Oncogenic Variants Identified in ~10 Percent With Appendix Cancer

TUESDAY, Nov. 22, 2022 (HealthDay News) -- About 10 percent of patients with appendix cancer (AC) who undergo testing for hereditary cancer disposition harbor a gene sequence variation associated with cancer susceptibility, according to a study published online Nov. 11 in JAMA Oncology.

Andreana N. Holowatyj, Ph.D., from the Vanderbilt University Medical Center in Nashville, Tennessee, and colleagues examined the prevalence and spectrum of inherited cancer susceptibility gene sequence variations in a cohort of patients with AC who underwent germline genetic testing of 14 cancer susceptibility genes. The cohort included 131 patients with AC.

The researchers identified 16 deleterious sequence variations in 15 patients (11.5 percent). When limited to the 74 patients with AC as the first and only primary tumor, eight patients (10.8 percent) had at least one deleterious sequence variation in a cancer susceptibility gene. Six patients (4.6 percent) had a deleterious sequence variation in MUTYH (five monoallelic and one biallelic). Four patients (3.1 percent) had Lynch syndrome and had a sequence variation in the MLH1 gene; three were aged 50 years or older at AC diagnosis. Deleterious sequence variations in other cancer predisposition genes (APC, CHEK2, SMAD4, and TP53) were seen for five patients (3.8 percent).

"These findings support the consideration of genetic testing for all patients with appendix cancer irrespective of age or family history," the authors write. "The consideration of a more systemic sequencing effort for all patients with appendiceal cancer may provide important evidence toward tailoring genes selected for germline genetic testing for appendiceal cancer across specific patient groups."

One author disclosed financial ties to Ambry Genetics.

Abstract/Full Text (subscription or payment may be required)