
Despite these functional differences, overall quality of life between patients with or without permanent colostomy appears fairly comparable in long-term follow-up 1.
Oncologic Outcomes
Important consideration: Retrospective comparisons show patients undergoing APR versus low anterior resection (LAR) have:
- Worse local control
- Worse overall survival
A retrospective study of 3,633 patients with T3-4 rectal cancer from 5 large European trials suggests an association between the APR procedure itself and increased risks of recurrence and death, though whether this is attributable to the procedure alone, patient/tumor characteristics, or a combination remains unclear 1.
Role in Organ Preservation Strategies
In contemporary organ preservation protocols following chemoradiotherapy (CRT), TME (including APR when necessary) is reserved for patients with poor response to neoadjuvant treatment, while those achieving clinical complete response (cCR) or partial response (PR) may be candidates for nonoperative management or local excision 2.