Material and Method
Formalin-fixed-paraffin-embedded H&E sections were made from the radical parotidectomy specimen in the usual manner. Immunostainings for AE1/3, p16, p40, S100 and Ki67 were performed using the Dako Omnis and Leica Bond-III automated IHC systems, immunostaining for CD1a used the Leica Bond-III automated IHC system.
Representative sections were subjected to CSF1 break-apart FISH test with FISH probes targeting the 5’end and 3’end of the CSF1 locus labeled orange and green respectively (Empire Genomics). Any fusion transcripts of the specimen were studied by Illumina RNA pan-cancer RNA-seq panel (Illumina), which covered the fusion transcripts of 1385 cancer-related genes including CSF1 gene. The expression of CSF1 gene was detected by RNAscope™ Probe- Hs-CSF1 (Advanced Cell Diagnostics).