Th 83262

Case Study

Feb. 1, 2002

A 68-year-old female visited a general dentist for an examination and denture reline. During the intraoral exam, a yellow, dome-shaped mass was noted on the buccal mucosa.

History
The patient was unaware of the dome-shaped lesion on the inside of the cheek. The lesion was described as painless and had no history of bleeding. When questioned about trauma, the patient did not recall biting her cheek in the affected area.

The patient appeared to be in a general good state of health and denied any recent history of serious illness. The medical history revealed a history of hypertension and no other significant findings. At the time of the dental appointment, the patient was taking medication to control the hypertension.

Examination
The patient's blood pressure, pulse rate, and temperature were all found to be within normal limits. No enlarged lymph nodes in the head and neck region were detected upon palpation. Oral examination revealed one yellow, dome-shaped lesion on the anterior buccal mucosa (see photo). Palpation of the lesion revealed a well-circumscribed, soft, and doughy mass. Further examination of the oral tissues revealed no other lesions present.

Click here to enlarge image

Clinical diagnosis
Based on the clinical information presented, which of the following is the most likely clinical diagnosis?

  • granular cell tumor
  • epidermoid cyst
  • mucocele
  • irritation fibroma
  • lipoma

Diagnosis

  • lipoma

Discussion
The lipoma is a benign tumor composed of mature fat cells. The lipoma is primarily seen in the subcutaneous tissues of the neck and trunk; it is uncommon to see the lipoma in the oral cavity. The term lipoma literally means tumor of fat (lipo- meaning fat, -oma meaning tumor).

The cause of the lipoma is unknown. The lipoma is not a reactive lesion and does not result from irritation or trauma. There is no significant medical condition associated with the occurrence of the lipoma.

Clinical features
The lipoma has been reported to occur in all age groups, but is most frequently identified in individuals over the age of 40. There is no sex or race predilection. The lipoma is most often found on the buccal mucosa and in the muccobuccal fold region; the tongue, floor of the mouth and lip also may be involved.

The lipoma is a slow-growing mass that usually occurs as a solitary lesion. Lipomas may appear sessile or pedunculated. Size may range from less than 1 centimeter to greater than 5 centimeters in diameter. The shape and contour of the lipoma may vary from a well-circumscribed, round nodule to an ill-defined and lobulated mass.

The typical lipoma is a superficial lesion that is found close to the mucosal surface. The color will depend on the thickness of the overlying mucosa. If the overlying mucosa is thin, the yellow color of the underlying fat shows through and gives this tumor its characteristic yellow or yellowish-white color. The surface of the lipoma is smooth and nonulcerated, unless the lesion is traumatized. When palpated, the lipoma is soft and doughy. Large and diffuse lesions may feel fluctuant and be confused with a cyst.

The lesion is asymptomatic; no pain is associated with the lipoma.

Diagnosis and treatment
A biopsy and histologic examination is necessary to establish the diagnosis of a lipoma; the diagnosis cannot be established on a clinical basis. When examined histologically, the lipoma appears as a circumscribed mass of mature adipose (fat) cells surrounded by a connective tissue capsule. Interspersed among the fat cells are varying numbers of fibrous connective tissue septae that divide the lesion into lobules.

The recommended treatment for the lipoma is surgical excision. The lipoma does not have malignant potential and should not recur following removal.

Joen Iannucci Haring, DDS, MS, is an associate professor of clinical dentistry, Section of Primary Care, The Ohio State University College of Dentistry.