Colorectal cancer in iran: molecular epidemiology and screening strategies

Measuring Beliefs Related to Colorectal Cancer Screening Behavior among Iranian Middle-Aged and Elderly: a Psychometric Study

The annual fecal occult blood test is a very important method for colorectal cancer early detection through screening. Our aim was to assess psychometrics of instrument measuring beliefs related to fecal occult blood test uptake among Iranian middle-aged and elderly, based on the theory of planned behavior. This cross-sectional study was performed on 150 middle-aged and elderly who were randomly selected to participate voluntarily in Kermanshah, in the west of Iran. The studied constructs included attitude, subjective norms, perceived behavior control, and behavior intention. Data were analyzed with SPSS software (ver. 21.0). The mean age of the respondents was 59.1 years [SD: 6.73], in the range from 50 to 73. All of the loads of the exploratory factorial analysis were larger than 0.4. KMO was calculated as 0.756. Overall, four factors under investigation accounted for 82% of the variance in the hypothesized model. Cronbach’s alpha for the measured constructs of attitude, subjective norms, perceived behavior control, and behavior intention were 0.92, 0.88, 0.70 and 0.88, respectively. Our findings indicated the final scale to be adequately reliable and valid for measurement of these constructs for prediction of fecal occult blood test uptake among Iranian middle-aged and elderly.

Main Risk Factors Association with Proto-Oncogene Mutations in Colorectal Cancer

Objective: Although several factors have been shown to have etiological roles in colorectal cancer, few investigations have addressed how and to what extent these factors affect the genetics and pathology of the disease. Precise relationships with specific genetic mutations that could alter signaling pathways involved in colorectal cancer remain unknown. We therefore aimed to investigate possible links between lifestyle, dietary habits, and socioeconomic factors and specific mutations that are common in colorectal cancers. Methods: Data were retrieved from a baseline survey of lifestyle factors, dietary behavior, and SES, as well as anthropometric evaluations during a physical examination, for 100 confirmed primary sporadic colorectal cancer patients from Northwest Iran. Results: High socioeconomic status was significantly associated with higher likelihood of a KRAS gene mutation (P < 0.05) (odds ratio: 3.01; 95% CI: 0.69–13.02). Consuming carbohydrates and alcohol, working less, and having a sedentary lifestyle also increased the odds of having a KRAS mutation. Conclusion: Although research has not yet described the exact relationships among genetic mutations with different known risk factors in colorectal cancer, examples of the latter may have an impact on KRAS gene mutations.

Evaluation of immunohistochemical expression of survivin and its correlation with -31G/C gene polymorphism in colorectal cancer

Colorectal cancer (CRC) placed among the most common neoplasm. Survivin is a member of the inhibitor apoptosis gene family. This gene could be associated with aggressive behavior in numerous types of cancers. The aim of the present study was to evaluate the immunohistochemical expression of survivin gene and its correlation with -31G/C polymorphism in CRC patients. This case-control study was performed on 90 cases: 30 adenocarcinoma, 30 adenomatous polyp, and 30 normal colon. Immunohistochemical expression of survivin evaluated on formalin-fixed paraffin-embedded tissue and -31G/C polymorphism was analyzed by polymerase chain reaction-restriction fragment length polymorphism analysis. Results showed that the subjects carrying C/C genotype with 43.3% (p = 0.002' OR = 12.188, CI = 2.530-58.720) and G/C genotype with 43.3% (p = 0.032' OR = 4.432, CI = 1.133-17.341) significantly had increased risk of CRC compared with subjects carrying GG genotype. Allelic frequencies showed statistically significant difference (p = 0.001) among adenocarcinoma (G = 35%, C = 65%), adenomatous (G = 43.3, C = 56.7), and normal group (G = 68.3, C = 31.7). Immunohistological evaluation showed nuclear survivin protein expression in patients with the CC genotype higher than in patient with the GG and GC genotypes (p = 0.002). The results suggest that C allele of - 31G/C polymorphism in survivin might be cooperative in CRC development.

O6-Methyguanine-DNA Methyl Transferase (MGMT) Promoter Methylation in Serum DNA of Iranian Patients with Colorectal Cancer

Introduction:

Colorectal cancer (CRC) is a leading cause of cancer deaths worldwide but current molecular targeted therapy is not providing major success in CRC treatment, so early detection by non-invasive methods continues to be vital. Aberrant methylation of CpG islands in promoter regions is associated with inactivation of various tumor suppressor genes. O6-methyguanine-DNA methyltransferase (MGMT) is a DNA repair enzyme that removes mutagenic and cytotoxic adducts from O6-guanine in DNA. Aberrant hypermethylation of the MGMT promoter has been associated with lack of mRNA expression, with concomitant loss of protein content and enzyme activity.

AIM:

Our aim was to determine whether MGMT promoter methylation might be detectable in circulating free DNA in the serum of CRC patients and normal individuals using a methylation specific (MSP) polymerase chain reaction (PCR) method.

Methods:

A total of 70 subjects were enrolled in the study. Of these, 30 patients who were diagnosed previously as untreated colon adenocarcinoma by a gastroenterologist and the other 40 were nearly age-matched individuals who had a normal colonoscopic evaluation (except for hemorrhoids or fissures) and normal pathologic reports. After bisulphite modification of DNA, serum samples were examined for MGMT promoter methylation using MSP.

Results:

Ninety percent of CRC patients had MGMT promoter hypermethylation as compared to no methylation in normal subjects’ serum. Most of the cancers were stage П and moderately differentiated adenocarcinomas; nearly 60% were found in the left colon. No statistically significant correlation was found between the promoter methylation status and gender and age.

Discussion and Conclusions:

MGMT hypermethylation can be detected in free circulating DNA in serum of CRC patients and can be used “as a clinical biomarker” for early diagnosis and prognostic assessment of the disease. Our data confirm previous studies indicating utility for free circulating DNA as a serum biomarker for early detection, diagnosis and monitoring of CRC patients.

KRAS and NRAS Testing in Metastatic Colorectal Cancer in Central Iran (Tehran): A Review on Literature of the Middle East

Context: The incidence of colorectal cancer (CRC) in the past three decades in Iran has made it as a major public health burden. Aims: The aim of this study is to report the prevalence of KRAS and NRAS mutations in Iran and the correlation between KRAS mutation status with clinicopathological factors and survival.Materials and Methods: In a cross-sectional study, 144 patients were entered into the study based on the criteria. Age, sex, tumor site, grade, metastasis location, familial history, KRAS/NRAS status, and survival were checked for all patients, and the patients were followed for 1 year. DNA was extracted with FFPE QIAGEN kit and then polymerase chain reaction for amplification of gene segments of KRAS and NRAS genes. Results: The mean age at diagnosis was 52.9 years (range: 27–72 years) that 39.6% patients had age <50 years and 54.2% were men. KRAS mutation was significantly more in the patients with age ≥50 compared with KRAS wild type. Furthermore, the 6-month overall survival rate in KRAS mutation patients was significantly more than KRAS wild-type patients. Liver metastasis (72.9%) had the highest prevalence of metastasis in the patients, and Grade II with 64.6% had the most prevalence. Conclusions: The metastatic CRC was more prevalent in men than women, and the mean age varied around 50–60 years. The results showed that the present study had the highest prevalence of KRAS mutation in the Middle East and Pakistan with the lowest prevalence in CRC patients.

Pattern of LRP6 gene expression in tumoral tissues of colorectal cancer

BACKGROUND

Colorectal cancer (CRC) is known as one of the most leading causes of death from cancer in the world. Wnt signaling pathway is the most important signaling pathway activated in this type of cancer. The low-density lipoprotein (LDL) receptor-related protein-6 (LRP6) functions as a co-receptor in order to trigger this signaling pathway.

OBJECTIVE

The expression of LRP6 was studied in cell lines, tumoral and normal adjacent tissues from patients affected with colorectal cancer.

MATERIALS AND METHODS

The expression of LRP6 was assayed by quantitative Real time PCR.

RESULTS

LRP6 is overexpressed at the transcript and protein level in HCT116 and SW480 in comparison to HUVEC as the non-cancerous cell. Furthermore, LRP6 was significantly up-regulated in 61% of human malignant tissues (p-value = 0.0008). In inherited type of disease, this upregulation was lower than other types of colorectal cancer, while in rectal cancer the overexpression was significantly higher (p-value = 0.039). Gene expression was not correlated with the age, gender and the stage of disease.

CONCLUSION

Due to the profound overexpression of LRP6 in sporadic and rectal types of cancer compared to normal colonic ones, antagonist related approaches can be promising for targeted therapies of cancer.

Evaluation of HPV DNA positivity in colorectal cancer patients in Kerman, Southeast Iran

Background:

The HPV virus is known to be oncogenic and associations with many cancers has been proven. Although many studies have been conducted on the possible relationship with colorectal cancer (CRC), a definitive role of the virus has yet to be identified.

Method:

In this cross-sectional study, the frequency of HPV positivity in CRC samples in Kerman was assessed in 84 cases with a mean age of 47.7 ± 12.5 years over two years. Qualitative real time PCR was performed using general primers for the L1 region of HPV DNA.

Results:

Out of 84 CRC samples, 19 (22.6%), proved positive for HPV DNA. Genotyping of positive samples showed all of these to be of high risk HPV type. Prevalence of HPV infection appears to depend geographic region, life style, diet and other factors.

Conclusion:

In our location frequency of CRC is low, and this limited the sample size for evaluation of HPV DNA. The most prevalent types were HPV types 51 and 56. While HPV infection may play an important role in colorectal carcinogenesis, this needs to be assessed in future studies.

Anti-ROR1 scFv-EndoG as a Novel Anti-Cancer Therapeutic Drug

Aim: Immunotoxins are proteins that consist of an antibody fragment linked to a toxin, used as agents for targeted therapy of cancers. Although the most potent immunotoxins are made from bacterial and plant toxins, obstacles which contribute to poor responses are immunogenicity in patients and rapid development of neutralizing antibodies. In the present study we proposed a new therapeutic immunotoxin for targeted cancer therapy of ROR1 expressing cancers: an anti ROR1 single chain fragment variable antibody (scFv)-endonuclease G (anti ROR1 scFv-EndoG). Methods: The three-dimensional structure of anti ROR1 scFv-EndoG protein was modeled and structure validation tools were employed to confirm the accuracy and reliability of the developed model. In addition, stability and integrity of the model were assessed by molecular dynamic (MD) simulation. Results: All results suggested the protein model to be acceptable and of good quality. Conclusions: Anti-ROR1 scFv-EndoG would be expected to bind to the ROR1 extracellular domain by its scFv portion and selectively deliver non-immunogenic human endonuclease G enzyme as an end-stage apoptosis molecule into ROR1-expressing cancer cells and lead rapidly to apoptosis. We believe that anti ROR1 and other anti-tumor antigen scFv-EndoG forms may be helpful for cancer therapy.

Development of a Colorectal Cancer Screening Intervention for Iranian Adults: Appling Intervention Mapping

Background: While the incidence rate of the colorectal cancer (CRC) has been increasing over the last three decades in Iran, very limited interventions to increase CRC screening have been developed for Iranian population. The purpose of this study was to describe the use of Intervention Mapping (IM) for applying theory and evidence and considering local contexts to develop a CRC screening program among adults in Iran. Materials and Methods: From April 2014 to July 2016 following the IM process, six steps were formulated and implemented. First a need assessment was conducted involving relevant stakeholders and using focus groups discussions (n=10), individual interviews (n=20), and a household survey (n= 480). Then a matrix of change objectives was developed for each behavioral outcome and theoretical methods and their practical applications were identified to guide intervention development and implementation. A multi-component intervention was developed and piloted. Decision on suitable parts of intervention was made based on feedback of pilot study. Finally, evaluation plan including process and outcome evaluation was generated and conducted to inform future scale up. Results: The needs assessment highlighted factors affecting CRC screening including knowledge, self efficacy, social support and perceived benefit and barriers (financial problems, fear of detection of cancer and etc). Results of needs assessment were used to develop next steps IM. The program utilized methods like information delivery, modeling, and persuasion. Practical applications included video presentation, group discussion, role playing and postcards.This program was assessed through a cluster-randomized controlled trial. Results showed that there were significant differences in CRC screening uptake between intervention groups and control (P<0.001). Conclusions: IM is a useful process in the design of a theory-based intervention addressing CRC screening among Iranian population.

Long Noncoding RNA PlncRNA-1 Promotes Colorectal Cancer Cell Progression by Regulating the PI3K/Akt Signaling Pathway

Accumulating evidence has indicated that long noncoding RNA (lncRNA) PlncRNA-1 plays an important regulatory role in cancers. However, the expression and biological functions of PlncRNA-1 in colorectal cancer (CRC) are still unclear. In the present study, we determined the expression of PlncRNA-1 in CRC and explored the function of PlncRNA-1 on CRC cell progression. The results showed that PlncRNA-1 was significantly increased in CRC tissues and cell lines; high PlncRNA-1 expression was associated with depth of invasion, lymph node metastasis, and TNM stage of CRC patients. Kaplan–Meier curve analysis showed that patients with high PlncRNA-1 expression had a poor overall survival. PlncRNA-1 knockdown remarkably reduced cell proliferation, migration, and invasion and promoted cell apoptosis in vitro. In vivo xenograft experiments showed that PlncRNA-1 inhibition significantly suppressed tumor growth. Finally, we used an agonist (740Y-P) of the PI3K/Akt signaling pathway; function assays showed that PlncRNA-1 exerted its effects by targeting the PI3K/Akt signaling pathway in CRC. Taken together, our data suggested that PlncRNA-1 might act as an oncogene in CRC progression and serve as a potential biomarker and therapeutic target for the treatment of CRC.

Familial Colorectal Cancer Type X in Central Iran: A New Clinicopathologic Description

Background: Familial colorectal cancer type X (FCCX) is a subtype of mismatch repair (MMR)-proficient colorectal cancerin which the patients are clinically at risk for Lynch syndrome (LS), a common hereditary cancer predisposing syndrome. In this study, we described a new clinicopathological feature of the condition in central Iran. Materials and Methods: We designed a descriptive, retrospective study to screenat-risk colorectal cancer (CRC) patients, using Amsterdam II criteria and Molecular analysis in Isfahan (central Iran) throughout 2000-2013 period. Results: 219 early-onset (≤ 50 years) CRC patients of 1659 were selected for the evaluation. Amsterdam II criteria were positive in 45 families; of whom 31 were finally analyzed by molecular testing. MMR deficiency was detected in 7/31 probands (22.6%) as affected to LS, so 24 families (77.4%) were identified as FCCX. The mean age of the probands at diagnosis among FCCX families was 45.3 years (range 24-69) versus 38.0 years (range 31-50) in LS families. The frequency of CRC among FCCX and LS families was calculated 27.9% and 67.5%, respectively. Also, the most frequent extracolonic cancer among both FCCX and LS families was stomach by 25.5% and 30.8%, respectively. Tumor site was proximal to the splenic flexure in 20.8% and 57.1% of index CRC patients in FCCX and LS families, respectively. Conclusion: Given the relative high frequency of FCCX and its different phenotype among Iranian populations, we need to set up more advanced molecular studies for exploration of unknown molecular pathways leading to tumorigenesis in this class of CRC patients.

Rising rates of colorectal cancer among younger Iranians: is diet to blame?

BACKGROUND

Colorectal cancer (crc) is one of the most prevalent cancers in the world. Although the incidence of crc is currently very low in the older Iranian population compared with Western populations, young Iranians show a rising trend of crc-that is, the age-adjusted rate is close in the young Iranian population compared with the U.S. population, and the rate in older Iranians is much lower.

METHODS

To assess a putative relationship between diet and a rising rate of crc in younger Iranians, a combined text word and mesh heading search strategy identified relevant studies through Google Scholar and medline.

RESULTS

A critical look at diet among Iranians shows major issues that might be raising the risk for crc. There are also scenarios other than diet for the rise, such as the young age structure of the country. However, the actual scenario is more complex.

CONCLUSIONS

In Iran, crc is one of the most common incident cancers and a common cause of cancer death. Primary and secondary prevention-with attention to a healthy lifestyle, physical activity, and screening-should be enhanced in the general population.

Importance of miR-299-5p in colorectal cancer

Background

MicroRNAs (miRNAs) are effective regulators of gene expression that play a pivotal role in the pathogenesis of colorectal cancer (CRC) and various other cancers. The high prevalence of aberrant miRNA expression in CRC suggests that they can be used as biomarkers and anticancer molecules for therapeutic purposes. There is evidence that microRNA-299-5p (miR-299-5p) is associated with vital cell processes (e.g. epithelial-mesenchymal transition, proliferation, and tumorigenicity) and its improper expression with tumorigenesis in many types of human cancer. This prospective study investigated the contribution of miR-299-5p to CRC tumorigenesis.

Methods

The real-time reverse transcription-polymerase chain reaction was used to examine miR-299-5p expression levels prospectively in 40 sample pairs of CRC tissue and adjacent noncancerous tissue (>2 cm from cancer tissue). The ability of miR-299-5p to function as a tumor marker was also examined.

Results

The expression levels of miR-299-5p were significantly downregulated in the group of CRC samples compared with matched noncancerous tissue samples. No significant relationship was found between miR-299-5p expression levels and clinicopathological features. Receiver operating characteristic analysis gave an area under the curve of 71% for miR-299-5p with 68% sensitivity and 78% specificity (P=0.001).

Conclusion

The miRNA miR-299-5p may be considered as a tumor marker in CRC and could be of assistance as a potential predictive biomarker in the diagnosis of this cancer.

New frontiers in the treatment of colorectal cancer: Autophagy and the unfolded protein response as promising targets

Colorectal cancer (CRC), despite numerous therapeutic and screening attempts, still remains a major life-threatening malignancy. CRC etiology entails both genetic and environmental factors. Macroautophagy/autophagy and the unfolded protein response (UPR) are fundamental mechanisms involved in the regulation of cellular responses to environmental and genetic stresses. Both pathways are interconnected and regulate cellular responses to apoptotic stimuli. In this review, we address the epidemiology and risk factors of CRC, including genetic mutations leading to the occurrence of the disease. Next, we discuss mutations of genes related to autophagy and the UPR in CRC. Then, we discuss how autophagy and the UPR are involved in the regulation of CRC and how they associate with obesity and inflammatory responses in CRC. Finally, we provide perspectives for the modulation of autophagy and the UPR as new therapeutic options for CRC treatment.

Evaluation of prognostic factors effect on survival time in patients with colorectal cancer, based on Weibull Competing-Risks Model

AIM

The aim of this study was to assess the association between survival of patients with colorectal cancer and prognostic factors in a competing risk parametric model using Weibull distribution.

BACKGROUND

The prognosis of colorectal cancer is relatively good in terms of survival time. In many prognostic studies, patients may be exposed to several types of competing events. These different causes of death are called competing risks.

METHODS

Data was recorded from 372 patients with colorectal cancer who registered in the Institute for Gastroenterology and Liver Diseases, Shahid Beheshti University of Medical Sciences (Tehran, Iran) from 2004 to 2015 in a retrospective study. Analysis was performed using competing risks model and Weibull distribution. Software used for data analysis was R, and significance level was regarded as 0.05.

RESULTS

The result indicated that, at the end of follow-up, 111 (29.8%) deaths were from colorectal cancer and 14 (3.8%) deaths were due to other diseases. The average body mass index (BMI) was 24.61(SD 3.98). The mean survival time for a patient in 372 was 62.05(SD 48.78) month with median equals to 48 months. According to competing-risks method, only stageIII (HR, 1.69; 95% CI, 1.246-2.315 ), stageIV( HR, 4.51; 95% CI,2.91-6.99 ) and BMI( HR, 0.96; 95% CI, 0.96-0.975) have a significant effect on patient's survival time.

CONCLUSION

This study indicated pathologic stage (III,IV) and BMI as the prognosis, using a Weibull model with competing risks analysis, while other models without the competing events lead to significant predictors which may be due to over-estimation.

Person centered prediction of survival in population based screening program by an intelligent clinical decision support system

AIM

To survey person centered survival rate in population based screening program by an intelligent clinical decision support system.

BACKGROUND

Colorectal cancer is the most common malignancy and major cause of morbidity and mortality throughout the world. Colorectal cancer is the sixth leading cause of cancer death in Iran. In this survey, we used cosine similarity as data mining technique and intelligent system for estimating survival of at risk groups in the screening plan.

METHODS

In the first step, we determined minimum data set (MDS). MDS was approved by experts and reviewing literatures. In the second step, MDS were coded by python language and matched with cosine similarity formula. Finally, survival rate by percent was illustrated in the user interface of national intelligent system. The national intelligent system was designed in PyCharm environment.

RESULTS

Main data elements of intelligent system consist demographic information, age, referral type, risk group, recommendation and survival rate. Minimum data set related to survival comprise of clinical status, past medical history and socio-demographic information. Information of the covered population as a comprehensive database was connected to intelligent system and survival rate estimated for each patient. Mean range of survival of HNPCC patients and FAP patients were respectively 77.7% and 75.1%. Also, the mean range of the survival rate and other calculations have changed with the entry of new patients in the CRC registry by real-time.

CONCLUSION

National intelligent system monitors the entire of risk group and reports survival rates by electronic guidelines and data mining technique and also operates according to the clinical process. This web base software has a critical role in the estimation survival rate in order to health care planning.

The pathological behaviors and prognostic factors of Chinese and Japanese colorectal cancers from general hospitals: a comparative study of the inpatients with surgical operation

Here, we collected the information of 17304 and 2014 inpatients with colorectal cancer (CRC) from general hospitals of China and Japan respectively, and analyzed microscopic and macroscopic aspects, even stratified by the age and gender. It was found that Chinese CRC patients showed younger prone, more rectal and ascending cancers, less sigmoid and transverse cancers, larger size, less invasion into lymphatic system or metastasis into lymph node, and poorer differentiation than Japanese ones (p < 0.05). TNM staging was employed as an independent factor for the prognosis of the CRC patients regardless of the country (p < 0.05). Female patients showed larger tumor size, easier invasion and metastasis into lymphatic system, and worse differentiation than males (p < 0.05). The younger patients displayed frequent invasion and metastasis into lymphatic system, and poor differentiation in comparison to elder ones (p < 0.05). These findings demonstrated that Japanese patients seemed to have more invasion and metastasis due to standard and precise operation and pathological diagnosis accuracy. Actually, Chinese patients had more aggressive pathological characteristics and a poorer prognosis. Therefore, it is essential to establish a routine screening methodology, a standard treatment system and postoperative diagnosis protocol for the prevention and therapeutics of Chinese CRC patients, especially for female and young patients.

Epidemiology of colorectal cancer

Colorectal cancer is currently the third deadliest cancer in the United States and will claim an estimated 49,190 U.S. lives in 2016. The purpose of this review is to summarize our current understanding of this disease, based on nationally published statistics and information presented in peer-reviewed journal articles. Specifically, this review will cover the following topics: descriptive epidemiology (including time and disease trends both in the United States and abroad), risk factors (environmental, genetic, and gene-environment interactions), screening, prevention and control, and treatment. Landmark discoveries in colorectal cancer risk factor research will also be presented. Based on the information reviewed for this report, we suggest that future U.S. public health efforts aim to increase colorectal cancer screening among African American communities, and that future worldwide colorectal cancer epidemiology studies should focus on researching nutrient-gene interactions towards the goal of improving personalized treatment and prevention strategies.

Low Level of Microsatellite Instability Correlates with Poor Clinical Prognosis in Stage II Colorectal Cancer Patients

The influence of microsatellite instability (MSI) on the prognosis of colorectal cancer (CRC) requires more investigation. We assessed the role of MSI status in survival of individuals diagnosed with primary colorectal cancer. In this retrospective cross-sectional study the MSI status was determined in 158 formalin-fixed paraffin-embedded tumors and their matched normal tissues from patients who underwent curative surgery. Cox proportional hazard modeling was performed to assess the clinical prognostic significance. In this study we found that MSI-H tumors were predominantly located in the colon versus rectum (p = 0.03), associated with poorer differentiation (p = 0.003) and TNM stage II/III of tumors (p = 0.02). In CRC patients with stage II, MSI-L cases showed significantly poorer survival compared with patients who had MSI-H or MSS tumors (p = 0.04). This study indicates that MSI-L tumors correlate with poorer clinical outcome in patients with stage II tumors (p = 0.04) or in tumors located in the colon (p = 0.02). MSI-L characterizes a distinct subgroup of CRC patients who have a poorer outcome. This study suggests that MSI status in CRC, as a clinical prognostic marker, is dependent on other factors, such as tumor stage and location.

Comparison of recovery effect for sufentanil and remifentanil anesthesia with TCI in laparoscopic radical resection during colorectal cancer

The aim of the present study was to compare the recovery of sufentanil and remifentanil anesthesia by target-controlled infusion (TCI) in elderly patients with laparoscopic-assisted radical resection of colorectal cancer. The effect of anesthesia on patient stress response and cellular immune function was also observed. Elderly patients (n=192) who underwent laparoscopic radical resection of colorectal cancer between July 2014 and October 2015 were randomly divided into the sufentanil and remifentanil groups (n=96 per group). The two groups used sufentanil- and remifentanil-based anesthesia by TCI. The wake-up time, extubation time, orientation recovery time, vital signs, stress response, distribution of T-cell subsets and incidence of adverse reactions were recorded and compared. The wake-up and extubation times of the remifentanil group were significantly shorter than those of the sufentanil group. The difference of orientation recovery time was not statistically significant. The differences in heart rate, mean arterial pressure, and arterial oxygen saturation following anesthesia and during surgery and those prior to anesthesia of the sufentanil group were not statistically significant. However, those of the remifentanil group significantly improved following anesthesia. The concentrations of glucose, cortisol (COR), and interleukin-6 and C-reactive protein were stable in the sufentanil group, whereas the indices in the remifentanil group had a tendency of increasing during the anesthesia and surgery, and had a longer postoperative recovery time. The decreasing degree of T-cell subsets in the sufentanil group was significantly lower than that in the remifentanil group, and had a short recovery of cellular immunity following surgery. The adverse reactions rate during anesthesia of the remifentanil group was significantly higher than that of the sufentanil group. In conclusion, sufentanil- and remifentanil-based anesthesia with TCI has certain advantages, including improved recovery effect, less stress response, less inhibition of cellular immunity and fewer adverse reactions. It has the potential to become the first choice of anesthetic in the clinic for elderly patients who undergo laparoscopic radical resection for colorectal cancer.

Validation of a Multiplex Allele-Specific Polymerase Chain Reaction Assay for Detection of KRAS Gene Mutations in Formalin-Fixed, Paraffin-Embedded Tissues from Colorectal Cancer Patients

Background

Patients with KRAS mutations do not respond to epidermal growth factor receptor (EGFR) inhibitors and fail to benefit from adjuvant chemotherapy. Mutation analysis of KRAS is needed before starting treatment with monoclonal anti-EGFR antibodies in patients with metastatic colorectal cancer (mCRC). The objective of this study is to develop a multiplex allele-specific PCR (MAS-PCR) assay to detect KRAS mutations.

Methods

We developed a single-tube MAS-PCR assay for the detection of seven KRAS mutations (G12D, G12A, G12R, G12C, G12S, G12V, and G13D). We performed MAS-PCR assay analysis for KRAS on DNA isolated from 270 formalin-fixed paraffin-embedded (FFPE) colorectal cancer tissues. Sequences of all 270 samples were determined by pyrosequencing. Seven known point-mutation DNA samples diluted with wild-type DNA were assayed to determine the limitation of detection and reproducibility of the MAS-PCR assay.

Results

Overall, the results of MAS-PCR assay were in good concordance with pyrosequencing, and only seven discordant samples were found. The MAS-PCR assay reproducibly detected 1 to 2% mutant alleles. The most common mutations were G13D in codon 13 (49.17%), G12D (25.83%) and G12V (12.50%) in codon 12.

Conclusion

The MAS-PCR assay provides a rapid, cost-effective, and reliable diagnostic tool for accurate detection of KRAS mutations in routine FFPE colorectal cancer tissues.

Determination of Effective Factors on Survival of GI Cancers: Results of Five Years Follow up in Iranian Population

Background:

The gastrointestinal cancers are among the most common cause of cancer-related death and their long term survival is very low. This study was aimed to determine the effective factors on survival of gastrointestinal cancers among Iranian population during 5 years of follow up.

Methods:

In total, 157 patients diagnosed as gastrointestinal cancers from 2007 to 2009 in the only center of endoscopy in Alvand city, northwest of Qazvin province were included and followed for five years. The univariate and multivariate analysis were done using Kaplan-Meier method and the Cox model respectively.

Results:

Observations of 146 patients were analyzed (99 (67.8%) males and 47 (32.2%) females). The mean age was 64.73± 13.23 and 58.28±13.91 for females and males respectively. The one and three years survival rates for esophageal cancer were 28% and 9% and the one, three and five years survival rates for gastric cancer were 31%, 26% and 14% and for colorectal cancer were 96%, 86% and 75% respectively. In the univariate analysis, variables of age, educational level, ethnicity, smoking, type of cancer, stage of disease and type of treatment had significant effects on survival. In the multivariate analysis, the type of cancer and type of treatment affected the survival of patients as effective factors (p<005).

Conclusion:

Patients with esophageal cancer and those who underwent RT &/or CT are exposed to higher risk of death. Combination therapies (Surgery and adjuvant or neoadjuvant therapy) were related to be her survival. Early diagnosis and use of extended cancer screening programs seem necessary to improve survival.

Increased colorectal cancer incidence in Iran: a systematic review and meta-analysis

BACKGROUND

Colorectal cancer is the third most common cancer in Iran. The increasing trend of colorectal cancer incidence in Iran and the close relationship with the geographical location are the underlying reasons for this study.

METHODS

DATA SOURCE

Eleven databases, including MEDLINE, EMBASE, SCOPUS, and four other databases, for articles in Persian were searched from April 2014 to October 2014. Additional data were obtained from an online survey of the Central Library of Tabriz Faculty of Medicine.

STUDY ELIGIBILITY CRITERIA

In this systematic review and meta-analysis, we included studies reporting different measures of incidence, age-standardized incidence rates, and crude incidence rates. All rates (per 100,000 person-years) were standardized to the world standard population.

STUDY APPRAISAL AND SYNTHESIS METHODS

A preliminary review of the title and abstracts of these articles was used to exclude any that were clearly irrelevant. The full text review determined whether the article was relevant to our topic. All the potentially relevant manuscripts were reviewed by two other investigators (S.D., M.G.). A total of 39 studies (10 Persian and 29 English articles) from different provinces and diverse areas of Iran, were analyzed in this study using comprehensive meta-analysis software. For accuracy studies, we used estimated rates for males and females with 95 % confidence intervals.

RESULTS

Age-standardized incidence rates were obtained based on the random effects model and were 8.16 (95 % CI: 6.64 to 9.68) and 6.17 (95 % CI: 5.01 to 7.32) for males and females, respectively. The random crude rates were 5.58 (95 % CI: 4.22 to 6.94) for males and 4.01 (95 % CI: 3.06 to 4.97) for females.

CONCLUSIONS

Colorectal cancer incidence rates rise due to individual and environmental risk factors as well as improvement in the registry system and increase in access to health services. A more executed organized and structured system for collecting cancer data, in all cities and rural areas of the country, is an essential priority.