Accuracy of Narrow-Band Imaging-Guided Histopathology and Ki-67 Index in Head and Neck Carcinoma

Abstract

ABSTRACT As per Globocan 2012, every year the incidence of head and neck cancer is 683235/1000000 with a mortality of around 375665/1000000 thus being the sixth cause of cancer death throughout the world. Head and neck cancer includes cancer of the nasopharynx, oropharynx, hypopharynx, larynx, and oral cavity. Early diagnosis of head and neck cancer is very challenging, hence detecting mucosal lesions at an early stage decreases mortality thereby improving overall survival, disease-free survival, and quality of life. Out of different diagnostic modalities, narrow-band imaging (NBI) combined with endoscopic techniques can provide a promising diagnostic tool in detecting early lesions of head and neck cancer. Numerous studies have shown that Ki-67 is a good prognostic marker in oral cancers. Our study aims to evaluate the diagnostic accuracy of NBI and combine the Ki-67 index to diagnose head and neck cancer. Materials and Methods: All patients were first examined under white light and then under NBI endoscopy, and a biopsy was obtained from suspected lesions and sent for histopathological examination (HPE) and Ki-67 index. Results: Eighty patients were examined out of which, 68 patients having lesions in the oral cavity, oropharynx, larynx, and hypopharynx were examined. The rate of detecting cancerous lesion by white light and NBI were respectively 92% and 100% for oral cavity lesions, 69% and 100% for oropharyngeal lesions, 38% and 100% for hypopharyngeal lesions, and 37% and 100% for laryngeal carcinoma. However, we have found no significant difference in detecting T2-T4 tumors. Hence, we concluded that NBI mode can be a significantly better diagnostic tool than white light mode in detecting early mucosal cancer in head and neck cancer. Conclusion: We have concluded that NBI combined with Ki-67 estimation is a very promising tool that helps in the early diagnosis of mucosal lesions in head and and neck cancer.