Comparison of TMA Technique and Routine Whole Slide Analysis in Evaluation of Proliferative Markers Expression in Laryngeal Squamous Cell Cancer

Background/Aim: Comparison of the expression of Ki-67, MCM3, 5, 7 and MTI/II proteins using immuno- histochemistry (IHC) on whole section (WS) and tissue microarray (TMA) of laryngeal squamous cell carcinoma (LSCC) samples. Materials and Methods: A total of 51 archival paraffin blocks of LSCC were used. TMAs were prepared from 1.5 mm core punches. IHC reactions were performed using antibodies against Ki-67, minichromosome maintenance proteins (MCM3, 5, 7) and metallothionein (MTI/II). Results: Spearman rank correlation test revealed moderate positive correlation in the case of Ki-67: WS vs. TMA (r=0.38, p=0.07) and strong positive correlation in regard to the rest of tested markers: MCM3, WS vs. TMA (r=0.49, p=0.0004); MCM5, WS vs. TMA (r=0.61, p<0.0001); MCM7, WS vs. TMA (r=0.59, p<0.0001); MTI/II, WS vs. TMA (r=0.66, p<0.0001). Mann Whitney U-test showed no significant differences in the case of Ki-67 and MCM5. Moreover, Bland-Altman test showed a low level of bias in regard to Ki-67, WS vs. TMA and MCM5, WS vs. TMA. Conclusion: TMA may be an effective and reliable method of assessment of Ki-67 and MCM5 expression in LSCC.