Recurrent intraoral retromolar lipoma - a rare case report

Lipomas are slow growing, fat containing benign neoplasms which can occur anywhere in the body. They are extremely rare in the oral cavity with an incidence rate of 1-4% among all benign intraoral tumors. The intraoral site preference according to fat deposition, are buccal mucosa, tongue, floor of mouth and palate. They may grow to a large size causing difficulty in speech and mastication. Histopathological examination confirms the diagnosis, revealing a well circumscribed tumor, with lobular proliferation of sheets of mature adipocytes having clear cytoplasm and flattened, eccentric nuclei, intervened by fibrous connective tissue septae. Wide surgical excision remains the gold standard of treatment to prevent recurrence. We present a rare case of recurrent retromolar oral lipoma in which the patient reported with a chief complaint of painless swelling in the left cheek region behind the last tooth, which had progressively increased in size for the past six months to the present size. The patient gave history of similar swelling of much smaller size in childhood at the same location, which disappeared eventually. Intraoral examination revealed a round, solitary, sessile, lobulated swelling, 2x3 cm in size, which on palpation was soft, fluctuant, non-tender, non-pulsatile, mobile and the margins were slippery under the palpating finger. A provisional diagnosis of lipoma was established and a blunt surgical dissection was performed and the mass was extirpated. The histopathological picture confirmed lipoma. Neither recurrence nor any secondary swelling was observed after one year of follow up. The take home message by this case report is that a clinician should be able to correctly diagnose intraoral lipoma inspite of their rare occurrence and must confirm it histopathologically. Wide excision with routine follow up remains the gold standard of treatment for lipomas. To best of our knowledge a case of retromolar recurrent lipoma is being reported for the first time in literature.