Source: Journal of Clinical Oncology
To the Editor:
In their article, Chaturvedi et al1 document the rise in human papillomavirus (HPV) –associated cancers as a proportion of squamous cell carcinomas of the oropharynx over the last 25 years. The contemporary figures are mirrored by two recent British studies2,3 demonstrating that the majority of oropharyngeal cancers are now HPV related.
In the accompanying editorial,4 Mroz et al rightly highlight the importance of evaluating HPV vaccination for both men and women in the light of these data and lament the lack of significant improvement in the outcomes for non–HPV-associated head and neck cancers. However, they also suggest that the benefit of targeting epidermal growth factor receptor (EGFR) through concurrent cetuximab may be confined to HPV-associated tumors. Although EGFR expression per se does not correlate closely with response to cetuximab, there is increasing evidence of an inverse correlation between p16INK4A expression (as a marker of HPV association) and EGFR expression shown by immunohistochemistry.5,6 Though suppressed by viral oncogenes, HPV-associated tumors retain wild-type P53,7 and patients with this tumor type have demonstrated excellent survival with existing protocols such as concurrent chemoradiotherapy or surgery with postoperative radiotherapy. Conversely, non-HPV tumors, harboring a range of mutations,8 may respond less well to DNA-damaging agents, but patients with these tumors might benefit from the addition of concurrent EGFR blockade to radiotherapy. Data from the recent SPECTRUM (Study of Panitumumab Efficacy in Patients With Recurrent and/or Metastatic Head and Neck Cancer) study of adding another EGFR-targeting monoclonal antibody, panitumumab,9 suggest that in the metastatic setting at least, only patients with HPV-negative tumors benefit from a combination of palliative chemotherapy and an anti-EGFR strategy. If confirmed in sample sets containing non-HPV tumors treated with EGFR-targeting agents in combination with radiotherapy, this could open the door to the improvements urgently needed in HPV-negative oropharyngeal cancers, where an older demographic and greater burden of comorbidities make the uncomplicated and complete delivery of concurrent chemoradiotherapy challenging.
AUTHORS’ DISCLOSURES OF POTENTIAL CONFLICTS OF INTEREST
Although all authors completed the disclosure declaration, the following author(s) indicated a financial or other interest that is relevant to the subject matter under consideration in this article. Certain relationships marked with a “U” are those for which no compensation was received; those relationships marked with a “C” were compensated. For a detailed description of the disclosure categories, or for more information about ASCO’s conflict of interest policy, please refer to the Author Disclosure Declaration and the Disclosures of Potential Conflicts of Interest section in Information for Contributors.
This news story was resourced by the Oral Cancer Foundation, and vetted for appropriateness and accuracy.