From the Research
Yes, D-dimer can be elevated in patients with lung cancer, and high levels are associated with increased risk of mortality and venous thromboembolism, as shown in a recent study published in 2022 1. This elevation occurs because cancer cells can activate the coagulation system, leading to increased fibrin formation and subsequent degradation, which produces D-dimer fragments. In lung cancer specifically, studies have shown that D-dimer levels are often higher compared to healthy individuals, with more advanced stages of cancer typically associated with higher D-dimer values. The elevation may result from tumor-induced activation of the clotting cascade, inflammatory responses, or direct invasion of blood vessels by tumor cells. Some key points to consider include:
- Elevated D-dimer in lung cancer patients is clinically significant as it may indicate a hypercoagulable state and increased risk for venous thromboembolism (VTE), a common complication in cancer patients.
- While D-dimer testing is not used for lung cancer diagnosis, persistently elevated levels in a patient with risk factors might warrant further investigation for malignancy, especially if other causes of elevation (such as recent surgery, infection, or pregnancy) have been ruled out.
- A meta-analysis and systematic review of all available cohort studies were performed on the link between circulating D-dimer levels and survival of lung cancer patients, and the results showed that high D-dimer levels contribute to death in tumor group (HR 1.62,95% CI: 1.39-1.88, I2 = 75.0%) 1.
- External validation of 540 patients also showed that high levels of D-dimer showed a higher risk of overall mortality (HR 1.39,95% CI: 1.13-1.72, p = 0.002) and VTE events (HR 3.98,95% CI: 1.99-8.70, p = 0.002) in lung cancer patients 1. However, it's worth noting that D-dimer levels can be influenced by various factors, and the relationship between D-dimer and lung cancer prognosis is still being researched, with some studies suggesting that D-dimer may be a useful prognostic marker 2, 3. Additionally, the diagnostic performance of D-dimer in predicting venous thromboembolism and acute aortic dissection has been assessed, and the results showed that D-dimer is useful not only to rule out but also to rule in venous thromboembolism and acute aortic dissection with an at least moderate discriminatory ability, both in patients with and without cancer 4. Current guidelines recommend the use of evidence-based algorithms for the diagnosis and treatment of deep vein thrombosis and pulmonary embolism, and D-dimer tests may reduce the need for subsequent diagnostic procedures 5.