A 45-year-old Chinese man presents with unilateral serosanguineous nasal discharge, unilateral conductive hearing loss, and a neck mass. MRI shows a mass in the fossa of Rosenmüller with skull base invasion. Biopsy shows WHO Type III histology. The EBV serological marker most specific for nasopharyngeal carcinoma in this undifferentiated type is:
- A IgM anti-EBNA (Epstein-Barr nuclear antigen)
- B IgA antibodies against VCA (viral capsid antigen) ✓
- C Heterophile antibody test
- D IgG anti-EA (early antigen)
Explanation
For undifferentiated nasopharyngeal carcinoma (NPC WHO Type III, now reclassified as non-keratinizing undifferentiated), IgA antibodies against EBV viral capsid antigen (VCA) are the most specific and sensitive serological marker used for screening (especially in endemic Chinese populations), diagnosis, and monitoring tumor recurrence. IgA VCA titers correlate with tumor burden and fall with successful treatment. Plasma EBV DNA (by PCR) is increasingly used as it is more quantitative. EBNA IgM indicates acute primary EBV infection (infectious mononucleosis). Heterophile antibodies test for infectious mononucleosis (Paul-Bunnell test). EBV latency pattern III is seen in NPC.
Reference: Dhingra Diseases of Ear, Nose and Throat, 7th ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
Written and medically reviewed by the StethoPrep medical team.