Feasibility of a targeted protein panel for personalized treatment in advanced adenoid cystic carcinoma: A proof‑of‑concept study

Treatment options for advanced recurrent or metastatic (R/M) adenoid cystic carcinoma (ACC) remain limited, with few effective molecular-based therapies.Advances in targeted protein panels provide an approach for identifying potentially targetable protein expression patterns and supporting individualized treatment considerations; however, their feasibility and decision-support potential in R/M ACC remain poorly defined.The present proof-of-concept study evaluated the feasibility and decision-support potential of a predefined immunohistochemistry-based 11-protein panel in heavily pretreated patients with R/M ACC.Among 10 patients with advanced R/M ACC, seven underwent tumor profiling using the panel.Potentially actionable targets, including epidermal growth factor receptor (EGFR), MET proto-oncogene, receptor tyrosine kinase, KIT proto-oncogene, receptor tyrosine kinase, and platelet-derived growth factor receptor, were identified in 86% of profiled cases.Based on these findings, panel-based therapy recommendations were issued for the majority of patients.In one illustrative case, EGFR-directed therapy with gefitinib was associated with ~3 years of disease stability.In conclusion, these findings support the feasibility of a pragmatic immunohistochemistry-based approach to inform treatment discussions in advanced R/M ACC.However, the clinical relevance of these findings requires further validation in larger prospective cohorts.