Abstract B028: Pan-cancer landscape of somaticBRCA1andBRCA2mutations detected in circulating tumor DNA

Author(s):  
Carin R Espenschied ◽  
Jennifer L Yen ◽  
Tracy Nance ◽  
Richard B Lanman ◽  
Kimberly C Banks
2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Yongliang Zhang ◽  
Yu Yao ◽  
Yaping Xu ◽  
Lifeng Li ◽  
Yan Gong ◽  
...  

AbstractCirculating tumor DNA (ctDNA) provides a noninvasive approach to elucidate a patient’s genomic landscape and actionable information. Here, we design a ctDNA-based study of over 10,000 pan-cancer Chinese patients. Using parallel sequencing between plasma and white blood cells, 14% of plasma cell-free DNA samples contain clonal hematopoiesis (CH) variants, for which detectability increases with age. After eliminating CH variants, ctDNA is detected in 73.5% of plasma samples, with small cell lung cancer (91.1%) and prostate cancer (87.9%) showing the highest detectability. The landscape of putative driver genes revealed by ctDNA profiling is similar to that in a tissue-based database (R2 = 0.87, p < 0.001) but also shows some discrepancies, such as higher EGFR (44.8% versus 25.2%) and lower KRAS (6.8% versus 27.2%) frequencies in non-small cell lung cancer, and a higher TP53 frequency in hepatocellular carcinoma (53.1% versus 28.6%). Up to 41.2% of plasma samples harbor drug-sensitive alterations. These findings may be helpful for identifying therapeutic targets and combined treatment strategies.


2021 ◽  
Vol 23 (2) ◽  
pp. 171-180
Author(s):  
Mauli Shah ◽  
Takeshi Takayasu ◽  
Soheil Zorofchian Moghadamtousi ◽  
Octavio Arevalo ◽  
Melissa Chen ◽  
...  

Author(s):  
Michael J. Duffy ◽  
Eleftherios P. Diamandis ◽  
John Crown

Abstract The detection of cancer at an early stage while it is curable by surgical resection is widely believed to be one of the most effective strategies for reducing cancer mortality. Hence, the intense interests in the development of a simple pan-cancer screening test. Lack of sensitivity and specificity when combined with the low prevalence of most types of cancer types in the general population limit the use of most of the existing protein biomarkers for this purpose. Like proteins, tumor DNA also can be released into the circulation. Such circulating tumor DNA (ctDNA) can be differentiated from normal cell DNA by the presence of specific genetic alteration such as mutations, copy number changes, altered methylation patterns or being present in different sized fragments. Emerging results with test such as CancerSEEK or GRAIL suggest that the use of ctDNA can detect cancer with specificities >99%. Sensitivity however, is cancer type and stage-dependent, varying from approximately 40% in stage I disease to approximately 80% in stage III disease. It is important to stress however, that most of the studies published to date have used patients with an established diagnosis of cancer while the control population were healthy individuals. Although the emerging results are promising, evidence of clinical utility will require demonstration of reduced mortality following evaluation in a prospective randomized screening trial.


2020 ◽  
Vol 18 (7) ◽  
pp. 866-872
Author(s):  
Michael P. Douglas ◽  
Stacy W. Gray ◽  
Kathryn A. Phillips

Background: Clinical adoption of the sequencing of circulating tumor DNA (ctDNA) for cancer has rapidly increased in recent years. This sequencing is used to select targeted therapy and monitor nonresponding or progressive tumors to identify mechanisms of therapeutic resistance. Our study objective was to review available coverage policies for cancer ctDNA–based testing panels to examine trends from 2015 to 2019. Methods: We analyzed publicly available private payer policies and Medicare national coverage determinations and local coverage determinations (LCDs) for ctDNA-based panel tests for cancer. We coded variables for each year representing policy existence, covered clinical scenario, and specific ctDNA test covered. Descriptive analyses were performed. Results: We found that 38% of private payer coverage policies provided coverage of ctDNA-based panel testing as of July 2019. Most private payer policy coverage was highly specific: 87% for non–small cell lung cancer, 47% for EGFR gene testing, and 79% for specific brand-name tests. There were 8 final, 2 draft, and 2 future effective final LCDs (February 3 and March 15, 2020) that covered non–FDA-approved ctDNA-based tests. The draft and future effective LCDs were the first policies to cover pan-cancer use. Conclusions: Coverage of ctDNA-based panel testing for cancer indications increased from 2015 to 2019. The trend in private payer and Medicare coverage is an increasing number of coverage policies, number of positive policies, and scope of coverage. We found that Medicare coverage policies are evolving to pan-cancer uses, signifying a significant shift in coverage frameworks. Given that genomic medicine is rapidly changing, payers and policymakers (eg, guideline developers) will need to continue to evolve policies to keep pace with emerging science and standards in clinical care.


2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Yongliang Zhang ◽  
Yu Yao ◽  
Yaping Xu ◽  
Lifeng Li ◽  
Yan Gong ◽  
...  

A Correction to this paper has been published: https://doi.org/10.1038/s41467-021-21285-2


Diagnostics ◽  
2021 ◽  
Vol 11 (12) ◽  
pp. 2171
Author(s):  
Oscar D. Pons-Belda ◽  
Amaia Fernandez-Uriarte ◽  
Eleftherios P. Diamandis

Circulating tumor DNA (ctDNA) is a new pan-cancer tumor marker with important applications for patient prognosis, monitoring progression, and assessing the success of the therapeutic response. Another important goal is an early cancer diagnosis. There is currently a debate if ctDNA can be used for early cancer detection due to the small tumor burden and low mutant allele fraction (MAF). We compare our previous calculations on the size of detectable cancers by ctDNA analysis with the latest experimental data from Grail’s clinical trial. Current ctDNA-based diagnostic methods could predictably detect tumors of sizes greater than 10–15 mm in diameter. When tumors are of this size or smaller, their MAF is about 0.01% (one tumor DNA molecule admixed with 10,000 normal DNA molecules). The use of 10 mL of blood (4 mL of plasma) will likely contain less than a complete cancer genome, thus rendering the diagnosis of cancer impossible. Grail’s new data confirm the low sensitivity for early cancer detection (<30% for Stage I–II tumors, <20% for Stage I tumors), but specificity was high at 99.5%. According to these latest data, the sensitivity of the Grail test is less than 20% in Stage I disease, casting doubt if this test could become a viable pan-cancer clinical screening tool.


Sign in / Sign up

Export Citation Format

Share Document