3475
CONTEXT : Nasopharyngeal carcinoma ( NPC ) , common in southern China and North Africa , has a complex etiology involving interplay between viral , environmental , and hereditary factors and is almost constantly associated with the Epstein - Barr virus .
 Nasopharyngeal carcinoma, NPC
Please list all entity words in the text that fit the category. Output format is "word1, word2". 
Option: Anatomy 
Text: {0} 
Answer:
 Nasopharyngeal carcinoma, NPC