A 3-MONTH-OLD previously healthy white male infant was admitted with a lump on his lower jaw of 2 weeks' duration. During this time he had also lost 1.8 kg and had not taken solids well.
Physical examination revealed a palpable 4×6-cm hard mass on the left side of the mandible that protruded into the oral cavity. Results of physical examination were otherwise unremarkable and complete blood cell count and urinalysis results were normal. Radiographs (Figure 1) showed a rounded lesion in the central portion of the left mandible. The expanded area had exceptionally fine bone trabeculation. An intraoral biopsy specimen was taken (Figure 2) and the tumor was resected.
Two months following surgery, the tumor reappeared and grew rapidly with more extensive involvement than when the patient was first seen. A 24-hour urine collection was analyzed for vanillylmandelic acid level, which was found to be elevated. Results of a bone