Abstract
Oral ulcers are often neglected in patients with AIDS. However, giant oral ulcers are uncommon and are usually suspected to be malignant lesions. Our study presents a case of giant ulcers in an AIDS patient that were initially suspected to be oral cancer. To assist with diagnosis, conventional microbiological tests, metagenomic next-generation sequencing, and a pathological examination were conducted on oral lesion biopsy specimens. The case was finally confirmed via hematoxylin-eosin staining and immunohistochemical staining to be a cytomegalovirus infection.