Fecal immunochemical tests may be as effective as colonoscopies when it comes to detecting colorectal cancer among first-degree relatives of patients with colorectal cancer (CRC).

First-degree relatives of patients with nonsyndromic colorectal cancer (CRC) are at higher risk of developing CRC than the general population and personal risk in these individuals has mostly been related to the age of the index case at diagnosis, degree of kinship, and number of relatives affected.

Gastroenterologists at the Universidad de La Laguna (Tenerife, Spain) conducted a prospective study of 1,918 first-degree relatives of patients with CRC who were randomly assigned to receive a single colonoscopy examination or three fecal immunochemical tests (FITs). One test was done per year for three years; with a cutoff equal to or greater than 10 μg hemoglobin/g feces which corresponds to 50 ng hemoglobin/mL buffer.

Individuals assigned to the FIT group were provided with a single OC-Sensor Fecal Immunochemical Test kit (Eiken Chemical; Tokyo, Japan). The samples were analyzed on Eiken’s automated machine for detecting hemoglobin in stool samples. Participants were asked to keep fecal samples at 4 °C and return them within five days after sampling. Colonoscopies were performed by four experienced endoscopists who were blinded to group assignment.

The repeated FIT screening detected all colorectal cancers and 61% of advanced adenomas, thus proving equivalent to one-time colonoscopy screening in terms of diagnostic yield and tumor staging. However, colonoscopy was superior to the FIT strategy for the detection of non-advanced adenomas. The usefulness of FIT screening as an alternative to colonoscopy in the familial risk population will ultimately depend on the capacity of FIT to improve screening uptake.

The authors concluded that the results of their randomized trial demonstrated in asymptomatic first-degree relatives of patients with CRC that screening with FIT is equivalent to one-time colonoscopy for the detection of advanced neoplasia. In addition, it also provides evidence for the benefit of repeated FIT screening in terms of colonoscopy resources.

Enrique Quintero, MD, PhD, the lead author of the study said, “In our study, repeat FIT screening detected all colorectal cancers in asymptomatic first-degree relatives of patients with colorectal cancer. These findings suggest that FIT screening should potentially be considered for familial screening, especially in populations where colonoscopy capacity is limited and/or compliance with colonoscopy is a concern.” The study was published in the November 2014 issue of the journal Gastroenterology.

Related Links:
Universidad de La Laguna 
Eiken Chemical