title: Diagnosis of post-radiotherapy local failures in nasopharyngeal carcinoma: a prospective institutional study.
abstract: BACKGROUND
  This prospective study was conducted to evaluate and compare the efficacies of nasopharyngoscopy and CT scan in the diagnosis of local failure of external beam radiotherapy (EBRT) for nasopharyngeal carcinoma.
  
  
  METHODS
  Total 52 patients of histopathologically proven nasopharyngeal carcinoma treated with external beam radiotherapy (EBRT), were included in this study. For every patient computed tomography (CT), nasopharyngoscopy and nasopharyngeal biopsies were performed 3 months after completion of EBRT.
  
  
  RESULTS
  Three months after completion of EBRT, 9 patients (17.3%) had evident disease on histological examination of biopsies. Nasopharyngoscopy showed 77.78% sensitivity, 93.03% specificity, 70% positive predictive value and 95.24% negative predictive value in diagnosing the residual/recurrence of tumor. There was statistically significant agreement between the endoscopic findings and the histological findings (Kappa reliability coefficient=0.562, p<0.01). On the other hand, CT scan showed a 55.56% sensitivity, 39.53% specificity, 16.13% positive predictive value and 80.95% negative predictive value in diagnosing the residual tumor/recurrence. There was no statistically significant agreement between the CT scan findings and the histological findings (Kappa reliability coefficient = 0.038, p>0.05).
  
  
  CONCLUSIONS
  Nasopharyngoscopy should be considered the primary follow-up tool after radiotherapy of nasopharyngeal carcinoma. CT scan should be reserved for patients with histological or any symptomatic indications. Routine postnasal biopsies are not required.
authors.affiliation: Dept. of Radiation Oncology, Acharya Tulsi Regional Cancer Treatment & Research Institute, Bikaner-334003, Rajasthan, India.
authors.forename: Puneet Kumar
authors.initials: PK
authors.lastname: Bagri
authors.affiliation: Dept. of Radiation Oncology, Acharya Tulsi Regional Cancer Treatment & Research Institute, Bikaner-334003, Rajasthan, India.
authors.forename: Mukesh Kumar
authors.initials: MK
authors.lastname: Singhal
authors.affiliation: Dept. of Radiation Oncology, Acharya Tulsi Regional Cancer Treatment & Research Institute, Bikaner-334003, Rajasthan, India.
authors.forename: Daleep
authors.initials: D
authors.lastname: Singh
authors.affiliation: Dept. of Radiation Oncology, Acharya Tulsi Regional Cancer Treatment & Research Institute, Bikaner-334003, Rajasthan, India.
authors.forename: Akhil
authors.initials: A
authors.lastname: Kapoor
authors.affiliation: Dept. of Radiation Oncology, Acharya Tulsi Regional Cancer Treatment & Research Institute, Bikaner-334003, Rajasthan, India.
authors.forename: Shankar Lal
authors.initials: SL
authors.lastname: Jakhar
authors.affiliation: Dept. of Radiation Oncology, Acharya Tulsi Regional Cancer Treatment & Research Institute, Bikaner-334003, Rajasthan, India.
authors.forename: Neeti
authors.initials: N
authors.lastname: Sharma
authors.affiliation: Medical Oncology section, Acharya Tulsi Regional Cancer Treatment & Research Institute, Bikaner-334003, Rajasthan, India.
authors.forename: Surender
authors.initials: S
authors.lastname: Beniwal
authors.affiliation: Dept. of Radiation Oncology, Acharya Tulsi Regional Cancer Treatment & Research Institute, Bikaner-334003, Rajasthan, India.
authors.forename: Harvindra Singh
authors.initials: HS
authors.lastname: Kumar
authors.affiliation: Dept. of Radiation Oncology, Acharya Tulsi Regional Cancer Treatment & Research Institute, Bikaner-334003, Rajasthan, India.
authors.forename: Ajay
authors.initials: A
authors.lastname: Sharma
authors.affiliation: Dept. of Radiation Oncology, Acharya Tulsi Regional Cancer Treatment & Research Institute, Bikaner-334003, Rajasthan, India.
authors.forename: Megh Raj
authors.initials: MR
authors.lastname: Bardia
keywords: Biopsy; CT scan; Local failure; Nasopharyngeal carcinoma; Nasopharyngoscopy