Diagnostic Information

History of Present Illness The patient had become aware of the lesion in the past two weeks as the mass was causing problems with his denture fitting properly.  The mass was mildly tender to palpation but not spontaneously painful.  The patient did not recall any recent trauma and said that he felt “okay” otherwise. Medical History The patient reported a history of type II diabetes which was controlled with glipizide.  The remainder of his medical history was unremarkable and review revealed no other abnormalities. Clinical and Radiographic Findings Clinical exam revealed a 4.0 X 2.5 cm raised, partially fluctuant, multinodular mass of the right tuberosity (Figure 1).  The lesion was bluish in color and compressible to palpation.  The remainder of the oral cavity was within normal limits.  A panoramic radiograph failed to reveal any obvious bony changes.

Figure 1.Raised, bluish mass of the maxillary right tuberosity.

Incisional Biopsy Findings On microscopic examination, the lamina propria was infiltrated by a solid mass of round mononuclear cells exhibiting mild pleomorphism (Figures 2 and 3).  These cells contained enlarged, hyperchromatic nuclei with prominent nucleoli (Figure 4).  Additional immunohistochemical stains revealed positive staining for leukocyte common antigen (LCA) and CD20.  Staining for the keratin marker (AE1/AE3) was negative.

Figure 2.Low power photomicrograph showing a solid, monotonous sea of blue, round mononuclear cells.

Figure 3. Medium power photomicrograph showing mild nuclear pleomorphism.

Figure 4. Close inspection at high power revealing enlarged, hyperchromatic nuclei with prominent nucleoli.