Solitary Plasmacytoma of the Head and Neck: Case Series and Review of the Literature

Introduction: Solitary plasmacytoma (SP) is a rare neoplasm characterized by localized proliferation of monoclonal plasma cells and is classified as solitary bone (SBP) or solitary extramedullary (SMP) plasmacytoma. Both entities represent a localized infiltration of the neoplasm with no systemic disease and no or minimal bone marrow plasmacytosis.

Plasma cell dyscrasias present within a spectrum of disease. SBP and SMP each make up 3% of all plasma cell neoplasms, with SMPs comprising less than 1% of head and neck tumors.

Plasmacytoma with anaplastic features is an exceedingly rare histopathological subcategory in which a 2021 review found only 5 previously reported cases, in which we will detail the sixth.

Solitary plasmacytomas of the skull base is also extremely rare and clinical presentation can mimic other disease processes. Those involving the temporal bone are also unusual, with only 28 previously reported in the English literature.

Case Presentations: A 78-year-old male presented with a 3-month history of epistaxis and progressive obstruction of the right nasal passage. CT imaging revealed a mass in the right nasal cavity with destruction to the maxillary sinus. An excisional biopsy was performed revealing anaplastic plasmacytoma.

A 64-year-old male with a past medical history significant for prostate cancer presented with a 2-month history of left ear pain and progressive non-tender temporal swelling. A PET/CT revealed a highly avid, destructive, and lytic left temporal mass with no other evidence of distant disease. A left temporal craniectomy and infratemporal fossa dissection revealed plasma cell dyscrasia with monoclonal lambda in-situ hybridization.

Discussion: Extramedullary plasmacytoma is a rare entity. They often present with vague or slowly progressive symptoms. Although plasmacytomas are uncommon tumors of the head and neck, otolaryngologists may play an important role in prompt diagnosis and management.

Conclusion: Solitary plasmacytoma is a rare disease process. We present a case series of two plasma cell neoplasms.

No conflict of interest has been declared by the author(s).

Publication History

Article published online:
01 February 2023