Page 104 - New epidemiological and PSMA-expression based paradigms in salivary gland tumors

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Chapter 6
visualized in a boxplot. Statistics were performed using IBM SPSS Statistics for Windows, Version 21.0 (Armonk, NY, USA: IBM Corp.). The boxplot was drawn using GraphPad Prism for Windows, Version 6.02 (GraphPad Software, La Jolla, CA, USA). For this study, individual consent was not required. This was approved by the institutional Medical Research Ethics Committee, protocol number 16-790 and in accordance with the 1964 Helsinki declaration and its later amendments or comparable ethical standards.
Results
PSMA PET/CT: The thirty male patients had an average age of 68 (range 54-82 years), the mean administered activity was 173 ± 29 MBq (range 131-273 MBq). The mean time interval between tracer administration and imaging was 66 minutes (interquartile range 58-74 minutes).
PSMA-ligand uptake: All scans clearly depicted anatomical areas of salivary, seromucous, and lacrimal gland concentrations by visualizing high and homogenous uptake of PSMA-ligand (Figure 2). These areas included both major salivary glands and submucosal minor salivary and seromucous glands in the soft palate, pharynx, nasal mucosa, supraglottic larynx, and lacrimal glands. Pharyngeal tracer uptake was concentrated around a bilateral area in the dorsal wall of the nasophanrynx, measurements were presented as ‘pharyngeal wall’. See Figures 2 and 3 for an example with anatomic atlas. An annotated full version of the scan is available for review online (Supplementary Data).
The uptake of PSMA-ligand in these glands is summarized in Table I. The highest uptake was seen in the parotid and submandibular glands, with mean SUVmax 12.3 ± 3.9 (range 5.2 – 22.9) and 11.7 ± 3.5 (6.0 – 22.2), respectively. For reference, the mean maximal uptake values in the liver and kidneys were 3.7 ± 0.8 (2.4 – 5.0) and 28.8 ± 7.6 (16.9 – 44.5), respectively. The intra-individual differences in SUVmax of the paired glands varied per location. Details are listed in Table II and Figure 4.