Human papillomavirus and WHO type I nasopharyngeal carcinoma

Abstract

Objectives: Nasopharyngeal carcinoma (NPC) is a rare cancer in the United States. An association between NPC and Epstein-Barr virus (EBV) is well-established for World Health Organization (WHO) types II and III (WHO-II/III) NPC but less well-established for WHO type I (WHO-I) NPC. Given the rise in oropharyngeal tumors positive for high-risk human papillomavirus (HPV) and the unique biology of WHO-I NPC, we examined the relationship between HPV and WHO-I NPC.

Study design: Retrospective case-comparison study.

Methods: A search of a large multidisciplinary cancer center tumor registry identified 183 patients seen from January 1999 to December 2008 with incident NPC and no prior cancer. Available paraffin-embedded tumor specimens (N = 30) were analyzed for oncogenic HPV status by in situ hybridization (ISH) and polymerase chain reaction (PCR) for HPV-16 and HPV-18; EBV status by ISH; and p16 expression by immunohistochemistry. Demographic parameters, including race and smoking, were obtained from the medical records.

Results: Among the 18 WHO-I NPC patients, 66% (N = 12) were smokers and 17% (N = 3) Asian; among the 165 WHO-II/III NPC patients, 44% (N = 73) were smokers and 24% (N = 39) Asian. Eight WHO-I NPC patients had available paraffin blocks; five of six were HPV-16-positive by PCR and four of eight were HPV-positive by ISH; only two of eight (25%) were EBV-positive. Twenty-two WHO-II/III NPC patients had available paraffin blocks; only 1 was HPV-positive by ISH, and 13 of 22 (60%) were EBV-positive.

Conclusions: These results suggest that WHO-I NPC is associated with oncogenic HPV, although larger studies are needed to verify these findings. Laryngoscope, 2010.

Figure 1

Flowchart describing patient selection. *To increase the number of patients in this group, two patients who did not meet the formal inclusion criteria were added to this category—one who presented with recurrent NPC and one who had a remote history of bladder cancer.