Clinical Applications of 68Ga-PSMA PET/CT on Residual Disease Assessment of Juvenile Nasopharyngeal Angiofibroma (JNA)

Abstract

We present a case of a 16-year-old boy who underwent 68 Ga-PSMA PET/CT for residual disease assessment of juvenile nasal angiofibroma. Positive uptake was noted in residual tumor on PET/CT imaging. However, there was no abnormal uptake in surrounding scar tissues as compared with contrast-enhanced magnetic resonance imaging. These findings were confirmed by biopsy from the scar tissue on posterior ethmoids. 68 Ga-PSMA PET/CT may be a potentially valuable tool especially in distinguishing recurrences from surgical site reparative tissue and in planning and delivering stereotactic radiotherapy.

68Ga DOTANOC PET/CT Scan in Primary Juvenile Nasopharyngeal Angiofibroma ‐ A Pilot Study

“…We have proved earlier with PSMA PET/CT that, the additional value of functional PET/CT in the clinical management of JNA patients with ambivalent diagnostic situations such as the detection of recurrence 25–28 . Anatomical/structural CEMRI and/or CECT are often incapable of precisely demarcating residual/recurrent disease from post‐surgical healing tissues while the functional scan targeting the tumor receptors aids this differentiation with ease.…”

Negative 68Ga–Prostate-Specific Membrane Antigen PET/CT Scan on a Recurrent Juvenile Nasopharyngeal Angiofibroma

“…2 Over the last 2 years, 68 Ga-PSMA PET/CT had evolved as the criterion standard for detection of residual or recurrent JNA as it avidly binds PSMA in the tumor-related neovasculature, not the postoperative scar tissue. [3][4][5][6][7] Recently, Thakar et al 5 had validated the PARIS (Postoperative Angiofibroma Radionuclide Imaging Study) protocol using PSMA PET/CT in the accurate assessment of residual or recurrent JNA. They had observed 100% sensitivity, specificity, positive predictive value, and negative predictive value of PSMA PET/CT in the assessment of recurrent or residual JNA.…”

“…Because postoperative scar tissue also enhances with contrast, CEMRI may not be able to differentiate residual or recurrent tumor from fibrotic tissue, leading to false-positive results 2 . Over the last 2 years, 68 Ga-PSMA PET/CT had evolved as the criterion standard for detection of residual or recurrent JNA as it avidly binds PSMA in the tumor-related neovasculature, not the postoperative scar tissue 3–7 . Recently, Thakar et al 5 had validated the PARIS (Postoperative Angiofibroma Radionuclide Imaging Study) protocol using PSMA PET/CT in the accurate assessment of residual or recurrent JNA.…”

Fusion 68Ga-DOTANOC PET/MRI in Primary Juvenile Nasal Angiofibroma

“…Fusion PET/MRI combines the MRI features such as soft tissue delineation, diffusion-weighted and dynamic contrast-enhanced imaging, fMRI, specialized sequences, and MR spectroscopy with the quantitative physiologic information that is provided by PET proving to be a better pretreatment imaging modality compared with either alone. However, hybrid PET/MRI scanners are not widely available and have a high cost 11 . Hence, a software-based fusion technique can be used for easy early recurrence identification, better delineation from postoperative scar tissue, for planning the exact target volumes for stereotactic radiotherapy of inoperable, residual, and recurrent JNAs in the future 5,11 …”

“…However, hybrid PET/MRI scanners are not widely available and have a high cost. 11 Hence, a software-based fusion technique can be used for easy early recurrence identification, better delineation from postoperative scar tissue, for planning the exact target volumes for stereotactic radiotherapy of inoperable, residual, and recurrent JNAs in the future. 5,11…”