Using Narrow-band Imaging (NBI) Technique to Detect Post-radiotherapy Mucosal Residual Nasopharyngeal Carcinoma (NPC)
Phase: NA
Conditions: Nasopharyngeal Carcinoma
Sponsor: Pamela Youde Nethersole Eastern Hospital

Protocol_-_NBI_for_residual_NPC ver 3 
 
Protocol 
Title: 
- 
Using narrow-band imaging (NBI) technique to detect post-radiotherapy mucosal residual  
nasopharyngeal carcinoma (NPC) 
Investigator 
- 
Dr. Wong Kai Chuen, Fergus
１ 
- 
Dr. Yeung Yat Bong
１ 
- 
Dr. Chang Tien Yee, Amy
２ 
- 
Dr. Tong Fu Man
１ 
1: Department of Ear, Nose and Throat, Pamela Youde Nethersole Eastern Hospital 
2: Department of Oncology, Pamela Youde Nethersole Eastern Hospital 
Background 
- 
NPC has a uniquely high prevalence in Southern China. According to the Hong Kong Cancer 
Registry in 2012, NPC was the sixth commonest cancer in men and thirteenth in women. It 
accounted for 2.9% of all new cancer cases. In 2012, there were 819 new cases of NPC.  
- 
NPC is highly radiosensitive. Radiotherapy and chemotherapy are the mainstay of treatment. 
Despite the chemo-irradiation, disease control failure still occurred in NPC patients presenting as 
persistent tumor. Early detection of those post-radiotherapy residual NPC is essential for early 
arrangement of salvage therapy. Detection methods include imaging, plasma Epstein-Barr virus 
DNA, endoscopy examinations and nasopharynx biopsy. 
- 
Narrow Band Imaging (NBI) is an optical image enhancement technology that improves the 
visibility of blood vessels. White light is composed of an equal mixture of wavelengths. The 
shorter wavelengths only penetrate the top layer of the mucosa, while the longer wavelengths 
penetrate deep into the mucosa. NBI light is composed of just two specific wavelengths that are 
strongly absorbed by hemoglobin: blue light (415 nm) and green light (540 nm). This wavelength 
allows a better understanding of the vasculature of suspect lesions. 
- 
NBI system has been well proven as a tool to detect early digestive tract cancer and head and 
neck cancer. However, there were only few studies targeting the detection of post-radiotherapy 
mucosal residual of NPC using NBI system 
Objective 
1. 
To identify the vessel pattern of those confirmed NPC case using NBI system 
2. 
To identify the endoscopy features of post-radiotherapy mucosal residual nasopharyngeal 
carcinoma using NBI system  
3. 
To establish the positive predicted value, negative predicted value, sensitivity and specificity of 
using both normal white light (WL) endoscopy and NBI system for detecting mucosal residual 
NPC 
Design 
- 
Prospective cross sectional study 
Study Period: 

Protocol_-_NBI_for_residual_NPC ver 3 
 
- 
12/2015 – 12/2016 for case recruitment  
- 
Every patient follow up time around 4 months ( till 4/2017) 
- 
Present at College Annual Scientific Meeting in 11/2017 
Inclusion Criteria 
- 
New NPC patient 
Exclusion Criteria 
- 
History of radiotherapy to head and neck region 
- 
Poor premorbid status/ non-communicable patients 
- 
<18 years old 
- 
Pregnancy 
Method 
1 
A New ENT NBI clinic is established and held on every Friday pm (preferably) and Wednesday 
am (in case the patient is not available on Friday pm session or Friday is a public holiday) 
2 
Newly biopsy confirmed NPC patient 
2.1 
Department of ENT: All biopsy confirmed NPC patients will be called back to the NBI 
clinic. They will be assessed by Dr. Fergus Wong and a complete ENT examination would 
be performed. Patient will undergo endoscopy examination (both WL + NBI), endoscopy 
image will be stored in the ePR system, consent forms will be signed and, baseline pure tone 
audiogram will be arranged. Patients will also be referred to oncology department. 
2.2 
Department of Oncology: All new biopsy confirmed NPC patients will be referred to ENT 
NBI clinic. They will be assessed by Dr. Fergus Wong and a complete ENT examination 
would be performed. Patient will undergo endoscopy examination (both WL + NBI), 
endoscopy image will be stored in the ePR system, consent forms will be signed and, 
baseline pure tone audiogram will be arranged. 
3 
All patients will be followed up by both oncology and ENT department (in ENT general clinic) 
together regularly and look for chemo-radiation complication and hearing impairment. 
4 
At post-radiotherapy (2nd weeks) follow up in oncology department 
4.1 
An appointment at post-radiotherapy 8th weeks will be arranged for the ENT NBI clinic 
(preferably on Friday pm) to perform nasopharynx biopsy  
4.2 
An appointment at post-radiotherapy 10th weeks will be arranged for the oncology clinic to 
review biopsy result 
5 
At post-radiotherapy 8th weeks NBI clinic: The patient will undergo endoscopy examination (both 
WL and NBI) and nasopharyngeal biopsy will be taken. All the images will be saved in ePR. The 
consultation note template will be as same as the oncology endoscopy session template. 
6 
Biopsy results will be reviewed by oncology colleagues at the post-radiotherapy 10th weeks clinic 
Analysis 
- 
Results will be process and analyzed as mean +/- standard deviation for continuous variables, and 
percentage for categorical variable. 
- 
Positive predicted value, negative predicted valve, sensitivity, specificity of both white light and 
NBI system will be calculated 

Protocol_-_NBI_for_residual_NPC ver 3 
 
- 
Statistical difference will be compared by chi-square test. P<0.05 was set as statistically 
significant 
- 
Statistical analysis will be carried out with SPSS version 13 
Ethic issue/ Major point in consent form 
- 
Prolonged the endoscopy examination time 
Target Patient number: 
- 
New case: 50-70 
Reference  
1 
Wang WH, Lin YC, Chen WC, Chen MF, Chen CC, Lee KF. Detection of mucosal recurrent 
nasopharyngeal carcinomas after radiotherapy with narrow-band imaging endoscopy. Int J Radiat 
Oncol Biol Phys. 2012 Jul 15;83(4):1213-9.  
2 
Wang WH, Lin YC, Lee KF, Weng HH. Nasopharyngeal carcinoma detected by narrow-band 
imaging endoscopy. Oral Oncol. 2011 Aug;47(8):736-41. 
3 
Feng Liu, Jian-ping Xiao, Guo-zhen Xu, Li Gao, Ying-jie Xu, Ye Zhang, Xue-song Jiang, Jun-lin 
Yi, Jing-wei Luo, Xiao-dong Huang, Fu-kui Huan, Hao Fang, Bao Wan and Ye-xiong Li. 
Fractionated stereotactic radiotherapy for 136 patients with locally residual nasopharyngeal 
carcinoma. Radiation Oncology 2013, 8:157   
4 
Ho CY, Chan KT, Chu PY. Comparison of narrow-band imaging and conventional 
nasopharyngoscopy for the screening of unaffected members of families with nasopharyngeal 
carcinoma. Eur Arch Otorhinolaryngol. 2013 Sep;270(9):2515-20. 
5 
Lin YC, Watanabe A, Chen WC, Lee KF, Lee IL, Wang WH. Narrowband imaging for early 
detection of malignant tumors and radiation effect after treatment of head and neck cancer. Arch 
Otolaryngol Head Neck Surg. 2010 Mar;136(3):234-9.  
6 
Wen YH, Zhu XL, Lei WB, Zeng YH, Sun YQ, Wen WP. Narrow-band imaging: a novel screening 
tool for early nasopharyngeal carcinoma. Arch Otolaryngol Head Neck Surg. 2012 
Feb;138(2):183-8.