Fig. 5.

Brainstem invasion and overall survival in postmortem GBMs. (A) The overall survival of patients in the current cohort was integrated with published data from several decades ago,^5,6,11 and sorted by the presence or absence of brainstem invasion. Red circles or squares = cases from current cohort; blue circles or yellow squares = cases from older published cohorts. P-value was calculated via log-rank test. Bars = median survival. (B) Multiple large tracts of myelinated axons extend from the cortex through the midbrain into the pons, including fronto-pontine (orange), corticospinal (green), parieto-pontine (blue), and occipito-pontine (purple). (Temporo-pontine tracts are above and below the plane of the diagram.) Such tracts allow a GBM, arising anywhere in the cerebrum, direct access to vital brainstem structures.