Survival Outcomes of Metastatic Colorectal Cancer Patients in Brunei Darussalam and the Impact of KRAS Mutations
Colorectal cancer (CRC) is the third most common cancer, with rising incidence due to lifestyle and diet. 40% of CRC cases are found to have KRAS mutations. In this study, we investigate the survival outcome of metastatic Colorectal cancer mCRC) patients in Brunei Darussalam restrospectively. Chi-squared test was used to compare the survival outcomes of mCRC patients, and Mann-Whitney U test was used to compare the median ages of both groups. Kaplan-Meier survival curves were drawn and logrank
... drawn and logrank test was used to compare the survival outcome between two groups. There was a total of 105 patients with stage IV CRC being treated during the study period. 81.6% (n=62) of mCRC patients were found to have the primary tumours on the left side of the colon. 19 of these 26 (73.1%) mutant KRAS mCRC patients died, while 23 of 50 (46.0%) wild-type KRAS mCRC patients died at the end of the study period, contributing to death rates of 45.2% and 54.8%, correspondingly. 30.3% (n=23) of the study population had a single metastatic site detected (either liver, or lung or any other organs), while 69.7% (n=53) of the 76 mCRC patients had two (double) or more metastatic sites. 69.2% (n=18) and 30.8% (n=8) of the mutant KRAS mCRC patients had mutations within codons 12 and 13, respectively. To our knowledge, this is the first study in Brunei Darussalam to analyse both the survival outcomes of metastatic CRC patients and those of mutant KRAS mCRC patients. Chi-squared analysis showed a significant difference between the survival outcomes of wild-type KRAS and mutant KRAS mCRC patients (p-value = 0.024). There was a significant difference in the survival outcome between the mutant KRAS mCRC patients with RCC and mutant KRAS mCRC with LCC patients. There was no significant difference between the survival outcomes of mutant KRAS patients with mutations in either codon 12 or 13 of the KRAS gene (Table 3). However, there is a significant difference in the median survival periods between the mutant KRAS mCRC patients with mutations in codon 12 and those with mutation in codon 13 of the KRAS gene (p-value = 0.003). In conclusion, we found that mutant KRAS mCRC patients had a significantly poorer OS, which was shown to be worse when the primary tumours were found at the left side of the colon. Mutant KRAS mCRC patients with mutations in codon 12 were found to have shorter survival median periods than those with mutations within codon 13.