Frequency of FGFR1 amplification is similar in SqCC with and without lymph node metastases, but status in metastatic sites may be discordant from the primary in a small subset of cases, which may affect the decision to perform testing of metastatic SqCCs.
One hundred twelve primary tumors (including squamous cell carcinoma [SCC], carcinoma associated with an inverted papilloma, sinonasal undifferentiated carcinoma [SNUC], adenocarcinoma, adenoid cystic carcinoma [ACC], esthesioneuroblastoma, and 9 corresponding lymph node metastases) were assessed by fluorescence in situ hybridization (FISH) for FGFR1 copy number status.
Tissue microarrays containing 135 primary lung SqCCs and 58 matching lymph node metastases were tested by interphase fluorescence in situ hybridization for DNA copy number (CN) abnormalities at the 8p12 region including FGFR1.
Resembling a potential therapeutic drug target, fibroblast growth factor receptor 1 (FGFR1) amplification and expression was assessed in 515 human colorectal cancer (CRC) tissue samples, lymph node metastases and CRC cell lines.
In metastatic tumors, 18% (seven of 39) of the lymph node metastases displayed FGFR1 amplification with an exact correlation of FGFR1 amplification status between tumor and metastatic tissue.