Anemia and thrombocytopenia in patients undergoing chemotherapy for solid tumors: a descriptive study of a large outpatient oncology practice database, 2000-2007

Abstract

Objective: This study was conducted to evaluate data on chemotherapy-associated anemia and thrombocytopenia, and cycle delays in patients with cancer in a community oncology practice.

Methods: Data on adult patients (age > or =18 years) with cancer treated in outpatient oncology clinics throughout the United States between 2000 and 2007 were obtained from a large electronic medical records database. All types of cancer were included, although the focus was on solid cancers (ie, lung, breast, ovarian, head and neck, and colorectal cancers). Chemotherapy regimens were grouped from most to least toxic as follows: platinum-based, anthracycline-based, gemcitabine-based, taxane-based, and all other regimens. Anemia (defined as hemoglobin <11 g/dL), thrombocytopenia (defined as platelet count <150 x 10(9)/L), red blood cell (RBC) and platelet transfusions, and use of erythropoietin-stimulating agents (ESAs) were examined by tumor and regimen type. Cycle delays (>7 days) during chemotherapy were also evaluated.

Results: A total of 47,159 patients were included in the study (58.4% female; mean [SD] age, 60.76 [13.9] years). The most common cancer was breast cancer (19.5%), followed by non-small cell lung cancer (14.9%), colorectal cancer (11.9%), ovarian cancer (3.1%), and head and neck cancer (2.5%). At baseline, 20.9% of patients had anemia and 11.1% had thrombocytopenia. A total of 75,243 chemotherapy regimens were administered. During the course of chemotherapy, from 46.4% to 59.0% of patients developed anemia. The prevalence of thrombocytopenia ranged from 21.9% in patients treated with taxane-based regimens to 64.2% in patients treated with gemcitabine-based regimens. In patients from a single hospital-based outpatient center that had the most complete transfusion data (representing 18.3% of the population), the use of RBC transfusion ranged from 4.5% in patients treated with anthracycline-based regimens to 11.6% in patients treated with platinum-based regimens. ESAs were received at some point during chemotherapy by 49.1% of patients. For those with complete dose information, dose delay occurred in 8.2% of chemotherapy cycles; the mean delay was 17 days.

Conclusion: In this study of anemia and thrombocytopenia in a large cohort of patients undergoing chemotherapy for solid tumors in an outpatient oncology clinic in 2000-2007, the burden of anemia and thrombocytopenia remained high.