Endorectal Brachytherapy for Rectal Cancer (ICUREC)

University Hospital of Bordeaux

Status and phase

Enrolling

Phase 2

Conditions

Locally Advanced Rectal Carcinoma

Treatments

Radiation: Endorectal brachytherapy

Study type

Interventional

Funder types

Other

Identifiers

NCT05591534

CHUBX 2021/38

Details and patient eligibility

About

The management of rectal cancers has changed over the past decades towards a multidisciplinary strategy, combining radiotherapy, chemotherapy, and surgery. Local recurrence rates, dropped to less than 6 % with pre-operative radiotherapy and the standardization of total mesorectal excision (TME), at the price of increased peri-operative morbidity and functional sequelae. Since neoadjuvant treatment achieves up to 30 % complete response, organ preservation has been increasingly debated for good responders. With the introduction of better-quality imaging for tumour visualization and treatment planning, a new targeted radiation treatment was introduced with high dose rate endorectal brachytherapy (HDRBT), developped by Dr Te Vuong's team in Montreal. This treatment allows for radiotherapy dose escalation to increase the complete response rate, and subsequently the rate of patients amenable to rectal preservation. This phase 2 trial study is proposed to assess the feasibility of HDR brachytherapy after standard chemoradiotherapy among patients selected for rectal preservation.

Full description

The standard treatment for locally advanced rectal cancer consists in chemoradiotherapy followed by radical surgery with total mesorectal excision (TME) and adjuvant chemotherapy depending on lymph node status. This radiosurgical strategy has reduced local recurrence rates to less than 5% in expert centers, but at the cost of 20-30% morbidity and functional sequelae. Chemoradiotherapy can sterilize 15% of tumors, and up to 30% when neoadjuvant chemotherapy is given, calling into question the usefulness of systematic radical surgery in good responders. Ongoing trials are looking at treatment intensification either by chemotherapy intensification or by dose escalation in radiotherapy, with the aim of increasing the rectal preservation rate. Endorectal brachytherapy, developed by Prof. Té Vuong in Montreal, makes it possible to deliver a complementary dose directly to the tumor using a high-activity Iridium-192 radioactive source. It is an ambulatory treatment, which allows to deliver a complementary dose of 30 Gy in 3 sessions of 10 Gy at one week interval after external radiotherapy.

The objective of our trial is to demonstrate the feasibility of rectal brachytherapy for our patients in France with an acceptable toxicity rate similar to that described by the Canadian teams. In addition, this bicentric trial will allow to prove capacity to train radiotherapist colleagues in the technique of endorectal brachytherapy, which is an essential prerequisite for the development of the technique throughout France.

Main objective : To assess the feasibility of endorectal brachytherapy in patients showing partial response after standard neoadjuvant therapy with a goal of rectal preservation.

Secondary objectives: To describe the potential efficacy of endorectal brachytherapy in patients with partial response after standard neoadjuvant therapy by the complete clinical response rate and complete radiological response rate on MRI at 8 weeks, 4 months, 8 months, and 1 year, local recurrence rate, recurrence-free survival, and overall survival at 1 year Describe the rate of curative surgery (R0) in case of recurrence as well as the surgical morbidity according to the Dindo-Clavien score at 3 months after surgery.

Enrollment

31 estimated patients

Sex

All

Ages

18+ years old

Volunteers

No Healthy Volunteers

Inclusion criteria

Histologically proven rectal adenocarcinoma
Tumor cT2T3Tumor N0 or N1, M0
Size < 6cm and < 50% of circumference at initial workup, location ≤ 10 cm from anal margin
Partial response assessed on MRI 3-8 weeks after completion of external beam radiation therapy
Resolved rectal toxicity from external radiotherapy (grade ≤ 1) at the time of inclusion
ECOG performance index ≤ 2
Patient ≥ 18 years of age
Patient likely to receive radiation therapy
Effective contraception for patients of childbearing potential: male patients and women of childbearing potential must agree to use two medically validated methods of contraception (one for the patient and one for the partner) during treatment and at least until 6 months after the last treatment
Informing the patient and obtaining free, informed and written consent, signed by the patient and the investigator
Subject affiliated or beneficiary of a social security system of a member state of the European Community (article L1121-11 of the Public Health Code)

Exclusion criteria

T1 or T4 tumor
Tumor size > 6 cm or > 50% of circumference at initial workup
Invaded external sphincter or levator ani
N2 tumor (> 3 positive nodes)
Upper rectal tumor (> 10 cm from anal margin)
Metastatic disease
Contraindication to radiotherapy
Unusual and unresolved rectal toxicity from external radiation therapy (> grade 1) at the time of inclusion
Pregnant, potentially pregnant, or breastfeeding women
Persons deprived of liberty or under guardianship or unable to give consent
Inability to undergo medical monitoring of the trial for geographical, social or psychological reasons