Background. Nucleolar organizer regions (AgNORs) are associated with proliferative activity and ploidy in many tumors. The endocervical growth pattern of cervical adenocarcinoma renders tumor volume assessment more difficult, necessitating additional prognostic indicators.
Methods. Thirty-five cases of cervical adenocarcinoma were evaluated by reviewing charts and histologic sections. Nucleolar organizer regions were stained and counted manually; the mean number per cell and the percentage of cells with more than 5 AgNORs were recorded. Ploidy and S-phase fraction were determined by flow cytometry.
Results. Mean AgNOR counts per cell were significantly higher in adenocarcinoma (3.0) and adenosquamous carcinoma (4.3) than in benign endocervical epithelium (1.4). Grade 3 tumors had higher values (4.0) than Grade 1 lesions (2.9), and tumors with lymphovascular space involvement had higher values (3.5) than tumors without such involvement (2.7). No significant correlation was seen with regard to tumor stage or size. Flow cytometric parameters did not correlate with any of the examined parameters, although the DNA index was higher in larger tumors. Correlation between AgNOR counts and flow cytometry was significant only in Grade I tumors.
Conclusions. Nucleolar organizer region counts correlated better with histologic parameters of cervical adenocarcinoma than did flow cytometry. Because it is easily performed and does not require sophisticated equipment, AgNOR counts should be investigated further in a larger group of patients to determine their prognostic value.