Conformal Sphincter-Preservation Operation Versus InterSphincteric Resection on Anal Function in Low Rectal Cancer

Naval Military Medical University

Status: Not yet enrolling

Conditions: Rectum Cancer

Treatments: Procedure: ISR; Procedure: CSPO

Study type: Interventional

Funder types: Other

Identifiers

NCT06567756

CSVIS

Details and patient eligibility

About

In this clinical trial, the investigators compared anal function, genitourinary function, quality of life, perioperative safety, and oncological prognosis after CSPO for patients with low rectal cancer, using ISR as a control, to provide high-level evidence-based medical evidence for the choice of anorectal preservation surgical approaches for patients with low rectal cancer.

Full description

The CSPO surgical approach is a series of targeted improvements designed primarily on the basis of analyzing the causes of poor postoperative function of the ISR, while building on research on the ultrastructure of the pelvic floor anal canal. For these reasons, the investigators designed the present study to compare anal function, quality of life, perioperative safety, and oncologic prognosis after CSPO for patients with low rectal cancer, using ISR surgery as a control, and to provide high-level evidence-based medical evidence for the choice of anorectal preservation surgical modalities for patients with low rectal cancer.

Enrollment: 84 estimated patients

Sex: All

Ages: 18 to 75 years old

Volunteers: No Healthy Volunteers

Inclusion criteria

1. Age: 18-75 years;
2. Pathologically confirmed: moderately & well-differentiated rectal cancer;
3. Low rectal cancer: lower edge of tumor ≦5cm from anal verge or ≦2cm from dentate line;
4. Tumor diameter: ≤3cm or <1/3 bowel circumference;
5. Tumor infiltration depth: cT1-2, Bordeaux/Rullier classification: type II-III;
6. Locally progressive rectal cancer (cT1-4N0-2M0): significant tumor downstaging and downgrading after preoperative neoadjuvant therapy, meeting the above criteria;
7. ASA score: I-III and ECOG score: 0-1;
8. Undergo elective TME for colorectal or colorectal-anal canal anastomosis;
9. Normal preoperative anal function: Wexner score <10, LARS score <20;
10. Agree to participate in the clinical trial and sign an informed consent form.

Exclusion criteria

1. Combination of synchronous or metachronous (within 5 years) malignant tumors;
2. Combined distant metastasis of the tumor;
3. Combined intestinal obstruction, intestinal perforation, or intestinal bleeding requiring emergency surgery;
4. Combined psychiatric disorders that do not allow them to understand and participate in the study;
5. Combined systemic diseases that cannot tolerate surgery;
6. Women who are pregnant or breastfeeding;
7. Other reasons, judged by the investigator, for not being suitable for participation in this clinical trial.

Trial design

Primary purpose: Treatment

Allocation: Randomized

Interventional model: Parallel Assignment

Masking: None (Open label)

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84 participants in 2 patient groups

Group A (experimental group): CSPO group

Experimental group

Description:

The distal rectum is isolated to the entrance of the internal and external sphincter space, and then an oblique resection line is designed under direct vision according to the tumor site and shape, ensuring that the distal and lateral margins are not less than 1 cm, and preserving the contralateral dentate line and intestinal wall as much as possible, and completing the anastomosis manually or with instruments.

Treatment:

Procedure: CSPO

Group B (control group): ISR group

Active Comparator group

Description:

Partial, subtotal, or complete resection of the internal sphincter and/or a portion of the longitudinal rectal muscle, expansion of the distal rectal incision margin into the anal canal or to the anal verge, and completion of colorectal-anal anastomosis manually or instrumentally

Treatment:

Procedure: ISR