Epidemiologic evidence of superior outcomes for extramedullary plasmacytoma of the head and neck

Abstract

Objective: To compare clinicopathologic data, epidemiologic factors, and survival outcomes between extramedullary plasmacytomas of the head and neck vs other body sites.

Study design: Analysis of a national database.

Setting: Extramedullary plasmacytoma (EMP) is a rare B-cell neoplasm with a tendency to occur in the head and neck. Due to limited clinical data, few studies have conducted a thorough comparison between head and neck EMPs and those arising at other body sites.

Subjects and methods: We compared 690 EMPs of the head and neck with 495 non-head and neck EMPs, evaluating disease-specific survival (DSS) and overall survival (OS) based on tumor type, location, grade, stage, and treatment.

Results: Head and neck EMPs more often affected men (P > .001) and were typically located in the pharynx (21.5%), nasal cavity (19.3%), oral cavity (14.7%), and paranasal sinuses (13.0%). Non-head and neck EMPs were more often limited to only local disease at presentation (94.8% vs 82.1%-86.7%, P < .001). Patients with non-head and neck EMP more often received surgery alone, whereas those with head and neck EMP were more often treated with combination therapy or radiation alone (P < .001). Head and neck EMPs had a significantly higher 5-year DSS and OS than other plasmacytomas (P < .001), and they had a higher 10-year OS when treated with surgery or combination therapy than with radiation alone (P = .003).

Conclusion: Extramedullary plasmacytoma of the head and neck represents a type of tumor unique from other plasmacytomas, with distinct epidemiologic characteristics and a superior prognosis. Evidence suggests that surgically based treatments may offer improved outcomes.

Keywords: SEER database; extramedullary plasmacytoma; head and neck; solitary bone plasmacytoma.