Temozolomide Induced Bone Marrow Suppression- a Single Institution Outcome Analysis and Review of Literature

Abstract

Background: Severe myelosuppression (MS) and bone marrow failure (BMF) are rare but well characterized adverse effect of temozolomide (TMZ). The existing literature is limited to case reports and data reported to regulatory agencies, which usually describe very severe cases and lack long term and detailed follow-up.Methods: We identified cases of myelosuppression attributed to TMZ seen at the Mayo clinic, from 1998-2014. We also performed a literature (PubMed) search to identify published cases of TMZ induced MS and BMF. TMZ induced MS was defined as a decrease in at least 2 cell lines below normal that was clinically attributable to TMZ and persisted for > 28 days after the last TMZ dose. Severe MS was defined as bone marrow cellularity of <25% or at least 2 of: a) reticulocyte count <40,000/µL b) absolute neutrophil count (ANC)<500/ µL c) platelets <20,000/µL. Very severe MS was defined by an ANC <200/ µL.Results: A total of 15 Mayo patients and 10 published cases were identified. The baseline characteristics of patients are shown in table 1. The median interval between initiation of TMZ and diagnosis of MS was 48 days (range 26-121). The hematologic outcomes of the group are shown in table 2. Seventeen patients developed neutropenic fever, 4 had severe sepsis, and 6 experienced bleeding complications. Kaplan-Meier recovery curves for each cell line are shown in the figure. Myelosuppression was fatal in 3 cases. Most patients recovered their ANC (median-62 days, range 28-180). Persistent thrombocytopenia was seen in 19 patients, without evidence for clonal evolution or myelodysplasia. Four patients remain dependent on growth factor support (G-CSF and thrombopoietin agonists).Conclusion: MS is usually a non-fatal complication of TMZ. Most cell lines recover spontaneously and adequately with the exception of platelets, which can remain significantly suppressed for prolonged periods. Infectious complications are very common. Most patients respond to supportive care, including the use of growth factors. [Display omitted] [Display omitted] [Display omitted] DisclosuresNo relevant conflicts of interest to declare.