A Swedish study led by Karolinska Institutet and Danderyd Hospital, published in Nature Communications, reports that a simple blood test may assist in detecting cancer in patients presenting with non-specific symptoms such as fatigue, pain, or weight loss.
Diagnosing the cause of non-specific symptoms can be challenging, as they may indicate cancer, other serious conditions, or minor issues. Researchers from Karolinska Institutet, Danderyd Hospital, Örebro University, KTH Royal Institute of Technology, and SciLifeLab at Uppsala University investigated whether blood proteins could provide early diagnostic indicators.
The study analyzed blood samples from nearly 700 patients referred to diagnostic centers in Sweden. These samples were collected prior to diagnostic investigations. Utilizing proteomics, a method for large-scale protein analysis, 1,463 different plasma proteins were measured. A specific combination of proteins, or a protein signature, was identified and linked to a cancer diagnosis.
According to Mikael Åberg, associate professor at Uppsala University, the study demonstrates the capability of large-scale proteomics to extract clinically relevant information from small blood volumes.
Researchers subsequently developed a model capable of distinguishing cancer patients from those with other conditions, including inflammatory, autoimmune, or infectious diseases, with high precision. Charlotte Thålin, senior physician at Danderyd Hospital and adjunct professor at Karolinska Institutet, noted that the control group's composition, including patients with other serious conditions causing similar symptoms, reflects clinical assessment challenges.
The researchers emphasize that this method is intended to support, rather than replace, established diagnostic tools like imaging or biopsies. It could aid in prioritizing patients for further diagnostics, such as PET-CT, while potentially reducing unnecessary investigations for those without cancer, as stated by Fredrika Wannberg, a resident at Danderyd Hospital.
Additional studies are required before the method can be implemented clinically, with the next phase involving testing in primary care settings, where cancer incidence is lower than in specialist care. The research received funding from organizations including the Swedish Research Council, the Knut and Alice Wallenberg Foundation, and the Jochnick Foundation.