Case Report - Volume 2 - Issue 6
18-F-FDG PET/CT Finding of Intramedullary Spinal Cord Metastases from Cerebellar Medulloblastoma - Case report
Fatema Al Sawafi; Naima Al Bulushi*
Department of Nuclear Medicine and Molecular Imaging Centre, Royal Hospital, Oman.
Received Date : Sep 26, 2022
Accepted Date : Oct 31, 2022
Published Date: Nov 21, 2022
Copyright:© Naima Khamis Al Bulushi 2022
A 20- years old female patient, diagnosed case of right cerebellum medulloblastoma, post excision, adjuvant chemotherapy, and radiotherapy in 2018. Presented with right eye swelling in 2021. Brain MRI revealed aright frontal parasagittal mass lesion and left lateral cerebellar mass, highly suggestive of disease recurrence. Total spine MRI showed interval development of new intra-axial lesion at the level of the cervical medullary junction, highly suggestive of Intramedullary spinal cord metastasis (Figure 1).
The patient received palliative radiotherapy for the brain lesions. Post-therapy 18-F-FDG PET/CT scan was done and revealed multiple hypermetabolic lesions seen in the supra and infratentorialregions, representing the known metastatic lesions (Figure 2). In addition, there is interval development of multiple hypermetabolic spinal cord lesions in keeping with Intramedullary spinal cord metastasis (Figure 3). The patient developed lower back pain with neurological deficits. She was referred to palliative team follow-up and palliative radiotherapy to the sacral area.
Intramedullary spinal cord metastasis (ISCM) or what used to be called "Drop metastasis" is rare, constituting only about 8–9% of all CNS metastases [1,2]. Those can be seen in association with extracranial as well as primary intracranial tumors. ISCM from primary intracranial and is very rare . Some CNS primary neoplasms can metastasize and seed inferiorly to the spinal cord spaces, most commonly glioblastoma (GBM), anaplastic astrocytoma, medulloblastoma, ependymoma, and choroid plexus carcinoma. The ISCM from the extracranial tumors most originates from lung cancer (50%), with the remaining from breast cancer (11%), colorectal cancer (3%), kidney cancer (10%), melanomas (8%), and lymphomas (4%) [1,4]. Early suspicion of spinal drop metastasis and early start of treatment is required to improve the neurologic deficit, quality of life, and survival of these patients .
In our case, the 18-F FDG PET/CT scan showed good diagnostic value in detecting spinal cord metastases in apatient with relapsed medulloblastoma. 18-F FDG PET/CT is useful in the diagnosis and characterization of central nervous system tumors and the uptake intensity correlates with the type of tumor, histological grade, and survival outcomes . Although High-quality spinal MR imaging with contrast is considered the method of choice to detect spinal cord metastasis, there is growing evidence with cases published in the literature demonstrating 18F-FDG PET/CT imaging in detecting ISCM.Whole-body 18F-FDG PET-CT can serve as an essential adjunct to MRI in identifying FDG avid metastatic spinal cord lesions and directing an enhanced MRI study for precise localization and confirmation of such tumors . Hence, it is worthstudyingthe future potential clinical utility and diagnostic value of 18 F FDGPET/CT versus MRI in the diagnosis and detectionof ISCM.
Disclosure: No potential conflict of interest relevant to this article was reported.
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