RESUMO
Context: HER2-targeted therapy has been shown to benefit HER2-positive gastric cancer. It is very important to determine the HER2 expression level correctly to select the appropriate test and sampling method. Aim: In this study, we investigated the frequency of overexpression of HER2 and intratumoral heterogeneity of HER2-positive cases, comparison of HER2 used immunohistochemistry (IHC) and fluorescence in situ hybridization (FISH) performance in biopsy and resection specimens, the correlation of HER2 status between biopsy and resection specimens, and its relationship with clinicopathological findings. Materials and Methods: Formalin-fixed, paraffin-embedded specimens of a total of 40 surgically resected and biopsy specimens of gastric cancer were analyzed. HER2 status was examined using both IHC and FISH techniques, and the findings and their association with different clinicopathological parameters were evaluated. Results: The concordance rate between the results of IHC and FISH in biopsy and resection specimens was 96.6% and 86.6%, respectively. In paired 20 cases, the overall concordance rate of HER2-IHC and HER2-FISH status between biopsy and resection specimens was 90% and 100%, respectively. HER2-IHC analysis revealed that 5/40 cases were IHC 2+ and only 1 of 5 IHC 2+ cases demonstrated HER2-FISH amplification. Conclusion: Our results showed that HER2-IHC was well concordant with FISH in cases with a score of 0/1+ or 3+ and demonstrates strong concordance between biopsy and resection specimens. FISH should be performed when the IHC result is equivocal. In our study, no statistically significant correlation was observed between HER2 positivity and clinicopathological parameters. Overall, both biopsy and resection specimens are appropriate for HER2 testing.
RESUMO
Context: p16 is an important tumor suppressor gene and responsible for regulating the cell cycle. Diffuse positivity with p16 in the cervix and head/neck carcinomas can be regarded as a surrogate marker of the presence of high-risk human papillomavirus (HPV). Aim: The aim of our study was to search the existence of p16 expression in pterygium. We also analyzed the association of p16 expression with epithelial dysplasia and HPV expression. Subjects and Methods: The study enrolled 75 cases of pterygium. The conjunctival tissues of 10 patients excised by the strabismus surgery were used as control group. All of the slides were stained with p16 via the immunohistochemical method. Results: 49 (65%) of pterygiums showed low-grade epithelial dysplasia. None of the control groups showed dysplasia. Positive expression of p16 in patient group was significantly higher (P < 0.001). Staining percentage (SP) of p16 was between 0 and 26% in pterygium; mean SP was 5.1%. There was no staining in the control group. A total of 59 (72%) pterygium cases were positive with p16. Appoximately 42 of 49 (85%) cases with dysplasia showed p16 staining. There was a significant relation between dysplasia and positive expression of p16 (P < 0.001). Conclusions: P16 is significantly expressed in pterygium and correlated with epithelial dysplasia. Furthermore, the existence of p16 expression suggests that HPV is a possible ethiological factor in pterygium. We think that examination of p16 expression and analysis of HPV DNA in p16 positive cases can help us to understand the etiopathogenesis of the disease better.