Precision medicine in Salivary Gland Carcinoma: Insights from breast and prostate cancer

Salivary Gland Carcinomas (SGC) are a heterogeneous group of diseases with varied histologies, biology, clinical behaviors, and therapeutic approaches. The World Health Organization classifies SGCs into Low Aggression and High Aggression categories. Due to their rarity and unique biology, managing SGCs is challenging, often requiring expert histological diagnosis and treatment based on low-level evidence. Despite recent international guidelines, several critical aspects of SGC management remain unresolved, in particular regarding systemic treatment. Recent discoveries of molecular alterations, such as HER2 amplification, and AR overexpression, have provided diagnostic, prognostic, and predictive biomarkers for alternative treatments. While some targeted treatment have corresponding EMA-approved therapies, others do not. Treatment strategies are further complicated by synchronous alterations, such as AR-positive SGCs with concomitant HER2 amplification. Open questions remain on the optimal use of these drugs, whether in early-stage disease, post-surgery, or in palliative settings. Given the rarity of the disease and the consequent lack of high quality data in literature, it is of importance a cross-fertilization process from other, more common disease such as breast and prostate cancers. In the current narrative review we analyze current evidence on the targeted treatment on salivary gland carcinomas and shared features with breast and prostate cancer.