Immunohistochemical analysis of mismatch repair proteins in iranian colorectal cancer patients at risk for Lynch syndrome

Hereditary non-polyposis colorectal cancer [HNPCC] is a common hereditary cancer predisposing syndrome has molecular and clinicopathological features still have remained ambiguous within Iranian populations. We discuss in this article some molecular and clinicopathological features of the condition. The study was a descriptive retrospective and designed on 1659 colorectal cancer [CRC] patients were screened based on early-onset disease and Amsterdam II criteria during 14 years [2000-2013]. Immunohistochemistry [IHC] staining was set up to detect expression of mismatch repair [MMR] genes on paraffin-embedded tissue sections of 31 HNPCC-CRC tumors. SPSS 19 software was used to analyze the data. IHC-MMR staining was absent in 7/31 individuals [22.6%] of which 4 cases showed IHC-Absent [IHC-A] in both MSH2 and MSH6 [57.1%], in 2 cases both MLH1 and PMS2 had negative staining [28.6%], and just in one case, MSH6 was defective [14.3%]. The frequency of CRC among IHC-A and IHC-Present [IHC-P] families was 67.5% and 27.9%, respectively. Also the most frequent extracolonic cancers in IHC-A group were: stomach [10%], small bowel [5%], and prostate [5%]; and in IHC-P group: stomach [18.4%], lung [10.9%], and breast [7.5%]. Average age of IHC-A individuals at diagnosis was 38.0 versus 45.3 years in IHC-P individuals. Overall, 20.8% and 57.1% of our index CRCs were localized proximal to the splenic flexure in IHC-P and IHC-A groups, respectively. Given the lack of enough information about molecular aspects of hereditary cancer syndromes like HNPCC in Iran, more evaluations are necessary on larger samples using complementary techniques such as MSI-testing and mutation analyses

Role of E-cadherin in differentiation between squamous and basal cell carcinoma

Some type of basal cell carcinoma [ex Keratotic variant] is often misdiagnosed as squamous cell carcinoma and basal cell carinoma. The objective of this study was to determine the role of E-cadherin in differentiation between Squamous and basal cell carcinoma. The sampling was performed by simple method. Entry criteria to the study included 2 groups of 34 primary, untreated BCCs and SCCs each from a different patient. They were surgically removed and the diagnosis was confirmed by histopathology. The stained sections were scored by levels of expression and intensity of E-cadherin. Distribution of E-cadherin staining was more in BCC than SCCs [P=0.006] but the decreased staining intensity of E-cadherin in SCC compared with BCC was not statistically significant [P=0.056]. When the results [score of distribution and intensity of E-cadherin] were added together, the acquired E-cadherin index in a statistical analysis was meaningful to differ between SCC and BCC [P=0.002]. Our study showed that E-cadherin distribution and index but not intensity is lower in SCC cells than BCC cells and it can justify the cause of metastasis in SCC. However, this is ambiguous to use it for differentiating of aggressive forms of BCCs from SCCs, practically