Optimizing Patient Selection for Surgery Using Pathologic Analysis Following Neoadjuvant Therapy in Locally Advanced Rectal Cancer (OPAL)

Centre Hospitalier Universitaire Saint Pierre

Status: Enrolling

Conditions: Locally Advanced Rectal Cancer (LARC)

Treatments: Procedure: Endoscopic resection; Behavioral: Short interval restaging; Procedure: Total mesorectal excision

Study type: Interventional

Funder types: Other

Identifiers

NCT06761287

OPAL202412

Details and patient eligibility

About

This interventional, non-randomized, prospective trial aims to evaluate the role of endoscopic resection following neoadjuvant treatment in patients with locally advanced rectal cancer.

Phase I focuses on assessing the feasibility, safety and efficacy of endoscopic resection of residual scar or superficial residual neoplastic tissue following neoadjuvant treatment.

Phase II explores the potential of this approach to guide patient selection for total mesorectal excision and to serve as a definitive treatment option for those with limited residual disease.

Enrollment: 20 estimated patients

Sex: All

Ages: 18+ years old

Volunteers: No Healthy Volunteers

Inclusion criteria

• Age > 18 years old
• Signed informed consent
• Patients diagnosed with locally advanced rectal cancer showing complete or near-complete clinical response after neoadjuvant therapy without evidence of invasive disease (>T2) or locoregional invasion on magnetic resonance imaging and without any signs of metastatic disease on a computerized tomography scan.
• Patients diagnosed with locally advanced rectal cancer showing incomplete response with presence of superficial residual lesions, without invasive features on endoscopic evaluation, without evidence of invasive disease (>T2) or locoregional invasion on magnetic resonance imaging and without any signs of metastatic disease on a computerized tomography scan.
• Without previous medical history of rectal cancer or rectal surgery

Exclusion criteria

• Previous medical history of rectal cancer
• Previous rectal surgery

Trial design

Primary purpose: Treatment

Allocation: Non-Randomized

Interventional model: Parallel Assignment

Masking: None (Open label)

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20 participants in 4 patient groups

Complete clinical response

Experimental group

Description:

Defined as the presence of residual clear scar seen on endoscopic examination, without evidence of invasive disease (\>T2) or locoregional invasion on magnetic resonance imaging and without any signs of metastatic disease on a computerized tomography scan.

Treatment:

Procedure: Endoscopic resection

Near complete clinical response

Experimental group

Description:

Defined as the presence of irregular mucosa or small mucosal nodules or superficial ulceration or persisting erythema of the scar seen on endoscopic examination, without evidence of invasive disease (\>T2) or locoregional invasion on magnetic resonance imaging and without any signs of metastatic disease on a computerized tomography scan.

Treatment:

Procedure: Total mesorectal excision

Behavioral: Short interval restaging

Procedure: Endoscopic resection

Incomplete response with presence of superficial residual tissue

Experimental group

Description:

Defined as the presence of superficial residual tissue without features of deep invasion seen on endoscopic examination, without evidence of invasive disease (\>T2) or locoregional invasion on magnetic resonance imaging and without any signs of metastatic disease on a computerized tomography scan.

Treatment:

Procedure: Total mesorectal excision

Behavioral: Short interval restaging

Procedure: Endoscopic resection

No significant response

Active Comparator group

Description:

Persistant local signs of malignancy

Treatment:

Procedure: Total mesorectal excision