Genetic counseling in oncology

Downstream Revenue Generated by a Cancer Genetic Counselor

PURPOSE

Enhanced cancer risk reduction measures are recommended for patients with hereditary predispositions to cancer. Providing these services within a healthcare institution (HI) generates downstream revenue (DSR). We evaluated the DSR for our institution after patients were identified to have a pathogenic variant by a genetic counselor (GC).

METHODS

Retrospective chart review identified patients with hereditary breast and ovarian cancer (HBOC) and Lynch syndrome (LS) seen in the UT Southwestern Medical Center Cancer Genetics Clinic between November 1, 2009, and January 31, 2019. All billable encounters were recorded. Total revenue and work relative value units were calculated after patients met with a GC.

RESULTS

Four hundred twenty-five patients with HBOC and LS had financial data available for analysis. After GC visit, DSR totaled $32,798,000 in US dollars (USD). Patients unaffected with cancer (n = 176) generated $8,453,000 (USD). Patients (n = 96) whose first visit to the institution were for GC consultation (naïve patients) generated $5,933,000 (USD). Unaffected, naïve patients (n = 64) generated $3,190,000 (USD) in DSR. The 425 total patients generated 73,957 work relative value units at the institution after their appointment with a GC.

CONCLUSION

GCs bring in substantial DSR for their HI by identifying patients with HBOC or LS. Institution naïve and unaffected patients who continue care at the institution provide additional opportunities to generate DSR. If applied to additional pathogenic variant carriers, GCs can further increase DSR for an HI.

Prevalence of germline mutations in the TP53 gene in patients with early-onset breast cancer in the Mexican population

Background

Heterozygous germline TP53 gene mutations result in Li-Fraumeni Syndrome (LFS). Breast cancer (BC) is the most frequent tumor in young women with LFS. An important issue related to BC in the Mexican population is the average age at diagnosis, which is approximately 11 years younger than that of patients in the United States (U.S.) and Europe. The aim of this study was to determine the prevalence of germline mutations in TP53 among young Mexican BC patients.

Methods

We searched for germline mutations in the TP53 gene using targeted next-generation sequencing (NGS) in 78 BC patients younger than 45 years old (yo) who tested negative for BRCA1/2 mutations. A group of 509 Mexican women aged 45yo or older without personal or family BC history (parents/grandparents) was used as a control.

Results

We identified five patients with pathogenic variants in the TP53 gene, equivalent to 6.4% (5/78). Among patients diagnosed at age 36 or younger, 9.4% (5/55) had pathogenic TP53 mutations. Three of these variants were missense mutations (c.844C > T, c.517G > A, and c.604C > T), and the other two mutations were frameshifts (c.291delC and c.273dupC) and had not been reported previously. We also identified a variant of uncertain clinical significance (VUS), c.672G > A, which causes a putative splice donor site mutation. All patients with TP53 mutations had high-grade and HER2-positive tumors. None of the 509 patients in the healthy control group had mutations in TP53.

Conclusions

Among Mexican BC patients diagnosed at a young age, we identified a high proportion with germline mutations in the TP53 gene. All patients with the TP53 mutations had a family history suggestive of LFS. To establish the clinical significance of the VUS found, additional studies are needed. Pathogenic variants of TP53 may explain a substantial fraction of BC in young women in the Mexican population. Importantly, none of these mutations or other pathological variants in TP53 were found in the healthy control group.