Clinical trial NCT03417258: Phytoestrogens and Colonic Adenomatous Polyps
Official title: Bioavailability of Phytoestrogens and Prevalence of Adenomatous Polyps in Human Colon
Study type: OBSERVATIONAL
Overall status: COMPLETED
Conditions: Intestinal Polyps
Keywords: phytoestrogens
isoflavones
adenomatous polyps
microbiome
Lead sponsor: University of Bari
Sponsor class: OTHER
First posted: 2018-01-31
Enrollment: 30
Sex: ALL
Minimum age (years): 50
Maximum age (years): 75
Standard ages: ADULT
OLDER_ADULT
Accepts healthy volunteers: no
Observational model: OTHER
Time perspective: CROSS_SECTIONAL
Sampling method: NON_PROBABILITY_SAMPLE
Study population: All patients (aged between 50 and 75 years) undergoing colonoscopy within 3 months from the study evaluation.

Brief summary: INTRODUCTION: The data obtained by experimental studies about the influence of phytoestrogens on colorectal cancer (CRC) have been very promising. On the other hand, clinical trials have produced conflicting results. The literature suggests that some subclasses of phytoestrogens may have protective effects against CRC and colon adenomas, but most of these results come from population studies based on the dietary intake of phytoestrogens. On these premises, it is possible to hypothesize that the variability of the data reported in the literature may be due to the fact that the real absorption of phytoestrogens (by assessing their concentration in the serum or urine) and/or the ability of the single individual of producing equol was not evaluated.

PURPOSE: In the present study, the association between the phytoestrogens intake and the prevalence of colon adenomas was evaluated not only on the basis of the simply dietary intake but also on the measurement their intestinal absorption. Moreover, a specific evaluation of equol production by the intestinal flora was performed. Finally, intestinal bacteria involved in equol production were evaluated.

Detailed description: MATERIALS AND METHODS: Patients with sporadic colon adenomas were enrolled in group I (case) and patients without sporadic colorectal adenomas matched for sex, age and BMI were enrolled in group II (control). All participants underwent the following evaluations: BMI, dietary history (for quantitative and qualitative analysis of dietary habits), quantitative analysis of phytoestrogens (by dietary questionnaires), medications (chronic assumption of aspirin at low doses), characteristics of the polyps (for a calculation the cancer risk), analysis of urinary excretion of phytoestrogens \[by high pressure liquid chromatography (HPLC)\] and intestinal flora \[by mass spectrometry with Matrix Assisted Laser Desorption Ionization Time-of-Flight (MALDI-TOF) technology\]. At the enrolment, patients will be invited to assume a standard quantitative of phytoestrogens at 8:00 a.am. and collect both a fecal sample and the urine of the following 24 hrs.

Eligibility criteria: Inclusion Criteria:

* subjects of both sexes aged between 50 and 75 years
* colonoscopy within 3 months from the study evaluation

Exclusion Criteria:

* age \< 50 and \> 75 years
* previous diagnosis of colon cancer or inflammatory bowel diseases (IBD)
* Hereditary intestinal tumors (FAP, HNPCC, ...)
* ongoing infections
* intake, in the last 4 weeks, of drugs that alter the intestinal bacterial flora
* creatinine clearance below 60 ml/min
* liver failure

Primary outcomes:
measure: Phytoestrogen absorption
timeFrame: one day
Secondary outcomes:
measure: Intestinal microbiota
timeFrame: one day
Other outcomes:
Locations:
city: Bari
country: Italy
facility: Policlinic Hospital
Study officials:
affiliation: University of Bari
name: Alfredo Di Leo
role: STUDY_CHAIR
References:
citation: Xu X, Harris KS, Wang HJ, Murphy PA, Hendrich S. Bioavailability of soybean isoflavones depends upon gut microflora in women. J Nutr. 1995 Sep;125(9):2307-15. doi: 10.1093/jn/125.9.2307.
citation: Atkinson C, Frankenfeld CL, Lampe JW. Gut bacterial metabolism of the soy isoflavone daidzein: exploring the relevance to human health. Exp Biol Med (Maywood). 2005 Mar;230(3):155-70. doi: 10.1177/153537020523000302.
citation: Jin H, Leng Q, Li C. Dietary flavonoid for preventing colorectal neoplasms. Cochrane Database Syst Rev. 2012 Aug 15;2012(8):CD009350. doi: 10.1002/14651858.CD009350.pub2.
citation: Kocic B, Kitic D, Brankovic S. Dietary flavonoid intake and colorectal cancer risk: evidence from human population studies. J BUON. 2013 Jan-Mar;18(1):34-43.
citation: Setchell KD, Brown NM, Lydeking-Olsen E. The clinical importance of the metabolite equol-a clue to the effectiveness of soy and its isoflavones. J Nutr. 2002 Dec;132(12):3577-84. doi: 10.1093/jn/132.12.3577.