RB1 and endometrial carcinoma: A study conducted by Bures et al suggested that PSCCE exhibits molecular alterations involving the pRB-cyclin D1-CDK4/6-p16 pathway and pTEN.[9] Compared with type I endometrial carcinoma, PSCCE has a unique pathogenesis.[9] No evidence of squamous metaplasia, atypical hyperplasia, or HPV infection was found in our patient, and no cancer was found in the mucosa or stroma of the cervical canal.