Lower Gastrointestinal Tract and Microsatellite Instability

摘要: Use of immunohistochemistry in the diagnostic gastrointestinal pathology lower GI tract is similar to that upper tract. CK20, CK7, and CDX-2 are probably most commonly used markers can identify histogenesis vast majority carcinomas. Tumors neuroendocrine origin also common tract, for these, CDX-2, synaptophysin, chromogranin immunostains very helpful. Diagnosis tumors mesenchymal generally straightforward based on tumor histology with help immunohistochemistry. The differential diagnosis between appendiceal mucinous ovarian muci­nous occasionally could be challenging because two share significant similarities both his­tology immunophenotype. As microsatellite instability (MSI) thought play a role not only tumorigenesis but prognosis response adjuvant chemo­therapy regimens, MSI testing becoming popular. In general, PCR-based tests correlate well. Immunohistochemical studies approximately 90–95% sensitive hereditary nonpolyposis colorectal cancer (HNPCC) syndrome. Finally, conjunction immunohistochemistry, molecular may broaden its use practice as demonstrated by K-ras BRAF mutation test