AMSTERDAM – When predicting the risk of thromboembolism in lymphoma patients receiving chemotherapy, clinicians can rely on a routine diagnostic tool: complete blood count, investigators reported.
A recent study found that high neutrophil to lymphocyte (NLR) and platelet to lymphocyte (PLR) ratios were prognostic for thromboembolism in this setting, reported lead author, of the Clinical Centre of Serbia in Belgrade.
“Because of the presence of a broad spectrum of risk factors [in patients with lymphoma undergoing chemotherapy], some authors have published risk-assessment models for prediction of thromboembolism,” Dr. Otasevic said during a presentation at the annual congress of the European Hematology Association. While the underlying pathophysiology that precedes thromboembolism is complex, Dr. Otasevic suggested that risk prediction may not have to be, noting that NLR and PLR were recently proposed as risk biomarkers.
To test the utility of these potential biomarkers, Dr. Otasevic and his colleagues retrospectively analyzed data from 484 patients with non-Hodgkin and Hodgkin lymphoma who had undergone at least one cycle of chemotherapy at the Clinic for Hematology, Clinical Centre of Serbia. Patients were followed for venous and arterial thromboembolic events from the time of diagnosis to 3 months beyond their final cycle of chemotherapy. NLR and PLR ratios were calculated from complete blood count. Thromboembolism was diagnosed by radiography, clinical exam, and laboratory evaluation, with probable diagnoses reviewed by an internist and radiologist.
The median patient age was 53 years with a range from 18 to 89 years. Most patients were recently diagnosed with advanced disease (21.1% stage III and 42.5% stage IV). Half of the population had high-grade non-Hodgkin lymphoma (50.0%) and slightly more than a quarter had low-grade non-Hodgkin lymphoma (28.3%). Low-grade Hodgkin lymphoma was less common (17.4%) and followed distantly by other forms (4.3%).
Thirty-five patients (7.2%) developed thromboembolic events; of these, 30 had venous thromboembolism (6.2%), 6 had arterial thromboembolism (1.2%), and 1 had both. Patients who experienced thromboembolic events had significantly higher NLR and PLR than patients without thromboembolism, and both ratios were significantly associated with one another.
A positive NLR, defined as a ratio of 3.1 or more, was associated with a relative risk of 4.1 for thromboembolism (P less than .001), while a positive PLR, defined as a ratio of 10 or more, was associated with a relative risk of 2.9 (P = .008). Using a multivariate model, a positive NLR was associated with an even higher relative risk (RR = 4.5; P less than .001).
“NLR and PLR demonstrated significant powerfulness in prediction of future risk of [thromboembolism] in lymphoma patients,” the investigators concluded. “Simplicity, effectiveness, modesty, and practicability qualify these new tools for routine [thromboembolism] prognostic assessment.”
Dr. Otasevic said that he and his colleagues have plans to build on these findings with further analysis involving progression-free and overall survival.
The investigators reported no disclosures.
SOURCE: Otasevic V et al. EHA Congress, .