Radiological differences in computed tomography findings and texture analysis between cystic lymph node metastases of human papillomavirus-positive oropharyngeal cancer and second branchial cysts

PURPOSE: The study aimed to analyse radiological differences in computed tomography (CT) findings and texture analysis between cystic lymph node metastases (CNM) in human papillomavirus (HPV)-positive oropharyngeal cancer (OPC) and second branchial cleft cysts (2(nd) BC). MATERIAL AND METHODS: Patients with pathological evidence of CNM-HPV-OPC and 2(nd) BC, who underwent contrast-enhanced CT, were retrospectively evaluated. The evaluated characteristics include age, sex, and CT findings. CT findings included the maximum and minimum transverse diameters, maximum caudal diameter, thickness of the peripheral wall, presence of internal septation, presence of surrounding fat stranding, location, and 40 texture parameters. RESULTS: A total of 13 patients had CNM-HPV-OPC (19 lesions), while 20 patients had 2(nd) BC (20 lesions). Patients with 2(nd) BC were significantly younger than those with CNM-HPV-OPC (p < 0.001). In terms of diameter, 2(nd) BC lesions were significantly larger than the CNM-HPV-OPC lesions (p < 0.001). CNM-HPV OPC lesions had significantly thicker walls than 2(nd) BC lesions (p < 0.001). CNM-HPV-OPC lesions had significantly higher association with internal septations than 2(nd) BC lesions (p < 0.001). Second BC lesions were significantly less common at level III than CNM-HPV-OPC lesions (p = 0.047). Among the 40 texture parameters measured, 8 had significant differences (p ≤ 0.001). CONCLUSIONS: There were significant differences in CT findings and textural parameters between CNM-HPV-OPC and 2(nd) BC lesions. These results may help in differentiating one from the other.