Comprehensive diagnosis and treatment of ductal carcinoma of the submandibular gland: case report and literature review

Salivary duct carcinoma (SDC) is a rare malignant tumor of the salivary gland and is most commonly found in the parotid gland, followed by the submandibular gland. Due to its rarity, there is no consensus on its treatment. Surgical resection is currently the only curative treatment. Considering its high degree of malignancy, extensive tumor resection and postoperative adjuvant radiotherapy are recommended. We report a rare case of SDC of the submandibular gland. A 62-year-old man presented to our hospital with complaints of swelling in the right sub -maxillary area for 4 months, rapidly growing, with pain for 10 days. After admission, fine needle aspiration (FNA) revealed right submandibular gland ductal carcinoma. Considering its aggressiveness, large size, and invasion of parapharyngeal and oral floor soft tissues, the patient received two cycles of neoadjuvant chemotherapy followed by extended surgical resection. Postoperatively, the patient received four cycles of concurrent chemoradiotherapy, followed by afatinib targeted therapy. No recurrence or metastasis was observed in a 45-month follow-up. Thus we present a comprehensive treatment for salivary duct carcinoma combining neoadjuvant chemotherapy with surgery, postoperative concurrent radiotherapy, and chemotherapy followed by afatinib targeted therapy.