Clinicopathological Spectrum of Head and Neck Mucoepidermoid Carcinoma: A Three-case Series.

Abstract

Mucoepidermoid carcinoma (MEC) is the most common malignant salivary gland neoplasm, accounting for 5%-10% of all salivary gland tumors. Although the parotid gland is most frequently affected, Mucoepidermoid carcinoma (MEC) may rarely present as an intraosseous jaw lesion, posing significant diagnostic challenges. This report presents three cases of Mucoepidermoid carcinoma (MEC) involving different intraoral sites. Each case was evaluated to highlight the diagnostic complexity and the value of histomorphological and emphasis on immunohistochemical confirmation. Case 1: A 26-year-old male with a left palatal swelling was diagnosed with intermediate-grade MEC based on histopathology and Immunohistochemistry (IHC). patient was managed by wide local excision, and he remains disease-free at 11 months. Case 2: A 24-year-old male presented with an erythematous lesion along the anterior border of the left mandibular ramus. Histopathology and Immunohistochemistry IHC (CK7, MUC-1, p40, p63, S-100 positive) confirmed low-grade MEC of minor salivary gland origin. The patient underwent wide local excision and is disease-free at 14 months. Case 3: A 48-year-old male with a right mandibular swelling and palpable level Ib lymph nodes was diagnosed with intermediate-grade intraosseous MEC (pT4N1). He underwent wide local excision with neck dissection followed by adjuvant radiotherapy (60 Gy/30 fractions) and is disease-free at 9 months. Early diagnosis and complete surgical excision remain key to achieving favorable outcomes in MEC.