Analysis of hereditary cancer gene variant classifications from ClinVar indicates a need for regular reassessment of clinical assertions

The clinical utility and costs of whole-genome sequencing to detect cancer susceptibility variants-a multi-site prospective cohort study

BACKGROUND

Many families and individuals do not meet criteria for a known hereditary cancer syndrome but display unusual clusters of cancers. These families may carry pathogenic variants in cancer predisposition genes and be at higher risk for developing cancer.

METHODS

This multi-centre prospective study recruited 195 cancer-affected participants suspected to have a hereditary cancer syndrome for whom previous clinical targeted genetic testing was either not informative or not available. To identify pathogenic disease-causing variants explaining participant presentation, germline whole-genome sequencing (WGS) and a comprehensive cancer virtual gene panel analysis were undertaken.

RESULTS

Pathogenic variants consistent with the presenting cancer(s) were identified in 5.1% (10/195) of participants and pathogenic variants considered secondary findings with potential risk management implications were identified in another 9.7% (19/195) of participants. Health economic analysis estimated the marginal cost per case with an actionable variant was significantly lower for upfront WGS with virtual panel ($8744AUD) compared to standard testing followed by WGS ($24,894AUD). Financial analysis suggests that national adoption of diagnostic WGS testing would require a ninefold increase in government annual expenditure compared to conventional testing.

CONCLUSIONS

These findings make a case for replacing conventional testing with WGS to deliver clinically important benefits for cancer patients and families. The uptake of such an approach will depend on the perspectives of different payers on affordability.

Practices and Views of US Oncologists and Genetic Counselors Regarding Patient Recontact After Variant Reclassification: Results of a Nationwide Survey

PURPOSE

Over a 5-year or 10-year period, between 6% and 15% of germline cancer genetic variants undergo reclassification. Up-to-date interpretation can clarify a variant's clinical significance and guide patient management. As the frequency of reclassifications increase, the issue of whether, how, when, and which providers should recontact patients with information about reclassification becomes important. However, the field lacks research evidence and definitive guidance from professional organizations about how providers should recontact patients. We compared the perspectives of US oncologists and cancer genetic counselors (GCs) to describe their practices and views regarding recontact.

MATERIALS AND METHODS

We developed a survey using themes identified from semistructured interviews with oncologists and GCs and administered it in a national sample of oncologists and GCs between July and September 2022.

RESULTS

In total, 634 respondents completed the survey including 349 oncologists and 285 GCs. On frequency of recontacting patients with reclassified results, 40% of GCs reported recontacting often compared with 12.5% of oncologists. Neither group reported recording patient preference for recontact on electronic medical record (EMR). Both groups agreed that all reclassified variants, even those that do not affect clinical management, should be returned to patients. They also reported that recontact via EMR messages, mailed letters, and phone calls from GC assistants were more suitable for downgrades. By contrast, face-to-face meetings and phone calls were preferred for upgrades. Remarkably, oncologists were more likely to endorse face-to-face return of results and were more likely to endorse return through a nongenetics provider compared to GCs.

CONCLUSION

These data on current recontact practices and opinions provide a foundation for developing guidelines with explicit recommendations on patient recontact that can help maximize clinical effect while considering provider preferences for recontact within resource-constrained genomic practice settings.

The role of next-generation sequencing in the examination of signaling genes in Brca1/2-negative breast cancer cases

INTRODUCTION

Breast cancer is the most prevalent malignancy in women worldwide. Although pathogenic variants in the BRCA1/2 genes are responsible for the majority of hereditary breast cancer cases, a substantial proportion of patients are negative for pathogenic variations in these genes. In cancers, the signal transduction pathways of the cell are usually affected first. Therefore, this study aimed to detect and classified genetic variations in non-BRCA signaling genes and investigate the underlying genetic causes of susceptibility to breast cancer.

METHODS

Ninety-six patients without pathogenic variants in the BRCA1/2 genes who met the inclusion criteria were enrolled in the study, and 34 genes were analyzed using next-generation sequencing (NGS) for genetic analysis.

RESULTS

Based on the ClinVar database or American College of Medical Genetics criteria, a total of 55 variants of 16 genes were detected in 43 (44.8%) of the 96 patients included in the study. The pathogenic variants were found in the TP53, CHEK2, and RET genes, whereas the likely pathogenic variants were found in the FGFR1, FGFR3, EGFR, and NOTCH1 genes.

CONCLUSION

The examination of signaling genes in patients who met the established criteria for hereditary breast cancer but were negative for BRCA1/2 pathogenic variants provided additional information for approximately 8% of the families. The results of the present study suggest that NGS is a powerful tool for investigating the underlying genetic causes of occurrence and progression of breast cancer.