Metastatic Laryngeal Minor Salivary Gland Carcinoma to the Liver: Successful Treatment with Anti-EGFR-Based Combination Therapy - A Case Report and Literature Review

Laryngeal minor salivary gland carcinoma is a rare malignancy, accounting for less than 1% of laryngeal cancers. We present a case of a 43-year-old male with a history of surgically resected laryngeal ductal carcinoma who developed liver metastases. Initial pathology from the liver lesion was inconclusive, leading to a misdiagnosis of intrahepatic cholangiocarcinoma. After progression on first-line chemotherapy and immunotherapy, the diagnosis was revised to metastatic laryngeal minor salivary gland carcinoma, supported by positive EGFR expression. Second-line treatment with the anti-EGFR agent cetuximab, combined with immunotherapy and chemotherapy (sindilizumab, albumin-bound paclitaxel, and S-1), resulted in a sustained partial response. This case highlights the diagnostic challenges of this rare tumor and suggests the potential efficacy of anti-EGFR therapy in EGFR-expressing metastatic laryngeal salivary gland carcinoma. Given the rarity and aggressive nature of primary laryngeal salivary duct carcinoma, it remains a significant challenge for both diagnosis and treatment. The current case underscores the difficulty in identifying the primary tumor site, especially when metastasis occurs. Additionally, the effectiveness of anti-EGFR therapy in EGFR-expressing tumors offers a promising treatment avenue. Further research is essential to establish standardized treatment protocols, identify predictive biomarkers, and optimize combination strategies for this uncommon malignancy.