An analysis of the impact of annual cancer genetic testing guideline updates on a past patient population

Abstract

Germline genetic testing for cancer predisposition genes has become an essential component of cancer treatment and risk reduction. The National Comprehensive Cancer Network (NCCN) releases annual genetic testing guidelines that identify characteristics of patients that could be affected by a hereditary cancer syndrome. These guidelines have broadened over time and the implications for past patients of cancer genetics clinics are not well understood. This study is a retrospective chart review aimed at determining the percentage and characteristics of past patients that meet updated NCCN guidelines (Breast, Ovarian, and Pancreas [BOP] v1.2022 and Colorectal [CRC] v1.2021), patients that attended a follow-up appointment, and patients who went on to receive genetic testing. Clinical data and characteristics were compared between the study population as a whole and the cohort of patients that met updated NCCN guidelines BOP v1.2022 and CRC v1.2021. The study population consisted of 280 patients with 76 (27.1%) patients meeting updated NCCN guidelines BOP v1.2022 and CRC v1.2021. The year of initial cancer genetic counseling appointment was statistically significant (p = 0.023) with patients more likely to meet NCCN guidelines BOP v1.2022 and CRC v1.2021 with earlier initial cancer genetic counseling appointments. In the cohort that met updated NCCN guidelines BOP v1.2022 and CRC v1.2021, the most common reason was a change in the NCCN guidelines (BOP or CRC) (54/76, 71.1%) with triple-negative breast cancer diagnosed at any age being the most impactful guideline change (19/54, 35.2%). Twenty-one patients attended a follow-up appointment (7.5%) and of those that received genetic testing (17/21, 81%) most received negative results (13/17, 61.9%), with one pathogenic, low penetrance result (1/17, 5.9%, CHEK2 p.I157T). Provider-initiated follow-up was attributed to most follow-up appointments (16/21, 76.2%) implying patients do not tend to follow-up on their own. Education to non-genetics providers as well as targeted implementation of follow-up protocols possibly managed by genetic counseling assistants and utilizing electronic medical record (EMR) patient messaging could lead to improved patient follow-up.

Keywords: cancer genetics; genetic services; national comprehensive cancer network; patient follow‐up; predictive genetic testing; referral practices.