Natural History and Growth Patterns of Incidentally Discovered Diffusely Infiltrating Low-Grade Gliomas: A Volumetric Study.
BACKGROUND
Incidentally discovered diffusely infiltrating low-grade gliomas (iDLGGs) are rare findings on neuroimaging that pose a challenge to neurosurgeons. There is a paucity of data regarding the natural history of these lesions, and thus management is controversial. We characterize the growth rates and patterns of iDLGGs in a cohort of patients who underwent serial magnetic resonance imaging before surgical treatment.


METHODS
We performed a retrospective review of all adult patients (≥18 years old) with diffuse low-grade glioma diagnosed at our institution between April 2004 and April 2016. iDLGG was defined as any lesion discovered on computed tomography or magnetic resonance imaging performed for reasons and/or symptoms not attributable to the lesion and confirmed on histopathology as low-grade glioma. Tumor growth rates and patterns of growth were analyzed in patients who had serial imaging available.


RESULTS
Inclusion criteria were met by 15 patients. Mean velocity of diametric expansion was 2.93 mm/year. Of 15 patients, 11 (73.3%) had tumors with an exponential growth pattern, and 4 (26.7%) had a linear growth pattern. Initial tumor volume was positively correlated (r = 0.78) with velocity of diametric expansion.


CONCLUSIONS
iDLGGs grow over time, and most exhibit an exponential pattern of growth. Tumor volume at the time of diagnosis is predictive of a faster growth rate, but not the pattern of growth.
['Opoku-Darko|Michael|M|', 'Eagles|Matthew E|ME|', 'Cadieux|Magalie|M|', 'Isaacs|Albert M|AM|', 'Kelly|John J P|JJP|']
D000328:Adult D000367:Age Factors D001932:Brain Neoplasms D015331:Cohort Studies D018450:Disease Progression D005260:Female D005910:Glioma D006801:Humans D033162:Incidental Findings D008279:Magnetic Resonance Imaging D008297:Male D008875:Middle Aged D060787:Neoplasm Grading D059906:Neuroimaging D012189:Retrospective Studies D012307:Risk Factors D014057:Tomography, X-Ray Computed D055815:Young Adult
Natural history Incidental Low-grade glioma Growth rate Asymptomatic