A casual role for Human Papilloma virus-16 for the Head and Neck Cancers word wide-and role of HPV vaccine altering the carriage rate of oropharyngeal HPV16?

Dear Editor

Infection with Human Papilloma Virus (HPV) 16 and 18 mostly is well established for development of cervical cancers in pre and post menopausal women through out the world. Professor H. Zur Housen was awarded the Nobel Prize for medicine and physiology for establishing role of HPV in development of cancer in 2008 instead of HSV2. But a pathogenic role for this HPV in non ano- genital cancer has yet been unclear till now. Tobacco and alcohol is considered today as important etiological factor for Head and Neck Squamous cell cancers(HNSCC). Epidemiological and laboratory evidences howevver now suggest this conclusion that in addition to tobacco and alcohol, HPV may be also the causative agent for the head and neck SCC. In our Institute at IPGME&R, Kolkata-20, West Bengal, India, from Pathology department the major bulk of cancer are diagnosed in the male population in any year is HNSCC and more then 95% of these sufferers gives however history of either smoking cigarette or local made Bidi or chewing Pan Parag products for long periods. These people are usually older and middle aged male. What about those young people dignosed with HNSCC? As with cervical cancer HNSCC is today a world wide public health problem with more then 9-10 lacks population per year are diagnosed by the Histopathologists having HNSCC. High risk HPV like HPV16 or HPV18 is probably not necessary for development of HNSCC. In our laboratory, we carried a work for 2 years on Role of HPV 16 and HNSCC mostly in younger people particularly and found HPV type 16 DNA is present in primary[poorly differentiated] and in metastatic cell nucleus in high copy numbers frequently integrated and transcriptionaly active by ISH technique. We are not sure whether these findings is casual association of HPV16 with HNSCC or etiology. Researches over past several years had also shown a string and consistent association between high risk HPV and distinct subset of HNSCC . However in our study these HPV associated HNSCC are characterized clinically by their location within the laryngeal and palatal tonsil of oropharynx. Their poorly differentiated histopatholgy and their frequent occurrence in nonsmoking and young patients then in HNSCC not associated with HPV. The proportion of HNSCC that is associated with HPV may be greater in a nonsmoker. HPV positive cancer may also occur in smokers. However it is unclear whether elevated risk of HNSCC for contamination of HPV infection and tobacco addiction is synergistic or additive with HPV? Thus screening for HPV in oral cavity and development of oral PAP smear might lead to early diagnosis and treatment for HNSCC. The prevalence of oral HPV infection presently a pre-requisite for HPV associated HNSCC was around 7% in centers without cancer in the IARC study [1] Another possibility for prevention of HPV associated HNSCC lies in HPV vaccine as we consider. Systemic Immunization with a protective HPV16 vaccine will be highly effective no doubt in preventing persistence HPV 16 in female genital tract. It is however not known to us whether such a vaccine will also alter the carriage rate of oropharyngial HPV16 and HNSCC.

Professor Pranab kumar Bhattacharya MD(cal), FIC path(Ind.) , Professor of Pathology, In charge of Histopathology Unit, in charge Blood Bank &VCCTC, Cytogenetics. Institute of Post Graduate Medical Education & Research, 244a AJC Bose Road, Kolkta-20, West Bengal, India; **Mr. Ritwik Bhattacharya, B.Com(cal); ***Mr. Rupak Bhattacharya BSc(Cal)MSc(JU) of 7/51 purbapalli, Sodepur Dist 24 parganas(North) Kol- 110, West Bengal, India; ****Mrs Dahlia Mukherjee BA(hons) Swamiji Road, Habra N-24 parganas, W.B, India, *****Miss upasana Bhattacharya of Mahamyatala, Garia kol-86,Daughter of Prof. Bhattacharya**** Dr Debasis Bhattacharya Ms(cal) FRCS(eng). Associate Professor, dept. of Surgery IPGME&R, Dr. Tarun Mandal MBBS(cal) , Dr. Ananya Pal MD(PGT) Pathology Dept. Of Pathology Institute of Post Graduate Medical Education & Research, 244a AJC Bose Road, Kolkta-20, West Bengal, India

Reference
1. Herrero R, Castellasaguex, Pawlita M etal “ Human Paplloma Virus and Oral Cancer, The international gency for Research on Cancer-a multicenter study J. Natl .cancer Institute 2003:95:1272-83