Nucleolar organiser regions in adenocarcinoma in situ of the endocervix.

The AgNOR technique was used to analyse 11 cases of adenocarcinoma in situ of the endocervix and five examples of healthy cervices to assess whether areas of "increased nuclear activity" could be located adjacent to the malignant tissue. Areas of adenocarcinoma in situ had significantly more AgNOR staining dots than apparently normal bordering areas ("transitional areas") and areas of endocervical epithelium remote from adenocarcinoma in situ. There were no significant differences between AgNOR counts in transitional areas and areas remote from adenocarcinoma in situ, and between these areas and histologically normal cervices. These observations provide no support for the hypothesis that areas of glandular atypia of lesser severity or zones of "increased nuclear activity" exist adjacent to adenocarcinoma in situ.