e17577 Background: Salivary gland tumors (SGT) represent a rare and heterogeneous group of malignancies. No standard treatment exists in the advanced situation and the prognosis is poor. We here report characteristics and clinical outcomes of patients with SGT discussed at the Charité molecular tumor board (MTB). Methods: Patients with advanced cancer and no curative treatment option were discussed at the Charité MTB. Eligible patients underwent fresh tissue sampling and subsequent whole exome (WES) and RNA sequencing (RNA-seq) and immunohistochemical analyses (EGFR, HER2, AR as well as validation tests) or panel sequencing. Results from molecular testing were discussed at the MTB and patients were followed-up after recommendations were made. Results: 24 patients (median age 56 years, 13 male, 11 female) with advanced SGT were presented at the MTB between 2016 and 2019 (9 adenoidcystic carcinomas, 5 adenocarcinomas, 3 mucoepidermoid, 2 carcinosarcoma, 5 miscellaneous). WES/RNA sequencing was performed on tumor tissue from 16 patients. 2 patients were not included in the sequencing program and WES/RNA-Seq was ongoing for another 4 patients at the time of analysis. For another 2 patients, panel sequencing and IHC analysis, respectively was done. Results from analyses were discussed and a median of 2 recommendations, ranked by priority according to prespecified evidence levels, were made for 17 patients, each. Most commonly proposed treatment options by the MTB were FGFR inhibitors in 6 patients, mTOR or PARP inhibitors in 5 each, EGFR, HDAC inhibitors or antiandrogen therapy in 4, each. Treatments following MTB recommendations were initiated in 8 patients, 1 of which received a second recommended therapy after progression (antiandrogen therapy in 4, EGFR inhibitor in 2, a PDGFR, mTOR and PARP inhibitor in 1, each). A clinical benefit (CR = 1; Mixed Response = 1, SD = 3) was achieved in 5 patients, including a complete response in a patient with a metastatic adenocarcinoma of the parotid gland, treated with antiandrogen therapy. Conclusions: Precision oncology represents a feasible treatment strategy in patients with advanced SGT and shows early evidence of activity in a subset of patients. These results suggest further exploration of personalized therapy in these hard-to-treat tumors.
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