Plasmacytoma of the Temporal Bone, a Great Imitator: Report of Seven Cases and Comprehensive Review of the Literature.

OBJECTIVES

To describe the clinical presentation, radiological features, and outcome of patients with plasmacytoma of the temporal bone.

METHODS

Multicenter retrospective case series of all patients diagnosed with plasmacytoma of the temporal bone between 1990 and 2015. Comprehensive literature review of all previously published cases.

RESULTS

A total of seven patients (average age, 57.3 yr; 57% women) met inclusion criteria. Three (43%) had a known history of multiple myeloma (MM). The most common symptoms at presentation included otalgia, headache, and dizziness (43%, each). Five (71%) presented with a vascular appearing middle ear mass visible on otoscopy. Four of these patients did not have an established history of MM and were referred with presumptive diagnoses of paraganglioma or endolymphatic sac tumor (ELST). The average maximum tumor diameter was 3.7 cm (median, 3.5 cm; range, 0.9-6.6 cm) and the most commonly involved temporal bone subsites were the middle ear and mastoid (71% each). MM was ultimately diagnosed in six cases (86%). In addition to the new cases presented herein, 18 previously published reports were analyzed. In the 25 aggregate cases, 44% of cases were associated with MM, and the mastoid (72%) and middle ear (53%) were the most commonly involved temporal bone subsites.

CONCLUSION

Plasmacytoma of the temporal bone is rare, and the clinical presentation can closely mimic that of other primary temporal bone tumors. In patients with an established history of MM, it is imperative to have a high index of suspicion for temporal bone plasmacytoma, even when radiological features suggest an alternate diagnosis.