Nasopharyngeal carcinoma (NPC) has a strong association with EBV. Which EBV latency protein is detectable in serum and is used for NPC screening and monitoring response to treatment?
- A IgA antibody to EBV viral capsid antigen (VCA-IgA) — elevated in WHO types II and III NPC; serial monitoring after treatment predicts relapse ✓
- B EBV nuclear antigen 1 (EBNA-1) IgG alone
- C LMP-2A (Latent Membrane Protein 2A) directly measured in serum
- D EBV early antigen IgM for acute primary infection
Explanation
EBV-associated NPC (WHO types II and III — non-keratinizing undifferentiated and non-keratinizing differentiated) shows elevated serum VCA-IgA (IgA directed against the viral capsid antigen) and EBV EA-IgA in up to 96% of cases. VCA-IgA is used for: (1) population screening (particularly in Cantonese Chinese), (2) confirming diagnosis in early NPC, and (3) monitoring after treatment where falling titers indicate response and rising titers suggest relapse. Additionally, plasma cell-free EBV DNA (EBVDNA) is now the gold standard for staging and monitoring NPC per current international guidelines.
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.