CLL Diagnosis Preceded by Decades of Increased Infection Susceptibility
This article was originally published by Cancer Therapy Advisor
Chronic lymphocytic leukemia (CLL) is well known for its close relationship with immune dysfunction, with around a third of patient deaths attributable to bacterial or viral infections. And while the relative risk of death due to the malignancy itself has declined over the past few decades, the risk of death from infection among those with CLL has remained constant, some research suggests.1
Infections often precede a formal diagnosis of CLL. Patients are known to suffer severe infections such as pneumonia up to 10 years prior to being diagnosed. Such findings pose a chicken-or-egg conundrum: Does the immune dysfunction occur prior to the development of CLL, potentially driving the development of the malignancy, or do CLL cells arise first, causing immune dysfunction long before the disease is diagnosed?
Shedding fresh light on this question, a group of Danish researchers undertook a retrospective analysis of nationwide Danish cancer registries and examined CLL patients’ history of antimicrobial use as a proxy for infection susceptibility. In line with previous studies, the researchers found that antimicrobial use began to rise 6 years prior to CLL diagnosis.
But even before then, patients with leukemia had used more macrolides, antimycotics, and antivirals than healthy controls for up to 22 years before they were diagnosed. The authors wrote that this time window jibes well with the theory that immune dysfunction, and/or infections, develop prior to CLL and could potentially play a causal role in driving the disease. The findings were published last month in Leukemia.2