Intestinal Microbiota in Prostate Cancer Patients as a Biomarker for Radiation-INduced Toxicity (IMPRINT)

The IMPRINT-study is a prospective biomarker study assessing the impact of different treatment field sizes and associated radiation doses on the patient's microbiome and metabolome, whereby the link with radiation-induced GI toxicities will be emphasized. Blood, urine and fecal samples will be longitudinally collected at 4 different time points: (1) shortly before, (2) during and (3) shortly after RT treatment, as well as (4) one-month post-RT. To our knowledge, this is the first clinical research project relating the impact of multiple radiation parameters on fecal-, urine- and blood-based biomarkers to risk of GI toxicities in a homogeneously defined study population.

Inclusion criteria

• Histologically proven (initial) adenocarcinoma of the prostate
• Localized (confined to primary site) and/or regional (spread to regional pelvic lymph nodes) disease stage at diagnosis
• Age ≥ 18 years
• RT is an integral part of the treatment - primary, adjuvant or salvage
• WHO performance status 0-2
• Administration of androgen deprivation therapy (ADT) before RT
• Absence of any psychological, familial, sociological or geographical condition potentially hampering compliance with the study protocol and follow-up schedule
• Signed informed consent form (ICF) according to ICH/GCP and national/regional regulations

Exclusion criteria

• Other primary tumor (except for non-melanoma skin cancer) diagnosed < 5 years before enrollment
• Diagnosis of inflammatory bowel disease (e.g. Crohn's disease or ulcerative colitis)
• Administration of systemic therapy during RT other that ADT
• Subjected to antibiotic treatment or medically imposed dietary restrictions < 1 month prior to enrollment
• Body mass index (BMI) > 35
• Administration of pelvic RT < 1 year