EPID-11. OCCURRENCE OF SYSTEMIC CANCER IN PATIENTS WITH GLIOBLASTOMA: POPULATION CHARACTERIZATION AND COMPLICATIONS

Abstract

Abstract It is unclear how the diagnosis of a second cancer influences the treatment and complications of patients with glioblastoma (GBM). A chart review of adults with primary or secondary GBM and another systemic cancer seen in the last five years was performed. Demographic data, thromboembolic events, cytopenia and deviations from the standardized GBM treatment protocol (EBRT with 60 Gy plus concurrent temozolomide followed by adjuvant temozolomide) were analyzed. Exclusion criteria was the diagnosis of genetic syndromes that predispose to tumorigenesis. A total of 56 GBM patients with 61 systemic cancers were identified. The most common systemic cancers were breast and prostate each representing 27 %. Men were 55% of patients (p=0.3) but older (69+11 years, p=0.003) than when compared to CBTRUS data. Systemic cancer was diagnosed before GBM in 82% of the cases. Age at the diagnosis of systemic cancer was 64 +11 years. Patients with systemic cancer diagnosed prior to GBM, had shorter survival (1.15+1.08 years versus 4.4+ 3.4 years, p < 0.001), but survival was not shorter than expected when compared to historical survival of GBM. Thromboembolism was seen in 27% of patients, only once it was seen before the diagnosis of GBM. Although all patients with hematological malignancies had low platelets, thrombocytopenia was not associated to prior chemotherapy. Deviation of GBM treatment was seen in 15% of the cases, a delay in the systemic cancer once. This is the largest documented series of patients with GBM and systemic cancer. We conclude that although this population is older than expected, thromboembolism rates and survival are similar to the literature for patients with GBM. In the light of all those considerations, patients with GBM and the diagnosis of a systemic cancer should be treated according to guideline.