ORIGINAL ARTICLE   

The Quarterly Journal of Nuclear Medicine and Molecular Imaging 2022 March;66(1):74-81

DOI: 10.23736/S1824-4785.19.03173-X

Copyright © 2019 EDIZIONI MINERVA MEDICA

lingua: Inglese

82Rubidium chloride positron emission tomography discrimination of recurrent intracranial malignancy from radiation necrosis

Ephraim E. PARENT ¹, Ila SETHI ² ✉, Jonathon NYE ², Chad HOLDER ², Jeffrey J. OLSON ³, Jeffrey SWITCHENKO ⁴, Funmilayo TADE ⁵, Oladunni O. AKIN-AKINTAYO ², Olayinka A. ABIODUN-OJO ², Akinyemi AKINTAYO ², David M. SCHUSTER ²

¹ Department of Radiology, Mayo Clinic, Jacksonville, FL, USA; ² Department of Radiology and Imaging Sciences, Emory University School of Medicine, Atlanta, GA, USA; ³ Department of Neurosurgery, Emory University School of Medicine, Atlanta, GA, USA; ⁴ Bioinformatics and Biostatistics Shared Resource, Winship Cancer Institute of Emory University, Atlanta, GA, USA; ⁵ Department of Radiology, Loyola University, Chicago, IL, USA

BACKGROUND: Accurate identification and discrimination of post treatment changes from recurrent disease remains a challenge for patients with intracranial malignancies despite advances in molecular and magnetic resonance imaging. We have explored the ability of readily available Rubidium-82 chloride (⁸²RbCl) positron emission tomography (PET) to identify and distinguish progressive intracranial disease from radiation necrosis in patients previously treated with radiation therapy.
METHODS: Six patients with a total of 9 lesions of either primary (N.=3) or metastatic (N.=6) intracranial malignancies previously treated with stereotactic radiation surgery (SRS) and persistent contrast enhancement on MRI underwent brain ⁸²RbCl PET imaging. Two patients with arteriovenous malformations previously treated with SRS, also had brain ⁸²RbCl PET imaging for a total of 11 lesions studied. Histological confirmation via stereotactic biopsy/excisional resection was obtained for 9 lesions with the remaining 2 classified as either recurrent tumor or radiation necrosis based on subsequent MRI examinations. ⁸²RbCl PET time activity curve analysis was performed which comprised lesion SUVmax, contralateral normal brain SUVmax, and tumor to background ratios (TBmax).
RESULTS: ⁸²RbCl demonstrates uptake greater than normal brain parenchyma in all lesions studied. Time activity curves demonstrated progressive uptake of ⁸²RbCl in all lesions without evidence of washout. While recurrent disease demonstrated a greater mean SUVmax compared to radiation necrosis, no statistically significant difference between lesion SUVmax nor TBmax was found (P>0.05).
CONCLUSIONS: ⁸²RbCl PET produces high-contrast uptake of both recurrent disease and radiation necrosis compared to normal brain. However, no statistically significant difference was found between recurrent tumor and radiation necrosis.

KEY WORDS: Glioma; Positron emission tomography; Necrosis