EBV-Positive Plasmacytomas Involving a Nasopharyngeal Angiofibroma in an Adolescent

Area of Science:

• Oncology
• Pathology
• Pediatric Medicine

Background:

• Collision tumors involving extramedullary plasmacytoma and nasopharyngeal angiofibroma are exceptionally rare, particularly in pediatric cases.
• Nasopharyngeal angiofibroma is a benign vascular tumor typically affecting adolescent males, while extramedullary plasmacytoma arises from plasma cells.

Observation:

• A pediatric patient presented with a collision tumor exhibiting typical nasopharyngeal angiofibroma morphology and a dense plasmacytic infiltrate.
• The neoplastic plasma cells displayed varied morphologies, tested positive for Epstein-Barr virus encoded RNA (EBER), and showed an aberrant immunophenotype.

Findings:

• Fluorescence in situ hybridization revealed specific chromosomal gains (1q21.3, 3q27, 11q22.3) but no rearrangements of ALK or MYC.
• Next-generation sequencing did not identify any pathogenic mutations, underscoring the unique genetic profile of this tumor.

Implications:

• Distinguishing this plasmacytoma with EBER positivity and plasmablastic morphology from plasmablastic lymphoma is critical due to differing prognoses and management strategies.
• This case emphasizes the necessity of comprehensive pathological evaluation for synchronous neoplastic processes to ensure accurate diagnosis and appropriate patient care.