Indian Journal of Nuclear Medicine

LETTER TO THE EDITOR
Year
: 2017  |  Volume : 32  |  Issue : 1  |  Page : 81--82

Subependymal spread of glioblastoma multiforme in positron emission tomography/computed tomography


Agostino Chiaravalloti1, Orazio Schillaci1, Pasqualina Sannino2,  
1 Department of Biomedicine and Prevention, University Tor Vergata, Rome, Italy
2 IRCCS Neuromed, Pozzilli, Italy

Correspondence Address:
Agostino Chiaravalloti
IRCCS Neuromed, Pozzilli, IS
Italy




How to cite this article:
Chiaravalloti A, Schillaci O, Sannino P. Subependymal spread of glioblastoma multiforme in positron emission tomography/computed tomography.Indian J Nucl Med 2017;32:81-82


How to cite this URL:
Chiaravalloti A, Schillaci O, Sannino P. Subependymal spread of glioblastoma multiforme in positron emission tomography/computed tomography. Indian J Nucl Med [serial online] 2017 [cited 2021 Apr 18 ];32:81-82
Available from: https://www.ijnm.in/text.asp?2017/32/1/81/198504


Full Text

Sir,

In a paper published recently aimed to compare the diagnostic reliability of (18F)-L-dihydroxyphenylalanine (18F FDOPA) versus magnetic resonance imaging (MRI) in primary brain tumors,[1] positron emission tomography/computed tomography (PET/CT) proved to be superior to MRI in evaluating recurrence and residual tumor tissue.[1] Here, we report a case of recurrent glioblastoma multiforme (GM) of the left frontal lobe. The patient was admitted to our center after a seizure episode in the right upper limb and a history of cognitive and memory impairment, apathy, and depression. The patient underwent surgical resection of the primary tumor and then underwent an 18F FDOPA PET/CT examination 2 months after surgery.

In [Figure 1] (a, arrows), the axial PET/CT performed 15 min after the injection of 210 MBq of 18F FDOPA with a low-dose CT scan of the head for attenuation correction and reconstruction of PET images performed by means of ordered subset expectation maximization algorithm with four iterations and twenty subsets show an increased uptake of the radiotracer in two subependymal areas around the right lateral ventricle (arrows) which was evident as intense contrast enhancement on T1-weighted MR images (b and c, arrows). These findings have been confirmed in a subsequent MRI scan performed after 3 months, showing an increase in size of the subependymal findings [Figure 1]. In [Figure 1]a, the “*” highlights an area of 18F FDOPA uptake that is consistent with inflammatory process at the surgical site.[2] Informed consent was obtained from the patient.{Figure 1}

[18F] FDOPA PET/CT has been proposed for the study of primary brain tumors and a higher diagnostic accuracy of this imaging modality as compared to contrast-enhanced MRI, has been reported.[1] Multifocal lesions with subependymal or subarachnoid spread is a quiet rare condition representing approximately 1.2% of recurrence in GM and approximately 15% of the intracranial dissemination of GM in adults.[3] If one considers that subependymal and periventricular enhancement in MRI could be related to several benign conditions (periventricular vascular structures, arteriovenous malformations, collateral venous drainage, etc.),[4] this report highlights that 18F FDOPA PET could be used in addition to conventional imaging modalities for staging and detection of GM and its recurrence at this unusual site for its capability to discriminate between benign and pathological tissue.

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.

References

1Jora C, Mattakarottu JJ, Aniruddha PG, Mudalsha R, Singh DK, Pathak HC, et al. Comparative evaluation of 18F-FDOPA, 13N-AMMONIA, 18F-FDG PET/CT and MRI in primary brain tumors - A pilot study. Indian J Nucl Med 2011;26:78-81.
2Chiaravalloti A, Fiorentini A, Villani V, Carapella C, Pace A, Di Pietro B, et al. Factors affecting 18F FDOPA standardized uptake value in patients with primary brain tumors after treatment. Nucl Med Biol 2015;42:355-9.
3Parsa AT, Wachhorst S, Lamborn KR, Prados MD, McDermott MW, Berger MS, et al. Prognostic significance of intracranial dissemination of glioblastoma multiforme in adults. J Neurosurg 2005;102:622-8.
4Reeder MM. Reeder Felson's Gamuts in Radiology. 2003;4th ed. New York Springer 861-930.