PT  - JOURNAL ARTICLE
AU  - Nabavizadeh, Ali
AU  - Bagley, Stephen J.
AU  - Doot, Robert K.
AU  - Ware, Jeffrey B.
AU  - Young, Anthony J.
AU  - Ghodasara, Satyam
AU  - Zhao, Chao
AU  - Anderson, Hannah
AU  - Schubert, Erin
AU  - Carpenter, Erica L.
AU  - Till, Jacob
AU  - Henderson, Fraser
AU  - Pantel, Austin R.
AU  - Chen, H. Isaac
AU  - Lee, John Y.K.
AU  - Amankulor, Nduka M.
AU  - O’Rourke, Donald M.
AU  - Desai, Arati
AU  - Nasrallah, MacLean P.
AU  - Brem, Steven
TI  - Distinguishing Progression from Pseudoprogression in Glioblastoma Using <sup>18</sup>F-Fluciclovine PET
AID  - 10.2967/jnumed.122.264812
DP  - 2023 Jun 01
TA  - Journal of Nuclear Medicine
PG  - 852--858
VI  - 64
IP  - 6
4099  - http://jnm.snmjournals.org/content/64/6/852.short
4100  - http://jnm.snmjournals.org/content/64/6/852.full
SO  - J Nucl Med2023 Jun 01; 64
AB  - Accurate differentiation between tumor progression (TP) and pseudoprogression remains a critical unmet need in neurooncology. 18F-fluciclovine is a widely available synthetic amino acid PET radiotracer. In this study, we aimed to assess the value of 18F-fluciclovine PET for differentiating pseudoprogression from TP in a prospective cohort of patients with suspected radiographic recurrence of glioblastoma. Methods: We enrolled 30 glioblastoma patients with radiographic progression after first-line chemoradiotherapy for whom surgical resection was planned. The patients underwent preoperative 18F-fluciclovine PET and MRI. The relative percentages of viable tumor and therapy-related changes observed in histopathology were quantified and categorized as TP (≥50% viable tumor), mixed TP (<50% and >10% viable tumor), or pseudoprogression (≤10% viable tumor). Results: Eighteen patients had TP, 4 had mixed TP, and 8 had pseudoprogression. Patients with TP/mixed TP had a significantly higher 40- to 50-min SUVmax (6.64 + 1.88 vs. 4.11 ± 1.52, P = 0.009) than patients with pseudoprogression. A 40- to 50-min SUVmax cutoff of 4.66 provided 90% sensitivity and 83% specificity for differentiation of TP/mixed TP from pseudoprogression (area under the curve [AUC], 0.86). A maximum relative cerebral blood volume cutoff of 3.672 provided 90% sensitivity and 71% specificity for differentiation of TP/mixed TP from pseudoprogression (AUC, 0.779). Combining a 40- to 50-min SUVmax cutoff of 4.66 and a maximum relative cerebral blood volume of 3.67 on MRI provided 100% sensitivity and 80% specificity for differentiating TP/mixed TP from pseudoprogression (AUC, 0.95). Conclusion: 18F-fluciclovine PET uptake can accurately differentiate pseudoprogression from TP in glioblastoma, with even greater accuracy when combined with multiparametric MRI. Given the wide availability of 18F-fluciclovine, larger, multicenter studies are warranted to determine whether amino acid PET with 18F-fluciclovine should be used in the routine posttreatment assessment of glioblastoma.