Kristen Rat Sarcoma Viral Oncogene Mutations in Colorectal Carcinomas at the University Teaching Hospital in Lusaka, Zambia

Abstract

Background: The second leading cause of cancer-related deaths worldwide is colorectal cancer. With an incidence rate of 4.8 per 100,000, this is Zambia’s sixth most prevalent cancer;

Methods: This laboratory-based, cross-sectional study examined the frequency of Kirsten rat sarcoma viral oncogene homolog (KRAS) mutation and its association with prognostic factors in colorectal carcinoma cases from the University Teaching Hospital-Adult Hospital (UTHs), Lusaka, Zambia;

Results: Thirty (30) formalin-fixed paraffin-embedded (FFPE) samples collected between June 2017 and June 2018 were sent to the Lancet laboratories and analyzed for KRAS mutations (codons 12 and 13). One FFPE block did not meet the inclusion criteria and was excluded. The demographic and clinicopathological data were analyzed using STATA 12. Males outnumber females by 20 to nine. The average age of the patient was 45 ± 16 years. The rectum was the location of 44.8% of the tumors, with the majority being conventional adenocarcinoma (CAC) (65.6 %). All cases (100%) had advanced-stage (stages 3 and 4) disease; however, only 27.6% of patient tumors exhibited lymphovascular invasion. KRAS mutation was detected in 11 (37.9%) cases and mainly in left-sided tumors (62.5%). KRAS mutations were only detected in CAC and serrated adenocarcinoma subtypes. No significant associations were observed between the KRAS mutation status and tumor or patient’s clinical and sociodemographic factors; 

Conclusion: We advocate for incorporating KRAS mutation testing into the standard of care for treating colorectal cancer.