Colon Cancer Pathology of Hereditary Forms
Approximately 5 % of all colorectal carcinomas are due to a defined single genetic defect causing hereditary disease. Gross and microscopic pathologic examination of the resection or biopsy specimen can help identify an unsuspected case of hereditary colorectal carcinoma due to the characteristic morphologic findings seen in some syndromes. Additional immunohistochemical and molecular studies can then provide a definitive diagnosis. Furthermore, due to the germline nature of mutations in these syndromes, various extracolonic manifestations may be the first sign of the disease, and knowledge of such associations can greatly improve the quality of care for these patients.
Colorectal Cancer in Lynch Syndrome (Hereditary Nonpolyposis Colorectal Cancer)
The most common form of hereditary colorectal carcinoma is Lynch syndrome (synonymhereditary nonpolyposis colorectal cancer, HNPCC) caused by inactivating mutation(s) in genes for DNA mismatch repair (MMR)...