gynecology and obstetrics
Cervical Cancer
Pathology of Cervical Cancer
The cervix is composed of stroma and epithelium. The ectocervix protrudes into the vagina and is lined with squamous epithelium. The endocervix (a canal that passes from the internal os to the external os) is lined with columnar epithelium. Nearly all cervical carcinomas originate in the transformation zone, which surrounds the external os; the transformation zone is an area of squamous metaplasia between the original and current squamocolumnar junction ( Pathology reference ). Cervical intraepithelial neoplasia (CIN) is graded as 1: Mild cervical dysplasia 2: Moderate dysplasia 3: Severe dysplasia and carcinoma in situ CIN3 is unlikely to regress spontaneously; if untreated, it may, over months or years, penetrate the basement membrane, becoming invasive carcinoma. About 80 to 85% of all cervical cancers are squamous cell carcinoma; most of the rest are adenocarcinomas. Sarcomas and small cell neuroendocrine tumors are rare. Invasive cervical cancer usually spreads by direct extension into surrounding tissues or via the lymphatics to the pelvic and para-aortic lymph nodes. Hematogenous spread is possible but rare. If cervical cancer spreads to the pelvic or para-aortic lymph nodes, the prognosis is worse, and the location and size of the radiation therapy field is affected. 1.Bhatla N, Aoki D, Sharma DN, et al: Cancer of the cervix uteri: 2021 update.Int J Gynaecol Obstet155 Suppl 1:28-44, 2021. doi: 10.1002/ijgo.13865 