Carcinoma of the uterine cervix. Etiology, pathogenesis, types, microscopic & gross pathomorphology
Most common cervical carcinomas are squamous cell carcinomas, followed by adenocarcinomas and mixed adenosquamous carcinomas. Almost all are caused by HPV. Peak incidence about 45 years, about a decade after peak incidence of CIN. Risk factors include smoking and HIV.
Invasive carcinomas develop in the transformation zone of the cervix, and can undergo microscopic invasion or gross exophytic growth. Tumours encircle the cervix and penetrate the stroma below to form a barrel cervix. There is a high chance of lymph metastasis.
Gross: a grey-white, ulcerated squamous carcinoma has replaced and expanded the whole cervix (barrel cervix); the uterine body above is spared.
Image: “Squamous cell carcinoma cervix” by Department of Pathology, Calicut Medical College, CC BY-SA 4.0, via Wikimedia Commons.
Example: a 45-year-old woman who missed her smear tests presents with postcoital bleeding and a friable, exophytic cervical mass. Advanced tumours spread into the parametria and can encircle the ureters; the resulting hydronephrosis and renal failure is a classic cause of death.
CIN III dysplasia is the precancerous lesion (see above for full pathogenesis) and should be observed on smear tests.