Abstract 3563
Background
The standard treatment for patients (pts) with localized squamous cell carcinoma of the anal canal (SCCAC) is chemoradiation (ChRT). Yet nearly 30% of patients are not cured and undergo salvage anorectal amputation. SCCAC is mostly a virus-associated tumor and thus potentially immunogenic. In fact, immune checkpoint inhibitors are promising in trials of metastatic SCCAC. Recently, studies have shown that the composition of the intestinal microbiota influences response to immunotherapy in some solid tumors, and the replacement of the intestinal "carcinogenic" by a protective microbiota has led to investigations with prebiotics and probiotics (PreProbiotics). Yet, there are no studies on the use of these agents in SCCAC. Thus we are conducting a randomized phase II study to test the efficacy of PreProbiotics during definitive ChRT aiming to improve the cure rate of pts with localized SCCAC.
Trial design
Randomized open label parallel phase II trial, where eligible pts will be randomized 1:1 to receive PreProbiotics starting one week prior to ChRT and throughout treatment until response evaluation at 6 to 8 weeks post ChRT or conventional ChRT. Eligible pts are ≥ 18 years, with histologically confirmed SCCAC, localized disease (≥ T2N0M0), indication to start definitive ChRT; HIV seropositive pts are eligible. Pts with active infection requiring antibiotics will be excluded. Primary endpoint: complete clinical and radiological response (CR) at 6 to 8 weeks post ChRT. Secondary endpoints: CR at 6 months, progression free survival, colostomy-free survival, metabolic response measured by 18-FDG PET-CT (baseline and at 6-8 weeks), toxicity, incidence of HPV in tumor tissues. All pts will have the following biological samples collected for correlative studies at baseline, 6-8 weeks and 6 months post ChRT: blood samples for circulating tumor DNA, inflammatory cytokines, anal/rectal swabs and feces to evaluate microbiota. Sample size assumptions: the H0 is CR at week 6 - 8 of 70% and H1, 90%; with a type I error of 10%, power of 80% and attrition rate of 10%, the final sample size is 75 patients.
Clinical trial identification
NCT03870607.
Editorial acknowledgement
Legal entity responsible for the study
Rachel Riechelmann.
Funding
AC Camargo Cancer Center.
Disclosure
All authors have declared no conflicts of interest.
Resources from the same session
1025 - Liver metastases (LM) from intrahepatic cholangiocarcinoma (iCCA): Outcomes from the European Network for the Study of Cholangiocarcinoma (ENS-CCA) registry and implications on current American Joint Committee on Cancer (AJCC) staging.
Presenter: Angela Lamarca
Session: Poster Display session 2
Resources:
Abstract
5813 - Is MGMT methylation a new therapeutic target for Biliary Tract Cancer?
Presenter: Monica Niger
Session: Poster Display session 2
Resources:
Abstract
5839 - Biliary Tract Cancers in Portuguese families with BRCA gene mutation: a retrospective study.
Presenter: Patricia Pereira
Session: Poster Display session 2
Resources:
Abstract
4338 - Selection of patients with hepatocellular carcinoma for selective internal radiation therapy based on tumour burden and liver function: a post-hoc analysis of the SARAH trial
Presenter: Daniel Palmer
Session: Poster Display session 2
Resources:
Abstract
1700 - Second-line chemotherapy (SLC) in Patients with Advanced Biliary tract and Gallbladder Cancers (ABGC) Prolongs Survival: A Retrospective Population-based Cohort Study
Presenter: Adnan Zaidi
Session: Poster Display session 2
Resources:
Abstract
5562 - Overall survival of patients with hepatocellular carcinoma receiving sorafenib versus selective internal radiation therapy with predicted dosimetry in the SARAH trial
Presenter: Neil Hawkins
Session: Poster Display session 2
Resources:
Abstract
1838 - Multicenter phase II trial of axitinib monotherapy for advanced biliary tract cancer refractory to gemcitabine-based chemotherapy
Presenter: Naohiro Okano
Session: Poster Display session 2
Resources:
Abstract
3641 - Soluble Programmed Death-ligand 1 indicate poor prognosis in hepatocellular carcinoma patients undergoing transcatheter arterial chemoembolization
Presenter: Xiaolu Ma
Session: Poster Display session 2
Resources:
Abstract
2733 - The Prognostic Nutritional Index (PNI) is an independent predictor of survival in advanced biliary cancers (ABC) receiving first-line chemotherapy (1L).
Presenter: Francesco Caputo
Session: Poster Display session 2
Resources:
Abstract
3773 - Impact of centralisation of national cancer services on patient outcomes for hepatobiliary cancers in Ireland 2000 – 2016
Presenter: David O Reilly
Session: Poster Display session 2
Resources:
Abstract