The use of O -(2- 18 F-fluoroethyl)-L-tyrosine PET in the diagnosis of gliomas located in the brainstem and spinal cord

<span class="paragraphSection"><div class="boxTitle">Abstract</div><div class="boxTitle">Background.</div>Despite an increasing number of <span style="font-style:italic;">O</span>-(2-¹⁸F-fluoroethyl)-L-tyrosine (¹⁸F-FET) PET studies in supratentorial gliomas, studies regarding the usefulness of ¹⁸F-FET PET in brainstem and spinal cord gliomas to date remain scarce.<div class="boxTitle">Methods.</div>Thirty-six ¹⁸F-FET PET scans were performed in 29 patients with brainstem (<span style="font-style:italic;">n =</span> 29 scans) or spinal cord glioma (<span style="font-style:italic;">n =</span> 7 scans). In 32 of 36 PET scans, a dynamic acquisition was performed. Fifteen scans in 15 patients were performed to assess newly diagnosed lesions, and 21 scans were obtained during follow-up: for diagnosing tumor progression (<span style="font-style:italic;">n =</span> 15 scans in 14 patients) as well as for treatment monitoring (<span style="font-style:italic;">n =</span> 6 scans in 3 patients). Four patients underwent additional serial scans (range, 1–2), and 3 of these 4 patients were examined for more than one indication. Maximum and mean tumor/brain ratios (TBR_max/mean) of ¹⁸F-FET uptake (20–40 min post injection) as well as kinetic ¹⁸F-FET uptake parameters were determined. Final diagnoses were confirmed histologically (54%) or by clinical follow-up (46%).<div class="boxTitle">Results.</div>In all newly diagnosed high-grade (<span style="font-style:italic;">n</span> = 3 patients) and in 5 of 11 patients with low-grade gliomas, ¹⁸F-FET uptake was increased (TBR_max ≥2.5 and/or TBR_mean ≥1.9). In 2 patients with newly diagnosed gliomas without MR contrast enhancement, ¹⁸F-FET PET nevertheless showed increased metabolism. At suspected progression, the combination of TBRs with kinetic ¹⁸F-FET parameters correctly identified presence or absence of progressive disease in 9 of 11 patients (82%).<div class="boxTitle">Conclusions.</div>This preliminary study suggests that ¹⁸F-FET PET adds valuable diagnostic information in brainstem and spinal cord glioma, particularly when the diagnostic information derived from MRI is equivocal.</span>

from Cancer via ola Kala on Inoreader http://ift.tt/2qZ89aK
via IFTTT