Predicting the early invasiveness of nasopharyngeal mucosal neoplasia after radiotherapy by narrow-band imaging: A pilot study

Background This study evaluated the correlation between the histologic findings of nasopharyngeal mucosal neoplasias after radiotherapy and narrow-band imaging (NBI) endoscopic findings. Methods One hundred six patients were enrolled. All patients underwent conventional white-light endoscopic examinations of the nasopharynx, which were followed by NBI endoscopy. Biopsy specimens were obtained if scattered brown-spotted lesions were identified. Results We identified 22 patients with brown-spotted lesions by NBI endoscopy. Histopathologic study confirmed that 4 lesions were neoplastic, including 2 dysplastic lesions and 2 carcinomatous lesions. According to pathologic examinations, the thickness of the epithelium in carcinomatous, dysplastic, and nonneoplastic lesions were (mean ± SD) 0.85 ± 0.21 mm, 0.45 ± 0.21 mm, and 0.35 ± 0.07 mm, respectively. The epithelial thickness of carcinomatous and dysplastic lesions was significantly thicker than that of nonneoplastic lesions (p <.001 and p =.026, respectively). According to the NBI endoscopic examinations, the epithelial thickness of the brown-spotted lesions with irregular borders was significantly thicker than those lesions with tailed/round borders (0.48 ± 0.24 mm vs 0.26 ± 0.07 mm, p =.009). Visualization by NBI corresponded to the histopathologic findings; the prevalence of neoplastic lesions with tailed/round borders and irregular borders was 0% (0/13) and 44.4% (4/9), respectively (p =.017). Conclusions This study demonstrates that lesions with an irregular pattern tend to be neoplastic lesions. Irregularities observed under NBI are important pathologic indicators of the early invasiveness of nasopharyngeal mucosal neoplasia after radiotherapy. This result warrants further inquiry to confirm its accuracy.