Is there a blood test for cancer
Pro Research Analysisby 
Searched over 200M research papers
Consensus Meter
Blood Tests for Cancer Detection: Current Advances and Insights
Introduction to Blood Tests for Cancer Detection
Early detection of cancer significantly improves treatment outcomes and survival rates. Traditional screening methods like mammography and colonoscopy are limited to specific cancer types and often detect the disease only after symptoms appear. Recent advancements in blood-based tests offer a promising alternative for early and non-invasive cancer detection.
Multi-Analyte Blood Tests: CancerSEEK
One of the most notable advancements in blood-based cancer detection is the development of CancerSEEK. This test combines the analysis of circulating protein biomarkers and tumor-specific mutations in cell-free DNA (cfDNA) to detect eight common cancer types, including ovarian, liver, stomach, pancreatic, esophageal, colorectal, lung, and breast cancers. In a study involving 1005 patients with non-metastatic cancers, CancerSEEK demonstrated a sensitivity range of 69% to 98% and a specificity greater than 99%. This high specificity means that the test has a low false-positive rate, making it a reliable tool for early cancer detection.
Feasibility of Blood Testing Combined with PET-CT
Another study explored the integration of a multicancer blood test with positron emission tomography-computed tomography (PET-CT) imaging. This combination was tested on 10,006 women with no prior history of cancer. The blood test detected 26 cancers, and PET-CT imaging confirmed and localized the disease, leading to surgical removal in nine cases. The study highlighted the safety and feasibility of incorporating blood tests into routine clinical care without causing a significant number of unnecessary follow-up procedures.
Accuracy of Tumor Origin Detection
Determining the tissue of origin (TOO) is crucial for guiding appropriate cancer treatment. A systematic review and meta-analysis of cfDNA-based multi-cancer early detection (MCED) tests showed that the primary site of cancers was accurately identified in 79% of cases. The accuracy varied across cancer types, with colorectal cancers having the highest accuracy and liver & bile duct cancers the lowest . This variability underscores the need for further research to enhance the performance of these tests across different cancer types.
Early Detection with PanSeer
The PanSeer test, which detects cancer based on circulating tumor DNA methylation, has shown promising results in detecting cancer up to four years before conventional diagnosis. In a study involving 605 asymptomatic individuals, PanSeer detected five common types of cancer in 95% of individuals who were later diagnosed, with a specificity of 96%. This early detection capability could significantly improve patient outcomes by identifying cancer at a more treatable stage.
Colorectal Cancer Detection: Fecal Occult Blood Tests
For colorectal cancer, fecal occult blood tests (FOBTs) are commonly used. A study comparing guaiac-based FOBTs (G-FOBT) and immunochemical FOBTs (I-FOBT) found that I-FOBTs had higher participation and detection rates for advanced adenomas and cancer. However, G-FOBTs had slightly better specificity. This suggests that while I-FOBTs may be more effective in detecting colorectal cancer, G-FOBTs could reduce the number of false positives.
Full Blood Count (FBC) for Colorectal Cancer
A systematic review and meta-analysis of full blood count (FBC) components identified several markers associated with colorectal cancer, including red blood cells, hemoglobin, mean corpuscular volume, and white blood cell count. These markers could potentially be used for early detection and referral. However, existing FBC-based prediction models require further validation to ensure their effectiveness.
Conclusion
Blood tests for cancer detection represent a significant advancement in oncology, offering a non-invasive and potentially more comprehensive approach to early diagnosis. Tests like CancerSEEK and PanSeer have demonstrated high sensitivity and specificity, while the integration of blood tests with imaging techniques like PET-CT can enhance diagnostic accuracy. Continued research and development are essential to improve the performance of these tests across various cancer types and stages, ultimately leading to better patient outcomes and reduced cancer mortality.
Sources and full results
Most relevant research papers on this topic