A Rare Case of Primary Squamous Cell Carcinoma of the Submandibular Salivary Gland: Brief Overview of Diagnostic Ambiguity and Treatment Challenges.

Primary squamous cell carcinoma of the submandibular salivary gland is a rarity with obscure etiology and atypical presentation. The features include a progressively enlarging swelling in the lateral neck just below the mandible, which is rarely tender. Surgery is the mainstay of the treatment, and the role of adjuvant therapies is not defined. Precise diagnosis demands a step-by-step systematic approach to exclude the presence of any index tumor. A 65-year-old countryside male presented to our institute with a complaint of submandibular swelling of the right side. After the exclusion of the primary, he was treated surgically with safe margins, ipsilateral comprehensive neck dissection, and adjuvant therapy. One month post-chemoradiotherapy, the patient developed a second primary in the contralateral submandibular region with lung metastasis and succumbed to death due to malignant cachexia. The stage of the disease at presentation, bone and skin involvement, lymphovascular invasion, poorer differentiation, and distant metastasis are associated with dismal outcomes. An early diagnosis and comprehensive surgical management with adjuvant chemoradiotherapy must be accomplished.