ABSTRACT
Cystadenoma is an uncommon benign epithelial neoplasm. Cystadenoma usually occurs on the palatal and buccal mucosa, but is less commonly found in the retromolar regions.A 43-year-old male patient noticed a swelling on his gingiva distal to the right mandibular second molar. Physical examination showed a diffuse poorly circumscribed swelling extending from the lingual gingiva distal to the right mandibular second molar to the floor of the mouth and pharynx. The tumor size was 20 x 27 mm. The surface mucosa was purply-blue in parts. About 4 ml of pale yellow serous fluid was aspirated. The tumor was surrounded by a capsule and was excised successfully above the periosteum, incorporating a 2 mm safety margin including the surface mucosa. The tumor consisted of a fibrous capsule with multiple cystic cavities of various sizes. The cysts were lined by a layer of columnar epithelium, with intracystic papillary proliferation in some areas. No cytologic atypia or invasion of the surrounding tissues were observed.There is no evidence of recurrence ten years after excision, suggesting that complete excision is sufficient treatment in such cases.