Abstract: OBJECTIVE To analyze the narrow-band imaging(NBI)endoscopic characteristics of recurrent early glottic carcinoma patients after undergoing CO2 laser surgery with a suspend laryngoscopy.METHODS A retrospective study was conducted on patients with early-stage glottic carcinoma(Ⅰ-Ⅱ stage)who received CO2 laser surgery under supportive laryngoscopy at the Department of Otolaryngology Head and Neck Surgery,the Second Affiliated Hospital of Xi'an Jiao Tong University from January 2017 to December 2023.The medical history,treatment methods,laryngoscopy(including common white light endoscopy and NBI endoscopy),imaging examinations,and pathological results of patients with recurrent glottic carcinoma were collected at different time points including preoperation,postoperative 1 month,postoperative 3 months,and postoperative 6 months.The endoscopic characteristics of NBI in patients with recurrent glottic carcinoma were summarized.RESULTS First,among 18 patients with early-stage glottic cancer recurrence after CO2 laser,the diagnostic rate of NBI endoscopy for laryngeal cancer recurrence(88.89%,16/18)was significantly higher than that of common white light endoscopy(55.56%,10/18)(χ2=4.985,P=0.026).The intraepithelial papillary capillary loop(IPCL)was classified as a vertical vessel according to ELS in all relapsed patients.However,according to Ni classification,the IPCL of the 72.22%(13/18)were classified as type V,while the IPCL of 27.78%(5/18)showed suspicious abnormal neovascularization(punctate or dilated and curved).The proportion of patients with abnormal IPCL on the surgical surface at 1 month,3 months,and 6 months postoperatively was 0.00%,27.78%(5/18),and 61.11%(11/18),respectively,with statistically significant differences(χ2=16.164,P<0.001),which indicated that the longer the follow-up time for recurrent laryngeal cancer patients,the higher the proportion of patients with abnormal IPCL on the surface of the surgical area under NBI endoscopy.CONCLUSION For early glottic carcinoma after CO2 laser surgery with a suspend laryngoscopy,the appearance of suspicious new blood vessels with type Ⅴ IPCL and punctate or dilated curvature under NBI endoscopy may indicate early recurrence of laryngeal cancer.