Available data on incidence of K- RAS mutation is scarce in Asian region, we in the department of medical oncology at Army Hospital Research and Referral,New Delhi conducted a hospital based study to know presence of K–RAS mutational status in Indian patients diagnosed with metastatic colorectal cancer.
1 To assess incidence of K-RAS gene mutation in the setting of metastatic colorectal cancer in patients of Indian population.
2 To find co-relation of K-RAS mutation with demographic and various clinical parameters in same patient population.
This was a prospective as well as retrospective, nonrandomized single arm study . It was done over a period of 4 years from Nov 2009- Jan 2013 (2 years prospective and 2 years retrospective).The study protocol was reviewed and duly permitted by the Institutional Scientific and Ethics committees.The DNA PCR and Sanger chain-termination method was used as diagnostic method for detecting K-RAS mutation. Data analysis was done using SPSS, version 11.5.
Age of the patients ranged from 15-87 years with mean age of 58.4 years. Overall incidence of K-RAS oncogene mutation identified in 146 colorectal carcinoma cases was 22.6% (33/146 cases). Codon 12 was mutated in 78.8% cases where as codon 13 was mutated in 21.2% cases respectively.There was no association of K-RAS mutation with age, sex, gender, regional distribution, tumor location, tumor differentiation, tumor histology, levels of CEA, presentation as acute abdomen and presence of liver or lung metastasis.
1 The rate of K-RAS mutation in Indian population was seen in lower frequency than reported in western population but close to rates reported in neighboring Asian and Middle Eastern population.
2 No significant association of K-RAS mutation was found with demographic characters and clinical factors. Similar results have been reported in most of the studies done in Asian and Eastern population.