Endocervical adenocarcinoma in situ

For the cytology see Endocervical adenocarcinoma in situ (cytology)

Endocervical adenocarcinoma in situ, also adenocarcinoma in situ of the uterine endocervix, is pre-invasive change of the uterine endocervix. It is closely tied to HPV infection.

If the context is clear, it may be referred to as adenocarcinoma in situ, abbreviated AIS.

General

• Usually due to HPV.
• May be found together with squamous neoplasias of the cervix.
• AIS of the cervix is much less common than squamous dysplasia of the cervix/SCC of the cervix.
• Generally, definitely diagnosed with an endocervical curettage (ECC).

Gross

• Not apparent at colposcopy.

Microscopic

Features:

1. Nuclear changes - key feature:
   • Variable nuclear stratification.
     • Nuclear crowding/pseudostratification.
   • Nuclear enlargement.
     • Often cigar-shaped nuclei.
   • Coarse chromatin.
   • Small nucleolus or nucleoli.
2. +/-Mitoses.
3. +/-Reduced cytoplasmic mucin.
4. Preservation of glandular architecture.
   • Normal gland spacing - lack of complexity ("lobular pattern").
   • Normal gland depth (subjective).

DDx:

• Tubal metaplasia.
• Arias-Stella reaction.
• Endometriosis.
• Lower uterine segment epithelium - esp. proliferative phase endometrium - mitoses rare, NC ratio normal, stroma different.
• Endocervical adenocarcinoma - often has paradoxical maturation... paler cytoplasm & nuclei than adjacent AIS.
• Metastatic adenocarcinoma.
• Proliferative phase endometrium - endometrial type stroma, cytoplasm not pale staining, no nuclear atypia (smooth nuclear contour, stratified).

Images

• Endocervical AIS adjacent to normal (flickriver.com/euthman).
• Endocervical adenocarcinoma in situ (techriver.net).
• Endocervical adenocarcinoma in situ (womenshealthsection.com).
• Endocervical adenocarcinoma in situ - cytology (techriver.net).

IHC

• p16 +ve.
• CEA +ve.
• Vimentin -ve.

See also

• Endocervical adenocarcinoma.
• Uterine cervix.