Polymorphous adenocarcinoma of minor salivary gland: Case presentation and literature review

Introduction and importance: Polymorphous low-grade adenocarcinoma (PLGA) is a rare neoplasm arising from minor salivary glands, representing approximately 3 % of head and neck tumors. The clinical presentation of PLGA is defined as a painless, slow-growing tumor, mostly occurring in the palate. We report a case of PLGA with a rare presentation. Case presentation: A 76-year-old male, known case of hepatitis B, diabetes, and hypertension, presented to the emergency department complaining of spitting blood and dysphagia. Imaging showed a heterogeneous enlarged left tonsil with hyperemia of the mucosa, and air foci. Biopsy with excisional biopsy confirmed the diagnosis of PLGA. The patient underwent completion tonsillectomy and selective neck dissection which yielded tonsillar tissue with underlying PLGA, and reactive lymph nodes with no malignant tissue respectively, margins were negative for malignancy. Clinical discussion: Polymorphous low-grade adenocarcinoma is a rare lesion with clinical behavior resembling that of a benign neoplasm. Predominantly occurring in the oral cavity, especially on the hard palate, buccal mucosa, and retromolar region, with fewer cases in the upper lip. Occurrence in the nasopharynx and oropharynx is rare. PLGA presents as painless slow-growing masses, typically in females aged 50-60. Local excision with careful margin evaluation is the preferred treatment, with good prognosis compared to other carcinomas. Conclusion: PLGA is rare, with limited reported case from around the world. It is mostly seen in adults between their fifth and sixth decades with female predominance. PLGA is diagnosed using imaging, immunohistochemistry. Owing to the limited cases there is no standard approach to treating PLGA. However, most cases are managed with local excision and showed an excellent response in terms of tumor nonrecurrence.