Thoracentesis in patients with hematologic malignancy: yield and safety

BACKGROUND: Pleural effusions occur in patients with hematologic malignancies, particularly during periods of hospitalization. Thoracentesis is often performed to diagnose infection and to exclude the presence of complicated parapneumonic effusions. The efficacy and safety of thoracentesis in this setting has not been well-studied. DESIGN: Retrospective chart review of hospitalized patients with hematologic malignancies undergoing thoracentesis. The aim of this study was to assess the role of thoracentesis in establishing a diagnosis of infection in this population and to determine the risk of complications. RESULTS: A total of 100 thoracentesis findings were analyzed in patients with lymphoma (52 patients) and leukemia (27 patients), and in patients who had undergone bone marrow or stem cell transplantation (21 patients). The indication for performing thoracentesis was to exclude infection in 69% of cases. Fever was present in 59% of the patients, and a concomitant lung parenchymal abnormality was present in 69% of cases. Effusions were moderate to large in size (87% of cases), and were both bilateral (62%) and unilateral (38%). Exudates were documented in 83%of the cases. A specific diagnosis was found in 21 patients and was more frequently established in those with lymphoma (31%) compared to the other groups of patients. Diagnoses found included malignancy in 14 cases, chylous effusions in 6 cases, and infection in 1 case. The one patient in whom empyema was found required drainage. The criteria for a parapneumonic effusion were not found in any other patients. The complication rate of 9% (pneumothorax, seven patients; hemothorax, two patients) was comparable to that in other populations of patients. CONCLUSIONS: Despite a high propensity for developing pulmonary infections, hospitalized patients with hematologic malignancies rarely developed complex parapneumonic effusions. The etiology of many of the effusions that occurred in this setting was unclear.