Data on the characteristics and the survival of korean patients with colorectal cancer from the Korea central cancer registry

Sex-specific differences in colorectal cancer: A multicenter retrospective cohort study

BACKGROUND

Due to sex-specific differences in the incidence and clinical and histopathological characteristics of colorectal cancer (CRC), understanding the impact of sex on CRC may suggest sex-targeted strategies for screening, treatment, and prevention, leading to improved prognosis of CRC. However, there have been few studies investigating the sex-specific differences in CRC in the Republic of Korea. We aimed to assess sex differences in CRC in the Republic of Korea.

METHODS

This was a retrospective, multicenter, cohort study of patients diagnosed with CRC between January 2012 and December 2013 at nine hospitals. Patients who had an uncertain CRC stage, were diagnosed with other cancers within 5 years, had carcinoma in situ, non-epithelial cancer, or primary cancer other than CRC, were excluded. Factors associated with overall survival or progression-free survival were investigated using Cox regression analysis. Cumulative probability of metachronous lesions was compared using the Kaplan-Meier estimator survival analysis and we compared the survival curves of each group using a log-rank test. Outcomes were compared using the chi-square, Fisher's exact, or Student's t-test, as appropriate.

RESULTS

Three thousand one hundred and forteen patients (1999 men, 1315 women) were included. There was no significant difference in the age at onset between men and women. The proportion of patients diagnosed through regular health check-ups, and asymptomatic at time of diagnosis, was higher in men (48.9% men vs. 42.0% women, p < .001). Rectal cancers were more common in men (38.8% men vs. 31.8% women, p < .001). Right colon cancers were more common in women (31.4% women vs. 22.7% men, p < .001). KRAS mutations were found in 109/317 (34.4%) women and 112/480 (23.3%) men. Overall CRC survival and progression-free survival were similar in both sexes.

CONCLUSION

Sex differences in CRC may be due to the biological and social-behavioral differences between the sexes. They should be considered during screening, diagnosis, and treatment of CRC for better outcomes.

Age-related differences in colon and rectal cancer survival by stage, histology, and tumour site: An analysis of United States SEER-18 data

Age-related differences in colon and rectal cancer survival have been observed, even after accounting for differences in background mortality. To determine how stage, tumour site, and histology contribute to these differences, we extracted age-specific one-year relative survival ratio (RS) stratified by these factors. We used colon and rectal cancer cases diagnosed between 2012 and 2016 from 18 United States Surveillance Epidemiology and End Results cancer registries. For colon cancer, 1-year RS ranged from 87.8 % [95 % Confidence Interval: 87.5-88.2] in the 50-64-year-olds to 62.3 % [61.3-63.3] in 85-99-year-olds and for rectal cancer ranged from 92.3 % [91.8-92.7] to 65.0 % [62.3-67.5]. With respect to stage, absolute differences in RS between 50-64-year-olds and 75-84-year-olds increased with increasing stage (from 6 [5-7] %-points in localised disease to 27 [25-29] %-points in distant disease) and were the highest for cancers of unknown stage (> 28 %-points). Age-related differences in survival were smallest for persons with tumours in the right-sided colon (8 [7-9] %-points) and largest for tumours of the colon without tumour site further specified (25 [21-29] %-points). With respect to histology, differences ranged from 7.4 % to 10.6 %-points for cancers with one of the three primary histologies (adenocarcinoma, mucinous adenocarcinoma, signet ring cell carcinoma) and were several-fold higher (42 %-points) for those with unknown/other histology (< 6 % of cases). Because age-related differences in survival were observed for all histologies and tumour sites, RS differences are unlikely to be driven by differences in the distribution of these factors by age. Differences in stage distribution by age are likely to contribute toward age-related differences in survival. Within stage groups, age differences in survival could be explained by frailty and/or therapy. Future studies incorporating data on treatment and geriatric conditions including frailty and comorbidity would support further understanding of the age gap in colon and rectal cancer survival.

Sex and gender perspectives in colorectal cancer

Historically women were frequently excluded from clinical trials and drug usage to protect unborn babies from potential harm. As a consequence, the impact of sex and gender on both tumour biology and clinical outcomes has been largely underestimated. Although interrelated and often used interchangeably, sex and gender are not equivalent concepts. Sex is a biological attribute that defines species according to their chromosomal makeup and reproductive organ, while gender refers to a chosen sexual identity. Sex dimorphisms are rarely taken into account, in either preclinical or clinical research, with inadequate analysis of differences in outcomes according to sex or gender still widespread, reflecting a gap in our knowledge for a large proportion of the target population. Underestimation of sex-based differences in study design and analyses has invariably led to 'one-drug' treatment regimens for both males and females. For patients with colorectal cancer (CRC), sex also has an impact on the disease incidence, clinicopathological features, therapeutic outcomes, and tolerability to anticancer treatments. Although the global incidence of CRC is higher in male subjects, the proportion of patients presenting right-sided tumours and BRAF mutations is higher among females. Concerning sex-related differences in treatment efficacy and toxicity, drug dosage does not take into account sex-specific differences in pharmacokinetics. Toxicity associated with fluoropyrimidines, targeted therapies, and immunotherapies has been reported to be more extensive for females with CRC than for males, although evidence about differences in efficacy is more controversial. This article aims to provide an overview of the research achieved so far into sex and gender differences in cancer and summarize the growing body of literature illustrating the sex and gender perspective in CRC and their impact in relation to tumour biology and treatment efficacy and toxicity. We propose endorsing research on how biological sex and gender influence CRC as an added value for precision oncology.

Metformin, Statin Use, and Female Colorectal Cancer: A Population-Based Cohort Study in Taiwan

In the last few years, the incidence of colorectal cancer (CRC) in women has gradually increased. However, epidemiological studies on the relationship between type II diabetes mellitus (T2DM) and female CRC and the effect of metformin or statins on female CRC are insufficient. To determine their association, we conducted a population-based cohort study on women in Taiwan. We collected data on a total of 396,521 women aged 40 to 64 years old from 1 January 2007 to 31 December 2009 from the National Health Insurance Research Database. We followed up on all participants in the cohort until the occurrence of CRC, the date for all death, or 31 December 2015. Full development of CRC was identified using the International Classification of Disease (ICD), 9th Revision, code 153. We estimated hazard ratios (HRs) and corresponding 95% confidence intervals (CIs) using the Cox proportional hazards model. Both metformin (adjusted hazard ratio, aHR = 1.12; 95% CI: 0.934–1.335, p = 0.227) and statin (aHR = 1.03; 95% CI: 0.906–1.172, p = 0.645) use showed no association with female CRC in a multivariate analysis. The findings indicate that metformin and statin use showed no protective effect against female colorectal cancer (CRC). An additional randomized trial is necessary to investigate the effect of metformin and statin use in CRC prevention.

Colorectal cancer chemotherapy: can sex-specific disparities impact on drug toxicities?

Purpose

Given the biological differences between females and males, sex-specific evaluations should be carried out to obtain better cancer prevention, diagnosis, and treatment strategies. To this purpose, our aim was to evaluate sex differences for toxicity in a cohort of colorectal cancer (CRC) patients undergoing chemotherapy.

Methods

We performed a retrospective study in 329 CRC patients. Differences between males and females were tested performing the Mann-Whitney U test or the Fisher exact test. Multivariate logistic regression models were computed to evaluate the association between sex and risk of chemotherapy agent-related toxicity.

Results

According association sex toxicity, significant differences were observed in the median number of episodes of nausea (p = 0.044), vomit (p = 0.007), heartburn (p = 0.022), thrombocytopenia (p = 0.005), mucositis (p = 0.024). Moreover, statistically significant differences between males and females were observed in the distribution of the highest toxicity grades of nausea (p = 0.024), heartburn (p = 0.016), and thrombocytopenia (p = 0.034). Females have an increased risk of vomit (p = 0.002), alopecia (p = 0.035), heartburn (p = 0.005), mucositis (p = 0.003), and lower risk for thrombocytopenia (p = 0.005).

Conclusion

According to the association of sex chemotherapy agent-related toxicities, females resulted on average at a significant increased risk of more common adverse events (constipation, dysgeusia, alopecia, heartburn, vomit, asthenia, nausea, pain events, and mucositis). Sex-tailored CRC chemotherapy treatment is necessary to obtain efficacy avoiding toxicity, based on patients’ biological and genetic characteristics, a vision that would change CRC setting, a stable disease but still orphan of a real tailored approach.

Supplementary information

The online version contains supplementary material available at 10.1007/s00228-022-03298-y.

Dynamics of changes in colorectal cancer incidence in the Podkarpackie region (Poland) in the years 1963-2014

Introduction

Colorectal cancer (CRC) in Podkarpackie in Poland is the third most common cancer in males (12.6% cancer diagnoses), and second among women (10.1% of recognised cancers).

Aim

An analysis of the trends in CRC incidence in the years 1963-2014 in Podkarpackie in the south-east of Poland.

Material and methods

A total of 19,460 CRC cases recorded in the period 1963–2014 in the National Cancer Registry as ICD C18-C21 cases were analysed.

Results

The overall cancer incidence rate in Podkarpackie Province was 20.4 in men and 16.8 in women per 100 thousand, and was lower than the Polish population by 12.4% for men and by 17.6% for women, respectively, in comparison to general Polish population rates. The mean age of CRC diagnosis grew from 64.0 years in males and 64.5 years in females in 1963–1969 to 67.6 and 68.4 years in 2010–2014, respectively.

Conclusions

In 1964–2014 the CRC incidence rate in the Podkarpackie region increased 12.7-fold in males and 8.1-fold in females. There was an observed stable growth of average annual increase in the CRC incidence rate in men in 1963–1999, but since 2000 a decline in this rate has been observed. In females there was a tendency towards increased average CRC incidence rate in Podkarpackie since 2000, while in the whole country the female population presented a stable decrease of this coefficient.

Clinicopathological patterns and survival outcomes of colorectal cancer among young adults in Malaysia: an institutional cohort study

INTRODUCTION

This study aimed to investigate the clinicopathological patterns and survival outcomes of young-onset colorectal cancer (CRC) in Malaysia.

METHODS

The study consisted of 206 patients with young-onset CRC (age < 50 years at diagnosis) and 1,921 patients with late-onset CRC (age ≥ 50 years at diagnosis) diagnosed during 2002-2016. The clinicopathological characteristics of patients with young-onset CRC were compared with those of patients with late-onset CRC during 2009-2013. Kaplan-Meier survival analysis was performed to determine the overall survival (OS) and disease-specific survival (DSS) in these patients.

RESULTS

The overall proportion of young-onset CRC was 10.7%. Mean age for young-onset CRC was 39.5 ± 7.4 years, with male-to-female ratio of 1.2:1.0. There were more Malay patients with young-onset CRC than late-onset CRC (44.0% vs. 19.9%, p = 0.004). Most CRC were diagnosed at advanced stage in both groups. However, young-onset CRC showed more aggressive tumour characteristics, such as poorer differentiation and mucinous subtype. Despite such differences, OS and DSS in both groups were similar (five-year OS for young-onset CRC vs. late-onset CRC: 44.2% vs. 49.0%, p = 0.40; five-year DSS for young-onset CRC vs. late-onset CRC: 48.8% vs. 57.6%, p = 0.53; mean survival of young-onset CRC vs. late-onset CRC: 4.9 years vs. 5.4 years, p = 0.15). Advanced stage at diagnosis and treatment modality were independent prognostic factors.

CONCLUSION

The unique ethnic and histological differences between patients with young- and late-onset CRC suggest that young-onset CRC may represent a distinct entity. However, despite such differences, prognosis between both groups were equivalent.

Patterns of age disparities in colon and lung cancer survival: a systematic narrative literature review

OBJECTIVES

To identify patterns of age disparities in cancer survival, using colon and lung cancer as exemplars.

DESIGN

Systematic review of the literature.

DATA SOURCES

We searched Embase, MEDLINE, Scopus and Web of Science through 18 December 2020.

ELIGIBILITY CRITERIA

We retained all original articles published in English including patients with colon or lung cancer. Eligible studies were required to be population-based, report survival across several age groups (of which at least one was over the age of 65) and at least one other characteristic (eg, sex, treatment).

DATA EXTRACTION AND SYNTHESIS

Two independent reviewers extracted data and assessed the quality of included studies against selected evaluation domains from the QUIPS tool, and items concerning statistical reporting. We evaluated age disparities using the absolute difference in survival or mortality rates between the middle-aged group and the oldest age group, or by describing survival curves.

RESULTS

Out of 3047 references, we retained 59 studies (20 for colon, 34 for lung and 5 for both sites). Regardless of the cancer site, the included studies were highly heterogeneous and often of poor quality. The magnitude of age disparities in survival varied greatly by sex, ethnicity, socioeconomic status, stage at diagnosis, cancer site, and morphology, the number of nodes examined and treatment strategy. Although results were inconsistent for most characteristics, we consistently observed greater age disparities for women with lung cancer compared with men. Also, age disparities increased with more advanced stages for colon cancer and decreased with more advanced stages for lung cancer.

CONCLUSIONS

Although age is one of the most important prognostic factors in cancer survival, age disparities in colon and lung cancer survival have so far been understudied in population-based research. Further studies are needed to better understand age disparities in colon and lung cancer survival.

PROSPERO REGISTRATION NUMBER

CRD42020151402.

Clinicopathological Characteristics and Outcome of Adolescent and Young Adult-Onset Microsatellite Stable Colorectal Cancer Patients

Purpose: Colorectal cancer (CRC) incidence is increasing in adults younger than 50 years. This study evaluated clinicopathological characteristics and outcome of adolescent and young adult (AYA)-onset sporadic CRC patients. Methods: Medical records of patients who were diagnosed adenocarcinoma of colon or rectum at Siriraj Hospital between 2007 and 2018 were retrospectively reviewed. The patients were classified into two groups: AYA-onset CRC (age 15-39 years) and adult-onset CRC (age >50 years). Associations between sporadic microsatellite stable (MSS) AYA-/adult-onset CRC and clinicopathological features and outcome were evaluated. Results: A total of 203 patients were diagnosed with AYA-onset CRC with no known history of familial CRC syndromes, 119 had data on mismatch repair status; 98 confirmed MSS CRC. AYA-onset CRC patients were commonly found with left-sided rather than right-sided tumors (77.1% vs. 22%) and late stage of disease (80.7% in stage III-IV vs. 19.3% in stage I-II). Compared with adult-onset CRC (218 patients), AYA-onset MSS CRC had more patients with female gender (p = 0.038), perineural invasion (p = 0.003), and signet ring cell/mucinous histology (p = 0.132). On univariate analysis, male gender and mucinous/signet ring cell histology had worse overall survival (OS) (p = 0.004 and p = 0.072, respectively) and remained significant in multivariate analysis for signet ring cell histology (p = 0.008). There was no difference in disease-free survival and OS between both age groups. Conclusions: Sporadic MSS AYA-onset CRC patients were associated with female gender and aggressive pathological characteristics. However, there was no difference in survival outcome between AYA-onset and adult-onset groups.

Cross-national analysis about the difference of histopathological management in Tis and T1 colorectal cancer between Japan and Korea

OBJECTIVES

There are differences in each country with regards to histopathological managements of colorectal cancer (CRC), such as definition of Tis and lymphatic and venous invasion. In this study, we compared Tis and T1 CRC in Japan and Korea.

METHODS

We retrospectively compared various clinical characteristics of consecutive patients who had Tis and T1 CRCs and who were newly diagnosed between 2010 and 2014 at the Kyoto Prefectural University of Medicine (Japan) and the Konkuk University (Korea).

RESULTS

Three hundred and sixty-five cases of T1 cancer and 510 cases of Tis cancer from 726 Japanese and 149 Korean patients were included. The rate of Tis in Japan was higher than in Korea (59.8% vs. 51.0%, P = 0.047), according to the difference of definition of Tis. In the analyses of 365 T1 CRCs, median age was higher in Japan than Korea (67.8 ± 10.6 vs. 62.2 ± 10.1, P < 0.001). Right-sided lesions were more frequent in Japan than they were in Korea (38.7% vs. 22.2%, P < 0.001). The rates of venous and lymphatic invasion were higher in Japan than they were in Korea (venous: 18.6% vs. 1.4%, P < 0.001, lymphatic: 25.3% vs. 13.7%, P = 0.042), according to the different methods of immunohistochemical examinations used (Japan: E-HE and D2-40, Korea: ERG).

CONCLUSIONS

Our study of T1 CRC showed that there were differences between Japan and Korea in tumor location, elderly incidence, and histopathological lymphatic and venous invasion. Additionally, rates of Tis were different between the two countries. In this international study for CRC, it is considered that we have to pay attention regarding the difference of histopathological definition and method in each country.

Epidemiology of colorectal cancer: incidence, mortality, survival, and risk factors

According to GLOBOCAN 2018 data, colorectal cancer (CRC) is the third most deadly and fourth most commonly diagnosed cancer in the world. Nearly 2 million new cases and about 1 million deaths are expected in 2018. CRC incidence has been steadily rising worldwide, especially in developing countries that are adopting the “western” way of life. Obesity, sedentary lifestyle, red meat consumption, alcohol, and tobacco are considered the driving factors behind the growth of CRC. However, recent advances in early detection screenings and treatment options have reduced CRC mortality in developed nations, even in the face of growing incidence. Genetic testing and better family history documentation can enable those with a hereditary predisposition for the neoplasm to take preventive measures. Meanwhile, the general population can reduce their risk by lowering their red meat, alcohol, and tobacco consumption and raising their consumption of fibre, wholesome foods, and certain vitamins and minerals.

Female Sex and Right-Sided Tumor Location Are Poor Prognostic Factors for Patients With Stage III Colon Cancer After a Curative Resection

Purpose

Stage-IIIC colon cancer is an advanced disease; however, its oncologic outcomes and prognostic factors remain unclear. In this study, we aimed to determine the predictors of disease-free survival (DFS) in patients with stage-IIIC colon cancer.

Methods

From a multicenter database, we retrospectively enrolled 611 patients (355 men and 256 women) who had undergone a potentially curative resection for a stage-IIIC colon adenocarcinoma between 2003 and 2011. The primary end-point was the 5-year DFS.

Results

The median age was 62 years; 213 and 398 patients had right-sided colon cancer (RCC) and left-sided colon cancer (LCC), respectively. The 5-year DFS in all patients was 52.0%; median follow-up time was 35 months (range, 1–134 months). A multivariate Cox regression revealed that female sex (hazard ratio [HR], 1.50; 95% confidence interval [CI], 1.19–1.90; P < 0.01), right-sided tumor location (HR, 1.65; 95% CI, 1.29–2.11; P < 0.01), lymphatic invasion (HR, 1.52; 95% CI, 1.08–2.15; P < 0.01) and a high (≥0.4) metastatic lymph node ratio (HR, 3.72; 95% CI, 2.63–5.24; P < 0.01) were independent predictors of worse 5-year DFS. Female patients with RCC were 1.79 fold more likely to experience recurrence than male patients with LCC.

Conclusion

Female sex and right-sided tumor location are associated with higher tumor recurrence rates in patients with stage-IIIC colon cancers. Aggressive treatment and close surveillance should be planned for patients in these groups.

Laparoscopic approach for left-sided T4 colon cancer is a safe and feasible procedure, compared to open surgery

BACKGROUND

A laparoscopic approach can be attempted for pathologic T4 (pT4) colon cancer. Our aim was to evaluate the clinico-oncologic outcomes following laparoscopic versus open surgery for right and left-sided pT4 colon cancer.

METHODS

From a multicentric collaborative database, we enrolled 245 patients with right-sided colon cancer (RCC, 128 laparoscopy and 117 open) and 338 with left-sided colon cancer (LCC, 176 laparoscopy and 162 open). All patients underwent intended curative surgery for histologically proven T4 adenocarcinoma, between 2004 and 2013. The primary end-point of our analysis was the oncologic outcome, including the 5-year disease-free survival (5 year-DFS) and the 5-year overall survival (5 year-OS). The secondary end-points included the R0 resection rate and postoperative complications.

RESULTS

Our study group included 224 T4N0 and 359 T4N+ tumors. The median follow-up was 53 months. For patients with RCC, the rate of postoperative morbidities was lower for the laparoscopy than that for the open surgery group (12.5 vs. 22.2%, p = 0.044). There was no difference in the R0 resection rate (94.5 vs. 96.6%, p = 0.425) between the groups. The 5 year-DFS and 5 year-OS rates were lower for the laparoscopy than that in the open group (48.9% vs. 59.2%, p = 0.093; 60.0% vs. 70.0%, p = 0.284, respectively), but this difference was not statistically significant. Among patients with LCC, there were no differences in the rate of postoperative complication and R0 resection (15.3 vs. 21.0%, p = 0.307; 96.0 vs. 95.7%, p = 0.875, respectively). Both groups had comparable 5 year-DFS and 5 year-OS rates (62.7% vs. 61.1%, p = 0.552; 72.0% vs. 71.8%, p = 0.611, respectively).

CONCLUSIONS

Laparoscopic surgery appears to be a safe procedure for patients with pT4 LCC, but requires careful consideration for patients with pT4 RCC.

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.

Early onset sporadic colorectal cancer: Worrisome trends and oncogenic features

Early onset colorectal cancers, defined as arising before 50 years of age, are a growing health hazard in western and eastern countries alike. The incidence of colon and rectal cancers in young individuals is projected to increase by as much as 90% and 140%, respectively, by 2030. Although several known cancer risk factors (e.g. smoking, alcohol, dietary habits) have been investigated, there is no single compelling explanation for this epidemiological trend. While some early onset colorectal cancers have been associated with germline mutations in cancer predisposition genes, genetic syndromes are implicated in only a fraction of these cancers (20%) and do not explain the rising incidence. Colorectal neoplasms develop through microsatellite instability or chromosomal instability pathways, with most of the early onset colorectal cancers exhibiting microsatellite stable phenotypes. Genome-wide hypomethylation is a feature of a subgroup of early onset cancers, which appears to be correlated with chromosomal instability and poor prognosis.

Updates on Cancer Epidemiology in Korea, 2018

Cancer is a major cause of morbidity and the most common cause of death in Korea. There are currently approximately 200,000 incident cancer cases and 78,000 individuals die from cancer every year. The factors directly related to cancer incidence, including aging, smoking, obesity, and Westernized dietary habits, have been increasing during the past several decades. Since 1999, trends toward increased incidence have been observed for thyroid, breast (in women), colorectal, and prostate cancer. Currently, these trends have changed direction, and the incidence of stomach and liver cancer in both sexes, and cervical cancer in women have continually declined. Although the number of cancer deaths increased by a factor of 2.7 from 1983 to 2016, the age-standardized mortality associated with cancer has been decreasing by 3% every year. The 5-year relative survival rate (RSR) has also improved over the past several decades, especially for stomach, prostate, and breast cancer, which had 5-year RSRs greater than 90% in the most recent report.

Socioeconomic and demographic inequalities in stage at diagnosis and survival among colorectal cancer patients: evidence from a Swiss population-based study

Socioeconomic inequalities in cancer stage at diagnosis and survival are important public health issues. This study investigates the association between socioeconomic position (SEP) and colorectal cancer (CRC) stage at diagnosis and survival in Switzerland, a European country with highest level of medical facilities and life expectancy. We used population-based CRC data from seven Swiss cantonal cancer registries 2001-2008 (N = 10,088) linked to the Swiss National Cohort (SNC). Follow-up information was available until the end of 2013. SEP was estimated based on education. The association between cancer stage and SEP was assessed using logistic regression models including cancer localization (colon/rectum), sex, age, civil status, urbanity of residence, language region, and nationality (Swiss/non-Swiss). Survival was analyzed using competing risk regressions reporting subhazard ratios (SHRs) for the risk of dying due to CRC. We observed a social gradient for later stage CRC with adjusted odds ratios (ORs) of 1.11 (95% CI: 0.97-1.19) and 1.28 (95% CI: 1.08-1.50) for middle and low SEP compared to high SEP. Further, single compared to married people had elevated odds of being diagnosed at later stages. Survival was lower in patients with CRC with low SEP in the unadjusted model (SHR: 1.18, 95% CI: 1.07-1.30). After adjustment for stage at diagnosis and further sociodemographic characteristics, significant survival inequalities by SEP disappeared but remained for non-Swiss compared to Swiss citizens and for patients living in nonurban areas compared to their urban counterparts. Swiss public health strategies should facilitate equal access to CRC screening and optimal CRC care for all social groups and in all regions of Switzerland.

Mitochondrial UQCRB as a new molecular prognostic biomarker of human colorectal cancer

Ubiquinol cytochrome c reductase binding protein (UQCRB) is important for mitochondrial complex III stability, electron transport, cellular oxygen sensing and angiogenesis. However, its potential as a prognostic marker in colorectal cancer (CRC) remains unclear. The aim of this study was to determine whether UQCRB can be used as a diagnostic molecular marker for CRC. The correlation between the expression of three genes (UQCRB, UQCRFS1 and MT-CYB) in the mitochondrial respiratory chain complex III and clinico-pathological features was determined. Compared to non-tumor tissues, UQCRB gene expression was upregulated in CRC tissues. Gene and protein expression of the genes were positively correlated. Copy number variation (CNV) differences in UQCRB were observed in CRC tissues (1.32-fold) compared to non-tumor tissues. The CNV of UQCRB in CRC tissues increased proportionally with gene expression and clinical stage. Single-nucleotide polymorphisms in the 3′-untranslated region of UQCRB (rs7836698 and rs10504961) were investigated, and the rs7836698 polymorphism was associated with CRC clinical stage. DNA methylation of the UQCRB promoter revealed that most CRC patients had high methylation levels (12/15 patients) in CRC tissues compared to non-tumor tissues. UQCRB overexpression and CNV gain were correlated with specific CRC clinico-pathological features, indicating clinical significance as a prognostic predictor in CRC. Gene structural factors may be more important than gene transcription repression factors with respect to DNA methylation in UQCRB overexpression. Our results provide novel insights into the critical role of UQCRB in regulating CRC, supporting UQCRB as a new candidate for the development of diagnostics for CRC patients.

Comparison of 627 patients with right- and left-sided colon cancer in China: Differences in clinicopathology, recurrence, and survival

Objective

Recent studies have reported increased mortality for right-sided colon cancers; however, the results are conflicting for different stage tumors. We examined the differences in clinicopathology between right- and left-sided colon cancers and the relationships between colon cancer location (right- and left-side) and 5-year disease-free survival (DFS) and overall survival (OS).

Methods

We identified patients from 2005 to 2008 with stage II/III colon cancer who underwent surgery for curative intent. We explored the impact of the tumor location on the postoperative DFS and OS using univariate and multivariate analyses.

Results

Of 627 patients, 50.6% (317/627) had right-sided colon cancer. These patients were more likely to have weight loss, second primary tumor, elevated preoperative carbohydrate antigen 19-9 (CA19-9), increased incidence of non-adenocarcinoma, more poorly differentiated tumors, vascular invasion, defective mismatch repair, and a lighter smoking history (P < 0.05). Right-sided colon cancer had a higher recurrence incidence compared with left-sided cancer (30.6% vs. 23.2%, P = 0.037), particularly with multiple metastatic sites in the first recurrence (17.5% vs. 5.6%, P = 0.020). Kaplan–Meier survival curves demonstrated a significant difference in the 5-year DFS rate between right- and left-sided cancers across all stages (68.1% vs. 75.2%, P = 0.043). However, there was no significant difference in the 5-year OS rate between the two groups (73.8% vs. 79.0%, P = 0.103). Subgroup analysis demonstrated that patients with left-sided colon cancer had a significantly better 5-year DFS and OS rates compared with those with right-sided disease at stage III (64.3% vs. 46.8%, P = 0.002; 69.5% vs. 53.5%, P = 0.006, respectively); there were no significant differences in the 5-year DFS and OS rates at stage II (85.2% vs. 85.9%, P = 0.819; 89.8% vs. 88.5%, P = 0.803, respectively). Adjusted Cox regression analysis showed no significant differences in the 5-year OS and DFS rates for stage II [hazard ratio (HR) = 1.203, 95% confidence interval (CI): 0.605–2.391, P = 0.598; HR = 0.980, 95% CI: 0.542–1.774, P = 0.948, respectively] or all stages combined (HR = 0.867, 95% CI: 0.613–1.227, P = 0.421; HR = 0.832, 95% CI: 0.606–1.142, P = 0.255, respectively). However, stage III left-sided cancer had higher 5-year OS and DFS rates (HR = 0.626, 95% CI: 0.414–0.948, P = 0.027; HR = 0.630, 95% CI: 0.428–0.926, P = 0.019, respectively).

Conclusion

We found that right- and left-sided colon cancers had significantly different clinicopathological characteristics. Right-sided colon cancer had a higher incidence of recurrence than left-sided disease. Patients with stage III right-sided colon cancer had a worse prognosis compared with those with stage III left-sided colon cancer.

Treatment of radiation-induced cystitis and vulvodynia via a ganglion impar block using a lateral approach under computed tomography guidance: a case report

Adjuvant radiation therapy (RT) after colorectal cancer surgery can prevent local recurrence, but has several side effects. Precise injection of drugs into the affected areas is complicated by radiation-induced fibrosis of soft or connective tissue. A 48-year-old woman experienced severe intractable perineal pain, dysuria, urinary urgency, and frequent urination after rectal cancer surgery and adjuvant RT, and was diagnosed with radiation-induced cystitis and vulvodynia. Her symptoms persisted despite two fluoroscopy-guided ganglion impar blocks. Fluoroscopy revealed atypical needle tip positioning and radiolucent dye distribution, presumably due to radiation-induced fibrosis in the target region. We performed two computed tomography (CT)-guided ganglion impar blocks by using a lateral approach, which allowed more accurate po-sitioning of the needle tip. Her pain visual analog score decreased from 9 to 3, and she recently resumed sexual intimacy. CT guidance is a viable alternative to fluoroscopy guidance when performing ganglion impar blocks in fibrotic areas.

Characteristics and outcomes of endoscopically resected colorectal cancers that arose from sessile serrated adenomas and traditional serrated adenomas

Background/Aims

The efficacy and safety of endoscopic resection of colorectal cancer derived from sessile serrated adenomas or traditional serrated adenomas are still unknown. The aims of this study were to verify the characteristics and outcomes of endoscopically resected early colorectal cancers developed from serrated polyps.

Methods

Among patients who received endoscopic resection of early colorectal cancers from 2008 to 2011, cancers with documented pre-existing lesions were included. They were classified as adenoma, sessile serrated adenoma, or traditional serrated adenoma according to the baseline lesions. Clinical characteristics, pathologic diagnosis, and outcomes were reviewed.

Results

Overall, 208 colorectal cancers detected from 198 patients were included: 198 with adenoma, five with sessile serrated adenoma, and five with traditional serrated adenoma. The sessile serrated adenoma group had a higher prevalence of high-grade dysplasia (40.0% vs. 25.8%, P<0.001) than the adenoma group. During follow-up, local recurrence did not occur after endoscopic resection of early colorectal cancers developed from serrated polyps. In contrast, two cases of metachronous recurrence were detected within a short follow-up period.

Conclusions

Cautious observation and early endoscopic resection are recommended when colorectal cancer from serrated polyp is suspected. Colorectal cancers from serrated polyp can be treated successfully with endoscopy.

Colorectal cancer in the young, many questions, few answers

At a time where the incidence of colorectal cancer, a disease predominantly of developed nations, is showing a decline in those 50 years of age and older, data from the West is showing a rising incidence of this cancer in young individuals. Central to this has been the 75% increase in rectal cancer incidence in the last four decades. Furthermore, predictive data based on mathematical modelling indicates a 124 percent rise in the incidence of rectal cancer by the year 2030 - a statistic that calls for collective global thought and action. While predominance of colorectal cancer (CRC) is likely to be in that part of the large bowel distal to the splenic flexure, which makes flexible sigmoidoscopic examination an ideal screening tool, the cost and benefit of mass screening in young people remain unknown. In countries where the incidence of young CRC is as high as 35% to 50%, the available data do not seem to indicate that the disease in young people is one of high red meat consuming nations only. Improvement in our understanding of genetic pathways in the aetiology of CRC, chiefly of the MSI, CIN and CIMP pathway, supports the notion that up to 30% of CRC is genetic, and may reflect a familial trait or environmentally induced changes. However, a number of other germline and somatic mutations, some of which remain unidentified, may play a role in the genesis of this cancer and stand in the way of a clear understanding of CRC in the young. Clinically, a proportion of young persons with CRC die early after curative surgery, presumably from aggressive tumour biology, compared with the majority in whom survival after operation will remain unchanged for five years or greater. The challenge in the future will be to determine, by genetic fingerprinting or otherwise, those at risk of developing CRC and the determinants of survival in those who develop CRC. Ultimately, prevention and early detection, just like for those over 50 years with CRC, will determine the outcome of CRC in young persons. At present, aside from those with an established familial tendency, there is no consensus on screening young persons who may be at risk. However, increasing awareness of this cancer in the young and the established benefit of prevention in older persons, must be a message that should be communicated with medical students, primary health care personnel and first contact doctors. The latter constitutes a formidable challenge.

Validation of a quantitative 12-multigene expression assay (Oncotype DX(®) Colon Cancer Assay) in Korean patients with stage II colon cancer: implication of ethnic differences contributing to differences in gene expression

Purpose

To evaluate the Recurrence Score^® of the quantitative 12-multigene expression assay and to determine risk groups based on the continuous Recurrence Score^® in Korean patients.

Method

A total of 95 patients with pathological T3N0 tumors and mismatch repair-proficient tumors were enrolled. The Recurrence Score^® was used to classify risk groups (low risk, <30; intermediate risk, 30–40; high risk, ≥41).

Results

Fifty-four patients (56.8%) were aged over 70 years. There were 49 men (51.6%) and 56 cases of right-sided colon cancer (58.9%). Eight cases (8.4%) had well-differentiated tumors, and 86 cases (90.5%) showed moderate differentiation. Only one case (1.1%) had a poorly differentiated tumor. Three patients (3.2%) had lymphovascular invasion. Sixty-one patients were identified as low risk (64.2%) and 34 patients as intermediate risk (35.8%). There were no high-risk patients. Although not significant, the 3-year recurrence risk increased with the Recurrence Score^®.

Conclusion

Distribution patterns of risk groups based on the Recurrence Score^®, particularly the absence of a high-risk group, were different from the prior validation studies. These findings suggest that ethnic differences between Koreans and Western patients are potential contributing factors for different gene expressions in the quantitative 12-multigene expression assay.

Clinical Features and Prognosis of Resectable Primary Colorectal Signet-Ring Cell Carcinoma

BACKGROUND/AIMS

We attempted to investigate the prognosis of signet-ring cell carcinoma (SRC) patients who underwent curative surgery by comparing them with age-, sex-, and stage-matched non-mucinous adenocarcinoma (NMAC) patients.

METHODS

Between January 2003 and December 2011, 19 patients with primary SRC of the colorectum underwent curative surgery. Four SRC patients under the age of 40 were excluded, and the clinicopathological data of 15 patients (7 men; median age, 56 years) were reviewed and compared with the data of 75 NMAC patients matched by age, sex, and pathologic stage.

RESULTS

The median follow-up duration was 30.1 months for the SRC group and 43.7 months for the NMAC group (P=0.141). Involvement of the left side of the colon (73.3% vs. 26.7%, P=0.003) and infiltrative lesions such as Borrmann types 3 and 4 (85.7% vs. 24.0%, P=0.001) were more common in the SRC group than in the NMAC group. The five-year overall survival rate was significantly lower for patients with SRC than for those with NMAC (46.0% vs. 88.7%, hazard ratio, 6.99; 95% confidence interval, 2.33-20.95, P=0.001).

CONCLUSIONS

Patients with even resectable primary colorectal SRC had a poorer prognosis than age-, sex-, and stage-matched colorectal NMAC patients.

Temporal Epidemiological Assessment of Colorectal Cancer Incidence and Mortality in East Kazakhstan, 2004-2013

Colorectal cancer incidence and mortality in Kazakhstan are relatively high but exact statistics have hitherto been lacking and trends over time are unclear. The present study was therefore undertaken to retrospectively assess data for East Kazakhstan, accessed from the central registration office, for the period 2004-2013. Approximate age standardized data for incidence and mortality were generated and compared across age groups, gender and year. It was determined that during the studied period 3,417 new cases of colorectal cancer were registered and 2,259 died of this pathology. Average cancer cancer incidence and mortality over the ten years were 24.1/105 and 15.9/105 respectively, and the overall ratio of mortality/incidence (M/I) was 0.69:1 (range 0.58-0.73). Both incidence and mortality tended to remain constant in both males and females. The male to female ratios also did not significantly vary over time but a trend for improvement of the mortality to incidence ratio was observed, especially for rectum. Whether this might be related to screening remains unclear. These preliminary data indicate that whereas colorectal cancer continues to be important, change in environmental factors are not having a great impact on incidence in East Kazakhstan.

Efficacy and Safety of Low-Dose-Rate Endorectal Brachytherapy as a Boost to Neoadjuvant Chemoradiation in the Treatment of Locally Advanced Distal Rectal Cancer: A Phase-II Clinical Trial

PURPOSE

Despite advances in rectal cancer treatment over the last decade, local control and risk of late side effects due to external beam radiation therapy (EBRT) remain as concerns. The present study aimed to investigate the efficacy and the safety of low-dose-rate endorectal brachytherapy (LDRBT) as a boost to neoadjuvant chemoradiation for use in treating locally advanced distal rectal adenocarcinomas.

METHODS

This phase-II clinical trial included 34 patients (as the study arm) with newly diagnosed, locally advanced (clinical T3-T4 and/or N1/N2, M0) lower rectal cancer. For comparative analysis, 102 matched patients (as the historical control arm) with rectal cancer were also selected. All the patients were treated with LDRBT (15 Gy in 3 fractions) and concurrent chemoradiation (45-50.4 Gy). Concurrent chemotherapy consisted of oxaliplatin 130 mg/m(2) intravenously on day 1 plus oral capecitabine 825 mg/m(2) twice daily during LDRBT and EBRT.

RESULTS

The study results revealed a significant differences between the study arm and the control arm in terms in the pathologic tumor size (2.1 cm vs. 3.6 cm, P = 0.001), the pathologic tumor stage (35% T3-4 vs. 65% T3-4, P = 0.003), and the pathologic complete response (29.4% vs. 11.7%, P < 0.028). Moreover, a significantly higher dose of EBRT (P = 0.041) was found in the control arm, and a longer time to surgery was observed in the study arm (P < 0.001). The higher rate of treatment-related toxicities, such as mild proctitis and anemia, in the study arm was tolerable and easily manageable.

CONCLUSION

A boost of LDRBT can optimize the pathologic complete response, with acceptable toxicities, in patients with distal rectal cancer.

Complete resection of colorectal adenomas: what are the important factors in fellow training?

BACKGROUND

The complete removal of adenomatous polyps is important for reducing interval cancer after colonoscopy.

AIMS

To identify factors affecting the completeness of colonoscopic polypectomies and to evaluate the experience level of fellows who achieve competence compared with that of experts.

METHODS

Medical records of 1,860 patients who underwent at least one polypectomy for an adenomatous polyp at Seoul National University Hospital between March 2011 and February 2013 were retrospectively reviewed. A total of 3,469 adenomatous polyps were included. The lateral and deep margins of the resected polyps were evaluated to check the resection completeness.

RESULTS

Of the 3,469 adenomatous polyps, 1,389 (40.0 %) were removed by two experts and 2,080 (60.0 %) were removed by seven fellows. In the expert-treated group, larger size [odds ratio (OR) 2.81 for ≥20 mm, 95 % confidence interval (CI) 1.64-4.84, P < 0.001] and right-sided location (OR 1.31, 95 % CI 1.05-1.63, P = 0.019) were associated with incomplete resection. In the fellow-treated group, not only polyp characteristics [right-sided location (OR 1.41, 95 % CI 1.18-1.69, P < 0.001)], but also the cumulative number of procedures was also related to resection completeness. After 300 polypectomies, the complete resection rate of the fellows was comparable to that of the experts.

CONCLUSIONS

In the fellow-treated group, the level of procedure experience was closely associated with the polypectomy outcomes. Meticulous attention is critical to ensure the completeness of polypectomies performed by trainee endoscopists during the training program.

Sex- and gender-specific disparities in colorectal cancer risk

Colorectal cancer is one of the most common causes of cancer morbidity both in men and in women. However, females over 65 years old show higher mortality and lower 5-year survival rate of colorectal cancer compared to their age-matched male counterparts. The objective of this review is to suggest gender-based innovations to improve colorectal cancer outcomes in females. Women have a higher risk of developing right-sided (proximal) colon cancer than men, which is associated with more aggressive form of neoplasia compared to left-sided (distal) colon cancer. Despite differences in tumor location between women and men, most of scientific researchers do not consider sex specificity for study design and interpretation. Also, colorectal cancer screening guidelines do not distinguish females from male, which may explain the higher frequency of more advanced neoplasia when tumors are first detected and false negative results in colonoscopy in females. Moreover, socio-cultural barriers within females are present to delay screening and diagnosis. Few studies, among studies that included both men and women, have reported sex-specific estimates of dietary risk factors which are crucial to establish cancer prevention guidelines despite sex- and gender-associated differences in nutrient metabolism and dietary practices. Furthermore, anti-cancer drug use for colorectal cancer treatment can cause toxicity to the reproductive system, and gender-specific recurrence and survival rates are reported. Therefore, by understanding sex- and gender-related biological and socio-cultural differences in colorectal cancer risk, gender-specific strategies for screening, treatment and prevention protocols can be established to reduce the mortality and improve the quality of life.

Sex- and gender-specific disparities in colorectal cancer risk

Colorectal cancer is one of the most common causes of cancer morbidity both in men and in women. However, females over 65 years old show higher mortality and lower 5-year survival rate of colorectal cancer compared to their age-matched male counterparts. The objective of this review is to suggest gender-based innovations to improve colorectal cancer outcomes in females. Women have a higher risk of developing right-sided (proximal) colon cancer than men, which is associated with more aggressive form of neoplasia compared to left-sided (distal) colon cancer. Despite differences in tumor location between women and men, most of scientific researchers do not consider sex specificity for study design and interpretation. Also, colorectal cancer screening guidelines do not distinguish females from male, which may explain the higher frequency of more advanced neoplasia when tumors are first detected and false negative results in colonoscopy in females. Moreover, socio-cultural barriers within females are present to delay screening and diagnosis. Few studies, among studies that included both men and women, have reported sex-specific estimates of dietary risk factors which are crucial to establish cancer prevention guidelines despite sex- and gender-associated differences in nutrient metabolism and dietary practices. Furthermore, anti-cancer drug use for colorectal cancer treatment can cause toxicity to the reproductive system, and gender-specific recurrence and survival rates are reported. Therefore, by understanding sex- and gender-related biological and socio-cultural differences in colorectal cancer risk, gender-specific strategies for screening, treatment and prevention protocols can be established to reduce the mortality and improve the quality of life.

Surgical outcomes of Korean ulcerative colitis patients with and without colitis-associated cancer

AIM: To determine the clinicopathologic characteristics of surgically treated ulcerative colitis (UC) patients, and to compare the characteristics of UC patients with colitis-associated cancer (CAC) to those without CAC.

METHODS: Clinical data on UC patients who underwent abdominal surgery from 1980 to 2013 were collected from 11 medical institutions. Data were analyzed to compare the clinical features of patients with CAC and those of patients without CAC.

RESULTS: Among 415 UC patients, 383 (92.2%) underwent total proctocolectomy, and of these, 342 (89%) were subjected to ileal pouch-anal anastomosis. CAC was found in 47 patients (11.3%). Adenocarcinoma was found in 45 patients, and the others had either neuroendocrine carcinoma or lymphoma. Comparing the UC patients with and without CAC, the UC patients with CAC were characteristically older at the time of diagnosis, had longer disease duration, underwent frequent laparoscopic surgery, and were infrequently given preoperative steroid therapy (P < 0.001-0.035). During the 37 mo mean follow-up period, the 3-year overall survival rate was 82.2%.

CONCLUSION: Most Korean UC patients experience early disease exacerbation or complications. Approximately 10% of UC patients had CAC, and UC patients with CAC had a later diagnosis, a longer disease duration, and less steroid treatment than UC patients without CAC.

Incidence of venous thromboembolism following major surgery in Korea: from the Health Insurance Review and Assessment Service database

BACKGROUND

Data on the incidence of venous thromboembolism (VTE) following major surgery in Asian populations are limited.

METHODS

Using the Korean Health Insurance Review and Assessment Service database, we performed a nationwide population-based epidemiologic study to estimate the incidence of VTE after major orthopedic, cancer, and benign surgeries. VTE cases were identified from all patients undergoing major surgery between 2007 and 2011 using both diagnostic and drug codes as treatment evidence of VTE within 5 weeks of surgery. We also calculated the relative risk of VTE in major orthopedic and cancer surgery compared to benign surgery.

RESULTS

The overall rates of postoperative VTE were 1.24%, 0.67%, and 0.05% for major orthopedic, cancer, and benign surgeries, respectively. Hip fracture (1.60%) and colorectal cancer surgeries (1.67%) were associated with the highest rates of VTE, and the rates steadily increased during the study period. Advanced age, female sex, and general anesthesia were independent risk factors for VTE. Patients undergoing surgery for colorectal, pancreatic, ovarian, and esophageal cancer, and major orthopedic surgery had a > 20-fold higher risk of VTE than those undergoing benign surgery.

CONCLUSIONS

This is the largest epidemiologic study to investigate the incidence of VTE after major surgery in Asia, demonstrating that the rates of postoperative VTE are lower than in Caucasian populations. This study contributes to a better understanding of the differences in postoperative VTE development between Korean and Caucasian populations; the data also suggest that perioperative prophylactic strategies in Asians should be based on studies of such populations.

Colonoscopy Quality is the Answer for the Emerging Issue of Interval Cancer

Colonoscopy is currently regarded as the gold standard and preferred screening method for colorectal cancer (CRC). Recently, however, a limitation of colonoscopy in the prevention of CRCs has been identified, particularly in the right-sided colon, and the problem of so-called interval cancers has emerged. The prevalence of interval cancer is estimated to be between 4% and 8% of CRCs detected. Although the exact etiology of interval cancer remains unknown, factors implicated in the development of interval cancers include missed lesions at the time of colonoscopy, incomplete resection of previous neoplastic lesions, different tumor biology, and serrated pathway of carcinogenesis. However, recent evidence suggests that interval cancers are related to the training of the endoscopist and quality of the colonoscopy rather than tumor biology. Therefore, the importance of adequate training and continuous monitoring of the colonoscopy quality, which are amenable to improvement, cannot be overstated in order to prevent the risk of interval cancers. In this study, the current literature regarding the prevalence and potential factors related to interval cancers and colonoscopy quality-related issues are reviewed.