Colorectal cancer incidence in 5 Asian countries by subsite: An analysis of Cancer Incidence in Five Continents (1998-2007)

Numb Chin Syndrome as the Initial Presentation of Mandibular Metastasis of Colorectal Cancer: A Case Report

Numb chin syndrome (NCS) is hypesthesia of the mandible and lower lip caused by damage to the inferior alveolar or mandibular nerves, commonly due to dental treatment or osteomyelitis, but occasionally caused by malignant tumors. We report the case of a male in his 60s. He came to our hospital with a chief complaint of mandibular pain and paresthesia in the right side of the mental region. He had noticed swelling of the left mandible one month before the initial visit and strong hypesthesia of the right side of the mental region one week before the initial visit. Panoramic radiographs showed slight osteosclerosis of the left side mandible at the initial visit. Blood tests showed only a slight inflammatory reaction. The diagnosis of mandibular osteomyelitis and numb chin syndrome was made, and a contrast-enhanced CT scan was performed to investigate the possibility of neoplastic lesions, but no obvious cause was found. Osteosclerosis was minimal. A tissue biopsy was recommended, but the patient did not consent. Considering the possibility of NCS due to a hematologic disorder, the patient was referred to a hematologist, but no cause could be identified at the initial visit. With time, the markedly severe pain worsened, and the possibility of a neoplastic lesion was again suspected. Blood tests were performed, which revealed abnormally high levels of CA19 and CEA. He consulted a gastroenterologist, who found a tumor in the ileocecal region on contrast-enhanced CT, and multiple systemic metastases were found on a PET-CT scan the next day. Systemic chemotherapy was administered for multiple metastatic unresectable colorectal cancer (cT4N1aMc2 stage IVc).

Global Prevalence of Suicide in Patients With Cancer: A Systematic Review and Meta-Analysis

AIM

Given that patients with cancer may commit suicide due to physical and mental problems, the present study objectives were to identify particular risk factors of different subgroup of patients including type of cancer, gender, age, type and time of suicide, and geographical region to facilitate early care and psychosocial support.

METHODS

A comprehensive review of databases including Embase, Scopus, PubMed, and Web of Science was conducted for original articles published in English from January 2000 to March 2022. It is based on the PRISMA checklist.

RESULTS

After reviewing 69 articles selected from 15 countries, the total prevalence rate of suicide among 34,157,856 patients with cancer was estimated 67,169, at 0.013 (95% CI, 0.008-0.021). The highest suicide prevalence was related to gastrointestinal cancer, estimated at 0.204 (95% CI, 0.161-0.255). A gender-based meta-analysis showed that the prevalence of suicide/suicidal ideation was higher among men, estimated at 0.013 (95% CI, 0.008-0.023) compared with women, at 0.006 (95% CI, 0.002-0.017).

CONCLUSION

Based on study results, suicide-prevention strategies should be aimed at patients younger than 40 years of age to effectively resolve their mental health disorders and promote their self-efficacy in successful management of the disease.

Gene-environment interactions in birth defect etiology: Challenges and opportunities

Birth defects are relatively common congenital outcomes that significantly impact affected individuals, their families, and communities. Effective development and deployment of prevention and therapeutic strategies for these conditions requires sufficient understanding of etiology, including underlying genetic and environmental causes. Tremendous progress has been made in defining the genetic basis of familial and syndromic forms of birth defects. However, the majority of birth defect cases are considered nonsyndromic and thought to result from multifactorial gene-environment interactions. While substantial advances have been made in elucidating the genetic landscape of these etiologically complex conditions, significant biological and technical constraints have stymied progress toward a refined knowledge of environmental risk factors. Defining specific gene-environment interactions in birth defect etiology is even more challenging. However, progress has been made, including demonstration of critical proofs of concept and development of new conceptual and technical approaches for resolving complex gene-environment interactions. In this review, we discuss current views of multifactorial birth defect etiology, comparing them with other diseases that also involve gene-environment interactions, including primary immunodeficiency and cancer. We describe how various model systems have illuminated mechanisms of multifactorial etiology and these models' individual strengths and weaknesses. Finally, suggestions for areas of future emphasis are proposed.

A new fat-dissociation method to detect lymph nodes in colorectal cancer: a prospective randomized study

Histological examination of the lymph nodes (LNs) is crucial to determine the colorectal cancer (CRC) stage. We previously reported a new fat-dissociation method (FM) to detect LNs from surgically resected mesentery. This study aimed to examine the effectiveness of FM compared with that of conventional palpation method (PM) in CRC. This single-center, open-label, randomized controlled study was performed at Osaka International Cancer Institute in Japan in 2014. Randomization was performed using a computer-generated permuted-block sequence. Patients were stratified by surgical procedures and the LN dissection area. The primary endpoint was the time required for LN identification. The secondary endpoint was the number of LNs and 5-year cancer-specific survival. The 130 enrolled patients were randomly assigned in a 1:1 ratio to the FM and the PM groups. LN identification times were 45 (range 15-80) and 15 (range 7-30) minutes in the PM and the FM groups, respectively (P < 0.001). In the PM group, body mass index and identification time were correlated (P = 0.047). The number of LN which could be examined pathologically was 16 (range 2-48) and 18 (range 4-95) in the PM and FM groups, respectively (P = 0.546). In right-sided CRC, the number of LNs was higher in the FM group than in the PM group (P = 0.031). Relapse-free survival rates and cancer-specific survival rates did not differ between the groups. In conclusion, FM reduced the time required for LN detection without reducing the number of detected LNs, making it is a useful method to detect LNs in surgical specimens.

Tumour predisposition and cancer syndromes as models to study gene-environment interactions

Cell division and organismal development are exquisitely orchestrated and regulated processes. The dysregulation of the molecular mechanisms underlying these processes may cause cancer, a consequence of cell-intrinsic and/or cell-extrinsic events. Cellular DNA can be damaged by spontaneous hydrolysis, reactive oxygen species, aberrant cellular metabolism or other perturbations that cause DNA damage. Moreover, several environmental factors may damage the DNA, alter cellular metabolism or affect the ability of cells to interact with their microenvironment. While some environmental factors are well established as carcinogens, there remains a large knowledge gap of others owing to the difficulty in identifying them because of the typically long interval between carcinogen exposure and cancer diagnosis. DNA damage increases in cells harbouring mutations that impair their ability to correctly repair the DNA. Tumour predisposition syndromes in which cancers arise at an accelerated rate and in different organs - the equivalent of a sensitized background - provide a unique opportunity to examine how gene-environment interactions influence cancer risk when the initiating genetic defect responsible for malignancy is known. Understanding the molecular processes that are altered by specific germline mutations, environmental exposures and related mechanisms that promote cancer will allow the design of novel and effective preventive and therapeutic strategies.

The Utility of Gastrointestinal Endoscopic Examination Versus Positron Emission Tomography-Computed Tomography in the Detection of Second Primary Lesions in Korean Patients With Head and Neck Cancer

OBJECTIVE

Head and neck cancer often accompany a synchronous secondary primary lesion in the digestive tract. The aim of this study was to compare detection rates between positron emission tomography-computed tomography (PET-CT) and esophagogastroduodenoscopy (G-fiber) or colonoscopy (C-fiber) in the initial staging and to analyze risk factors for premalignant, malignant, and total synchronous secondary primary lesions.

METHODS

A total of 739 patients with head and neck cancer who underwent PET-CT, G-fiber, or C-fiber were analyzed retrospectively.

RESULTS

Positron emission tomography-CT did not definitely detect any premalignant synchronous secondary primary lesions (0 [0%] of 739) but definitely detected 10 malignant synchronous secondary primary lesions (10 [1.35%] of 739). Esophagogastroduodenoscopy or C-fiber detected all 20 premalignant synchronous secondary primary lesions (20 [2.71%] of 739) and all 37 malignant synchronous secondary primary lesions (37 [5.00%] of 739). The patients with nasopharynx cancer tended to have premalignant synchronous secondary primary lesions (odds ratio [OR]: 3.793; 95% CI: 1.414-10.171; P = .008). Those with distant metastasis tended to have premalignant (OR: 4.743; 95% CI: 1.508-14.916; P = .009), malignant (OR: 3.803; 95% CI: 1.486-9.731; P = .005), and total synchronous secondary primary lesions (OR: 2.753; 95% CI: 1.159-6.538; P = .022).

CONCLUSIONS

Premalignant or malignant synchronous secondary primary lesions that were not definitely detected by PET-CT could be found in the endoscopic examination.

A Comprehensive Repertoire of Transfer RNA-Derived Fragments and Their Regulatory Networks in Colorectal Cancer

To provide systematic insight into the composition and expression of transfer RNA (tRNA) derivatives transcriptome in colorectal cancer (CRC). tRNA derivatives expression profiles in three pairs of CRC and adjacent normal colon tissues were performed by tRNA-derived small RNA fragments (tRFs) and tRNA halves (tiRNA) sequencing, and microarray data of transcriptomes from CRC and paired controls were retrieved from Gene Expression Omnibus database. The differentially expressed tRFs and tiRNAs and differentially expressed genes between CRC and paired normal samples were screened. The functional regulations between tRF and tiRNA and gene were identified. A total of 60 upregulated and 48 downregulated tRNA derivatives and 7373 upregulated and 12,138 downregulated messenger RNA (mRNA) were identified. The tRF and tiRNA-gene regulatory modules were constructed by analyzing computational tRF and tiRNA-target predictions and inverse expression relationships between tRF and tiRNAs and mRNA. Gene ontology and Kyoto Encyclopedia of Genes and Genomes pathway annotation showed that the function of targets of tiRNA-Tyr-GTA was mainly enriched in negative regulation of epithelial cell apoptotic process and peroxisome proliferator activated-receptors (PPAR) signaling pathway. Cellular response to monoamine stimulus and inflammatory bowel disease was enriched in function of tiRNA-Val-CAC. Two functions, including negative regulation of c-Jun N-terminal kinase (JNK) cascade and choline metabolism in cancer, were enriched in tRF-Gln-CTG. The function of mesenchymal to epithelial transition was enriched in tRF-Leu-TAG. For the first time to our knowledge, our study provided a landscape of tRNA derivatives expression profiles in CRC. Further tRF and tiRNA-gene regulatory modules construction explored the potential functions related to these tRNA derivatives in the pathogenesis of CRC.

Colorectal cancer in the United States and a review of its heterogeneity among Asian American subgroups

Colorectal cancer is the third most common cancer in the United States. Established risk factors include older age, unhealthy lifestyle (high consumptions of red/preserved meat, low consumptions of fruit and vegetables, smoking, high alcohol consumption, and lack of physical activities), personal and family medical histories and low socioeconomic status (low insurance coverage, education and income). Asian American subgroups vary significantly in terms of culture, socioeconomic status, and health behaviors, yet most registries and researches aggregate all Asian Americans as one group. In this review, we summarized and compared colorectal cancer incidence among different Asian American subgroups, and to explore the reasons behind the heterogeneity. Based on limited literatures, we found that Japanese Americans have the highest colorectal cancer incidence among all Asian Americans. The incidence is decreasing among most Asian American subgroups except for Korean Americans. Such heterogeneity is influenced by lifestyle factors related to the country of origin and the United States, as well as colorectal cancer screening.

Pattern, Stage, and Time of Recurrent Colorectal Cancer After Curative Surgery

Surgery remains the mainstay of curative treatment for colorectal cancer (CRC). Despite curative surgery, some patients experience cancer recurrence. However, the pattern, stage, and time of recurrent disease (RD) remain unknown. We aimed to determine the pattern and stage of RD after curative open and laparoscopic surgery for CRC. Databases were searched using selected keywords for clinical studies that analyzed the pattern, stage, and time of RD from CRC. A systematic protocol was used for data extraction, data synthesis, and interpretation of results. Of 455 publications retrieved from databases, 9 clinical studies were selected for this systematic review. There is substantial evidence that pulmonary recurrence is most commonly associated with rectal tumors, and multisite RD appears more frequently with right-sided CRC. RD from colon cancers predominantly appears early in liver, while recurrences from rectal cancer appear late in lungs. Approximately 30% to 50% of RD after curative resection of CRC occurs within the first 2 years; however, median time to recurrence is gradually increasing, particularly for patients with rectal cancers. Advanced primary CRC is significantly correlated with more locoregional and distant RD, with worse disease-free survival. There is a decrease in the 5-year incidence of RD that is associated with prolongation of time of RD for both locoregional and metastatic disease. The duration and design of postoperative follow-up protocols for recurrences from CRC should be tailored to site and stage of primary tumor, as rectal cancers demand longer surveillance times than colon cancer.

Resection depth and layer of cold snare polypectomy versus endoscopic mucosal resection

BACKGROUND

Cold snare polypectomy (CSP) has not undergone sufficient histopathological evaluation. This study aimed to clarify the histopathological features of CSP specimens, including resection depth and layer, as compared with endoscopic mucosal resection (EMR).

METHODS

Polyps were recruited retrospectively. Sessile, semi-pedunculated, and 0-IIa polyps of ≤ 9 mm were selected by propensity score matching and classified as either a complete resection or one with an unevaluable/positive (X/+) margin. Resection depth and layer were estimated and the risk factors for an X/+ margin were evaluated.

RESULTS

A total of 1072 polyps were enrolled. After matching, 184 polyp pairs were selected. An X/+ margin was seen in 105/184 (57%) vs. 70/184 (38%) CSP vs. EMR specimens (p < 0.001): specimen damage was 53/184 (29%) vs. 30/184 (16%) (p < 0.01) and vertical margin (VM) X/+ was 11/184 (6%) vs. 2/184 (1%) (p < 0.05). Among 193 completely resected specimens, resection depth from the muscularis mucosae in CSP vs. EMR was 76 vs. 338 µm (p < 0.001) and resection layer was the submucosa in 7/79 (9%) vs. 105/114 (92%) (p < 0.001). In multivariate analysis, CSP was a risk factor for procedure-associated VMX/+ [odds ratio (OR) 6.80, 95% confidence interval (CI) 1.33-34.69, p < 0.05]. Sessile serrated adenoma/polyp (SSA/P) was a risk factor for VMX/+ margin in CSP specimens (OR 58.36, 95% CI 7.45-456.96, p < 0.001).

CONCLUSIONS

SSA/P and colorectal cancer may not be suitable for CSP adoption.

The Vagus Nerve Can Predict and Possibly Modulate Non-Communicable Chronic Diseases: Introducing a Neuroimmunological Paradigm to Public Health

Global burden of diseases (GBD) includes non-communicable conditions such as cardiovascular diseases, cancer and chronic obstructive pulmonary disease. These share important behavioral risk factors (e.g., smoking, diet) and pathophysiological contributing factors (oxidative stress, inflammation and excessive sympathetic activity). This article wishes to introduce to medicine and public health a new paradigm to predict, understand, prevent and possibly treat such diseases based on the science of neuro-immunology and specifically by focusing on vagal neuro-modulation. Vagal nerve activity is related to frontal brain activity which regulates unhealthy lifestyle behaviors. Epidemiologically, high vagal activity, indexed by greater heart rate variability (HRV), independently predicts reduced risk of GBD and better prognosis in GBD. Biologically, the vagus nerve inhibits oxidative stress, inflammation and sympathetic activity (and associated hypoxia). Finally, current non-invasive methods exist to activate this nerve for neuro-modulation, and have promising clinical effects. Indeed, preliminary evidence exists for the beneficial effects of vagal nerve activation in diabetes, stroke, myocardial infarction and possibly cancer. Thus, we propose to routinely implement measurement of HRV to predict such GBD in populations, and to test in randomized controlled trials effects of non-invasive vagal nerve activation on prevention and treatment of GBD, reflecting possible neuro-modulation of health.

Mapping the cancer-specific QLQ-C30 onto the generic EQ-5D-5L and SF-6D in colorectal cancer patients

INTRODUCTION

Economic evaluation of healthcare interventions usually needs accurate data on utility and health-related quality-of-life scores. The aim of this study is to map QLQ-C30 scale score onto EQ-5D-5L and SF-6D utility values in colorectal cancer (CRC) patients.

METHODS

EQ-5D-5L, SF-6D, and QLQ-C30 were completed by 252 patients with CRC who were referred to three cancer centers in Tehran between May and September 2017. Moreover, OLS, Tobit, and CLAD models were used to predict EQ-5D-5L and SF-6D values. The goodness of fit of models was evaluated using Pred R² and Adj R². In addition, their predictive performance was assessed by MAE, RMSE, ICC, MID, and Spearman's correlation coefficients between observed and predicted EQ-5D-5L and SF-6D values. Models were validated using a 10-fold cross-validation method.

RESULTS

Considering the goodness of fit and predictive ability of models, the OLS Model 2 performed best for EQ-5D-5L (Adj R² = 58.09%, Pred R² = 58.93%, MAE = 0.0932, RMSE = 0.129) and the OLS Model 3 performed best for SF-6D (Adj R² = 54.90%, Pred R² = 55.62%, MAE = 0.0485, RMSE = 0.0634).

CONCLUSION

Our results demonstrated that algorithms developed based on OLS Models 1 and 2 are the best for predicted EQ-5D-5L and SF-6D values, respectively.

Characteristics and Survival of Korean Patients With Colorectal Cancer Based on Data From the Korea Central Cancer Registry Data

Purpose

The incidence of colorectal cancer (CRC) in Korea has increased remarkably during the past few decades. The present study investigated the characteristics and survival of patients with CRC in Korea as a function of time, tumor distribution, stage, sex, and age.

Methods

We retrieved clinical data on 326,712 CRC patients diagnosed between 1996 and 2015 from the Korea Central Cancer Registry. The incidence and the 5-year relative survival rates were compared across time period, tumor distribution, stage, sex, and age group.

Results

The percentage of patients with colon cancer increased from 49.5% in 1996–2000 to 66.4% in 2011–2015 while the percentage of patients with rectal cancer decreased from 50.5% to 33.6%. The 5-year relative survival rates for all CRCs improved from 58.7% in 1996–2000 to 75.0% in 2011–2015. For 1996–2000, survival rates were highest for patients with left-sided colon cancers, followed by those with right-sided, transverse, rectal, rectosigmoid cancers. For 2011–2015, the survival rates for patients with left-sided cancers were highest, followed by those with rectosigmoid, rectal, transverse, and right-sided colon cancers. Patients with local and regional, but not distant, SEER (Surveillance, Epidemiology, and End Results) stage tumors experienced significantly increased survival rates for 2006–2010 and 2011–2015. The proportion of CRC patients by age decreased in the order ≥70, 60–69, 50–59, 40–49, ≤39 years whereas survival rates decreased in the order 50–59, 60–69, 40–49, ≤39, ≥70 years.

Conclusion

Korean CRC has some distinct characteristics and survival patterns in terms of tumor distribution, stage, sex, and age. With time, survival outcomes have improved for both local and regional, but not distant, stage tumors.

A Randomized Phase 2 Trial of Consolidation Chemotherapy After Preoperative Chemoradiation Therapy Versus Chemoradiation Therapy Alone for Locally Advanced Rectal Cancer: KCSG CO 14-03

PURPOSE

Preoperative chemoradiation therapy (CRT) followed by total mesorectal excision (TME) in locally advanced rectal cancer is the standard of care. To date, the role of consolidation chemotherapy after CRT has rarely been addressed through randomized trials. This study aimed to evaluate the efficacy of CRT followed by consolidation chemotherapy compared with CRT alone.

METHODS AND MATERIALS

This study enrolled patients with adenocarcinoma of the rectum and cT3 or cT4 disease with any N category and no metastasis. In arm A (control arm), we planned CRT (50.4 Gy in 28 fractions) with capecitabine followed by TME. In arm B, 2 cycles of capecitabine and oxaliplatin were administered 1 week after the completion of CRT before TME (capecitabine, 1700 mg/m² per day from day 1 to 14, and oxaliplatin, 100 mg/m² on day 1, every 3 weeks). The downstaging rate (the proportion of ypT0 to ypT2 and ypN0M0) was the primary endpoint, which was to be tested with a 1-sided type I error of 15% and with 85% power.

RESULTS

From September 2014 to February 2016, 110 patients (56 in arm A and 54 in arm B) were randomized and 108 (55 in arm A and 53 in arm B) started CRT. TME was conducted per protocol in 96 patients (52 in arm A and 44 in arm B). In arms A and B, downstaging was achieved in 21.2% and 36.4% (P = .077), respectively, and the pathologic complete response rate was 5.8% and 13.6% (P = .167), respectively. Grade ≥3 adverse events occurred in 3.6% of patients in arm A and 9.4% of patients in arm B during the preoperative treatment phase and in 1.9% and 9.0%, respectively, during the postoperative recovery phase.

CONCLUSIONS

Consolidation chemotherapy with 2 cycles of capecitabine and oxaliplatin demonstrated a marginal improvement in the downstaging rate. However, a phase 3 trial of this strategy is discouraged because of the high dropout rate and safety issues.

Difference between right-sided and left-sided colorectal cancers: from embryology to molecular subtype

INTRODUCTION

Colorectal cancer is one of the most common malignancies in the world, and it exhibits differences in incidence, pathogenesis, molecular pathways, and outcome depending on the location of the tumor. Differences in the microbiome, clinical characteristics, and chromosomal and molecular characteristics have been reported between the right and left side of the colon. Areas covered: This review focuses on the latest developments in epidemiological and chromosomal and molecular studies, which have enhanced our understanding on the underlying genetic and immunological differences between the right-sided colon and the left-sided colorectum in metastatic colorectal cancer. Expert commentary: The numerous findings regarding differences between right- and left-sided colon cancers should have an impact on colorectal cancer screening and therapy. The location of the colorectal cancer should be considered before group stratification into genetic, clinical, and especially chemotherapy trials. A more tailored approach to colon cancer treatment would be highly desirable if future trials further support the hypothesis of two distinct tumor entities.

Comparison of oncological outcomes of right-sided colon cancer versus left-sided colon cancer after curative resection: Which side is better outcome?

PROPOSE

There are embryological origins, anatomical, histological, genetic, and immunological differences between right-sided colon cancer (RCC) and left-sided colon cancer (LCC). Many studies have sought to determine the survival and prognosis according to tumor location. This study aimed to analyze outcomes between RCC and LCC.

MATERIAL AND METHOD

Between January 2000 and December 2012, data on 414 patients who underwent curative resection for RCC and LCC were retrieved from a retrospective database. Propensity score matching (1:1) was performed and RCC was identified in 207 and LCC in 207 patients.

RESULTS

On average, RCC exhibited a more advanced N stage, increased tumor size, more frequently poorly differentiated tumors, more harvested lymph nodes, and more positivity of lymphovascular invasion than LCC. With a median follow-up of 66.7 months, the 5-year overall survival (OS) rates for RCC and LCC were 82.1% and 88.7%, respectively, (P < .05). The 5-year disease-free survival (DFS) rates were 81.4% (RCC) and 88.3% (LCC; P < .05). In stage III cancers, the DFS rates were 61.1% (RCC) and 81.9% (LCC; P < .05), while the OS rates were 65.6% (RCC) and 78.6% (LCC; P = .056).

CONCLUSION

On the basis of present data, LCC exhibited better survival outcomes than RCC after curative resection. Especially in stage III, LCC showed better oncologic outcomes. Proper specialized treatment related to the location of colon cancer is needed.

Survival rates and predictors of survival among colorectal cancer patients in a Malaysian tertiary hospital

Background

Colorectal cancer is the third most commonly diagnosed malignancy and the fourth leading cause of cancer-related death globally. It is the second most common cancer among both males and females in Malaysia. The economic burden of colorectal cancer is likely to increase over time owing to its current trend and aging population. Cancer survival analysis is an essential indicator for early detection and improvement in cancer treatment. However, there was a scarcity of studies concerning survival of colorectal cancer patients as well as its predictors. Therefore, we aimed to determine the 1-, 3- and 5-year survival rates, compare survival rates among ethnic groups and determine the predictors of survival among colorectal cancer patients.

Methods

This was an ambidirectional cohort study conducted at the University Malaya Medical Centre (UMMC) in Kuala Lumpur, Malaysia. All Malaysian citizens or permanent residents with histologically confirmed diagnosis of colorectal cancer seen at UMMC from 1 January 2001 to 31 December 2010 were included in the study. Demographic and clinical characteristics were extracted from the medical records. Patients were followed-up until death or censored at the end of the study (31st December 2010). Censored patients’ vital status (whether alive or dead) were cross checked with the National Registration Department. Survival analyses at 1-, 3- and 5-year intervals were performed using the Kaplan-Meier method. Log-rank test was used to compare the survival rates, while Cox proportional hazard regression analysis was carried out to determine the predictors of 5-year colorectal cancer survival.

Results

Among 1212 patients, the median survival for colorectal, colon and rectal cancers were 42.0, 42.0 and 41.0 months respectively; while the 1-, 3-, and 5-year relative survival rates ranged from 73.8 to 76.0%, 52.1 to 53.7% and 40.4 to 45.4% respectively. The Chinese patients had the lowest 5-year survival compared to Malay and Indian patients. Based on the 814 patients with data on their Duke’s staging, independent predictors of poor colorectal cancer (5-year) survival were male sex (Hazard Ratio [HR]: 1.41; 95% CI: 1.12, 1.76), Chinese ethnicity (HR: 1.41; 95% CI: 1.07,1.85), elevated (≥ 5.1 ng/ml) pre-operative carcino-embryonic antigen (CEA) level (HR: 2.13; 95% CI: 1.60, 2.83), Duke’s stage C (HR: 1.68; 95% CI: 1.28, 2.21), Duke’s stage D (HR: 4.61; 95% CI: 3.39, 6.28) and emergency surgery (HR: 1.52; 95% CI: 1.07, 2.15).

Conclusions

The survival rates of colorectal cancer among our patients were comparable with those of some Asian countries but lower than those found in more developed countries. Males and patients from the Chinese ethnic group had lower survival rates compared to their counterparts. More advanced staging and late presentation were important predictors of colorectal cancer survival. Health education programs targeting high risk groups and emphasizing the importance of screening and early diagnosis, as well as the recognition of symptoms and risk factors should be implemented. A nationwide colorectal cancer screening program should be designed and implemented to increase early detection and improve survival outcomes.

Correlation between microvascular characteristics and the expression of MVD, IGF-1 and STAT3 in the development of colonic polyps carcinogenesis

The aim of the present study was to investigate the correlation between vascular characteristics under narrow band imaging (NBI) and the expression of angiogenic factors of colorectal carcinoma and adenoma, and to evaluate the feasibility of NBI in vivo visualizing angiogenesis. Patients with colorectal polyps, which were pathologically confirmed as early carcinoma and adenoma, were recruited and examined by NBI. The vascular pattern was classified into type I (invisible or faintly visible vasculature), type II (clearly visible microvasculature that is regularly arranged in a round, oval honeycomb-like pattern) and type III (clearly visible microvasculature that is irregularly arranged in size and caliber or has irregular winding). Immunohistochemical staining was performed by cluster of differentiation (CD)34, insulin-like growth factor (IGF)-1 and signal transducer and activator of transcription 3 (STAT3). The histological results were compared with the vascular pattern under NBI. Overall, 64 sites (15 adenocarcinomas, 29 adenomas and 20 normal) from 58 patients were recruited in the study and examined by NBI. A higher proportion of adenomas (82.1%, 23/28) and adenocarcinomas (66.7%, 10/15) had vascular patterns II and III, respectively. The expression of microvessel density (MVD)-CD34 and IGF-1 in normal mucosa compared with adenomas and adenocarcinomas was significantly different (P<0.0001 and P=0.0062, respectively). MVD-CD34, IGF-1 and STAT3 expression in the sites displayed with vascular patterns I, II, and III was different significantly (P<0.0001, P=0.0010 and P=0.0055, respectively). The spearman correlation coefficient between NBI vascular pattern and MVD-CD34, IGF-1 and STAT3 expression was 0.67, 0.41 and 0.40, respectively. In conclusion, vascular-pattern analysis and the use of an NBI system may be a promising tool for evaluating angiogenesis of colorectal lesions in real-time endoscopy.