OBJECTIVES: The standard treatment in patients with newly diagnosed glioblastoma multiforme is radical surgical removal of the tumour, followed by radiotherapy given concurrently with temozolomide (TMZ) and then six cycles of adjuvant TMZ given monthly. It was a retrospective study including patients received more than six cycles of TMZ. This study evaluated outcomes and adverse effects of prescribing adjuvant TMZ for more than six cycles. METHODS: