Colorectal carcinoma: a retrospective, descriptive study of age, gender, subsite, stage, and differentiation in Iran from 1995 to 2001 as observed in Tehran University

Epidemiological trends of colorectal cancer cases in young population of Eastern India: A retrospective observational study

BACKGROUND

Colorectal cancer (CRC) is a disease of the older population in developed countries where the incidence among the young is rising despite the decline in the overall incidence. Contrary to this, in India, which is a low-incidence country for CRCs, the incidence among all age groups including the young is rising. This study aimed at describing the clinico-demographic profile of young CRC cases and the epidemiological trend of the proportion of young cases from 2014 to 2021 in a tertiary cancer center in Eastern India.

METHODS

This retrospective observational study was conducted at Department of Radiation Oncology, State Cancer Institute, IGIMS Patna, India a prominent tertiary cancer care center of Bihar. All histopathologically confirmed CRC cases in the 0-39 years age group were considered young and evaluated for the clinical, demographic profile as well as yearly trends in proportion out of total CRC cases. Microsoft Excel (2021) was used for statistical analysis. A P value of 0.05 was considered significant.

RESULTS

Young colorectal (less than 40 years) patients constituted a third (n = 344, 33.4%) of total colorectal (n = 1028) cases. The median age among the young CRC cases was 30 years (range: 12 to 39 years). Rectum was the most common subsite noted (n = 255,74.1%) among this group of young patients. The most commonly encountered stage of the disease was III (n = 107, 31.1%) and chemotherapy was the most common treatment offered (n = 153, 44.5%). The proportion of young (0-39 years) CRC cases ranged between 29.4 and 37.4 (mean 33.5 ± 2.77, P value = 0.725) over the calendar years of the study period.

CONCLUSION

The proportion of young (<40 years of age) cases out of total CRC cases in our study is higher than that in developed countries. However, the trends of this proportion have been consistent over the study period, i.e., from 2014 to 2021 without any significant change in our hospital-based cancer registry. Rectal cancer affected nearly three out of every four CRC patients in this age group. More advanced disease at presentation emphasizes the need for measures of screening, early diagnosis, and adequate infrastructure for treatment.

Clinico-epidemiological profile and treatment outcome in adolescents and young patients of rectal cancer attending a tertiary cancer center

INTRODUCTION

The incidence of colorectal cancer in young adults is on an increasing trend. It is observed that this subgroup of patients has an aggressive disease and carries a poorer prognosis compared to its older counterpart. This study aimed to analyze the incidence, treatment outcome, and prognostic factors in adolescents and young adults with rectal cancer attending a tertiary cancer center in North India.

MATERIALS AND METHODS

We retrospectively analyzed 50 patients of histologically proven rectal cancer, aged up to 30 years, treated at our center between 2015 and 2019. The clinical, demographic, and pathological parameters were studied in all these patients. Kaplan-Meier survival analysis was used to find out survival. Univariate analysis was performed to assess prognostic factors.

RESULTS

The incidence was 26.4% at our center with a median age of 28 years. Bleeding per rectum was the commonest complaint. Most of them had signet ring cell histology (26%). The median overall survival was 16 months. Survival was significantly better in patients having bleeding per rectum as an initial complaint (P = 0.009), absence of lymphovascular invasion (LVI) (P = 0.005), and perineural invasion (PNI) (P = 0.002), who received complete planned treatment compared to patients who could not receive either of the modality (P < 0.001). Patients who did not receive radiotherapy (RT) had the worst outcomes compared to those who received RT in any form. RT dose of 50.4 Gy was found to be superior as compared to other schedules. There was no significant difference in survival with gender, tumor stage, grade, type of surgery, or chemotherapy regimen.

CONCLUSION

The majority of patients presented in an advanced stage. Therefore, bleeding per rectum should be properly and timely investigated in all these young patients. Early detection and complete treatment are paramount to improving the outcome.

Colorectal adenocarcinoma in Uganda: are right-sided and left-sided colon cancers two distinct disease entities?

INTRODUCTION

In Western countries, right-sided colon cancers (RSCC) present at an older age and advanced stage. Researchers believe that there is a difference between left-sided colon cancer (LSCC) and RSCC. In Uganda, however, it is unknown whether differences exist in the pathological profile between RSCC and LSCC. The aim of this study was to determine the differences in clinicopathological characteristics between RSCC and LSCC in Ugandan patients.

METHODOLOGY

A cross-sectional study was conducted in which colorectal adenocarcinoma formalin-fixed paraffin-embedded tissue (FFPE) blocks were obtained from 2008 to 2021. Colorectal specimens were obtained from prospectively recruited patients. In the retrospective study arm, FFPE blocks and data were obtained from the archives of pathology laboratory repositories. Parameters studied included age, sex, location of the tumour, grade, stage, lymphovascular (LVI) status, and histopathological subtype between LSCC and RSCC.

RESULTS

Patients with RSCC were not older than those with LSCC (mean age, 56.3 years vs 53.5 years; p = 0.170). There was no difference in the stage between RSCC and LSCC. Poorly differentiated tumours were more commonly found in RSCC than in LSCC (18.7% vs 10.1%; p = 0.038). Moderately and poorly differentiated colonic tumours were more common with RSCC (89.3%) than with LSCC (75.1%) (p = 0.007). Younger patients had more poorly differentiated tumours than older patients (19.6% versus 8.6%; p = 0.002). LVI was more common with RSCC than with LSCC (96.8% vs 85.3%; p = 0.014). Mucinous adenocarcinoma (MAC) was more common with RSCC (15.8%) compared with LSCC (8.5%) (p = 0.056) although statistical significance was borderline.

CONCLUSIONS

Clinicopathological features of RSCCs tend to be different from those of LSCCs. RSCCs tend to be associated with MAC, a higher grade and LVI status compared to LSCC. LSCC and RSCC present predominantly with an advanced stage; therefore, national screening programmes for the early detection of CRC are necessary to reduce mortality in our Ugandan population.

Association of chromosome 2 open reading frame 71 in colorectal cancer susceptibility

BACKGROUND

Colorectal cancer (CRC) is a serious threat to human physical and mental health. Due to the novelty of the open reading frame (ORF), ORF has shown a wide range of new genetic associations in cancer. The purpose of this study was to explore the association between the C2orf71 SNPs and CRC susceptibility.

METHODS

We recruited 1419 participants to perform an association analysis between C2orf71 SNPs and CRC risk through SNPStats online solftware. Genotyping was completed by the AgenaMassARRAY. In addition, we used false-positive report probability analysis to detect whether the positive findings were noteworthy observations. We also used Haploview 4.2 software and SNPStats online software to conduct the haplotype analysis and analysis of linkage disequilibrium (LD). Finally, the interaction of SNP-SNP in CRC risk was evaluated by multi-factor dimensionality reduction (MDR).

RESULTS

The overall analysis showed thatC2orf71-rs17744093, -rs10200693, and -rs13385188 were significantly associated with the CRC susceptibility. C2orf71-rs17744093 was associated with CRC risk under dominant model (OR = 1.25, p = 0.048). -rs10200693 was associated with CRC risk under allele (OR = 1.17, p = 0.041) and log-additive model (OR = 1.16, p = 0.045). -rs13385188 had significant association with CRC risk under multiple genetic models (allele: OR = 1.19, p = 0.023; log-additive: OR = 1.18, p = 0.026). Multiple stratified analyses showed that except for the three candidate SNPS mentioned above, -rs10166913 (age < 60 years and drinking) and -RS17007544 (< 60 years) were associated with increased CRC risk.

CONCLUSION

C2orf71-rs17744093, -rs10200693, -rs10166913, -rs17007544, and -rs13385188 were associated with CRC susceptibility.

Colorectal Cancer in North-Eastern Iran: a retrospective, comparative study of early-onset and late-onset cases based on data from the Iranian hereditary colorectal cancer registry

BACKGROUND

The incidence rate of colorectal cancer (CRC) is increasing among patients below 50 years of age. The reason for this is unclear, but could have to do with the fact that indicative variables, such as tumour location, gender preference and genetic preponderance have not been followed up in a consistent mann er. The current study was primarily conducted to improve the hereditary CRC screening programme by assessing the demographic and clinicopathological characteristics of early-onset CRC compared to late-onset CRC in northeast Iran.

METHODS

This retrospective study, carried out over a three-year follow-up period (2014-2017), included 562 consecutive CRCs diagnosed in three Mashhad city hospital laboratories in north-eastern Iran. We applied comparative analysis of pathological and hereditary features together with information on the presence of mismatch repair (MMR) gene deficiency with respect to recovery versus mortality. Patients with mutations resulting in absence of the MMR gene MLH1 protein product and normal BRAF status were considered to be at high risk of Lynch syndrome (LS). Analyses using R studio software were performed on early-onset CRC (n = 222) and late-onset CRC (n = 340), corresponding to patients ≤50 years of age and patients > 50 years.

RESULTS

From an age-of-onset point of view, the distribution between the genders differed with females showing a higher proportion of early-onset CRC than men (56% vs. 44%), while the late-onset CRC disparity was less pronounced (48% vs. 52%). The mean age of all participants was 55.6 ± 14.8 years, with 40.3 ± 7.3 years for early-onset CRC and 65.1 ± 9.3 years for late-onset CRC. With respect to anatomical tumour location (distal, rectal and proximal), the frequencies were 61, 28 and 11%, respectively, but the variation did not reach statistical significance. However, there was a dramatic difference with regard to the history of CRC in second-degree relatives between two age categories, with much higher numbers of family-related CRCs in the early-onset group. Expression of the MLH1 and PMS2 genes were significantly different between recovered and deceased, while this finding was not observed with regard to the MSH6 and the MSH2 genes. Mortality was significantly higher in those at high risk of LS.

CONCLUSION

The variation of demographic, pathological and genetic characteristics between early-onset and late-onset CRC emphasizes the need for a well-defined algorithm to identify high-risk patients.

A clinical study of newly-diagnosed colorectal cancer over 2 years in a gastroenterology center in Iraq

Background and study aims Colorectal cancer (CRC) is the most common gastrointestinal cancer and the third most commonly diagnosed malignancy affecting about one million individuals each year. The etiology for most cases of CRC appears to be related to environmental factors. This study to describe the main characteristics of this malignancy regarding age, gender, and anatomical sub site distribution, as well as the main presenting symptoms in Iraqi patients.

Patients and methods Patients with newly-diagnosed CRC by colonoscopy findings and confirmed by histopathological examination of endoscopic colonic biopsies were studied.

Results Sixty three cases with a newly-diagnosed CRC were included in this study. There were 31 (49.2%) males and 32 (50.8%) females. CRC peaked in the 60–69 years old age group (p < 0.05), more than 60% were between 40 and 69 years old. Fresh bleeding per rectum was the most common symptom occurred in 48 (76.2%) patients; while the least common was weight loss (19%). The mean duration of symptoms before referral was 7.3 ± 12.6 months. The tumor sites of the CRC were the rectum and sigmoid region seen in 77.8% (p < 0.05), the rectum alone reported in 37 patients (58.7%); followed by sigmoid colon in 12 (19%) patients, cecum in 7 (11.1%) patients and the ascending colon seen in 2 (3.2%) patients.

Conclusions In this study CRC occurs in relatively younger age groups in comparison to studies in the developed countries with rectal cancer predominates of all colorectal cancers.

Clinical characteristics and survival profile of young versus old colorectal cancer patients at a tertiary cancer center in North India over a period of 5 years

Background

Colorectal cancer (CRC) is mostly considered a disease of the elderly. But the rate is increasing among young adults and is associated with different clinical patterns. The objective was to study the frequency of CRC in young patients and compare the clinicopathological profile and survival with the older cohort.

Methods

Five-year (2012-2016) data of the 912 consecutive CRC cases treated at the center were analyzed. Clinical and histopathological characteristics were compared in young (≤40) and older (>40) patients. Descriptive statistics were used for data presentation. Categorical data were compared by the Chi-square test; survival analyses were performed by Kaplan-Meier method.

Results

In total, 231 (25.3%) and 681 (74.7%) cases were in the young and older age groups, respectively. Male predominance was noted. Young patients presented predominantly in stage III (46%). Majority of the young patients harbored left-sided tumors (75.8% vs 63.7% in old patients, P = 0.001) and rectum was the favored site in young patients (53.7% vs 37%; P < 0.001). Poorly differentiated adenocarcinoma was more common in the young age group (46.88% vs 24.16% in old patients, P < 0.001), also signet-ring cell morphology occurred more often in young patients (11.7% vs 4%, P < 0.001). Survival was inferior in the patients presenting at an advanced stage or with adverse histology or poor tumor grade. However, stage-specific survival showed no significant difference between both groups.

Conclusion

This study shows that though young CRC patients present with higher stage, aggressive morphology, and predominantly rectal localization, the overall survival and stage-specific survival did not differ significantly from the older patients.

Familial and non-familial risk factors associated with colorectal cancer survival in young and middle-aged patients

BACKGROUND

Survival following colorectal cancer (CRC) survival may be influenced by a number of factors including family history, individual medical history, and comorbidities. The impact of these factors may vary based on the patient's age.

METHODS

The study cohort consisted of individuals born in Western Australia between 1945 and 1996, who had been diagnosed with CRC prior to 2015 (n = 3220). Hospital, cancer, and mortality data were extracted for each patient from state health records and were used to identify potential risk factors associated with CRC survival. Family linkage data, in combination with cancer registry data, were used to identify first-degree family members with a history of CRC. The association between survival following CRC diagnosis and identified risk factors was examined using Cox proportional hazard models.

RESULTS

Age and sex were not significantly associated with survival in young patients. However, in middle-aged patients increasing age (HR 1.03, 95% CI 1.01-1.05, p = 0.003) and being male (HR 0.72, 95% CI 0.60-0.87, p < 0.001) were associated with reduced survival. Being diagnosed with polyps and having a colonoscopy prior to CRC diagnosis were associated with improved survival in both young and middle-aged patients, while a history of non-CRC and liver disease was associated with reduced survival. In middle-aged patients, having diabetes-related hospital admissions (HR 1.53, 95% CI 1.15-2.03, p = 0.004) was associated with reduced survival.

CONCLUSIONS

In both young and middle-aged patients with CRC, factors associated with early screening and detection were associated with increased CRC survival while a history of liver disease and non-CRC was associated with decreased CRC survival.

Global Increasing Incidence of Young-Onset Colorectal Cancer Across 5 Continents: A Joinpoint Regression Analysis of 1,922,167 Cases

BACKGROUND

Colorectal cancer incidence among young adults in the United States is on the rise, but whether this phenomenon is present in other parts of the world is not well documented. This study aims to explore the temporal change of incidence rates for colorectal cancer in various countries across the globe.

METHODS

We extracted colorectal cancer incidence and population data from 1988 to 2007 based on data from the International Agency for Research on Cancer and compared incidence between age groups. Twelve representative jurisdictions from five continents were selected. Young-onset colorectal cancer cases were defined as those ages <50 years. Joinpoint regression was used to measure the trends of colorectal cancer incidence and to estimate the annual percent change (APC).

RESULTS

The APC for those ages <50 years was noted to be increasing at a faster rate as compared with those ages ≥50 years in many regions, including Australia (+1.10% vs. -0.35%), Brazil (+9.20% vs. +5.72%), Canada (+2.60% vs. -0.91%), China-Hong Kong (+1.82% vs. -0.10%), China-Shanghai (+1.13% vs. -2.68%), Japan (+2.63% vs. +0.90%), the United Kingdom (+3.33% vs. +0.77%), and the United States (+1.98% vs. -2.88%). These trends were largely driven by rectal cancer, except in Brazil and the United Kingdom.

CONCLUSIONS

Increasing incidence of young-onset colorectal cancer was noted in many regions across the globe.

IMPACT

Further studies focusing on young-onset colorectal cancer, particularly with regard to risk factors and establishing the optimal age of screening, are warranted.

Clinical and Molecular Comparative Study of Colorectal Cancer Based on Age-of-onset and Tumor Location: Two Main Criteria for Subclassifying Colorectal Cancer

Our aim was to characterize and validate that the location and age of onset of the tumor are both important criteria to classify colorectal cancer (CRC). We analyzed clinical and molecular characteristics of early-onset CRC (EOCRC) and late-onset CRC (LOCRC), and we compared each tumor location between both ages-of-onset. In right-sided colon tumors, early-onset cases showed extensive Lynch syndrome (LS) features, with a relatively low frequency of chromosomal instability (CIN), but a high CpG island methylation phenotype. Nevertheless, late-onset cases showed predominantly sporadic features and microsatellite instability cases due to BRAF mutations. In left colon cancers, the most reliable clinical features were the tendency to develop polyps as well as multiple primary CRC associated with the late-onset subset. Apart from the higher degree of CIN in left-sided early-onset cancers, differential copy number alterations were also observed. Differences among rectal cancers showed that early-onset rectal cancers were diagnosed at later stages, had less association with polyps, and more than half of them were associated with a familial LS component. Stratifying CRC according to both location and age-of-onset criteria is meaningful, not only because it correlates the resulting categories with certain molecular bases, but with the confirmation across larger studies, new therapeutical algorithms could be defined according to this subclassification.

Incidence of colorectal cancer in young patients

Sporadic colorectal cancer (CRC) is traditionally diagnosed after de sixth decade of life, although a small percentage of cases are diagnosed in patients under 40 years of age, and incidence is increasing. There exists a great volume of controversy regarding clinical outcome of young patients diagnosed with colorectal cancer (CRC) when compared to elder counterparts. Our aims were to evaluate the rate of CRC in young patients, to review the pertaining literature and to discuss outcomes and clinical prognosis. A retrospective review involving patients with CRC was undertaken, focusing on age at diagnosis. The information extracted from this literature review showed a trend towards a decreased incidence in older people with an opposite effect among adolescents and young adults. Moreover, biological aggressiveness in young adults diagnosed with CRC has not been fully recognized, although it is usually diagnosed later and in association with adverse histological features. Besides that, these features don't affect outcome. These apparent increase in CRC incidence among young patients during the last decades raises the need for a greater suspicious when evaluating common symptoms in this group. Thus, educational programs should widespread information for both population and physicians to improve prevention and early diagnosis results.

Estimation and Projection of Prevalence of Colorectal Cancer in Iran, 2015-2020

Background:

Population aging and more prevalent westernized lifestyle would be expected to result in a markedly rising burden of colorectal cancer (CRC) in the future years. The aim of this study is to estimate the limited-time prevalence of CRC in Iran between 2015 and 2020.

Materials and Methods:

Aggregated CRC incidence data were extracted from the Iranian national cancer registry (IR.NCR) reports for 2003–2009 and from GLOBOCAN-2012 database for 2012. Incidence trends were analyzed by age groups, genders, histopathologic, and topographic subtypes to estimate annual percentage changes. Incidence was projected for 2020. The prevalence was estimated applying an adopted version of a previously introduced equation to estimate limited–time prevalence based on the incidence and survival data. Monte Carlo sensitivity analyses were applied to estimate 95% uncertainty levels (ULs). In each scenario, incidence, survival, annual percentage changes, and completeness of case ascertainment at IR.NCR were replaced under pre-assumed distributions.

Results:

Number of estimated within 1, 2-3 and 4-5-year CRC patients in 2015 were 13676 (95% UL: 10051–18807), 20964 (15835–28268), and 14485 (11188–19293), respectively. Estimated 5-year prevalence for 2020 (99463; 75150–134744) was 2.03 times of that for 2015. Highest 5-year prevalence was estimated in ages 55–59 for females and 75 + for males. Adenocarcinoma (41376; 31227 55898) was the most prevalent histologic subtype. The most prevalent tumor location was colon (30822, 23262–41638).

Conclusion:

A substantial growth in the prevalence of CRC survivors is highly expected for future years in Iran. Establishment of specialized institutes is highly recommended to provide medical and especially social supports for Iranian CRC survivors.

Colorectal cancer in young adults: A difficult challenge

Sporadic colorectal cancer (CRC) is traditionally diagnosed after the sixth decade of life, and current recommendations for surveillance include only patients older than 50 years of age. However, an increasing incidence of CRC in patients less than 40 years of age has been reported. This occurrence has been attributed to different molecular features and low suspicion of CRC in young symptomatic individuals. When confronting young-onset CRC with older patients, issues such as biological aggressiveness, stage at diagnosis and clinical outcomes seem to differ in many aspects. In the future, the identification of the molecular profile underlying the early development of sporadic CRC will help to plan tailored screening recommendations and improve management. Besides that, differential diagnosis with CRC linked with hereditary syndromes is necessary to provide adequate patient treatment and family screening. Until we find the answers to some of these doubts, doctors should raise suspicion when evaluating an young adult and be aware of this risk and consequences of a late diagnosis.

Association between proto-oncogene mutations and clinicopathologic characteristics and overall survival in colorectal cancer in East Azerbaijan, Iran

Background

Colorectal cancer (CRC) is the third-most common cancer in Iran. The increasing incidence of CRC in the past three decades has made it a major public health burden in the country. This study aimed to determine any relationship of specific mutations in CRCs with clinicopathologic aspects and outcome of patients.

Materials and methods

This study was conducted on 100 CRC patients by the case-only method. Polymerase chain-reaction products were analyzed by Sanger sequencing, and sequence results were compared with the significant KRAS and BRAF gene mutations in the My Cancer Genome database. Logistic regression models were used to detect associations of clinicopathologic characteristics with each of the mutations. Kaplan–Meier and Cox regression models were constructed to estimate overall survival in patients.

Results

A total of 26 subjects (26%) had heterozygote-mutant KRAS, and mutations were not detected in the amplified exon of BRAF in both tumor and normal tissues of the 100 CRCs. Rectal tumors had 1.53-fold higher likelihood of KRAS mutations than colon tumors, and men had 1.37-fold higher odds than women. The presence of metastasis increased the likelihood of KRAS mutations 2.36-fold over those with nonmetastatic CRCs. Compared to patients with KRAS wild-type cancers, those with KRAS mutations had significantly higher mortality (hazard ratio 3.74, 95% confidence interval 1.44–9.68; log-rank P=0.003).

Conclusion

Better understanding of the causality of CRC can be established by combining epidemiology and research on molecular mechanisms of the disease.

Study of Clinicopathological Profile of Sporadic Cases of Colorectal Cancer

Objectives

Colorectal cancer (CRC) is the third leading cause of cancer-related deaths in the world. This study was carried out to see the epidemiological and clinicopathological profile of sporadic cases of CRC in Bangladesh.

Materials and methods

The patients diagnosed to have colorectal carcinoma in two private medical centers of Bangladesh from January 2012 to December 2014 were enrolled in this study. Demographic data, clinical presentations, site of lesions, and histological types were analyzed.

Results

Total 158 patients were included in this study. The mean age was 50.77 years and male to female ratio was 1.55:1. Rectal bleeding was the commonest symptom irrespective of age and sex followed by abdominal pain (33, 20.9%), weight loss (29, 18.3%), abdominal mass (26, 16.4%), and altered bowel habit (22, 13.9%). Common histological type was adenocarcinoma (156, 98.7%).

Conclusion

Colorectal cancer commonly affects males >40 years of age. Most common site of involvement is rectum, which is followed by left colon.

How to cite this article

Saha M, Shil BC, Saha SK, Banik RK, Perveen I, Chowdhury MKS, Nazmul Islam ASM, Saifullah ANM. Study of Clinicopathological Profile of Sporadic Cases of Colorectal Cancer. Euroasian J Hepato-Gastroenterol 2016;6(2):134-136.

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.

Evaluation of the left-to-right shift of colon tumors in Iran: Is the trend changing?

Background:

Colorectal cancer (CRC) is the second cause of cancer-related deaths worldwide. There have been several studies reporting the proximal tumor shift, especially in Western countries. In the present study, we investigated the clinicopathologic and anatomical distributions of colorectal tumors in Iranian CRC patients.

Materials and Methods:

In this retrospective cohort study, 258 patients with CRC from 2008 to 2013 were evaluated. Comparison of variables was performed using Pearson's chi-square test and Fisher's exact test depending on the nature of the data.

Results:

A total of 258 patients including 124 (48.1%) females and 134 (51.9%) males enrolled in this study. The majority of cancers were detected in the rectosigmoid, i.e., 98 (38%) followed by the left colon, i.e., 84 (32.6%) and the right colon, i.e., 76 (29.5%). In the present study, we observed the significant association between metastases, adjuvant therapy, family history, and history of inflammatory bowel disease (IBD) with tumor, node, and metastasis (TNM) staging (P < 0.001). In univariate analysis, there was a strong association between overall survival (OS) and stage II CRC (P = 0.03). However, the predictive value was lost in multivariate analysis (P = 0.145).

Conclusion:

Unlike the majority of previous studies on Iranian CRC patients, we observed a considerably higher occurrence of right-sided colon cancers (84 versus 76). Although this phenomenon did not reach the statistical significance rate, based on recent studies on Iranian population including the present one, the pattern of anatomical distribution of colorectal tumors has been changed toward the proximal colon. This requires an urgent need to provide other strategies and complementary detecting approaches in order to identify proximal tumors in Iranian CRC patients.

Comparative Study of Carcinoembryonic Antigen Tumor Marker in Stomach and Colon Cancer Patients in Khyber Pakhtunkhwa

BACKGROUND

Due to the increase in morbidity and mortality rate, cancer has become an alarming threat to the human population worldwide. Since cancer is a progressive disorder, timely diagnosis would be helpful to prevent/stop cancer from progressing to severe stage. In Khyber Pakhtunkhwa, Pakistan, most of the time, tumors are diagnosed with endoscopy and biopsy; therefore rare studies exist regarding the diagnosis of gastrointestinal (GIT) carcinomas based on tumor markers, especially CEA.

OBJECTIVES

This study made a comparative analysis of CEA in admitted hospitalized stomach and colon cancer patients diagnosed as GIT with biopsy.

MATERIALS AND METHODS

In this study, a total of 66 cases were included. The level of CEA was determined in the blood of these patients using ELISA technique.

RESULTS

Out of 66 patients, the level of CEA was high in 59.1% of the total, 60.7% in colon cancer patients and 57.9 % in stomach cancer patients. Moreover, the incidence of colorectal and stomach cancer was greater in males as compared to females. Patients were more of the age group of 40- 60 and the level of CEA was comparatively higher in patients (51.5%) with histology which was moderately differentiated, than patients with well differentiated and poorly differentiated tumor histology.

CONCLUSIONS

CEA level was high in more than 50% of the total patients. Moreover, CEA exhibited higher sensitivity for colon than stomach cancer.

Age and site of Colonic Neoplastic Lesions: Implications of screening in South Asia

Objective : To evaluate the Age of patients and the site of Colonic Neoplastic Lesions (CNL) and to determine the appropriate screening strategy for Colorectal Carcinoma (CRC) (sigmoidoscopy versus colonoscopy) in our population. Methods : This is a cross sectional study. Data of all patients more than 16 years of age who underwent full colonoscopic examination at the Aga Khan University hospital between January 2011 till December 2013 and were diagnosed to have CRC or advanced adenomas (defined as polyp more than 1 cm and/or having villous morphology on histology) was recorded. Lesions found distal to the splenic flexure were characterized as distal lesions and while lesions found between the splenic flexure and the cecum were characterized as proximal lesions.

RESULTS

During the study period colonic neoplastic lesions were found in 217 patients; 186 (85.7%) patients had CRC and 31(14.3%) patients had advanced adenomatous polyps. Mean age was 55.8±14 years and amongst them 72 (33.2%) patients were less than 50 years of age while 145 (66.8%) were more than 50 years. In 144 (66.4%) patients lesions were located in the distal colon, 65 (30%) had lesions in the proximal colon while in 8 (3.7%) patients the neoplastic lesions were found both in the proximal and distal colon. The predominant symptoms were bleeding per rectum in 39.6% of patients followed by weight loss in 31.8% of patients. Only 3 patients had familial syndromes with multiple polyps. When patients younger than 50 years of age were compared with patients more than 50 years there was no statistically significant difference between the site of neoplastic lesion as well as the presenting symptoms. (p value 0.85).

CONCLUSION

Colonic Neoplastic Lesions presented at younger age in our study population and one third of the lesions were found in the right sided colon. Hence screening for CNLs should be implied at an earlier age preferably with colonoscopy. More population based data is required to further validate our results.

Colorectal cancer in iran: molecular epidemiology and screening strategies

Purpose. The increasing incidence of colorectal cancer (CRC) in the past three decades in Iran has made it a major public health burden. This study aimed to report its epidemiologic features, molecular genetic aspects, survival, heredity, and screening pattern in Iran. Methods. A comprehensive literature review was conducted to identify the relevant published articles. We used medical subject headings, including colorectal cancer, molecular genetics, KRAS and BRAF mutations, screening, survival, epidemiologic study, and Iran. Results. Age standardized incidence rate of Iranian CRCs was 11.6 and 10.5 for men and women, respectively. Overall five-year survival rate was 41%, and the proportion of CRC among the younger age group was higher than that of western countries. Depending on ethnicity, geographical region, dietary, and genetic predisposition, mutation genes were considerably diverse and distinct among CRCs across Iran. The high occurrence of CRC in records of relatives of CRC patients showed that family history of CRC was more common among young CRCs. Conclusion. Appropriate screening strategies for CRC which is amenable to early detection through screening, especially in relatives of CRCs, should be considered as the first step in CRC screening programs.

Ileocaecal junction carcinoma: a clinicopathological study of 199 cases

AIM

The ileocaecal junction (ICJ) region is an epithelial transition zone in which carcinomas are frequently diagnosed. However, it is currently unknown whether ICJ carcinomas (ICJ-CAs) have distinctive features. This study aimed to characterize the clinicopathological features of ICJ-CAs.

METHOD

All ileal and colorectal resections for carcinoma, performed in Calgary, Canada between January 2009 and June 2012, were reviewed. Carcinomas in which the epicentre was within 5 cm of the ileocaecal valve (ICV) were defined as ICJ-CAs. Of 1003 carcinomas studied, 199 (19.8%) were ICJ-CAs, including 93 (9.3%) that crossed the ICV. Comparison of clinicopathological features with carcinomas of the other ileo-colorectal regions was made. Survival was also assessed.

RESULTS

Clinically, ICJ-CAs were more common in female than male patients (56.3% female) compared with left-colonic (42.9% female) and rectal (37.9% female) carcinomas, and were more common in older age-groups of patients (71.8 ± 12.7 years) compared with appendiceal (62.6 ± 11.3 years), left-colonic (69.4 ± 12.3 years) and rectal (67.1 ± 11.9 years) carcinomas. Macroscopically, ICJ-CAs were similar to other colorectal carcinomas and were mostly described as ulcerated (63.3%). Histologically, ICJ-CAs had more mucinous, signet-ring cell and/or neuroendocrine features (39.7%, 8.0% and 7.5%, respectively) than did carcinomas of the left colon (16.8%, 1.6% and 1.1%, respectively) and the rectum (14.1%, 1.0% and 0.0%, respectively). They were higher grade (20.1% were high grade) than those of the left-colon (10.3%) and the rectum (9.8%). ICJ-CAs presented at a higher T-stage (25.6% were T4) compared with rectal carcinomas (11.6%). Most significantly, ICJ-CAs presented at a higher N-stage (25.6% were N2) than did right-colonic (14.1%) and rectal (16.2%) carcinomas. Although survival of patients with ICJ-CAs did not differ from those with right-colonic carcinomas, those with carcinomas directly involving the ICV did show a significantly decreased survival.

CONCLUSION

ICJ-CAs display several distinct clinicopathological features that may require special diagnostic, prognostic and management attention.

Immunohistochemical study of MUC1, MUC2 and MUC5AC in colorectal carcinoma and review of literature

BACKGROUND

A hallmark of colorectal carcinomas is their ability to secrete mucus. Aberrant expression of mucins and alterations in their glycosylation are associated with the development and progression of malignant diseases. Therefore, mucins can be used as markers of malignancy. Tumor-associated mucins are also used as immunotargets in the treatment of cancer. The present work aimed to study the patterns of expression of MUC1, MUC2 and MUC5AC in colorectal carcinoma using immunohistochemistry and their relationship with site, histological differentiation and stage.

METHODS

Fifty cases of colorectal carcinoma were chosen for the study. The histopathology slides were reviewed and blocks were retrieved. Using manual method, tissue microarray blocks were prepared. Immunostaining for MUC1, MUC2 and MUC5AC was performed on slides cut from the tissue microarray block.

RESULTS

We found that MUC1 expression was upregulated to 39 %, MUC2 expression was downregulated to 43 % and MUC5AC was aberrantly expressed in 24 % of colorectal cancer (CRC). There was a significant correlation between MUC1 positivity and tumor differentiation. As the grade increased from well to moderately differentiated, MUC1 expression increased from 11 % to 55 % (p-value 0.01). There was a statistically significant difference between MUC5AC positivity and grade of tumor (p-value 0.006). The percentage of cases showing MUC5AC expression increased as the stage of disease progressed from 1 to 4. However, there was no significant difference in MUC5AC positivity and stage of CRC (p-value 0.77).

CONCLUSION

We do not find any correlation between tumor stage or site and MUC1, MUC2 or MUC5AC expression. MUC1and MUC5AC expression showed significant correlation with tumor grade.

Clinicopathological features of colon adenocarcinoma in Qazvin, Iran: a 16 year study

BACKGROUND

Colorectal cancer (CRC) was the fourth most commonly diagnosed cancer in Iran between 2000 and 2009, with adenocarcinoma (AC) as the most common histological type. Demographic, topographic and histological variables are important in the epidemiology and biology of cancer. The aim of this study was to investigate clinicopathological features of colon adenocarcinomas in Qazvin, Iran.

MATERIALS AND METHODS

With a retrospective design, patient records of two pathology wards from March 1997 to March 2013 were studied with regard to anatomical location and histological classification. A broader anatomical grouping was also used including distal vs proximal regions and right sided vs left sided tumors. Data were analyzed using T-test and chi-square test.

RESULTS

118 (50.9%) male and 114 (49.1%) female patients were included in the study. Mean age was 57.3±14.7 years, with 29.2% under 50 years. There was no significant gender difference for age at diagnosis. The rectum (56%) and sigmoid colon (25%) were the most frequent anatomical locations. Proximal cases accounted for 18.6% in males and 8.8% in females (p=0.02). AC was more prevalent than other usual types in younger patients. The proportion of proximal cancer was 1.7% in first eight years of the study period vs 12.1% in the second one (p=0.005). A similar trend was also seen in right sided colon cancers (p=0.018).

CONCLUSIONS

Young people are also at risk for the cancer with poor prognosis. Screening programs and weight loss in obese individuals can reduce incidence and complications of CRC.

Prevalence of local recurrence of colorectal cancer at the Iranian Cancer Institute

BACKGROUND

Although a great deal of progress has been made in the management of colorectal cancer in terms of neoadjuvant modalities, surgical techniques and adjuvant therapies, the recurrence of tumors remains an enigmatic complication in patients. A better understanding of colorectal cancer and of factors that lead to recurrence of disease can provide helpful information for designing more effective screening and surveillance methods.

AIM

To investigate the factors that may lead to local recurrence of colorectal cancers.

MATERIALS AND METHODS

The current retrospective case study evaluated 617 patients admitted to the Iranian Cancer Institute (the largest referral cancer center in the country) from 1995 to 2009 with confirmed colorectal cancer. Patients with distant metastasis, or with pathology other than adenocarcinoma and no follow-up, were excluded (175 patients). The remainder (442) included 294 (66.5%) with rectal cancer and 148 (33.5%) with colon cancer. The median duration of follow-up was 26 months.

RESULTS

The total rate of recurrence was 17.4%, comprising 19.6% and 16.3% recurrence rates in colon and rectal cancer, respectively.

CONCLUSIONS

Recurrence of colorectal cancer was significantly correlated to tumor grade (p<0.008).

Pathological stage significantly predicts survival in colorectal cancer patients: a study from two tertiary care centers in India

SUMMARY

Aims: An increase in incidence of early-onset colorectal cancer (EOCRC) in developing countries, including India, is reported recently; however, systematic analyses of clinico-pathological features and disease prognosis has seldom been undertaken. Materials & methods: We studied clinical data pertaining to 1259 colorectal adenocarcinoma patients from two tertiary cancer centers in south India. Results: Approximately 45% of patients were aged below 50 years and poor grade and late-stage tumors were significantly associated with early disease onset. Although tumor grade and stage significantly influenced disease-free survival independently, significant association between survival and age of onset or tumor location was not detected unlike previous observations. Conclusion: Given the sizeable proportion of EOCRC, implementation of the revised Bethesda guidelines may not be tenable in India. More importantly, the previous observation of EOCRC being significantly associated with poor survival could, in part, be due to a higher proportion of advanced-stage tumors.

Segmental versus extended resection for sporadic colorectal cancer in young patients

BACKGROUND AND OBJECTIVES

Guidelines on the management of colon cancer state that extensive colectomy should be "considered" for patients of young age (<50). This study aimed to compare the risk of metachronous cancer, overall recurrence and mortality between segmental and extended colon resections in patients under the age of 50 with sporadic CRC.

METHODS

We performed a retrospective review of patients age <50 undergoing surgery for CRC from 1991 to 2009. Patients were divided into two groups based on extent of resection: segmental versus extended. The primary outcomes analyzed were metachronous tumors, disease recurrence, and overall survival.

RESULTS

Two hundred seventy one patients underwent segmental resection and 30 underwent extended resection. 3.3% in the segmental resection group developed metachronous CRC versus 0% in the extended resection group (P = 0.61). There was no significant difference in the risk of recurrence or mortality for those who underwent a segmental resection compared to those with an extended resection. In a regression model, type of surgery was not an independent risk factor for recurrence or mortality.

CONCLUSIONS

Extended colectomy for sporadic CRC in patients younger than 50 does not improve disease-free or overall survival. Further study to determine if segmental resection is appropriate oncologic treatment is warranted.

Clinicopathological patterns and challenges of management of colorectal cancer in a resource-limited setting: a Tanzanian experience

Background

Colorectal cancer is one of the most common cancers worldwide and its incidence is reported to be increasing in resource-limited countries, probably due to the acquisition of a western lifestyle. However, information regarding colorectal cancer in Tanzania and the study area in particular is limited. This study was conducted in our local setting to describe the clinicopathological pattern of colorectal cancer and highlight the challenging problem in the management of this disease.

Methods

This was a retrospective study of histologically confirmed cases of colorectal cancer seen at Bugando Medical Center between July 2006 and June 2011. Data were retrieved from patients’ files and analyzed using SPSS computer software version 17.0.

Results

A total of 332 colorectal cancer patients were enrolled in the study, representing 4.7% of all malignancies. Males outnumbered females by a ratio of 1.6:1. The median age of patients at presentation was 46 years. The majority of patients (96.7%) presented late with advanced stages. Lymph node and distant metastasis at the time of diagnosis was recorded in 30.4% and 24.7% of cases, respectively. The rectosigmoid region was the most frequent anatomical site (54.8%) involved and adenocarcinoma (98.8%) was the most common histopathological type. The majority of adenocarcinomas (56.4%) were moderately differentiated. Mucinous and signet ring carcinomas accounted for 38 (11.6%)and 15 (4.6%) patients, respectively. Three hundred and twenty-six (98.2%) patients underwent surgical procedures for colorectal cancer. Only 54 out of 321 (16.8%) patients received adjuvant treatment. Postoperative complication and mortality rates were 26.2% and 10.5%, respectively. The overall median duration of hospital stay was 12 days. Only nine out of 297 survivors (3.0%) were available for follow-up at the end of 5 years. Cancer recurrence was reported in 56 of 297 survivors (18.9%). Data on long-term survival were not available as the majority of patients were lost to follow-up.

Conclusions

Colorectal cancer is not uncommon in our environment and shows a trend towards a relative young age at diagnosis and the majority of patients present late with advanced stage. There is a need for screening of high-risk populations, early diagnosis and effective cost-effective treatment and follow-up to improve outcome of these patients.

Young colorectal carcinoma patients do not have a poorer prognosis: a comparative review of 2,426 cases

BACKGROUND

Colorectal cancer (CRC) in "young" patients under 50 years of age is uncommon. There have been conflicting reports regarding both the clinicopathological features of CRC in young patients and prognosis. The aim of this study was to review and compare the clinical characteristics, prognostic factors, and overall survival of patients in three different age groups (40 years and under, 41-50 years, over 50 years of age) and the prognosis of these patients.

METHODS

A total of 2,426 consecutive patients who had undergone surgical resection for sporadic colorectal cancer at Singapore General Hospital in the period from 2000 to 2005 were retrieved from a prospectively collected computer database. There were 73 patients (3.0 %) in Group 1 (40 years old or less), 257 (10.6 %) in Group 2 (41-50 years old), and 2,096 (86.4 %) in Group 3 (>50 years old). Clinicopathological features were assessed using univariate analysis to evaluate significant differences, survival curves were constructed using the Kaplan-Meier method, and multivariate analysis was performed to evaluate the independent prognostic factors.

RESULTS

Young CRC patients tend to present with a higher incidence of mucinous and signet ring cell tumors (Group 1-20.5 %, Group 2-8.2 %, Group 3-6.2 %, p < 0.001) and have more poorly differentiated tumors (Group 1-20.0 %, Group 2-9.7 %, Group 3-7.4 %, p = 0.014). Furthermore, young CRC patients tend to present with regional lymph node metastases (Group 1-65.7 %, Group 2-60.8 %, Group 3-51.0 %, p = 0.001) and distant metastases (Group 1-31.5 %, Group 2-24.1 %, Group 3-19.4 %, p = 0.006). Multivariate analysis reveals, however, that young age is not an independent prognostic factor for cancer-specific survival (CSS) (p = 0.392). Five-year CSS for Group 1 was 56.6 % (95 % confidence interval (CI) 44.8-68.4 %), Group 2 53.8 % (95 % CI 47.3-60.3 %), and Group 3 61.1 % (95 % CI 58.9-63.3 %).

CONCLUSIONS

Although presenting with advanced tumors and with poorer prognostic factors such as presence of mucin and poor histological differentiation, young CRC patients do not have a worse prognosis.

Clinical, endoscopic and pathogical characteristics of early-onset colorectal cancer in Vietnamese

BACKGROUND

The Asia Pacific consensus for colorectal cancer (CRC) recommends that screening programs should begin by the age of 50. However, there have been reports about increasing incidence of CRC at a younger age (i.e. early-onset CRC). Little is known about the features of early-onset CRC in the Vietnamese population.

AIM

To describe the clinical, endoscopic and pathological characteristics of early-onset CRC in Vietnamese.

METHOD

A prospective, cross-sectional study was conducted at the University Medical Center from March 2009 to March 2011. All patients with definite pathological diagnosis of CRC were recruited. The early-onset CRC group were analyzed in comparison with the late-onset (i.e.≥50-year-old) CRC group.

RESULTS

The rate of early-onset CRC was 28% (112/400) with a male-to-female ratio of 1.3. Some 22.3% (25/112) of the patients only experienced abdominal pain and/or change in bowel habit without alarming symptoms, 42.9% (48/112) considering their symptoms intermittent. The rate of familial history of CRC in early-onset group was significantly higher that of the late-onset group (21.4% versus 7.6%, p<0.001). The distribution of CRC lesions in rectum, distal and proximal colon were 51.8% (58/112), 26.8% (30/112) and 21.4% (24/112), respectively; which was not different from that in the late-onset group (χ2, p=0.29). The rates for poorly differentiated tumors were also not significantly different between the two groups: 12.4% (14/112) versus 8.3% (24/288) (χ2, p=0.25).

CONCLUSION

A high proportion of CRC in Viet Nam appear at an earlier age than that recommended for screening by the Asia Pacific consensus. Family history was a risk factor of early-onset CRC. Diagnosis of early-onset CRC needs more attention because of the lack of alarming symptoms and their intermittent patterns as described by the patients.

Anatomical distribution of colorectal carcinoma in Iran: a retrospective 15-yr study to evaluate rightward shift

BACKGROUND

Although more than two third of colorectal cancers are localized on the left side, recent studies suggest a right ward shift in anatomical distribution with increase in proximal colon cancers. The aim of the present study was to determine the anatomical distribution of colorectal cancer in a referral center over a 15 year period.

METHOD

Records of patients who underwent colectomy in the Cancer Institute of Iran from 1994 to 2009 were retrieved. Data including anatomical localization, year of diagnosis, patient age and gender, tumor histology and differentiation, and disease stage were extracted. Tumors located from the cecum to the distal transverse colon were classified as right side and those occurring from the splenic flexure to the descending colon as left-sided. Cancer of rectum and recto-sigmoid junction were considered as rectal cancers.

RESULTS

A total of 442 patients including 220 (49/8%) men and 222 (50/2%) women with mean age 53 were included. Most patients were in stages II and III (47.1% and 33% respectively). There were 157 (35.5 %) colon cancers and 285 (64.5%) rectal cancers. 43.3% of the colon cancers were right sided and 56.7% were left sided. There was no statistically significant increase in right sided cancer during the period of the study. There were no significant differences in age at diagnosis, gender, grade and stage of tumor between the right and the left sided cancers.

CONCLUSION

No proximal shift over time was identified in our study.

Metastatic signet ring colon cancer in a Caribbean young adult and review of the literature

Colorectal cancer is the third most common neoplasm diagnosed in the USA, with less than 3% of patients younger than 40 years. Although most of the literature indicates that younger patients present with a higher stage and grade of cancer, mortality is not clearly correlated. Furthermore, the literature pertaining to colorectal cancer in the nonwhite youth is limited. In this case report, we report a case of aggressive colorectal cancer metastasizing in a young Afro-Caribbean woman with no known risk factors. The aim of this report is to raise awareness of this entity in the younger population, particularly in Afro-Caribbeans, which remains a highly understudied group compared with the rest of the US population.

The impact of age on outcome after surgery for colorectal adenocarcinoma

INTRODUCTION

The incidence of colorectal cancer (CRC) increases with age. The aim of this study was to investigate the impact of age and age-related factors on post-operative mortality and survival following CRC resections.

METHODS

A prospectively collected database of 459 CRC resections was analysed.

RESULTS

The mean age of the patients was 70 years (range: 25-95 years) and 54% were male. The relative proportion of female patients increased with age so that for patients aged over 77 more women were treated than men. The probability of undergoing an emergency resection (25%) did not change with age. In older patients the proportion of rectal cancers resected decreased and the proportion of hemicolectomies and Hartmann's operations performed increased. The 30-day mortality rate was 4% after elective and 11% after emergency resections. Most deaths were caused by medical complications, reflecting increased co-morbidity in the elderly. Post-operative mortality was 1% in patients under the age of 59. This increased by 3 percentage points every 10 years after elective resections and by 8 percentage points every 10 years after emergency resections. CRC-specific survival was independent of age whereas overall survival decreased so the likelihood of dying from CRC decreased with age: at age 50 half the deaths were from CRC, at age 70 a third and at age 80 a quarter.

CONCLUSIONS

CRC stage and the probability of presenting as an emergency did not change with age but older patients were more likely to be female and have colon cancer. Post-operative mortality progressively increased with age. Most deaths were caused by medical complications, reflecting increased co-morbidity. Older patients were less likely to die from CRC.

Epidemiological and clinical characteristics of colorectal cancer in Huidong District, Guangdong Province, over the past 10 years

AIM: To analyze the epidemiological and clinical characteristics of colorectal cancer in Huidong District, Guangdong Province, over the past 10 years.

METHODS: Data were collected from all consecutive patients receiving colonoscopy at our hospital during the past 10 years. The epidemiological data, clinical presentations, endoscopic findings, and pathohistological characteristics of patients with colorectal cancer were reviewed and analyzed retrospectively.

RESULTS: A total of 10 532 patients received colonoscopy from 2001 to 2010, and of them 853 cases of colorectal cancer were identified by histological assessment. The detection rate of colorectal cancer rose from 8.0% in the first 5-year period to 8.2% in the second five-year period. The median age of patients with colorectal cancer in the second five-year period was older than that in the first five-year period (65 years vs 59 years). The rectum is the most frequent site for colorectal cancer (55.0%), while hematochezia is the most common symptom (56.0%). The detection rate of right-sided colonic cancer in the second five-year period was significantly higher than that in the first five-year period (19.2% vs 15.1%, P < 0.05). Histologically, adenocarcinoma was the most frequent histological subtype (65.5%).

CONCLUSION: The onset age of patients with colorectal cancer is becoming older in Huidong District, Guangdong Province. The rectum remains the most frequent site for colorectal cancer. The shift in site of colonic cancer toward the right has occurred.

High frequency of genes' promoter methylation, but lack of BRAF V600E mutation among Iranian colorectal cancer patients

Gene silencing due to DNA hypermethylation is a major mechanism for loss of tumor suppressor genes function in colorectal cancer. Activating V600E mutation in BRAF gene has been linked with widespread methylation of CpG islands in sporadic colorectal cancers. The aim of the present study was to evaluate the methylation status of three cancer-related genes, APC2, p14ARF, and ECAD in colorectal carcinogenesis and their association with the mutational status of BRAF and KRAS among Iranian colorectal cancer patients. DNA from 110 unselected series of sporadic colorectal cancer patients was examined for BRAF V600E mutation by PCR-RFLP. Promoter methylation of genes in tumors was determined by methylation specific PCR. The frequency of APC2, E-CAD, and p14 methylation was 92.6%, 40.4% and 16.7%, respectively. But, no V600E mutation was identified in the BRAF gene in any sample. No association was found in cases showing epigenetic APC, ECAD, and p14 abnormality with the clinicopathological parameters under study. The association between KRAS mutations and the so called methylator phenotype was previously reported. Therefore, we also analyzed the association between the hot spot KRAS gene mutations in codons of 12 and 13 with genes' promoter hypermethylation in a subset of this group of patients. Out of 86 tumors, KRAS was mutated in 24 (28%) of tumors, the majority occurring in codon 12. KRAS mutations were not associated with genes' methylation in this tumor series. These findings suggest a distinct molecular pathway for methylation of APC2, p14, and ECAD genes from those previously described for colorectal cancers with BRAF or KRAS mutations.

Colorectal carcinoma in young adults: a retrospective study on Indian patients: 2000-2008

AIM

To highlight an increased incidence of colorectal cancer (CRC) amongst young Indian adults.

METHOD

A retrospective study of 305 cases of CRC admitted to SSKM Hospital, Kolkata, India during 2000-2008 was carried out.

RESULTS

The ratio (0.64) of under-40 to above-40 CRC patients reported in this study is comparable to those from premier Oncology Centers in India (∼0.52) and is higher than those in the Indian National Cancer Registry (∼0.20) and international average (0.07). Distinctive tumour characteristics in younger patients including left-sided lesion (69.7%), presentation at an advanced (III/IV) stage (60%), poor histological differentiation (50%) and predominance of mucin-secreting adenocarcinoma (80%) are similar to those reported in the international literature. Some features are suggestive of hereditary non polyposis colorectal cancer syndrome, which may be a possible reason for the high proportion of young CRC patients.

CONCLUSION

A high index of suspicion for CRC among young Indian adults is necessary.

Trend of colorectal cancer in Hong Kong: 1983-2006

BACKGROUND AND AIM

The incidence of colorectal cancer (CC) is increasing in many Asian countries, but decreasing in western countries. The present study examined the local incidence of CC in the past few decades.

METHODS

A population based study, using data from Hong Kong (HK) Cancer Registry, was carried out to examine the trends of CC in different age groups in HK. Comparison with other countries was made.

RESULTS

The crude rate of CC in HK increased from 29.6/100,000 in 1983 to 57.1/100,000 in 2006. Age standardized rate (ASR) increased by less than 20%. It was markedly smaller than the 190% increase in crude rate. ASR progressively increased in males. In females, ASR peaked in 1994 and declined in the last decade. In most countries, the risk of CC was higher and increasing in males, but stable or decreasing in females. With respect to age, increasing risk was noted in males above 60 years old and females above 70 years old. However, a declining rate was noted in those below 50 years old. The decrease was over 40% in the 30-34 years group over the past two decades.

CONCLUSIONS

Increasing incidence of CC in HK was mostly in the older and male population, but not in the younger age group.

Colorectal cancer distribution in 220 Indian patients undergoing colonoscopy

AIM

Colorectal cancer is one of the major cancers in the developed world. The incidence of colorectal cancer is low in India. The aim of the present study was to describe the anatomical distribution and age at diagnosis of colorectal cancer in India.

METHODS

Retrospective descriptive analysis of anatomical distribution, age at diagnosis and demography of 220 cases (149 [67.7%] men) of adenocarcinoma of the colon or rectum diagnosed at colonoscopy over a period of five years.

RESULTS

The mean age at diagnosis was 58.4 years (SD 13.3; range 23-85 years). Twenty-eight (12.7%) cases were below the age of 40 years. The majority (31.8%) cases were aged between 61-70 years. Most of the tumors (n=163, 74%) were located distal to the splenic flexure. Multivariate logistic regression analysis showed that bleeding per rectum (OR 2.8; 95% CI 1.2-6.2) was associated with distal cancer, and palpable mass (OR 3.9; 95% CI 1.7-8.6) was associated with proximal cancer.

CONCLUSIONS

Almost one-third of the colorectal cancers in this series occurred in the seventh decade and were located distal to the splenic flexure.

Changes on the disease pattern of primary colorectal cancers in Southern China: a retrospective study of 20 years

PURPOSE

Some changes on the disease pattern of colorectal cancer (CRC) have occurred in some Asian countries recently. However, nothing is known about it in China lately. The present study is to determine whether there are any changes on the disease pattern of CRC in Southern China.

PATIENTS AND METHODS

Data were collected from all consecutive patients accepting colonoscopy in our endoscopy center during the last 20 years. The sociodemographic data, clinical presentations, endoscopic descriptions, and histological subtypes of patients confirmed as CRC by pathology were analyzed retrospectively.

RESULTS

A total of 37,578 patients accepted colonoscopy from 1987 to 2006, in which 2,876 patients were diagnosed as CRC. The median age of patients in the 2nd decade (1997-2006; 62 years) was getting older than the 1st decade (1987-1996; 58 years; P = 0.043). Hematochezia was the most frequent symptom (55.8%), while rectum was the most common site distribution of CRC (51.0%). The incidence of right-sided colonic cancers in the 2nd decade (21.0%) was higher than the 1st decade (17.3%; P = 0.0314). Histologically, adenocarcinoma was the most common (92.4%), of which moderately differentiated tumors were more frequent (67.7%). CRCs with high-grade malignancy were more likely to occur in the 1st decade (P < 0.0001).

CONCLUSIONS

Rectum remains the most common site of CRC in southern China. But a rightward shift in the site distribution has occurred and patients are getting older. Tumors with high-grade malignancy have the tendency to decrease.

Rectal cancer in young adults: a series of 102 patients at a tertiary care centre in India

OBJECTIVE

Rectal cancer in young patients is uncommon. There is little information on rectal cancer in young adults in India. The aim of this study was to determine the relative incidence of rectal cancer in young patients in India and identify any differences in histological grade and pathological stage between younger and older cohorts.

METHOD

All adult patients presenting at a tertiary colorectal unit with primary rectal adenocarcinoma between September 2003 and August 2007 were included. Patients were divided into two groups: 40 years and younger, and older than 40 years. Details regarding patient demographics, preoperative assessment, management and tumour grade and stage were obtained from a prospectively maintained database.

RESULTS

One hundred and two of 287 patients (35.5%) were 40 or younger at presentation. Younger patients were more likely to present with less favourable histological features (52.0% vs 20.5% (P < 0.001)) and low rectal tumours (63.0% vs 50.0%) (P = 0.043), but were equally likely to undergo curative surgery compared to the older group (P = 0.629). Younger patients undergoing surgery had a higher pathological T stage (T0-2 18.9%, T3 62.3%, T4 19.7% vs 34.5%, 56.0%, 9.5%) (P = 0.027) and more advanced pathological N stage (N0 31.1%, N1 41.0%, N2 27.9% vs 53.4%, 26.7%, 17.2%) (P = 0.014).

CONCLUSION

The relative number of young patients with rectal cancer in this Indian series is higher than figures reported in western populations. The reasons for this are not clear. The histopathological features of rectal tumours in young patients in this study are consistent with similar studies in Western populations.

Colorectal carcinoma in Lagos and Sagamu, Southwest Nigeria: A histopathological review

AIM: To study the frequency, gender and age distribution as well as pathological characteristics of colorectal carcinoma (CRC) in Lagos and Sagamu in SW Nigeria.

METHODS: This is a retrospective pathological review of histologically diagnosed CRC from 5 laboratories in Lagos & Sagamu. The clinical data, such as age, sex and clinical summary were extracted from demographic information. Cases of anal cancer were excluded from this study.

RESULTS: There were 420 cases (237 males and 183 females) of CRC. It peaked in the 60-69 year age group (mean: 50.7; SD: 16.2), M:F ratio 1.3:1 and 23% occurred below 40 years. The majority was well to moderately differentiated adenocarcinoma 321 (76.4%), mucinous carcinoma 45 (10.7%) and signet ring carcinoma 5 (1.2%), and more common in patients under 40 years compared to well differentiated tumors. The recto-sigmoid colon was the most common site (58.6%). About 51% and 34% of cases presented at TNM stages II and III, respectively.

CONCLUSION: CRC is the commonest malignant gastrointestinal (GIT) tumor most commonly located in the recto-sigmoid region. The age and sex prevalence and histopathological features concur with reports from other parts of the world.

Clinical features of colorectal cancer in Iran: a 15-year review

OBJECTIVE

The increasing frequency of colorectal cancer in Asian countries, which have traditionally had a lower incidence than populations in developed countries, and a lower age of onset in Iran led us to perform a study on patients with colorectal cancer to investigate the clinical features of colorectal cancer in Iranians.

METHODS

We studied 977 consecutive cases of colorectal cancer in terms of age, gender, and anatomic location during a 15-year period (1989-2004). The patients were hospitalized in three referral hospitals affiliated to Shahid Beheshti Medical University in Tehran, Iran. Related data were extracted from the patients' medical records and processed using SPSS ver. 12. Most of our patients (251 cases or 25.6%) were between 60 and 69 years of age. We recorded 534 men (54.3%) and 443 women (45.7%). A total of 36% of patients were between 40 and 59 years and 306 patients (31.32%) had rectal cancer.

RESULTS

The highest frequency of colorectal cancer in our study belonged to an age group a decade younger than the range mentioned in the literature for populations in developed societies.

CONCLUSION

Regarding similar studies, it seems reasonable to adopt screening a decade earlier for Iranian patients.

Clinical and pathologic outcomes of colorectal cancer in a multi-ethnic population

BACKGROUND & AIMS

The influence of birthplace on the clinical and pathologic outcomes of colorectal cancer (CRC) in Australia is unknown. Addressing inequalities in health care provision in immigrant groups may improve the overall quality of CRC care.

METHODS

The South Western Sydney Colorectal Tumour Group registry prospectively collects data on new patients with CRC from a population of 800,000. Survival data were cross-linked with the New South Wales population death registry.

RESULTS

From 1997 to 2004 there were 1496 patients (55% males) who were recruited and grouped according to country of birth: Australia, 64%; Southern Europe, 19%; Asia, 12%; and the Middle East, 5%. Significant heterogeneity in CRC characteristics was found, especially in Asians. Compared with Australians, Asians were diagnosed at a younger age (median age, 64 vs 70 y; P < .001, 25.6% were younger than 50 years vs 9.5%; P < .001), had fewer poorly differentiated cancers (8.9% vs 17.7%; P = .004), and fewer metastatic cancers (12.1% vs 21.0%; P = .001). Being Asian-born was associated with improved overall survival independent of age, emergency surgery, grade, and stage (hazard ratio, 0.66; 95% confidence interval, 0.47-0.93; P = 0.02). CRC screening was especially low among Asian- and Middle Eastern-born patients. Complications and treatment were not affected by birthplace, indicating no differences in the provision or acceptance of care based on birthplace.

CONCLUSIONS

Despite an equitable distribution of resources, we found significant heterogeneity in presentations and outcomes according to birthplace, with improved survival in Asian-born patients. The lower rates of screen-detected CRC in Asian- and Middle Eastern-born patients and their younger ages at diagnosis indicate that targeted screening strategies may need to be implemented.

Impact of BRAF, MLH1 on the incidence of microsatellite instability high colorectal cancer in populations based study

We have identified an alternative pathway of tumorigenesis in sporadic colon cancer, involving microsatellite instability due to mismatched repair methylation, which may be driven by mutations in the BRAF gene (V600E). Colorectal cancer (CRC) is the most common cancer in the world, and African Americans show a higher incidence than other populations in the United States. We analyzed sporadic CRCs in Omani (of African origin, N = 61), Iranian (of Caucasian origin, N = 53) and African American (N = 95) patients for microsatellite instability, expression status of mismatched repair genes (hMLH1, hMSH2) and presence of the BRAF (V600E) mutation. In the Omani group, all tumors with BRAF mutations were located in the left side of the colon, and for African Americans, 88% [7] of tumors with BRAF mutations were found in the right side of the colon. In African Americans, 31% of tumors displayed microsatellite instability at two or more markers (MSI-H), while this rate was 26% and 13% for tumors in the Iranian and Omani groups, respectively. A majority of these MSI-H tumors were located in the proximal colon (right side) in African American and Iranian subjects, whereas most were located in the distal colon (left side) in Omani subjects. Defects in hMLH1 gene expression were found in 77% of MSI-H tumors in both African Americans and Iranians and in 38% of tumors in Omanis. BRAF mutations were observed in all subjects: 10% of tumors in African Americans (8/82), 2% of tumors in Iranians (1/53), and 19% of tumors in Omanis (11/59). Our findings suggest that CRC occurs at a younger age in Omani and Iranian patients, and these groups showed a lower occurrence of MSI-H than did African American patients. Our multivariate model suggests an important and significant role of hMLH1 expression and BRAF mutation in MSI-H CRC in these populations. The high occurrence of MSI-H tumors in African Americans may have significant implications for treatment, since patients with MSI-H lesions display a different response to chemotherapeutic agents such as 5-fluorouracil.

Clinical predictors of colorectal polyps and carcinoma in a low prevalence region: Results of a colonoscopy based study

AIM: To estimate the prevalence of colorectal cancer (CRC) in patients with long lasting colonic symptoms undergoing total colonoscopy; and to establish clinical features predicting its occurrence.

METHODS: This prospective study was carried out in Imam Hospital, Tabriz University of medical sciences, Iran. Continuous patients with long lasting lower gastrointestinal tract symptoms who had the criteria of a colonoscopy were included. The endoscopist visualized the caecum documented by a photo and/or a specimen from terminal ileum.

RESULTS: Four hundred and eighty consecutive symptomatic patients [mean age (SD): 42.73 (16.21)] were included. The prevalence of colorectal neoplasia was 15.3% (34 subjects) and 37.7% (181 subjects) had a completely normal colon. Adenomatous polyps were detected in 56 (11.7%) patients, in 12.3% of men and 10.9% of women. The mean age of the patients with a polyp was significantly higher than the others (49.53 ± 14.16 vs 41.85 ± 16.26, P = 0.001). Most of the adenomatous polyps were left sided and tubular; only 22.5% of polyps were more than 10 mm. Cancer was detected in 16 (3.6%) of our study population, which was mostly right sided (57.2%). The mean age of patients with cancer was significantly higher than the others (60.25 ± 8.26 vs 42.13 ± 16.08, P < 0.005) and higher than patients with polyps [60.25 (8.26) vs 49.53 (1.91) (P < 0.0005)]. None of the symptoms (diarrhea, abdominal pain, rectal bleeding, constipation, altering diarrhea and constipation, history of cancer, known irritable bowel disease, history of polyp and fissure or family history of cancer) were predictors for cancer or polyps, but the age of the patient and unexplained anemia independently predicted cancer.

CONCLUSION: Less advanced patterns and smaller sizes of adenomas in Iran is compatible with other data from Asia and the Middle East, but in contrast to western countries. Prevalence of colonic neoplasia in our community seems to be lower than that in western population. Colonic symptoms are not predictors for polyps or cancer but unexplained anemia and elder age can predict CRC.