Mean nuclear area and chromosomal DNA content of squamous cell carcinomas of the oral cavity using computerized image analysis

Morphometric measurements of nuclei may be of prognostic value in some cancers. In this present study we have evaluated the mean nuclear area (MNA) of 50 squamous cell carcinomas of the oral cavity (SCCOC) using computerized image analysis. Since chromosomal DNA content is a reflection of the DNA content in the nucleus, we have evaluated the relationship between MNA and chromosomal DNA. Thirteen tumours had a MNA greater than 49.9 μm2 and 37 had a MNA less than this. Six tumours were classified as hypodiploid, 29 as diploid and 15 as aneuploid. There were 44 node-negative patients and six node-positive. When comparing MNA in these groups, 50 per cent of node-positive patients had a larger MNA whilst only 20 per cent of the node-negative group had a large MNA. The correlation coefficient between MNA and DNA indices was r = 0.75. The greater nuclear size is possibly a reflection of a more aggressive tumour biology in the node-positive patients. We conclude that a large MNA may be a marker of aggressive tumour biology in this group. In the future, we aim to evaluate the prognostic significance of MNA in patients with SCCOC.

DECREASE IN CHROMOSOMAL DNA CONTENT AT HIGHER POLYPLOIDY LEVEL IN VICIA FABA ROOT MERISTEMS

The DNA content of the nucleus is expected to increase proportionately with the increase of ploidy. Estimation of the DNA content of the endopolyploid root meristem nuclei of Vicia faba has been done through cytophotometry from 2n to 16n level. Observations indicate that a decline in nuclear DNA content takes place at higher ploidy level while the overall karyological integrity of the chromosomes and their number are apparently maintained as normal.