Feasibility of implementing whole genome sequencing into routine oncology care.
Authors: Kasi Pashtoon Murtaza , Dalton Emily , Sharaf Ravi N. , Primiano Michelle , Sternberg Cora N. , Mosquera Juan Miguel , Guevara Daniela , Nanus David M. , Manohar Jyothi , Bapat Bela , Macdonald Theresa , Smith Ryan , Elemento Olivier 
Published: June 2024

e15181

Background: The promise of precision oncology to deliver improved patient outcomes is dependent on the availability and appropriate interpretation of individual patient tumor sequencing results. While routine use and clinical utility for comprehensive genomic profiling (CGP) is growing, there are limited data in the U.S. to support the use of whole genome sequencing (WGS) outside of limited specific indications (i.e. acute myeloid leukemia, pediatric, sarcoma). This study highlights reports on the feasibility from a pilot project offering paired germline/somatic WGS to a cohort of oncology patients at an academic medical center. Methods: Eligible patients included those with an active cancer diagnosis, available tumor, and a treating provider within Weill Cornell. There were no specific restrictions. Providers selected patients with newly diagnosed metastatic cancers, rare tumors, refractory tumors, and/or those with uninformative germline testing for hereditary cancer. Reportable germline findings were pathogenic or likely pathogenic (P/LP) variants in known cancer predisposition genes and/or genes on the American College of Medical Genetics list of reportable secondary findings. Clinical actionability of somatic results was determined using the cBioPortal Database and Oncology Knowledgebase. Ordering providers disclosed results to patients. Barriers to enrollment were explored and addressed. Results: Between January 2021 and December 2023, 82 patients had germline/somatic WGS. The most common tumors included breast (17%), prostate (11%), renal (10%), lung (7%), bladder (7%), and colon (5%), with 48% of the cohort represented by rare tumors. Six cases (7.3%) had insufficient quantity/quality. WGS detected single nucleotide variants in 84% (n = 69) of cases, with 39% (n = 27) of those having clinical actionability in the patient’s tumor. Additional somatic results included copy number variants in 83% (n = 68) and transcriptome variants in 17% (n = 14). P/LP germline variants were found in 17% (n = 14) of cases. Barriers to enrollment included: difficulty identifying which patients would benefit most from WGS, lengthy in-person consent process, limited access to pretest genetic counseling, and difficulty procuring and processing tissue specimens. Availability of reflexive in-house CGP since August 2022 also resulted in decreased uptake of this service. Several interventions were implemented to address the barriers, resulting in an increase in enrollment. Conclusions: Paired germline/somatic WGS identified clinically relevant variants for patients with diverse tumors. Results were used to direct treatment decisions and determine eligibility for clinical trials as well as inform hereditary cancer predisposition. An assessment period after WGS implementation is needed to improve workflow. Further research aims to determine optimal accessibility and utilization of WGS for oncologic patients.