Submandibular Gland Invasion From a Metastatic Lymph Node in Patients With Buccal Mucosal Squamous Cell Carcinoma: A Case Report.

This report presents a rare case of direct invasion from a metastatic submandibular lymph node (SMLN) to submandibular gland (SMG) in a resected specimen of neck dissection (ND) of buccal mucosal squamous cell carcinoma (SCC). The patient was an 82-year-old woman with a clinical diagnosis of the left buccal mucosal SCC (cT4bN2bM0, Stage IVB). The tracheostomy, modified radical neck dissection, buccal mucosal cancer resection including maxillary partial resection, mandibular segmentectomy, and reconstructive surgery with a plate and a free rectus abdominis flap were performed. Pathologically, the infiltrating SCC was observed in the SMG continuous with SMLN metastasis (pT4bN3bM0). No adjuvant therapy was performed for old age and oral intake dysfunction. Contrast CT detected the multiple lung and left scapula metastases at postoperative 5 months, which made the policy of best supportive care. Finally, she died 9 months after the surgery from distant metastases. SMG involvement from direct invasion from a metastatic SMLN is relatively rare. In our case, although the patient died from distant metastases, locoregional control was achieved through curative resection of the primary tumor and ND performed as one block with reconstructive surgery.