Tissue markers of cellular proliferation have been utilized as prognostic indicators in tumors of the central nervous system. Nucleolar organizer regions represent transcriptionally active sites of ribosomal deoxyribonucleic acid and can be identified...
Tissue markers of cellular proliferation have been utilized as prognostic indicators in tumors of the central nervous system. Nucleolar organizer regions represent transcriptionally active sites of ribosomal deoxyribonucleic acid and can be identified by a simple argyrophilic technique. The authors describe a standardized approach to the assessment of these argyrophilic nucleolar organizer regions(AgNORs) in 25 astrocytomas(including 6 glioblastomas), 6 oligodendrogliomas and 1 xanthochromic astrocytoma, which were also estimated in association with 2-year survival post-operatively. Appropriate sections were silver stained and AgNORs were counted in 1000 cells.
In cases of astrocytoma, the mean AgNORs/cell count of group survived more than 2 years after operation was significantly different from that survived less than 2 years : 1.93±1.13 vs. ≥ 4.79±3.90.
And the mean AgNORs/cell count was 1.53±0.32 in low grade astrocytoma. 2.03±0.59 in grade Ⅲ astrocytoma, and ≥6.64±3.77 in grade Ⅳ astrocytoma. Among the patients with the same grade astrocytoma, the mean AgNORs/cell count was lower in the cases of long survival rather than short survival.
The assessment of AgNORs can be easily performed by any surgical pathology laboratory without specialized equipment. It may be used as a valuable and independent prognosticator of biological behavior in cases of astrocytoma.