Quantitation of nucleolar organizer regions by image analysis in glottic squamous cell carcinoma.

OBJECTIVE

To apply computer image analysis as a quantitative method for analyzing interphase nucleolar organizer regions (NORs) to determine whether this proliferative marker provides useful prognostic information in glottic squamous cell carcinoma.

DESIGN

Retrospective testing of biopsy samples and resected tissue.

SETTING

Nova Scotia Regional Cancer Centre and regional hospitals in Nova Scotia and Prince Edward Island, Canada.

PATIENTS

Patients with primary glottic cancer presenting to the cancer centre between 1984 and 1991.

INTERVENTIONS

Semiautomated image analysis was used to measure the nuclear area and the NOR area in formalin-fixed paraffin-embedded tumour samples.

OUTCOME MEASURES

Mean nuclear area, mean NOR area and NOR percentage of nuclear area, calculated as the mean NOR area divided by the mean nuclear area, expressed as a percentage.

RESULTS

Of 154 cases, 90 samples were received; however, 8 paraffin blocks were exhausted and 29 samples stained poorly due to extent of fixation. Analysis of the remaining 53 cases, all primary squamous cell carcinomas, showed no statistically significant association between, on one hand, mean NOR area or NOR percentage of nuclear area and, on the other hand, tumour grade, tumour stage, tumour recurrence or disease-related death.

CONCLUSIONS

This study does not demonstrate a prognostic value of NOR measurement as a proliferative marker in primary glottic squamous carcinoma. However, given the small number of cases in this study, further research should be conducted using a larger number of cases from one centre and comparing NOR measures with other markers of cell proliferation.