Clinical correlates of severe thrombocytopenia from temozolomide in glioblastoma patients.

Abstract

This study was done retrospectively to evaluate rates of thrombocytopenia and their clinical impact during chemo-radiotherapy for glioblastomas and to elucidate associated clinical factors. Sixty-four patients who received temozolomide chemotherapy at our institution were included. Thirty-five patients received full dose chemo-radiotherapy as per the STUPP protocol (Group A) and nine patients received abbreviated radiotherapy with concurrent chemotherapy (Group B). Twenty patients received temozolomide alone with an intended twelve cycles of therapy for first relapse at least six months after completion of adjuvant chemotherapy (Group C). In group A, twenty-seven of thirty-five (77%) patients completed chemo-radiotherapy phase. 14% had grade 3-4 thrombocytopenia leading to discontinuation. Sixteen of twenty-seven (59%) patients completed adjuvant chemotherapy. There were no grade 3-4 thrombocytopenias but 4% discontinued due to grade 2 thrombocytopenias. In Group B, four out of nine (45%) patients completed chemo-radiotherapy phase. 11% had grade 3-4 thrombocytopenias and discontinued treatment. Three out of four (75%) patients completed adjuvant chemotherapy. Of these, 75% had grade 3-4 thrombocytopenias but none discontinued. Lastly, in Group C, eight out of twenty (40%) patients completed with 10% discontinuing due to thrombocytopenias and the rest due to disease progression. In exploratory analyses, being female increased the risk of myelosuppresion and there was a trend noticed in patients having a higher body surface area. Our toxicity data was within range of the literature. We identified the group of patients that have increased thrombocytopenia risk. Larger pooled retrospective series and prospective studies are required. This article is protected by copyright. All rights reserved.