Low Absolute Lymphocyte Count and Addition of Rituximab Confer High Risk for Interstitial Pneumonia In Patients with Diffuse Large B Cell Lymphoma

Abstract

AbstractAbstract 1805 Purpose:Several studies reported pulmonary toxicities in patients with diffuse large B cell lymphoma (DLBCL) receiving rituximab and chemotherapy. This retrospective study aimed to determine the risk factors and clinical characteristics of interstitial pneumonia in patients with DLBCL. Methods:From January 2000 to May 2009, 529 consecutive patients with DLBCL receiving first-line COP- or CHOP-based chemotherapy with or without rituximab in Taipei Veterans General Hospital were enrolled. Interstitial pneumonia (IP) was defined as diffuse pulmonary interstitial infiltrates found on computed tomography scan as well as respiratory symptoms. Patient characteristics and outcome parameters were retrieved via medical chart review. Results:IP was observed in 26 patients (4.9%) and 6 of them were confirmed asPneumocystis jirovecii pneumonia. The median number of chemotherapy course to IP was 4 cycles (range, 1–7). By multivariate logistic regression, absolute lymphocyte count (ALC) less than 1×109/L before treatment (odds ratio [OR] 2.75, 95% confidence interval [CI] 1.23–6.19) and addition of rituximab to chemotherapy (OR 4.56, 95% CI 1.68–12.39) were identified as independent risk factors for IP. In the rituximab-treated patients, low ALC at baseline further increased the risk for IP. Conclusions:Incidence of IP is increased in patients with DLBCL receiving rituximab-containing chemotherapy. Specific subgroup with lymphopenia at diagnosis should receive more attention in detecting this pulmonary complication. [Display omitted] Disclosures:No relevant conflicts of interest to declare.