NCOG-40. RARE ADVERSE EFFECT OF TEMOZOLOMIDE IN A 65-YEAR-OLD FEMALE WITH GLIOBLASTOMA MULTIFORME: A CASE REPORT

Abstract BACKGROUND Temozolomide, an antineoplastic agent is primarily used to treat certain brain tumors, including glioblastoma multiforme (GBM). Common side effects include nausea, vomiting, constipation, loss of appetite, alopecia (hair loss), headache, fatigue, convulsions and rash. A rare (less than 1%) adverse effect includes aplastic anemia refractory to treatment. Herein we present a case of Temozolomide induced severe bone marrow suppression in a 65-year-old woman with GBM refractory to any treatment CASE PRESENTATION A 65-year-old female presented with dizziness and left-hand numbness. Imaging revealed a right hemisphere mass and she underwent partial resection with pathology showing GBM, IDH wildtype, with CDKN2A/B deletion. She was started on radiation therapy with concurrent temozolomide. After nearly 5 weeks of temozolomide/RT, she developed severe thrombocytopenia/neutropenia with onset of neutropenic fever and severe CMV infection, leading to her demise within a week. DISCUSSION Life threatening refractory cytopenias is a very rare side effect of Temozolomide with a high rate of morbidity/mortality. In the case of our patient, she initially had weekly CBC’s which were stable and hence was switched to a monthly schedule. The patient’s ANC and platelets showed a precipitous drop within a month and ended up with aplastic anemia. The development of this rare complication underscores the importance of increased awareness about this often-fatal adverse event and possibly more frequent monitoring to recognize it early, especially in these patients with an already limited life expectancy. A more tailored approach to monitoring blood work may be needed depending on patient factors. CONCLUSIONS Aplastic anemia refractory to treatment is a rare and life threating adverse effect of temozolomide. The frequency of checking blood work for patients on Temodar has not been definitively established with protocols ranging from once weekly to monthly. Given the potential for this fatal adverse event, it is important to develop better tools to help identify patients in whom more frequent monitoring may be necessary.