Colorectal carcinoma prevalence not increased in Birt-Hogg-Dube syndrome

Last Updated: 2020-01-03

By Reuters Staff

NEW YORK (Reuters Health) - The prevalence of colorectal carcinoma does not appear to be increased in patients with Birt-Hogg-Dube (BHD) syndrome, researchers from the Netherlands report.

Colon polyps and colorectal carcinoma (CRC) have been reported in multiple patients with BHD, a genodermatosis caused by mutations in the FLCN gene, but no large study has confirmed these associations. Nevertheless, Dutch guidelines recommend colorectal surveillance every five years starting at age 45 for BHD patients in families with at least one patient with both BHD and CRC.

Dr. Irma van de Beek and colleagues from Amsterdam UMC and Vrije Universiteit Amsterdam evaluated the association of BHD with colorectal neoplasms by comparing the occurrence of colon polyps and CRC between 399 Dutch BHD patients and 382 of their family members without the familial FLCN mutation.

Overall, 24 colorectal carcinomas occurred in 22 individuals, with no significant difference in frequency between the group with BHD (3.3%) and the group of unaffected family members (2.4%) (p=0.52), according to the online report in British Journal of Cancer.

The groups did not differ in age at first CRC, diameter and differentiation of the first CRC, or location of the CRC.

In contrast, at least one colorectal polyp was diagnosed in significantly more individuals with BHD (11.8%) than in those with a normal FLCN (5.8%) (p=0.004).

The groups did not differ in the median number of polyps per individual, the type of polyps, grade of dysplasia, or location of the polyps.

"In conclusion, our data do not provide evidence for an increased risk for CRC in BHD, in line with the observations of a previous cohort study," the authors conclude. "If there is an association, it is likely to be small and it is doubtful whether surveillance with colonoscopy is indicated."

"Although it would be preferable to verify our observations by a prospective cohort study, based on our findings and the existing data from previous cohorts, we suggest to no longer advise patients with BHD to undergo surveillance by colonoscopy, unless indicated by a family history of CRC, in accordance with local guidelines," they add.

Dr. van de Beek was unavailable for comment.

SOURCE: https://go.nature.com/2rTENzV British Journal of Cancer, online December 20, 2019.