Neoplasm of unspecified behavior of brain [D49.6], Reason for Study: ^Reason: 42 yo M with recurrent GBM enrolled on clinical trial of re-irradiation, eval extent of disease pre-treatment History: left arm weakness Previously seen right frontal lobe and corpus callosum genu mass which extended toward left frontal lobe with enhancement show more intra tumoral enhancement especially corpus callosum genu area mass on today's scan.There are also more conspicuous enhancements of the right frontal mass especially posterior aspect. However, the maximum diameter of the lesion as well as mass effects toward adjacent ventricle and extents of surrounding edema do not show any significant interval change.Therefore, these interval changes may indicate super imposed effects of Avastin therapy but cannot exclude possibility of tumor progression.Previously seen postoperative changes of the right temporal lobe, insular and the right frontal lobe inferior parietal gyrus with associated overlying dural enhancement are again seen, unchanged. The ventricles, sulci and cisterns are unremarkable.Normal flow voids are identified in the major intracranial vessels. The paranasal sinuses and mastoid air cells are clear.
Interval increase of the extent of enhancing portion of postoperative tumor especially corpus callosum genu portion mass and posterior aspect of right frontal mass. However, these findings are not associated with identifiable interval tumor size increase, nor evidence of increasing mass effects. Differential diagnosis include interval tumor progression and post Avastin therapy effects.