Studies On Hereditary Colorectal Cancers: Experience From A Rural Cancer Center- Kalish Cancer Hospital & Research Center In Western India.

Background: Colorectal cancer (CRC) is the fourth most common cancer in men and third most common cancer in women worldwide, with higher incidence reported in western countries. Over the last decade a remarkable 2-4 fold increase in CRC incidence has been observed in Asian countries like India. Lower prevalence of sporadic CRC cases in India have been linked to lifestyle, with an emphasis on a vegetarian diet. However, the incidence of hereditary CRCs in India have not been well documented. In the west hereditary CRCs i.e. Familial adenomatous polyposis (FAP) and Lynch syndrome or the Hereditary Nonpolyposis Colon Cancer (HNPCC) are common and account for 1% and 2-5% of the CRCs reported, respectively. We report a similar trend at a rural cancer center in western India (KCHRC, Goraj, Gujarat), where 70-75 CRC patients are seen annually. Methods: We have identified three families, one diagnosed with FAP and two with HNPCC. In order to identify the underlying germline mutation in each family, we sequenced the genomes of 3 families, one with FAP and two with reported HNPCC. Results: In The FAP family, we identified a novel heterozygous mutation in the APC (pSerPhefster6) gene in 3 affected members, all aged above 45 years. The mutation was also found in younger unaffected members of this family who have been appropriately counselled. Both HNPCC families had unique mutations in the MLH1 gene, a frequently mutated gene in HNPCC with a role in DNA mismatch repair. Conclusions: Thus far we have identified mutations in genes frequently reported in the west in both FAP and HNPCC. In FAP the region of mutation is APC but the mutation is unique. Further larger number of patients require to evaluate and compare to western countries. [ABSTRACT FROM AUTHOR]