118O - The impact of a prior malignancy on the outcomes of glioblastoma multiforme; SEER based cohort. (118O)

Date 19 November 2017
Event ESMO Asia 2017 Congress
Session CNS tumours
Topics Central Nervous System Malignancies
Presenter Ninos Nissan
Citation Annals of Oncology (2017) 28 (suppl_10): x35-x38. 10.1093/annonc/mdx657
Authors N.E. Nissan1, A.M. Saad2, K.M. Elshewy2, M.J. Al-Husseini2, A.S. Alfaar3
  • 1Oncology Department, Faculty of Medicine, Ain Shams University, 11566 - Cairo/EG
  • 2Oncology Department, Faculty of Medicine, Ain Shams University, Cairo/EG
  • 3Ophthalmology Department, Charité-Universitätsmedizin Berlin (Charité Medical University - Berlin), 13353 - Berlin/DE



Glioblastoma (GBM) is the most common and fatal primary brain tumor in adults. Therefore, there is interest in conducting clinical trials of experimental treatments on patients with GBM, where patients with history of cancer are usually excluded. This practice can affect clinical trials accrual and limit potential therapeutic options for this population. The rationale behind this exclusion is that a history of malignancy could potentially interfere with the study outcomes. However, little is known about its real impact on survival of subsequent GBM.


We used the SEER database of the National Cancer Institute to review patients with GBM diagnosed between 1973 and 2014. We calculated the overall and GBM-specific survival of these patients using unadjusted Kaplan-Meier test and multivariable covariate-adjusted Cox models.


Of the 51,158 GBM patients who were reviewed, 3076 had a prior malignancy. Unadjusted Kaplan-Meier test showed worse overall and GBM-specific survival with patients who had a prior history. However, after adjusting for multiple factors using cox regression models, a prior history was not associated with any significant difference in both overall and GBM-specific survival (HR = 1.025 95% CI = .986-1.066, P = .213 and HR = 1.005 95% CI = .963 - 1.049, P= .810, respectively).


These results should be taken into consideration when putting inclusion/exclusion criteria for GBM clinical trials.

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All authors have declared no conflicts of interest.