Clinico-pathological patterns and survival outcome of colorectal cancer in young patients: western Saudi Arabia experience

Analysing 11 years of incidence trends, clinicopathological characteristics, and forecasts of colorectal cancer in young and old patients: a retrospective cross-sectional study in an Indonesian national referral hospital

OBJECTIVE

To obtain annual incidence trends, understand clinicopathological characteristics, and forecast the future burden of colorectal cancer (CRC) in Indonesia.

DESIGN

11-year retrospective cross-sectional study.

SETTING

A national referral hospital in Jakarta, Indonesia.

PARTICIPANTS

Data from 1584 eligible cases were recorded for trends and forecasting analyses; 433 samples were analysed to determine clinicopathological differences between young (<50 years) and old (≥50 years) patients.

METHODS

Trend analyses were done using Joinpoint software, expressed in annual percentage change (APC), and a regression analysis was executed to generate a forecasting model. Patients' characteristics were compared using χ2 or non-parametric tests.

MAIN OUTCOMES

Analysis of trends, forecasting model, and clinicopathological features between the age groups.

RESULTS

A significant increase in APC was observed among old patients (+2.38%) for CRC cases. Colon cancer increased remarkably (+9.24%) among young patients; rectal cancer trends were either stable or declining. The trend for right-sided CRC increased in the general population (+6.52%) and old patients (+6.57%), while the trend for left-sided CRC was stable. These cases are expected to be a significant health burden within the next 10 years. Patients had a mean age of 53.17±13.94, 38.1% were young, and the sex ratio was 1.21. Prominent characteristics were left-sided CRC, tumour size ≥5 cm, exophytic growth, adenocarcinoma, histologically low grade, pT3, pN0, inadequately dissected lymph nodes (LNs), LN ratio <0.05, no distant metastasis, early-stage cancer, no lymphovascular invasion, and no perineural invasion (PNI). Distinct features between young and old patients were found in the histological subtype, number of dissected LN, and PNI of the tumour.

CONCLUSIONS

Epidemiological trends and forecasting analyses of CRC cases in Indonesian patients showed an enormous increase in colon cancer in young patients, a particularly concerning trend. Additionally, young patients exhibited particular clinicopathological characteristics that contributed to disease severity.

Clinicopathological Characteristics and Overall 5-Year Survival of Colorectal Cancer: A Retrospective Study

Colorectal cancer (CRC) is the third leading cause of cancer-related death. We aimed to investigate the clinicopathological characteristics and 5-year survival in CRC. This retrospective study reviewed King Abdulaziz University Hospital records from 2009 to 2019. Tumor staging was performed using Dukes’ pathological classification. Additionally, we measured the frequency of qualitative data and performed the chi-square and Mann−Whitney U-tests. Kaplan−Meier analysis was performed to calculate overall survival. Of the 574 included patients (age (mean ± standard deviation), 55.51 ± 14.28 years), 43.2% were Saudis, and most were male (58.7%). The rectum was the most common location of CRC (30.8%); 33.1% of patients presented with abdominal pain. The dominant histological variant was mucinous adenocarcinoma (95.5%). Age at diagnosis was significantly associated with Dukes’ staging; 36.3% of individuals aged <50 years had Dukes’ D stage. The 5-year survival rate was 47.9%. Better survival was noted for those of Saudi nationality, those with Dukes’ A stage, and those who were overweight (51.6%, 56.3%, and 46.8%, respectively). Significantly better survival was seen in Saudi patients due to accessible healthcare and in overweight patients due to better treatment tolerance. The outcome of CRC was not related to sex or metformin use in patients with diabetes mellitus.

A Systematic Review and Meta-analysis on the Occurrence of Biomarker Mutation in Colorectal Cancer among the Asian Population

Globally, colorectal carcinoma (CRC) is the third most common cancer and the third major cause of cancer-related death in both sexes. KRAS and BRAF mutations are almost mutually exclusively involved in the pathogenesis of CRC. Both are major culprits in treatment failure and poor prognosis for CRC. Method. A systematic review and meta-analysis of various research was done following the Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) guidelines. This trial is registered with PROSPERO CRD42021256452. The initial search included 646 articles; after the removal of noneligible studies, a total of 88 studies was finally selected. Data analysis was carried out using OpenMeta Analyst and Comprehensive Meta-Analysis 3.0 (CMA 3.0) software to investigate the prevalence of KRAS and BRAF mutations among patients with CRC in Asia. Results. The meta-analysis comprises of 25,525 sample sizes from Asia with most being male 15,743/25525 (61.7%). Overall prevalence of KRAS mutations was (59/88) 36.3% (95% CI: 34.5-38.2) with I² = 85.54% (P value < 0.001). In 43/59 studies, frequency of KRAS mutations was majorly in codon 12 (76.6% (95% CI: 74.2–78.0)) and less in codon 13 (21.0% (95% CI: 19.1-23.0)). Overall prevalence of BRAF mutations was 5.6% (95% CI: 3.9-8.0) with I² = 94.00% (P value < 0.001). When stratified according to location, a higher prevalence was observed in Indonesia (71.8%) while Pakistan has the lowest (13.5%). Conclusion. Total prevalence of KRAS and BRAF mutations in CRC was 36.6% and 5.6%, respectively, and the results conformed with several published studies on KRAS and BRAF mutations.

9-ING-41, a Small Molecule Inhibitor of GSK-3β, Potentiates the Effects of Chemotherapy on Colorectal Cancer Cells

Colorectal cancer (CRC) is one of the most common and lethal types of cancer. Although researchers have made significant efforts to study the mechanisms underlying CRC drug resistance, our knowledge of this disease is still limited, and novel therapies are in high demand. It is urgent to find new targeted therapy considering limited chemotherapy options. KRAS mutations are the most frequent molecular alterations in CRC. However, there are no approved K-Ras targeted therapies for these tumors yet. GSK-3β is demonstrated to be a critically important kinase for the survival and proliferation of K-Ras–dependent pancreatic cancer cells. In this study, we tested combinations of standard-of-care therapy and 9-ING-41, a small molecule inhibitor of GSK-3β, in CRC cell lines and patient-derived tumor organoid models of CRC. We demonstrate that 9-ING-41 inhibits the growth of CRC cells via a distinct from chemotherapy mechanism of action. Although molecular biomarkers of 9-ING-41 efficacy are yet to be identified, the addition of 9-ING-41 to the standard-of-care drugs 5-FU and oxaliplatin could significantly enhance growth inhibition in certain CRC cells. The results of the transcriptomic analysis support our findings of cell cycle arrest and DNA repair deficiency in 9-ING-41–treated CRC cells. Notably, we find substantial similarity in the changes of the transcriptomic profile after inhibition of GSK-3β and suppression of STK33, another critically important kinase for K-Ras–dependent cells, which could be an interesting point for future research. Overall, the results of this study provide a rationale for the further investigation of GSK-3 inhibitors in combination with standard-of-care treatment of CRC.

Colorectal cancer survival among Ministry of National Guard-Health Affairs (MNG-HA) population 2009-2017: retrospective study

Background

Colorectal cancer (CRC) is the most diagnosed cancer among males and third among females in Saudi Arabia, with up to two-third diagnosed at advanced stage. The objective of our study was to estimate CRC survival and determine prognostic factors.

Methods

Ministry of National Guard- Health Affairs (MNG-HA) registry data was utilized to identify patients diagnosed with CRC between 2009 and 2017. Cases were followed until December 30th, 2017 to assess their one-, three-, and five-year CRC-specific survivals. Kaplan-Meier method and Cox proportional hazard models were used to assess survival from CRC.

Results

A total of 1012 CRC patients were diagnosed during 2009–2017. Nearly, one-fourth of the patients presented with rectal tumor, 42.89% with left colon and 33.41% of the cases were diagnosed at distant metastasis stage. The overall one-, three-, and five-year survival were 83, 65 and 52.0%, respectively. The five-year survival was 79.85% for localized stage, 63.25% for regional stage and 20.31% for distant metastasis. Multivariate analyses showed that age, diagnosis period, stage, nationality, basis of diagnosis, morphology and location of tumor were associated with survival.

Conclusions

Findings reveal poor survival compared to Surveillance, Epidemiology, and End Results (SEER) population. Diagnoses at late stage and no surgical and/or perioperative chemotherapy were associated with increased risk of death. Population-based screening in this population should be considered.

Prognostic Implication of Metastatic Lymph Node Ratio in Colorectal Cancers: Comparison Depending on Tumor Location

Background: The proportion of the number of involved lymph nodes (LNs) to the number of examined LNs—defined as metastatic LN ratio (mLNR)—has been considered as a prognostic parameter. This study aims to elucidate the prognostic implication of the mLNR in colorectal cancer (CRC) according to the tumor location. Methods: We evaluated the correlation between prognoses and the involved and examined LNs as well as mLNR according to the tumor location in 266 surgically resected human CRCs. Besides, to evaluate the optimal cutoff for high and low mLNRs, we investigated the correlation between mLNR and survival according to the various cutoffs. Results: LN metastasis was found in 146 cases (54.9%), and colon and rectal cancers were found in 116 (79.5%) and 30 (20.5%) of the cases, respectively. The mean mLNRs were significantly higher in rectal cancer than in colon cancer (0.38 ± 0.28 vs. 0.21 ± 0.24, P = 0.003). Besides this, the number of involved LNs in rectal cancer was significantly high compared to colon cancer (11.83 ± 10.92 vs. 6.37 ± 7.78, P = 0.014). However, there was no significant difference in the examined LNs between the rectal and colon cancers (31.90 ± 12.28 vs. 36.60 ± 18.11, P = 0.181). In colon cancer, a high mLNR was significantly correlated with worse survival for all cutoffs (0.1, 0.2, 0.3, and 0.4). However, rectal cancer only showed a significant correlation between high mLNR and worse survival in the subgroup with a cutoff of 0.2. Conclusions: Our results showed that high mLNR was significantly correlated with worse survival. The number of involved LNs and mLNRs were significantly higher in rectal cancer than in colon cancer. The cutoff of 0.2 can be useful for the differentiation of prognostic groups, regardless of tumor location.

Metastatic Lymph Node Ratio (mLNR) is a Useful Parameter in the Prognosis of Colorectal Cancer; A Meta-Analysis for the Prognostic Role of mLNR

Background and objectives: The presenting study aimed to elucidate the prognostic role of the metastatic lymph node ratio (mLNR) in patients with colorectal cancer (CRC), using a meta-analysis. Materials and Methods: Using data from 90,274 patients from 14 eligible studies, we performed a meta-analysis for the correlation between mLNR and survival rate. Besides, subgroup analyses were performed, based on tumor stage, tumor location, and mLNR. Results: A high mLNR showed significant correlation with worse overall survival and disease-free survival rates in CRC patients (hazard ratio (HR), 1.617, 95% confidence interval (CI) 1.393-1.877, and HR 2.345, 95% CI 1.879-2.926, respectively). In patients with stage III, who had regional LN metastasis, the HRs were 1.730 (95% CI 1.266-2.362) and 2.451 (95% CI 1.719-3.494) for overall and disease-free survival, respectively. According to tumor location, rectal cancer showed a worse survival rate when compared to colon cancer. In the analysis for overall survival, when mLNR was 0.2, HR was the highest across the different subgroups (HR 5.040, 95% CI 1.780-14.270). However, in the analysis for disease-free survival, the subgroup with an mLNR < 0.2 had a higher HR than the other subgroups (HR 2.878, 95% CI 1.401-5.912). Conclusions: The mLNR may be a useful prognostic factor for patients with CRC, regardless of the tumor stage or tumor location. Further studies are necessary for the detailed criteria of mLNR before its application in daily practice.

Colonic Mucosal Microbiota in Colorectal Cancer: A Single-Center Metagenomic Study in Saudi Arabia

Background and Aim

Because genetic and geographic variations in intestinal microbiota are known to exist, the focus of this study was to establish an estimation of microbiota in colorectal cancer (CRC) patients in Saudi Arabia by means of metagenomic studies.

Methods

From July 2010 to November 2012, colorectal cancer patients attending our hospital were enrolled for the metagenomic studies. All underwent clinical, endoscopic, and histological assessment. Mucosal microbiota samples were collected from each patient by jet-flushing colonic mucosa with distilled water at unified segments of the colon, followed by aspiration, during colonoscopy. Total purified dsDNA was extracted and quantified prior to metagenomic sequencing using an Illumina platform. Satisfactory DNA samples (n = 29) were subjected to metagenomics studies, followed by comprehensive comparative phylogenetic analysis. An equal number of healthy age-matched controls were also examined for colonic mucosal microbiota.

Results

Metagenomics data on 29 patients (14 females) in the age range 38-77 years were analyzed. The majority 11 (37%) of our patients were overweight (BMI = 25-30). Rectal bleeding was the presenting symptom in 18/29 (62%), while symptomatic anemia was the presenting symptom in 11/29 (37%). The location of colon cancer was rectal in 14 (48%), while cecal growth was observed in 8 (27%). Hepatic flexure growth was found in 1 (3%), descending colonic growth was found in 2 (6%), and 4 (13%) patients had transverse colon growth. The metagenomics analysis was carried out, and a total of 3.58G reads were sequenced, and about 321.91G data were used in the analysis. This study identified 11 genera specific to colorectal cancer patients when compared to genera in the control group. Bacteroides fragilis and Fusobacterium were found to be significantly prevalent in the carcinoma group when compared to the control group.

Conclusion

The current study has given an insight into the microbiota of colorectal cancer patients in Saudi Arabia and has identified various genera significantly present in these patients when compared to those of the control group.

The impact of young age on the prognosis for colorectal cancer: a population-based study in Taiwan

Background

The impact of age as a prognostic factor for patients with colorectal cancer (CRC) remains controversial, possibly due to heterogeneity between studies in terms of patient numbers, percentage of patients undergoing curative resection, percentage of patients receiving neoadjuvant therapy, or failure to adjust for potential confounding factors. This study used colorectal cancer survival data from the Taiwan Cancer Registry database in order to comprehensively analyze age as a prognostic factor.

Methods

Survival data were analyzed for 62 060 CRC patients diagnosed with adenocarcinoma, mucinous adenocarcinoma, or signet-ring cell carcinoma of the colon and rectum between 1998 and 2005. The rates of all-cause mortality and CRC-related mortality were determined using Kaplan-Meier analysis, and the log-rank test was used to compare differences in survival between different age groups. The crude and adjusted hazard ratios for all-cause and CRC-related mortalities were calculated according to the estimates from the univariable and multivariable Cox proportional hazard models.

Results

Patients in the ≤40 and the 41-50 age groups had a higher proportion of mucinous adenocarcinoma (P < 0.001) and signet-ring cell carcinoma (P < 0.001) compared to the older age groups. After adjusting for gender, histology, and tumor site, patients in the ≤40 age group had a poorer overall survival (OS) and cancer-specific survival compared to patients in the 41-50 and 51-60, and 61-70 age groups (P < 0.001), but a better OS and cancer-specific survival compared to patients in the 71-80 and >80 age groups (P < 0.001).

Conclusions

Our study indicated that age is an important consideration while determining the clinical management of CRC patients.

State of Art of Cancer Pharmacogenomics in Latin American Populations

Over the past decades, several studies have shown that tumor-related somatic and germline alterations predicts tumor prognosis, drug response and toxicity. Latin American populations present a vast geno-phenotypic diversity due to the great interethnic and interracial mixing. This genetic flow leads to the appearance of complex characteristics that allow individuals to adapt to endemic environments, such as high altitude or extreme tropical weather. These genetic changes, most of them subtle and unexplored, could establish a mutational profile to develop new pharmacogenomic therapies specific for Latin American populations. In this review, we present the current status of research on somatic and germline alterations in Latin America compared to those found in Caucasian and Asian populations.

Policy of screening for colorectal cancer in Saudi Arabia: A prospective analysis

Colorectal cancer (CRC) is one of the most common cancers worldwide. Several policies of CRC screening are available in different countries. The idea of screening is to identify patients at risk by detection of precancerous and small cancers early enough before they become advanced. In Saudi Arabia (SA), there is no countrywide policy for CRC screening despite the increasing incidence of the disease. Screening for CRC is a multidisciplinary approach that requires education programs, substantial financial support, several logistic measures, and predetermined resources before implementing such a program. We performed a prospective and systematic analysis of the of the screening policy of CRC in SA in view of high demand, anticipated development, and implementation of such a policy in the near future. We also attempted to investigate the justification for developing such a policy, as well as the difficulties, barriers, and opportunities that may be faced in its implementation. Further, we highlighted the current view of similar international screening policies. In this analysis, we adopted the framework for health policy analysis that examines four areas which may affect policy development, namely; content, context, process and actors.

Prognostic classification index in Iranian colorectal cancer patients: Survival tree analysis

Aims:

The aim of this study was to determine the prognostic index for separating homogenous subgroups in colorectal cancer (CRC) patients based on clinicopathological characteristics using survival tree analysis.

Methods:

The current study was conducted at the Research Center of Gastroenterology and Liver Disease, Shahid Beheshti Medical University in Tehran, between January 2004 and January 2009. A total of 739 patients who already have been diagnosed with CRC based on pathologic report were enrolled. The data included demographic and clinical-pathological characteristic of patients. Tree-structured survival analysis based on a recursive partitioning algorithm was implemented to evaluate prognostic factors. The probability curves were calculated according to the Kaplan-Meier method, and the hazard ratio was estimated as an interest effect size.

Result:

There were 526 males (71.2%) of these patients. The mean survival time (from diagnosis time) was 42.46± (3.4). Survival tree identified three variables as main prognostic factors and based on their four prognostic subgroups was constructed. The log-rank test showed good separation of survival curves. Patients with Stage I-IIIA and treated with surgery as the first treatment showed low risk (median = 34 months) whereas patients with stage IIIB, IV, and more than 68 years have the worse survival outcome (median = 9.5 months).

Conclusion:

Constructing the prognostic classification index via survival tree can aid the researchers to assess interaction between clinical variables and determining the cumulative effect of these variables on survival outcome.

Increasing Incidence of Colorectal Cancer, Starting at a Younger Age for Rectal Compared to Colon Cancer in Brunei Darussalam

BACKGROUND

Colorectal cancer (CRC) is the most common gastrointestinal malignancy and is a significant cause of mortality. Its incidence is generally increasing in Asia. Reports from the West have indicated that the incidence of rectal cancer is increasing in the younger population. This study assessed the time trend of CRC in Brunei Darussalam specifically assessing the different age groups at which the incidences start to increase.

MATERIALS AND METHODS

The National Cancer registry was reviewed (1991 to 2014). The age standardized rate (ASR) and the age specific incidence rates (ASIRs) for three time periods (1991-1998), (1999-2006) and (2007-2014) were calculated.

RESULTS

The mean age of diagnosis was 59.3±14.6 years old, incidences being slightly higher amongst men (57.6%) and Malays (67.1%). The most common tumor type was adenocarcinoma (96.4%). Rectal cancers accounted for 35.2% (n=372/1,056) of all cancers of the large bowel; more men were affected than women. The proportion of rectal cancer was also high among the indigenous group. In the three time periods, the ASR for CRC increased from 16 per 100,000 (1991-1998) to 19.6 per 100,000 (1999-2006) and 24.3 per 100,000 (2007-2014). The ASIRs for CRC increased markedly between the time periods 1998-2006 and 2007-2014, beginning in the 40-44 years age group. For rectal cancers, the ASIRs started to increase in the 25-29 age group onward whereas for colon cancers, the increase was observed at a later age, starting from the 45-49 age group.

CONCLUSIONS

Our study showed an increase in the incidence of CRC including in the younger age groups. The increase was seen earlier in rectal cancer compared to colon cancer. These data mirror the trends reported from the West.

Relationships of colorectal cancer with dietary factors and public health indicators: an ecological study

BACKGROUND

Colorectal cancer (CRC) is the third most common cancer in Iranian women and fifth in men. The aims of this study were to investigate the relation of dietary factors and public health indicators to its development.

MATERIALS AND METHODS

The required information (2001-2006) about risk factors was obtained from the Non- Communicable Disease Surveillance Centre (NCDSC) of Iran. Risk factor data (RFD) from 89,404 individuals (15-64 years old) were gathered by questionnaire and laboratory examinations through a cross sectional study in all provinces by systematic clustering sampling method. CRC incidence segregated by age and gender was obtained from Cancer Registry Ministry of Health (CRMH) of Iran. First, correlation coefficients were used for data analysis and then multiple regression analysis was performed to control for confounding factors.

RESULTS

Colorectal cancer incidence showed a positive relationship with diabetes mellitus, hypertension, lacking or low physical activity, high education, high intake of dairy products, and non-consumption of vegetables and fruits.

CONCLUSIONS

We concluded that many dietary factors and public health indicators have positive relationships with CRC and might therefore be targets of preliminary prevention. However, since this is an ecological study limited by potential ecological fallacy the results must be interpreted with caution.

Prognostic factors and the role of adjuvant chemotherapy in post-curative surgery for Dukes B and C colon cancers and survival outcomes: a Malaysian experience

BACKGROUND

Adjuvant chemotherapy improves survival in Dukes C colon cancers post-curative resection. However, the evidence for a role with Dukes B lesions remains unproven despite frequent use for disease characterized by poor prognostic features. In view of limited Asia-specific data, this study aimed to determine survival outcomes and identify prognostic factors in a tertiary teaching hospital in Malaysia.

MATERIALS AND METHODS

A total of 116 subjects who underwent curative surgery with and without adjuvant chemotherapy for Duke B and C primary colon adenocarcinomas diagnosed from 2004-2009 were recruited and data were collected retrospectively. Five-year overall survival (OS) and disease free survival (DFS) were analysed using Kaplan-Meier survival analysis and log-rank (Mantel-Cox) test. Prognostic factors were determined using Cox proportional hazards regression with both univariate and multivariate analyses.

RESULTS

The survival analysis demonstrated a 5-year OS of 74.0% for all patients, with 74.9% for Dukes C subjects receiving chemotherapy compared to 28.6% in those not receiving chemotherapy (p=0.001). For Dukes B disease, the 5-year survival rate was 82.6% compared to 75.0% for subjects receiving and not receiving chemotherapy, respectively (p=0.17). Independent prognostic factors identified included a CEA level more than 3.5 ng/ml (hazard ratio (HR)=4.78; p=0.008), serosal involvement (HR=3.75; p=0.028) and completion of chemotherapy (HR= 0.20; p=0.007).

CONCLUSIONS

In a regional context, this study supports current evidence from the West that adjuvant chemotherapy improves survival in Dukes C colon cancers post curative surgery. However, although a clear benefit has yet to be proven for Dukes B disease, our results suggest survival improvement in selected cases.

Frequent BRAF mutation in early-onset colorectal cancer in Taiwan: association with distinct clinicopathological and molecular features and poor clinical outcome

BACKGROUND

Occurrence of early-onset colorectal cancer (EOCRC) under the age of 30 is very rare and the molecular characteristics are poorly understood. A low BRAF mutation rate has been noted in several studies of EOCRC from Western countries.

AIMS

To determine the clinicopathological and molecular features of EOCRCs in Taiwan.

METHODS

KRAS/BRAF gene mutation, mismatch repair protein immunohistochemistry, microsatellite instability and CpG island methylation phenotype analyses were examined to determine the molecular characteristics of EOCRC.

RESULTS

Sixty-six patients with EOCRC at our hospital between 2000 and 2012 were studied. BRAF mutation was detected in 11 of the 59 tumours analysed (19%) and the rate was significantly higher than the overall BRAF mutation rate of colorectal cancer in patients older than 30 years (p<0.001). Clinically, 9 of 11 patients with BRAF-mutated tumours presented with advanced-stage diseases and they presented significantly more frequently with stage IV disease than those with BRAF wild-type tumours (p=0.042). Histologically, BRAF mutation was associated with a poorly differentiated histology, a serrated precursor polyp and focal signet ring cell differentiation (p=0.042, 0.008 and 0.008, respectively). None of the BRAF-mutated tumours was mismatch repair protein-deficient and/or microsatellite instability-high. Overall survival of patients with BRAF-mutated tumours was significantly worse than that of patients with BRAF wild-type tumours, despite adjustment for the disease stages and tumour differentiation.

CONCLUSIONS

BRAF mutation was frequent in EOCRCs in Taiwan and was associated with distinct clinicopathological and molecular features.

High rate of advanced colorectal polyps in a 10-year-long retrospective study in Qazvin, Iran

BACKGROUND

Polyps are common lesions in the gastrointestinal (GI) tract. Colon cancer is mostly a result of progression from polyps. The present study aimed to evaluate demographic, clinical, and histological characteristics of colorectal polyps in Iran, particularly neoplastic and advanced types.

MATERIALS AND METHODS

Over a period of 10 years, specimens of all colorectal polyps obtained from colonoscopy were studied. The variables subjected to statistical analysis were age, sex, and the chief clinical complaint of the patients who underwent colonoscopy, their motivation, and the site, size, and histological types of detected polyps. The level of significance was set at p value<0.05.

RESULTS

Data were obtained from a total of 352 patients. No difference was seen between male and female patients regarding histological types. Only in nine patients was screening the reason for colonoscopy. Almost two-thirds (66.2%) of the polyps were neoplastic. Familial polyposis syndrome and inflammatory bowel disease were seen in 4.3% and 3.0% of the patients with neoplastic polyps, respectively. Sites of polyps were the sigmoid, rectum, and descending colon in 40.1%, 34.5%, and 17% of the cases, respectively. The advanced type made up 58.8% of neoplastic polyps. Only 3.6% of the patients undergoing colonoscopy in the study period had biopsied polyps.

DISCUSSION

No difference was observed between male and female patients in terms of overall incidence of polyps, histological and anatomical profiles, and mean age distribution. Anatomical and histological profiles agreed with the studies performed in areas with a low risk of colon cancer. The findings show that colonoscopy was not performed when it was necessary. A meaningful increase in the number polyp biopsy cases and a corresponding decrease in polyp size in the last few years of the study can be associated with the presence of more GI specialist clinicians in hospital centers, and this holds out much hope for the further improvement of the situation in the future.

Global impact of KRAS mutation patterns in FOLFOX treated metastatic colorectal cancer

Background: Colorectal cancer (CRC) is one of the most frequent events in oncology. Advances in molecular understanding of the processes of carcinogenesis have shed light on the fundamental mechanisms of tumorigenesis. Currently, knowledge of the molecular basis of its pathogenesis is being used to improve patient care and devise more rational therapeutics. Still, the role played by the mutation patterns of mutated genes in the clinical outcomes that patients on pharmacological treatment receive remains unclear. In this study, we propose to analyze the different clinical outcomes and disease prognosis of patients with stage IV CRC treated with FOLFOX chemotherapy (fluorouracil, leucovorin, oxaliplatin) based on different Kirsten ras (KRAS) mutation patterns.

Methods: In this cohort study, 148 patients diagnosed with stage IV CRC and treated with FOLFOX were studied between 2008 and 2013. Mutational status of KRAS was determined. Progression-free survival (PFS) and overall survival (OS) were measured, and all deaths were verified. Survival analysis was performed using Kaplan–Meier analysis, comparison among groups was analyzed using the log-rank test, and multivariate analysis was conducted using Cox proportional-hazards regression.

Results: Among a total of 148 patients, 48 (32%) had mutated KRAS, 77% at codon 12 and 23% at codon 13. The PFS was significantly worse in the mutant KRAS patients in comparison to wild type KRAS patients (p < 0.05). The OS did not show significant differences between the two groups. Multivariate analysis showed KRAS mutation as an independent negative prognostic factor for PFS. Among the various subtypes of KRAS mutation, G12D was significantly associated with a poor prognosis in PFS (p = 0.02).

Conclusion: In our population, the KRAS mutation had an adverse impact on the prognosis for stage IV CRC patients treated with the FOLFOX regimen.

Five-year outcomes of preoperative chemoradiation for rectal carcinoma in Saudi population: single-institutional experience

OBJECTIVES

Preoperative chemoradiation (CRT) followed by surgery is the standard treatment for locally advanced rectal cancer (LARC). The outcomes of preoperative CRT in Saudi patients with LARC have not been widely studied. The study reports long-term outcomes after preoperative CRT followed by curative surgery in Saudi patients with LARC.

DESIGN AND SETTINGS

A retrospective, single-institutional study performed in the tertiary care oncology center in Saudi Arabia.

MATERIALS AND METHODS

A total of 154 out of 204 patients with LARC were treated with preoperative CRT and followed by surgery at the oncology center between September 2005 and November 2012. Data regarding the response rates, toxicity profile, locoregional control (LRC), distant metastasis control (DMC), overall survival (OS), and disease-free survival (DFS) rates were analyzed.

RESULTS

The median age of the study population was 56.6 years (range: 26-89). Predominant clinical stages were IIA (70 patients; 45.4%) and IIIB (49 patients; 31.8%). Majority of patients (79.8%) underwent a complete total mesorectal excision (TME). Complete pathological response (ypT0N0) was seen in 26 patients (16.8%). At 5 years, locoregional recurrence (LR) was reported in 12 patients (7.8%), and distant metastases were noted in 33 patients (21.4%). The 5-year cumulative LRC, DMC, OS, and DFS rates were 91%, 71.3%, 78%, and 64.8%, respectively. Stage, nodal status, circumferential margins, ypT0N0, and adjuvant chemotherapy were found to be important prognostic factors for DFS.

CONCLUSION

The results of preoperative CRT followed by surgery and adjuvant chemotherapy in Saudi population are comparable with international data.