There is significant amount of research done
on Oral Squamous cell carcinoma (OSCC). One research
technique is immunohistochemical (IHC) analysis using
whole sections. With little availability of OSCC tissues
high throughput analysis such as Tissue Microarray
(TMA) are capable of efficient analysis of small samples.
However, the results become questionable if the tumor
exhibits high degree of heterogeneity as TMA cores might
not accurately represent the whole section. Aim: The aim
of this study is to determine the optimal number of TMA
cores required to provide an accurate representation of
the whole section with IHC analysis in OSCC. Materials
and Methods: Twenty tissue samples stained with
anti-p53 antibody were scanned at 40x magnification.
Three to six virtual cores of size 0.6 mm, 1.0 mm and
1.5 mm were drawn on the scanned slides. H-scores
were obtained for both whole sections and cores using
NuclearQuant (3DHistech, Budapest, Hungary) software
after eliminating non-tumour cells and artifacts manually.
The correspondence between the cores and whole sections
were calculated using intra-class correlation and one
sample t-test. Results: Good correlation was obtained
with just a single core of 0.6mm (0.826). Subsequent
increase in core number and size resulted in improved
correlation coefficient and smaller confidence interval.
Conclusion: Three TMA cores of 0.6 mm would be the
most optimal, as not only was there very strong correlation
with the whole tissue section, the extra core will also be
able to act as confirmation if the results of the first 2 cores
are in doubt.