Glioblastomas (GBMs) are the most aggressive type of brain tumor. GBMs are known for their aggressive and invasive nature because of their ability to easily grow and spread into the surrounding areas of the brain. The annual incidence rate of GBM is 2 to 3 people per 100,000 people in the United States and Europe, and the median survival for patients with an aggressive GBM is 14.6 months. The standard of care for GBMs follows a protocol of surgery, radiation concurrent with the chemotherapeutic drug, temozolomide (TMZ), followed by the administration of up to 6 cycles of TMZ in an adjuvant setting. The objective of this retrospective study was to compare the clinical responses in a patient cohort from varying amount of adjuvant TMZ cycles. Using patient overall survival, the responses to TMZ cycles were tested within different groupings, and the patient covariates were analyzed. The results from the different analyses indicated that survival success of GBM patients is not solely dependent on the number of TMZ cycles, but that other covariates can also affect survival outcomes.