Thrombo-Embolism in Patients Receiving Erythropoeitic Stimulating Agents.

There is an increased risk of thrombo-embolism in patients receiving erythropoeitic stimulating agents (ESAs) in the treatment of anemia due to cancer and chemotherapy as well as in patients with chronic renal failure. This fact coupled with evidence of the negative impact on survival in some patients with cancer has prompted a change in the FDA label and restricted the use of ESAs. The exact incidence of thrombo-embolism etiologically related to ESAs in community cancer practices is not known. In this retrospective study we examined the relationship between the administration of ESAs and thrombo-embolism in patients treated after initiating the more conservative use of such agents based on label change.

One-hundred fifty-eight cases of thrombo-embolism and central catheter occlusion observed between August 2007 and May 2009 were identified through the electronic medical records (EMR) database at Gabrail Cancer Center. Likewise, all patients who received ESAs during the same time period were identified through the EMR. Records of all patients were examined to verify diagnosis, confirm data, and validate timing of administration of the ESAs.

A total of 496 patients received ESAs during the study period. Of these patients, 158 developed thrombo-embolism or central catheter occlusion. There were 128 patients with cancer and 34 had non-cancerous diagnoses with mean age of 62 and M:F of 4:1. Of the 128 patients with cancer 99 patients developed uncomplicated catheter occlusion and 39 developed DVT and/or pulmonary embolism. Seventy-four of the 99 patients who had catheter occlusion had received ESAs (74%). Of the 39 patients who developed DVT and pulmonary embolism 26 were treated with ESAs (67%). Of the 99 patients who developed catheter occlusion 51 (51%) received ESAs prior to catheter occlusion of the 39 patients who had DVT and PE 19 (48%) of the events happened after ESAs were initiated. The total number of patients who received ESAs during the same time period was 496. Only 32% of these patients developed thrombo-embolism and catheter occlusion. However, only 114 patients (23%) experienced a thrombotic episode after ESAs were initiated. This did not differ significantly from the incidence of thrombosis either in the form of catheter occlusion, deep vein thrombosis, or pulmonary embolism in this patient population.

Although some studies have shown an increased incidence of thromboembolism in cancer patients receiving ESAs, such studies were performed at a time when the use of these agents was more liberal in order to increase the Hb to normal or above normal levels. In this community-based practice study that included patients treated after the label change, the incidence was not greater than that seen in cancer patients not receiving ESAs. However, a prospective clinical trial is needed to confirm these findings especially after the label change that has restricted the use of ESAs.

³(Transmittal 80, Pub 100-03 Medicare National Coverage Decision, eff. 7/30/2007)

No relevant conflicts of interest to declare.