Authors: Bassim Jaffar Al Bahrani, Itrat Mehdi, Essam Abdul Monem, AbdulAziz Majid Al Farsi, Najla Al Lawati, Ayman Mohammed Nada.
Introduction: Colorectal cancer (CRC) is the first most predominant malignancy in men, a bit less 3rd commonest in women. The prevalence rate is higher in developed than in developing economies, though the pattern is gradually changing. In Oman, CRC prevalence rate has shown a significant escalating pattern in the recent past. From 1996 to 2012, CRC incidence in Oman has increased by 282% in females and 386% in males. There is emerging data that
right and left sided lesions are different in terms of aetiology, pathogenesis, biologic behaviour, genetic makeup, response to treatment and outcome. This study has looked at this issue in the Omani population of CRC.
Methods: Eligible CRC patients treated at the Royal Hospital were identified from electronic medical record (Al-SHIFA 3) and Oman cancer registry data base (Ministry of Health) from 1998-2013. The BMI (body mass index), age, gender, stage, tumour location, K-Ras status, and Diabetes mellitus (DM) were explored. The RAS mutation status test (mutant type MT or wild type WT) was carried out in Lab21. Log regression was conducted to estimate the association between food intake, BMI, presence of metabolic syndrome, and level of physical activity with both cancers. Data was analysed using the SPSS.
Results: Total number of patients treated at Royal Hospital were 492, 193 females (44%) and 214 males (56%). About 71.9% of patients were less than 60 years of age. The obese and overweight patients were 201 (57.3%). The rectum was found to be the predominant site of the tumor. The left sided tumors were significantly higher, 4 out of every 5 tumors (80.3% Vs 16.4%). The patients with right sided CRC were slightly younger, had a higher BMI, and more likely to be diabetic. The tumors of the left colon are more K-ras wild while those of the right colon are more K-ras mutant.
Conclusions and Discussion: The right sided tumors as per our study are younger; with significant obesity, diabetes, and K-Ras mutant, and this correlates with high meat and protein consumption in the Omani population. The sidedness or laterality of CRC needs further study in Oman. There is emerging data that right and left-sided lesions are different in terms of etiology, pathogenesis, biologic behaviour, genetic makeup, response to treatment and outcome.
View/Download pdf