Morphological and biological characteristics of cervical adenocarcinoma and adenocarcinoma in situ

Adenocarcinomas constitute 5 – 10 % of all carcinomas arising in the cervix.
Several histological types are recognised including endocervical adenocarcinoma, endometrial adenocarcinoma and clear cell carcinoma. The endocervical type is most commonly found and most readily recognised in cervical smears. However, it is not uncommon for more than one type of adenocarcinoma to be present in a single tumour
The frequent coexistence of cervical adenocarcinoma with squamous carcinoma suggest that they have a common aetiology and pathogenesis. HPVDNA is found in both and both are associated with the same risk factors.
Endocervical adenocarcinoma may be polypoid or ulcerative. The tumour is composed of branched and budding glands lined by mucin producing neoplastic cells which resemble the glandular cells lining the endocervical canal. Three grades of adenocarcinoma are recognised well differentiated, moderately differentiated and poorly differentiated according to how closely the morphology of the tumour resembles that of the endocervix.
Endocervical adenocarcinoma in situ is considered to be the glandular counterpart of cervical intraepithelial neoplasia and a precursor of invasive adenocarcinoma.
Although the invasive and the in situ forms of endocervical adenocarcinoma can be recognised in histological section, a reliable distinction cannot be made from the appearance of the cells in the cervical smear.

Histology of adenocarcinoma of cervix

Adenocarcinomain situ.
The characteristic feature of AIS is replacement of normal columnar epithelium of the endocervical canal by neoplasic cells with hyperchromatic nuclei which is clearly shown in this section. The structure of the glands is in tact.

Endocervical adenocarcinoma (well differentiated)
Endocervical adenocarcinomas are composed of branching and budding glands lined by neoplastic cells which in the well diffrerentiated carcinomas resemble the glandular cells lining the endocervical canal. The tumour is invading the stroma and there is loss of the normal gland architecture.

Endocervical adenocarcinoma (well differentiated).
Endocervical adenocarcinomas are composed of branching and budding glands lined by neoplastic cells which in the well diffrerentiated carcinomas resemble the glandular cells lining the endocervical canal. There is marked nuclear hyperchromasia, cellular crowding, and pseudostratification.

Endocervical adenocarcinoma (poorly differentiated).
Poorly differentiated endocervical adenocarcinomas show a tendancy to show a solid growth formation and gland formation is rare. Individual cells are barely recognisable as endocervical and show clear morphism with frequent mitotic figures.