Neurocognitive effects of proton radiation therapy in adults  with low-grade glioma.
To understand neurocognitive effects of proton radiation therapy (PRT) in patients with low-grade glioma, we evaluated 20 patients who received this therapy prospectively and over 5 years with a comprehensive neuropsychological battery. 20 patients were evaluated at baseline and at yearly intervals for up to 5 years with a battery of neuropsychological measures that assessed intellectual, attention, executive, visuospatial and memory functions as well as mood and functional status. We evaluated change in cognitive functioning over time. We analyzed the relationship between cognitive performance and tumor location and also examined whether patients' performance differed from that reported in a study of normative practice effects. Overall, patients exhibited stability in cognitive functioning. Tumor location played a role in performance; those with tumors in the left hemisphere versus in the right hemisphere were more impaired at baseline on verbal measures (p < .05). However, we found greater improvement in verbal memory over time in patients with left than with right hemisphere tumors (p < .05). Results of our study, the first to investigate, in depth, neurocognitive effects of PRT in adults with low-grade gliomas, are promising. We hypothesize that the conformal advantage of PRT may contribute to preservation of cognitive functioning, although larger sample sizes and a longer period of study are required. Our study also highlights the need to consider normative practice effects when studying neurocognitive functioning in response to treatment over time, and the need to utilize comprehensive neuropsychological batteries given our findings that differentiate patients with left and right hemisphere tumors.
Department of Psychiatry and Neurology, Psychology Assessment Center, Massachusetts General Hospital, 1 Bowdoin Square, 7th Floor, Boston, MA, 02114, USA. jsherman@mgh.harvard.edu.
Janet Cohen
http://orcid.org/0000-0001-9782-3158
JC
Sherman
Department of Psychiatry, Psychology Assessment Center, Massachusetts General Hospital, 1 Bowdoin Square, 7th Floor, Boston, MA, 02114, USA.
Mary K
MK
Colvin
Department of Psychiatry, Psychology Assessment Center, Massachusetts General Hospital, 1 Bowdoin Square, 7th Floor, Boston, MA, 02114, USA.
Sarah M
SM
Mancuso
Department of Neurology, Massachusetts General Hospital, 30 Fruit Street, Boston, MA, 02114, USA.
Tracy T
TT
Batchelor
Department of Radiation Oncology, Massachusetts General Hospital, 30 Fruit Street, Boston, MA, 02114, USA.
Kevin S
KS
Oh
Department of Radiation Oncology, Massachusetts General Hospital, 30 Fruit Street, Boston, MA, 02114, USA.
Jay S
JS
Loeffler
Department of Medicine, Massachusetts General Hospital, 30 Fruit Street, Boston, MA, 02114, USA.
Beow Y
BY
Yeap
Department of Radiation Oncology, Massachusetts General Hospital, 30 Fruit Street, Boston, MA, 02114, USA.
Helen A
HA
Shih
D000328:Adult; D001288:Attention / Q000528:radiation effects; D001932:Brain Neoplasms / Q000532:radiotherapy*; D003072:Cognition Disorders / Q000175:diagnosis / Q000209:etiology*; D005260:Female; D005910:Glioma / Q000532:radiotherapy*; D006801:Humans; D007858:Learning / Q000528:radiation effects; D008297:Male; D008875:Middle Aged; D009483:Neuropsychological Tests; D061766:Proton Therapy / Q000009:adverse effects*; D014796:Visual Perception / Q000528:radiation effects; D055815:Young Adult