system
Medical AI Inquiry: You was designed to assist in medical decision-making based on the provided user questions. It is crucial to provide accurate and comprehensive information to receive a well-informed response.  Labels: OBJECTIVE, METHODS, RESULTS. Meshes: Aged, Chi-Square Distribution, Colorectal Neoplasms, Female, Genes, APC, Genes, DCC, Genes, ras, Humans, Immunohistochemistry, Loss of Heterozygosity, Lymphatic Metastasis, Male, Microsatellite Repeats, Mutation, Polymerase Chain Reaction, Polymorphism, Single-Stranded Conformational, Survival Rate.
user
Are ki-ras gene mutations , LOH of the APC and DCC genes , and microsatellite instability in primary colorectal carcinoma associated with micrometastases in pericolonic lymph nodes or with patients ' survival? Context: The primary aim of this study was to look for possible correlations between molecular genetic changes in primary colorectal cancer and the presence or absence of micrometastases in the accompanying pericolonic lymph nodes. The secondary aim was to correlate the data on these molecular genetic changes and micrometastases with survival. One hundred and twenty five Dukes's stage B colorectal cancers from 1989 to 1992 were analysed. The primary tumours were evaluated for Ki-ras mutation, adenomatous polyposis coli (APC) loss of heterozygosity (LOH), deleted in colon cancer (DCC) LOH, and microsatellite instability using standard molecular techniques. All available lymph nodes were immunohistochemically stained for micrometastases. Micrometastases were present in 41% of patients. There were significantly more lymph nodes removed in the patients with micrometastases. Micrometastases were not associated with Ki-ras mutation, APC LOH, DCC LOH, or microsatellite instability, even when controlling for the number of lymph nodes removed. None of the molecular variables considered had a significant impact on either overall survival or on death with disease.
assistant
There are insufficient data to justify using molecular genetic changes in primary colorectal carcinomas as prognostic markers. Micrometastases do not provide prognostic information on survival. There is value in increasing the numbers of lymph nodes removed and analysed along with the primary tumour. Final Decision: no