A challenging case of field cancerization

Abstract

A challenging case of field cancerization K Bektas¸-Kayhan1 , G Karagoz*1 , CD Ozbek1 , M Altun2 , DE Peterson3 , M Unur1 1 Department of Oral Surgery, Faculty of Dentistry, Istanbul University, Istanbul, Turkey, 2 Department of Radiation Oncology, Institude of Oncology, Istanbul University, Istanbul, Turkey, 3 Department of Oral Health and Diagnostic Sciences, School of Dental Medicine, University of Connecticut Health Center, Farmington, CT, USA Introduction: The process of formation of oral cancer results from multiple sites of premalignant change in the oral cavity (field cancerization). Field cancerization is a proposed mechanism for the development of independent multiple premalignant lesions and tumors in the head and neck suggesting that the upper aerodigestive tract epithelium undergoes simultaneous genetic changes due to common carcinogenic exposures. The probability of developing an SPT in the patients who have had head and neck squamous cell cancer is around 20% and for each year the rate is 4–6%. Case: A 50-year-old man with squamous cell carcinoma of tongue T3N1M0 who had previously chemo-radiotherapy presented with diffuse oral mucositis-like lesions on edentulous alveolar crest that had been evolving since the cession of radiotherapy. After multiple biopsies showing a range of chronic ulceration, dysplasia, HPV positivity after 20 month, widespread lesions covering the tongue, buccal mucosa, vestibular sulcus and lips which developed into squamous cell carcinoma. Conclusion: Field cancerization is a confusing contradiction to clinicians and surgeons alike. Furthermore, it significantly affects the morbidity and mortality of oral cancer patients. The solution to this problem seems to be remote; lifelong surveillance for high-risk patients at regular intervals still remains the mainstay in the anticipation of more precise targeted treatments comprising of surgery, radiotherapy, chemotherapy, and perhaps gene therapy that can be developed in patients with evidence of field change. There is considerable debate as to the clonality of the patch of affected mucosa/ field lesion and development of second primary tumors (SPT) or multiple primary tumors (MPT). Relevance: Given that the survival rate of patients with multiple primary tumors is worse than those with only one primary tumor, preventing the second primary tumor is crucial well-being of the patient.