Incidence trends and age distribution of colorectal cancer by subsite in Guangzhou, 2000-2011

Statistical methods for measuring trends in colorectal cancer incidence in registries: A systematic review

Background

Monitoring cancer trends in a population is essential for tracking the disease’s burden, allocating resources, and informing public health policies. This review describes variations in commonly employed methods to estimate colorectal cancer (CRC) incidence trends.

Methods

We performed a systematic literature search in four databases to identify population-based studies reporting CRC incidence trends, published between January 2010 and May 2020. We extracted and described data on methods to estimate trends and assess model validity, and the software used.

Results

This review included 145 articles based on studies conducted in five continents. The majority (93%) presented visual summaries of trends combined with absolute, relative, or annual change estimates. Fourteen (10%) articles exclusively calculated the relative change in incidence over a given time interval, presented as the percentage of change in rates. Joinpoint regression analysis was the most commonly used method for assessing incidence trends (n= 65, 45%), providing estimates of the annual percentage change (APC) in rates. Nineteen (13%) studies performed Poisson regression and 18 (12%) linear regression analysis. Age-period-cohort modeling- a type of generalized linear models- was conducted in 18 (12%) studies. Thirty-nine (37%) of the studies modeling incidence trends (n=104, 72%) indicated the method used to evaluate model fitness. The joinpoint program (52%) was the statistical software most commonly used.

Conclusion

This review identified variation in the calculation of CRC incidence trends and inadequate reporting of model fit statistics. Our findings highlight the need for increasing clarity and transparency in reporting methods to facilitate interpretation, reproduction, and comparison with findings from previous studies.

Predicting Surgical Benefit for Primary Tumor Resection in Patients with Stage IV Colorectal Cancer.. [DOI: 10.21203/rs.3.rs-2031087/v1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0]

Purpose There exists continuous controversy regarding the effect of primary tumor resection (PTR) for stage IV colorectal cancer (CRC) patients. Little is known about how to predict the patients’ survival benefit from PTR. This study aimed to develop a tool for surgical benefit prediction. Methods Stage IV CRC patients diagnosed between 2010 and 2015 from the Surveillance, Epidemiology, and End Results database were included. After propensity score matching, patients receiving PTR that survived longer than the median cancer-specific survival (CSS) time of those who did not undergo PTR were considered to benefit from surgery. Logistic regression analysis identified prognostic factors influencing the surgical benefit, based on which a nomogram was constructed. A user-friendly webserver was then built for convenient clinical use. The predictive model was assessed using Harrell’s concordance index, calibration plot, receiver operative curve and decision curve analysis. Results The median CSS of the PTR group was 23 months, which was significantly longer than the non-PTR group (12 months, P < 0.001). In the PTR group, 32.9% of patients did not benefit from surgery. Logistic regression analysis identified age, tumor location, CEA level, histological grade, number of distant metastasis, and preoperative chemotherapy independently associated with surgical benefit. The established prognostic nomogram demonstrated satisfactory performance. Conclusion PTR was associated with prolonged survival in stage IV CRC. The proposed nomogram could be used as a risk-to-benefit assessment evidenced-based platform for selecting appropriate patients to undergo PTR.

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

OBJECTIVE

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

DESIGN

11-year retrospective cross-sectional study.

SETTING

A national referral hospital in Jakarta, Indonesia.

PARTICIPANTS

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

METHODS

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

MAIN OUTCOMES

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

RESULTS

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

CONCLUSIONS

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

A systematic review of methods to estimate colorectal cancer incidence using population-based cancer registries

Background

Epidemiological studies of incidence play an essential role in quantifying disease burden, resource planning, and informing public health policies. A variety of measures for estimating cancer incidence have been used. Appropriate reporting of incidence calculations is essential to enable clear interpretation. This review uses colorectal cancer (CRC) as an exemplar to summarize and describe variation in commonly employed incidence measures and evaluate the quality of reporting incidence methods.

Methods

We searched four databases for CRC incidence studies published between January 2010 and May 2020. Two independent reviewers screened all titles and abstracts. Eligible studies were population-based cancer registry studies evaluating CRC incidence. We extracted data on study characteristics and author-defined criteria for assessing the quality of reporting incidence. We used descriptive statistics to summarize the information.

Results

This review retrieved 165 relevant articles. The age-standardized incidence rate (ASR) (80%) was the most commonly reported incidence measure, and the 2000 U.S. standard population the most commonly used reference population (39%). Slightly more than half (54%) of the studies reported CRC incidence stratified by anatomical site. The quality of reporting incidence methods was suboptimal. Of all included studies: 45 (27%) failed to report the classification system used to define CRC; 63 (38%) did not report CRC codes; and only 20 (12%) documented excluding certain CRC cases from the numerator. Concerning the denominator estimation: 61% of studies failed to state the source of population data; 24 (15%) indicated census years; 10 (6%) reported the method used to estimate yearly population counts; and only 5 (3%) explicitly explained the population size estimation procedure to calculate the overall average incidence rate. Thirty-three (20%) studies reported the confidence interval for incidence, and only 7 (4%) documented methods for dealing with missing data.

Conclusion

This review identified variations in incidence calculation and inadequate reporting of methods. We outlined recommendations to optimize incidence estimation and reporting practices. There is a need to establish clear guidelines for incidence reporting to facilitate assessment of the validity and interpretation of reported incidence.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12874-022-01632-7.

Colorectal Cancer Incidence and Mortality Trends and Analysis of Risk Factors in China from 2005 to 2015

Purpose

This study aimed to analyze incidence and mortality trends and risk factors of colorectal cancer (CRC) in China during 2005–2015.

Materials and Methods

Patient cases were extracted from the Chinese Cancer Registry Annual Report. Joinpoint regression and Poisson regression were applied to analyze incidence and mortality trends and risk factors of CRC. Age-period-cohort model was used to evaluate the age, period and cohort effects on CRC.

Results

The standardized incidence and mortality rate of CRC in China showed a decreasing trend during 2005–2015. The incidence in men (APC=−1.22%, P<0.05) decreased from 2005 to 2015 and decreased in women (APC =−3.55%, P<0.05) from 2005 to 2013, then increased during 2013–2015 (APC =18.77%, P<0.05). The incidence and mortality in urban areas were higher than those in rural (The incidence in urban: APC =−0.97%, P<0.05; rural: APC =1.94%, P<0.05; the mortality in urban: APC =−0.67%, P<0.05; rural: APC =0.29%). For age-specific rates, the incidence begins to increase significantly at 40–45 age group and reached a peak at 75; the mortality increased significantly at 45–50. The age effect increased with age in general. The 1920 birth cohort had the highest risk of colorectal cancer incidence and death. Poisson regression showed region, gender and age were independent risk factors of CRC.

Conclusion

The age-adjusted standardized incidence rate (ASIR) and age-adjusted standardized mortality rate (ASMR) of CRC in China during 2005–2015 were decreasing. A great concern on men, rural areas and people aged over 75 should be aroused to prevent colorectal cancer.

Different factors are associated with conventional adenoma and serrated colorectal neoplasia

Current data shows there are differences in factors associated with colorectal neoplasia based on geographical location and cultural settings. There are no studies focusing on the association between environmental factors and colorectal polyps in Australia. The aim of this study was to prospectively evaluate the association of various factors with different colorectal neoplasia histology. We utilized a simplified one-page questionnaire for patients undergoing colonoscopy for information on age; gender; comorbidities; family history of colorectal cancer; physical activity; smoking; diet; alcohol intake; and body mass index. Factors were then evaluated for association with the presence of: (1) neoplastic lesions; (2) conventional adenomas; (3) neoplastic serrated polyps; (4) any lesions (past and present); and (5) hyperplastic polyps. 291 procedures and 260 patients were included. Factors with a p-value < 0.2 in a univariate regression were included in an initial multivariable regression model. Backwards elimination was then performed, removing one predictor at a time until only significant predictors remained. In the final multivariable model, age≥65, male gender, type-2 diabetes mellitus, active smoking and family history of colorectal cancer were found to be statistically significant predictors for the presence of colorectal neoplasia. However, the significant predictors found for conventional adenomas (older age, male gender and smoking) were different from the significant predictors for neoplastic serrated polyps (type-2 diabetes mellitus and family history of colorectal cancer). Older age, male gender, type-2 diabetes mellitus, and smoking were significantly associated with the presence of colorectal neoplasia. The factors associated with conventional adenomas differed from those associated with neoplastic serrated polyps.

Elevating H3K27me3 level sensitizes colorectal cancer to oxaliplatin

Histone methylation is a context-dependent modification that regulates gene expression, and the trimethylation of histone H3 lysine 27 (H3K27me3) usually induces gene silencing. Overcoming colorectal cancer (CRC) chemoresistance is currently a huge challenge, but the relationship between H3K27me3 modification and chemoresistance remains largely unclear. Here, we found that H3K27me3 levels positively correlated with the metastasis-free survival of CRC patients and a low H3K27me3 level predicted a poor outcome upon chemotherapeutic drug treatment. Oxaliplatin stimulation significantly induced the expression of H3K27 lysine demethylase 6A/6B (KDM6A/6B), thus decreasing the level of H3K27me3 in CRC cells. Elevation of H3K27me3 level through KDM6A/6B depletion or GSK-J4 (a KDM6A/6B inhibitor) treatment significantly enhanced oxaliplatin-induced apoptosis. Conversely, when inhibiting the expression of H3K27me3 by EPZ-6438, an inhibitor of the histone methyltransferase EZH2, the proportion of apoptotic cells remarkably decreased. In addition, the combination of GSK-J4 and oxaliplatin significantly inhibited tumor growth in an oxaliplatin-resistant patient-derived xenograft model. Importantly, we revealed that oxaliplatin treatment dramatically induced NOTCH2 expression, which was caused by downregulation of H3K27me3 level on the NOTCH2 transcription initiation site. Thus, the activated NOTCH signaling promoted the expression of stemness-related genes, which resulted in oxaliplatin resistance. Furthermore, oxaliplatin-induced NOTCH signaling could be interrupted by GSK-J4 treatment. Collectively, our findings suggest that elevating H3K27me3 level can improve drug sensitivity in CRC patients.

Trends in the epidemiology of young-onset colorectal cancer: a worldwide systematic review

BACKGROUND

Recent data suggest that the risk of young-onset colorectal cancer (yCRC), in adults less than 50 years of age, is increasing. To confirm findings and identify contemporary trends worldwide, we conducted a systematic review of studies examining population-level trends in yCRC epidemiology.

METHODS

We searched MEDLINE (1946-2018), EMBASE (1974-2018), CINAHL (1982-2018), and Cochrane Database of Systematic Reviews (2005-2018) for studies that used an epidemiologic design, assessed trends in yCRC incidence or prevalence, and published in English. Extracted information included country, age cut-off for yCRC, and reported trends in incidence or prevalence (e.g. annual percent change [APC]). We pooled similarly reported trend estimates using random effects models.

RESULTS

Our search yielded 8695 articles and after applying our inclusion criteria, we identified 40 studies from 12 countries across five continents. One study assessed yCRC prevalence trends reporting an APCp of + 2.6 and + 1.8 among 20-39 and 40-49 year olds, respectively. 39 studies assessed trends in yCRC incidence but with substantial variability in reporting. Meta-analysis of the most commonly reported trend estimate yielded a pooled overall APCi of + 1.33 (95% CI, 0.97 to 1.68; p < 0.0001) that is largely driven by findings from North America and Australia. Also contributing to these trends is the increasing risk of rectal cancer as among 14 studies assessing cancer site, nine showed an increased risk of rectal cancer in adults less than 50 years with APCi up to + 4.03 (p < 0.001).

CONCLUSIONS

Our systematic review highlights increasing yCRC risk in North America and Australia driven by rising rectal cancers in younger adults over the past two decades.

Modulation of Redox Homeostasis by Inhibition of MTHFD2 in Colorectal Cancer: Mechanisms and Therapeutic Implications

Background

Overcoming oxidative stress is a critical step for tumor progression; however, the underlying mechanisms in colorectal cancer (CRC) remain unclear.

Methods

We investigated nicotinamide adenine dinucleotide (phosphate) (NAD(P))-dependent enzyme methylene tetrahydrofolate dehydrogenase 2 (MTHFD2) expression, clinical relevance, redox modification, and molecular mechanisms using the CRC cells and tissues (n = 462 paired samples). The antitumor effects of MTHFD2 inhibitor LY345899 on CRC tumorigenesis and metastasis were evaluated in vitro and in vivo. Data analysis used Kaplan-Meier, Pearson’s correlation, and Student t test where appropriate. All statistical tests were two-sided.

Results

Here, we report that the patients with high expression of MTHFD2 have a shorter overall survival (HR = 1.62, 95% CI = 1.12 to 2.36, P = .01) and disease-free survival (HR = 1.55, 95% CI = 1.07 to 2.27, P = .02) than patients with low MTHFD2 expression. Suppression of MTHFD2 disturbs NADPH and redox homeostasis and accelerates cell death under oxidative stress, such as hypoxia or anchorage independence (P ≤ .01 for all). Also, genetic or pharmacological inhibition of MTHFD2 suppresses CRC cell growth and lung and peritoneal metastasis in cell-based xenografts (n = 5–8 mice per group). Importantly, LY345899 treatment statistically significantly suppresses tumor growth and decreases the tumor weight in CRC patient-derived xenograft models (n = 10 mice per group, mean [SD] tumor weight of the vehicle-treated group was 1.83 [0.19] mg vs 0.74 [0.30] mg for the LY345899-treated group, P < .001)

Conclusions

Our study presents evidence that MTHFD2 confers redox homeostasis and promotes CRC cell growth and metastasis. The folate analog LY345899 as MTHFD2 inhibitor displays therapeutic activity against CRC and warrants further clinical investigation for CRC treatment.

Clinicopathological and Prognostic Characteristics of RAD51 in Colorectal Cancer

Background and Objectives: RAD51 plays an essential role in DNA repair via homologous recombination. RAD51 facilitates strand transfer between interrupted sequences and their undamaged homologies. Therefore, we studied the RAD51 mRNA expression levels in colorectal cancer (CRC), and evaluated the clinicopathological and prognostic significance of RAD51. Materials and Methods: The RAD51 expression was examined in 48 CRCs and paired adjacent non-tumor tissues. We further evaluated the survival to determine the prognostic value of RAD51 in our CRC and The Cancer Genome Atlas (TCGA) data. Results: We confirmed that the RAD51 expression in tumor tissues, compared with that of paired non-tumor tissues, was upregulated 2.5-fold. Additionally, the RAD51 expression was significantly associated with the T stage (p = 0.027). According to a higher T stage, the RAD51 expression showed an increasing trend. However, the RAD51 expression did not show a prognostic value statistically. Conclusions: We confirmed that RAD51 was upregulated in tumors and was significantly associated with the T stage. Although there was no statistically significant prognostic value found in our samples and TGCA data, our study will provide new insight for RAD51 in CRC.

AMPKα1 confers survival advantage of colorectal cancer cells under metabolic stress by promoting redox balance through the regulation of glutathione reductase phosphorylation

Patients with stage II or III colorectal cancer (CRC) exhibit various clinical outcomes after radical treatments. The 5-year survival rate was between 50 and 87%. However, the underlying mechanisms of the variation remain unclear. Here we show that AMPKα1 is overexpressed in CRC patient specimens and the high expression is correlated with poor patient survival. We further reveal a previously unrecognized function of AMPKα1, which maintains high level of reduced glutathione to keep reduction–oxidation reaction (redox) homeostasis under stress conditions, thus promoting CRC cell survival under metabolic stress in vitro and enhancing tumorigenesis in vivo. Mechanistically, AMPKα1 regulate the glutathione reductase (GSR) phosphorylation possibly through residue Thr507 which enhances its activity. Suppression of AMPKα1 by using nano-sized polymeric vector induces a favorable therapeutic effect, especially when in combination with oxaliplatin. Our study uncovers a novel function of AMPKα1 in redox regulation and identifies a promising therapeutic strategy for treatment of CRC.

A novel scoring system predicting survival benefits of palliative primary tumor resection for patients with unresectable metastatic colorectal cancer: A retrospective cohort study protocol

The role of palliative primary tumor resection (PPTR) in improving survival in patients with synchronous unresectable metastatic colorectal cancer (mCRC) is controversial. In this study, we aimed to evaluate whether our novel scoring system could predict survival benefits of PPTR in mCRC patients.In this retrospective cohort study consecutive patients with synchronous mCRC and unresectable metastases admitted to Sir Run Run Shaw Hospital between January 2005 and December 2013 were identified. A scoring system was established by the serum levels of carcinoembryonic antigen (CEA), cancer antigen 19-9 (CA19-9), neutrophil/lymphocyte ratio (NLR), and lactate dehydrogenase (LDH). Patients with scores of 0, 1-2, or 3-4 were considered as being in the low, intermediate, and high score group, respectively. Primary outcome was overall survival (OS).A total of 138 eligible patients were included in the analysis, of whom 103 patients had undergone PPTR and 35 had not. The median OS of the PPTR group was better than that of the Non-PPTR group, with 26.2 and 18.9 months, respectively (P < .01). However, the subgroup of PPTR with a high score (3-4) showed no OS benefit (13.3 months) compared with that of the Non-PPTR group (18.9 months, P = .11). The subgroup of PPTR with a low score (52.1 months) or intermediate score (26.2 months) had better OS than that of the Non-PPTR group (P < .001, P = .017, respectively).A novel scoring system composed of CEA, CA19-9, NLR, and LDH values is a feasible method to evaluate whether mCRC patients would benefit from PPTR. It might guide clinical decision making in selecting patients with unresectable mCRC for primary tumor resection.

Mass screening for colorectal cancer in a population of two million older adults in Guangzhou, China

Screening is an effective measure to prevent and control colorectal cancer (CRC). A mass CRC screening programme was conducted in Guangzhou from 2015 to 2017. Public media and reminders from a mobile short message service were used to invite residents aged between 50 and 74 years. A high-risk factor questionnaire (HRFQ) and biennial faecal immunochemical testing (FIT) were chosen as the primary screening methods, and individuals with a positive test result were referred to a defined hospital for an assessment colonoscopy. During the 3 years, 350,581 residents of the total eligible population of 2,283,214 attended the free first stage of screening. In all, 91.0% of the participants finished the HRFQs and FITs. The total uptake rate was 15.4%, which increased with age, female sex, and rural location. There was 15.9% positivity in the first stage of screening, including 8.5% positive HRFQs, 6.2% positive FITs and 1.2% positive HRFQs and FITs. In total, 10,600 individuals with positive HRFQs/FITs completed an assessment colonoscopy. The total uptake rate of colonoscopies was 18.9%, which decreased with age and female sex. Three hundred fifty-one CRCs and 980 advanced adenomas (AAs) were diagnosed with positive predictive values (PPV) of 3.3% and 9.2%, respectively. The PPVs of CRCs in the exclusively FIT-positive population were 4.9%, which was 10 times greater than in the exclusively HRFQ-positive population (0.5%). The PPVs of CRCs and AAs increased with age and male sex. The detection ratio of localized CRCs (including stage I and stage II) increased 68.1% due to screening. Although the compliance rate was low, the PPVs for CRCs and AAs were high. More effective mobilization of the programme's needs and subsidies for colonoscopies should be taken into account to increase compliance.

Analysis of population-based colorectal cancer screening in Guangzhou, 2011-2015

Objective

To analyze the detection rates of colorectal cancer (CRC) and polyps by population‐based screening in Guangzhou.

Methods

From January 2011 to December 2015, the residents aged 30‐79 were selected for CRC screening. The residents were conducted Questionnaires and/or FOBT to assess high‐risk groups, the free colonoscopy examination was recommended, and the results were evaluated in detail.

Results

There were 98 927 residents involving screening, 5306 high‐risk residents identified (males 1859 and females 3447), and 4713 subjects underwent colonoscopy (males 1690 and females 3023). CRC was seen in 55 individuals (males 28 and females 27), and the detection rates in male were higher than in female (P = 0.019). And the detection rates increasing with age, for people over 60 years old, were obviously higher than those younger (x² = 18.64, P = 0.000924).

The polyps were seen in 1458 (30.94%) cases， and 1420 subjects received pathological examination (adenomas 971 and non‐adenomatous polyps 449). Advanced adenomas were seen in 462 cases (males 240 and females 222) and 509 cases of non‐advanced adenomas (males 255 and females 254). For advanced adenomas, the detection rates in male were higher than female (14.20% vs 7.34%, P = 2.64 × 10⁻¹⁴). For the detection rates of adenomas or advanced adenomas by age, the people over 40 years were higher than younger (20.91% vs 3.61% P = 7.87 × 10⁻⁶; 9.94% vs 2.41%, P = 0.009).

Conclusions

For Guangzhou residents, the detection rates of CRC and adenoma were 1.17% and 20.60%. The detection rates of CRC increasing with age, for people over 60 years old, were obviously higher than those younger. But for people over 40 years, the detection rate of adenoma and advanced adenoma was higher than younger. So for people over 40 years, the CRC screening is recommended.

Demographic trends and KRAS/BRAFV600E mutations in colorectal cancer patients of South China: A single-site report

The incidence of colorectal cancer (CRC) is increasing in China. Here, we aimed to evaluate the latest demographic trends and KRAS/BRAF mutations status of Chinese CRC. Five thousand five hundred and forty-six CRC patients diagnosed from 2010 to 2017 were involved. KRAS exon 2 and BRAF^V600E mutations were detected by Sanger sequencing and high-resolution melting analysis or allelic-specific probe method. Gene mutation profiles and clinicopathologic characteristics of 5495 patients were analyzed. The joinpoint regression model was used to predict the demographic data in 2018. We found KRAS exon 2 and BRAF^V600E mutation rates were 37.7 and 2.8% in CRC patients. Tumors with KRAS exon 2 mutations were more likely to be present in female and patients aged older than 75 years, right colon and have well-differentiated histology. Tumors with BRAF^V600E mutations were more likely to be present in the female, right colon and have poorly differentiated histology. From 2010 to 2017, the percentage of colon cancer and tubular adenocarcinoma in CRC increased substantially (from 39.3 to 51.8%, from 78.6 to 93.4%, respectively). The percentage of right colon cancer increased from 18.3 to 20.5%, which predictively may keep at 22.6% in 2018. The rise trends for patients with moderate differentiation tumor or KRAS exon 2 mutated tumor were apparent (from 50.3 to 78.6%, from 32.8 to 39.7%, respectively). In conclusion, in recent 8 years, there is a shift to the colon, especially right colon in the incidence of Chinese CRC. Moreover tubular adenocarcinoma is becoming the primary histology type.

Trends in Colon and Rectal Cancer Incidence in Australia from 1982 to 2014: Analysis of Data on Over 375,000 Cases

BACKGROUND

Colorectal cancer is the third most commonly diagnosed cancer in Australia. Emerging evidence from several countries suggests increasing incidence in people aged <50 years.

METHODS

We assessed colon and rectal cancer incidence trends in people aged 20+ in Australia from 1982 to 2014. We used data on 375,008 incident cases (248,162 colon and 126,846 rectal). We quantified the annual percentage change (APC) in rates by age group using Joinpoint regression.

RESULTS

For people aged <50 years, colon cancer rates increased from the mid-2000s, with the increase in APCs ranging from 1.7% to 9.3% per annum (depending on specific age group); rectal cancer rates increased from the early 1990s, with APCs ranging from 0.9% to 7.1% per annum. For people aged 50 to 69 years, colon and rectal cancer rates decreased from the mid-1990s, with the decrease in APCs in specific age groups ranging from 0.8% to 4.8% per annum (except for colon cancer in those ages 65 to 69 years, where similar rate decreases were observed from 2007). An overall reduction in older persons (>70 years) was estimated at 1.9% to 4.9% per annum for colon cancer from 2010 onward and 1.1% to 1.8% per annum in rectal cancer from the early 2000s onward.

CONCLUSIONS

Colon and rectal cancer incidence has increased in people aged <50 years in Australia over the last two decades. However, colon and rectal cancer rates decreased in people aged 50+, likely due to de facto and organized bowel cancer screening.

IMPACT

Further research is needed to examine the cause of the increase and to quantify the impact of future trends on the cost-effectiveness of population-based screening for those <50 years.

Decreased expression of IDH1-R132H correlates with poor survival in gastrointestinal cancer

Isocitrate dehydrogenase (IDH1) is an NADP-dependent enzyme that catalyzes the decarboxylation of isocitrate to alpha-ketoglutarate. The IDH1-R132H mutation predicts a better clinical outcome for glioma patients, and the expression of IDH1-R132H correlates with a favorable outcome in patients with brain tumors. Here, we investigated IDH1-R132H expression in both gastric (n=526) and colorectal (n=399) tissues by performing immunohistochemistry analyses on tissue microarrays. We also tested whether IDH1-R132H expression correlated with various clinical parameters. In both gastric and colorectal cancer, expression of IDH1-R132H was associated with tumor stage. Patients with low IDH1-R132H expression had a poor overall survival. Our data indicate that IDH1-R132H expression could be used as a predictive marker of prognosis for patients with gastrointestinal cancer.

Caveolin-1 Inhibits Proliferation, Migration, and Invasion of Human Colorectal Cancer Cells by Suppressing Phosphorylation of Epidermal Growth Factor Receptor

Background

Although downregulation of caveolin-1 (Cav-1), which is a key constituent of membrane caveolae and a regulator of cellular processes, is associated with colorectal cancer (CRC), its involvement in the disease progression is largely unknown. This study aimed to explore the role of Cav-1 in CRC and the associated mechanisms.

Material/Methods

Fresh tissues from patients with CRC and human CRC SW480 cells were used to evaluate Cav-1 and Ki-67 expression using immunohistochemistry and Western blotting. The MTS and Transwell assays were performed to determine the effects of Cav-1 overexpression via pcDNA3.1/Cav-1 plasmid on cell proliferation and metastasis. The effect of Cav-1 on the epidermal growth factor receptor (EGFR) activation was evaluated by Western blotting. The correlation of Cav-1 expression with clinicopathological factors was statistically analyzed.

Results

Overexpression of Cav-1 significantly reduced proliferation, migration, and invasion of SW480 cancer cells in vitro. The EGF-induced phosphorylation of EGFR and activations of the RAF-MEK-ERK and PI3K-AKT pathways were adversely regulated by Cav-1 overexpression in vitro. In 76 cases of CRC patients with EGFR expression, a negative correlation was observed between the level of Cav-1 and tumor-node-metastasis stage, lymph node metastasis, and distant metastasis (All p<0.05). Finally, the expression level of Cav-1 was negatively correlated with that of Ki-67.

Conclusions

This report is the first to show that overexpression of Cav-1significantly inhibits the proliferation, migration, and invasion potential of SW480 cells, possibly through reducing EGF-induced EGFR activation. High Cav-1 expression level may be a predictor of positive outcomes in patients with colorectal cancer.

Disrupting G6PD-mediated Redox homeostasis enhances chemosensitivity in colorectal cancer

Glucose-6-phosphate dehydrogenase (G6PD) is a key enzyme that generates NADPH to maintain reduced glutathione (GSH), which scavenges reactive oxygen species (ROS) to protect cancer cell from oxidative damage. In this study, we mainly investigate the potential roles of G6PD in colorectal cancer (CRC) development and chemoresistance. We discover that G6PD is overexpressed in CRC cells and patient specimens. High expression of G6PD predicts poor prognosis and correlated with poor outcome of oxaliplatin-based first-line chemotherapy in patients with CRC. Suppressing G6PD decreases NADPH production, lowers GSH levels, impairs the ability to scavenge ROS levels, and enhances oxaliplatin-induced apoptosis in CRC via ROS-mediated damage in vitro. In vivo experiments further shows that silencing G6PD with lentivirus or non-viral gene delivery vector enhances oxaliplatin anti-tumor effects in cell based xenografts and PDX models. In summary, our finding indicated that disrupting G6PD-mediated NADPH homeostasis enhances oxaliplatin-induced apoptosis in CRC through redox modulation. Thus, this study indicates that G6PD is a potential prognostic biomarker and a promising target for CRC therapy.

Spatio-temporal analysis of the incidence of colorectal cancer in Guangzhou, 2010-2014

INTRODUCTION

Colorectal cancer (CRC) is a common type of neoplasm. This study examined the spatio-temporal distribution of the CRC incidence in Guangzhou during 2010-2014.

METHODS

Colorectal cancer incidence data were obtained from the Guangzhou Cancer Registry System. Spatial autocorrelation analysis and a retrospective spatio-temporal scan were used to assess the spatio-temporal cluster distribution of CRC cases.

RESULTS

A total of 14,618 CRC cases were registered in Guangzhou during 2010-2014, with a crude incidence of 35.56/100,000 and an age-standardized rate of incidence by the world standard population (ASRIW) of 23.58/100,000. The crude incidence increased by 19.70% from 2010 (32.88/100,000) to 2014 (39.36/100,000) with an average annual percentage change (AAPC) of 4.33%. The AAPC of ASRIW was not statistically significant. The spatial autocorrelation analysis revealed a CRC incidence hot spot in central urban areas in Guangzhou City, which included 25 streets in southwestern Baiyun District, northwestern Haizhu District, and the border region between Liwan and Yuexiu Districts. Three high- and five low-incidence clusters were identified according to spatio-temporal scan of CRC incidence clusters. The high-incidence clusters were located in central urban areas including the border regions between Baiyun, Haizhu, Liwan, and Yuexiu Districts.

CONCLUSIONS

This study revealed the spatio-temporal cluster pattern of the incidence of CRC in Guangzhou. This information can inform allocation of health resources for CRC screening.

Evolution of Cancer Registration Combining Online Reporting with Follow-up in the Community: Practices in Guangzhou, China

Background:

An efficient registration system with accurate and timely information on cancer incidence and mortality is key to development of policies to prevent and control cancer. A traditional registration system usually needs 3-4 years to collect data and publish a cancer report. However, researchers, policymakers and healthcare professionals need to know the latest cancer registration data quickly.

Methods:

A computer system has been operating with cases reported online by hospitals and followed up in communities at the Cancer Registry of Guangzhou (CRG) since 2008. The comparability, completeness, accuracy and timeliness of collected data were here evaluated.

Results:

From 2010 to 2014, 181,194 cancer cases from 1,916,253 medical records of cancer were reported to the CRG online. 53,473 cases were deleted as duplicates (47,906), wrong diagnoses (410) or residents of other places (5,157) during the follow up. Successful final follow-up rates were over 90% for both newly and previously diagnosed cases by general practitioners in community clinics. The CRG coding and classification system follows international standards. The annual trends for all sites by sex were stable from 2010 to 2014. All age-specific incidence rates for childhood cancers were within the limits of the respective international references. The overall M: I ratio for all sites but C44 was 56.7%., ratios for most sites in Guangzhou being between Hong Kong and Shanghai. A total of 75.7% of the cancer cases reported in 2010–2012 were morphologically verified. Ninety five percent of new cases completed registration within 29.0 months in 2010, reducing to 8.0 months in 2014.

Conclusion:

The online report system with community follow up at the CRG yields reasonably accurate and close-to-complete data. It takes less time to confirm diagnosis and other information so that reporting annual incidence one year after the close of registration becomes possible.

Overuse of colorectal cancer screening services in the United States and its implications

As a standard way for prevention and early detection of colorectal cancer (CRC), colonoscopy has been used for CRC screening in the United States for more than one decade. An article entitled “Assessing Colorectal Cancer Screening Adherence of Medicare Fee-For-Service Beneficiaries Age 76 to 95 Years” recently published at the Journal of Oncology Practice reports the trends in overuse of CRC screening services among average-risk elderly populations at the age of 76–95 years. Several reasons for overusing colonoscopy have been postulated, and some strategies for reducing overuse of CRC screening services have also been proposed.

Leveraging the power of pooled data for cancer outcomes research

Background

Clinical trials continue to be the gold standard for determining the efficacy of novel cancer treatments, but they may also expose participants to the potential risks of unpredictable or severe toxicities. The development of validated tools that better inform patients of the benefits and risks associated with clinical trial participation can facilitate the informed consent process. The design and validation of such instruments are strengthened when we leverage the power of pooled data analysis for cancer outcomes research.

Main body

In a recent study published in the Journal of Clinical Oncology entitled “Determinants of early mortality among 37,568 patients with colon cancer who participated in 25 clinical trials from the adjuvant colon cancer endpoints database,” using a large pooled analysis of over 30,000 study participants who were enrolled in clinical trials of adjuvant therapy for early-stage colon cancer, we developed and validated a nomogram depicting the predictors of early cancer mortality. This database of pooled individual-level data allowed for a comprehensive analysis of poor prognostic factors associated with early death; furthermore, it enabled the creation of a nomogram that was able to reliably capture and quantify the benefit-to-risk profile for patients who are considering clinical trial participation. This tool can facilitate treatment decision-making discussions.

Conclusion

As China and other Asian countries continue to conduct oncology clinical trials, efforts to collate patient-level information from these studies into a large data repository should be strongly considered since pooled data can increase future capacity for cancer outcomes research, which, in turn, can enhance patient-physician discussions and optimize clinical care.

Outcomes of preoperative chemoradiotherapy followed by surgery in patients with unresectable locally advanced sigmoid colon cancer

BACKGROUND

Complete resection of locally advanced sigmoid colon cancer (LASCC) is sometimes difficult. Patients with LASCC have a dismal prognosis and poor quality of life, which has encouraged the evaluation of alternative multimodality treatments. This prospective study aimed to assess the feasibility and efficacy of neoadjuvant chemoradiotherapy (neoCRT) followed by surgery as treatment of selected patients with unresectable LASCC.

METHODS

We studied the patients with unresectable LASCC who received neoCRT followed by surgery between October 2010 and December 2012. The neoadjuvant regimen consisted of external-beam radiotherapy to 50 Gy and capecitabine-based chemotherapy every 3 weeks. Surgery was scheduled 6-8 weeks after radiotherapy.

RESULTS

Twenty-one patients were included in this study. The median follow-up was 42 months (range, 17-57 months). All patients completed neoCRT and surgery. Resection with microscopically negative margins (R0 resection) was achieved in 20 patients (95.2%). Pathologic complete response was observed in 8 patients (38.1%). Multivisceral resection was necessary in only 7 patients (33.3%). Two patients (9.5%) experienced grade 2 postoperative complications. No patients died within 30 days after surgery. For 18 patients with pathologic M0 (ypM0) disease, the cumulative probability of 3-year local recurrence-free survival, disease-free survival and overall survival was 100.0%, 88.9% and 100.0%, respectively. For all 21 patients, the cumulative probability of 3-year overall survival was 95.2% and bladder function was well preserved.

CONCLUSION

For patients with unresectable LASCC, preoperative chemoradiotherapy and surgery can be performed safely and may result in an increased survival rate.

Palliative primary tumor resection provides survival benefits for the patients with metastatic colorectal cancer and low circulating levels of dehydrogenase and carcinoembryonic antigen

BACKGROUND

It remains controversial whether palliative primary tumor resection (PPTR) can provide survival benefits to the patients with metastatic colorectal cancer (mCRC) who have unresectable metastases. The aim of this study was to evaluate whether PPTR could improve the survival of patients with mCRC.

METHODS

We conducted a retrospective study on consecutive mCRC patients with unresectable metastases who were diagnosed at Sun Yat-sen University Cancer Center in Guangzhou, Guangdong, China, between January 2005 and December 2012. Overall survival (OS) and progression-free survival (PFS) after first-line chemotherapy failure were compared between the PPTR and non-PPTR patient groups.

RESULTS

A total of 387 patients were identified, including 254 who underwent PPTR and 133 who did not. The median OS of the PPTR and non-PPTR groups was 20.8 and 14.8 months (P < 0.001), respectively. The median PFS after first-line chemotherapy was 7.3 and 4.8 months (P < 0.001) in the PPTR and non-PPTR groups, respectively. A larger proportion of patients in the PPTR group (219 of 254, 86.2%) showed local progression compared with that of patients in the non-PPTR group (95 of 133, 71.4%; P < 0.001). Only patients with normal lactate dehydrogenase (LDH) levels and with carcinoembryonic antigen (CEA) levels <70 ng/mL benefited from PPTR (median OS, 22.2 months for the PPTR group and 16.2 months for the non-PPTR group; P < 0.001).

CONCLUSIONS

For mCRC patients with unresectable metastases, PPTR can improve OS and PFS after first-line chemotherapy and decrease the incidence of new organ involvement. However, PPTR should be recommended only for patients with normal LDH levels and with CEA levels <70 ng/mL.

Inhibition of the NF-κB pathway by nafamostat mesilate suppresses colorectal cancer growth and metastasis

Nafamostat mesilate is an anti-inflammatory drug that is usually used to treat pancreatitis. Recent studies show that it can suppress pancreatic cancer via inhibition of the nuclear factor κB (NF-κB) pathway. However, whether it has anti-tumor activity in some other cancer, including colorectal cancer (CRC), has not been investigated and remained unclear. Here, our study showed that nafamostat mesilate abrogated the constitutive NF-κB activation in CRC cells, which is mediated through inhibition of phosphorylation of IκBα and nuclear translocation of p65. Also, we found that nafamostat mesilate inhibited phosphorylation of Erk in CRC cells. Consistently, our study demonstrated that nafamostat mesilate inhibited the CRC cell proliferation, invasion and migration and induced mitochondria-dependent apoptosis. Furthermore, nafamostat mesilate could reverse oxaliplatin induced NF-κB and Erk activation in CRC cells, and enhance the sensitivity of CRC cells to oxaliplatin. Nafamostat mesilate combined with oxaliplatin repressed subcutaneous tumor growth and hepatic metastasis in vivo. Overall, our data suggest that nafamostat mesilate, a relatively non-toxic drug that targets NF-κB and Erk, may, in combination with oxaliplatin, represent a novel therapeutic strategy for CRC treatment.

Redox Regulation of Stem-like Cells Though the CD44v-xCT Axis in Colorectal Cancer: Mechanisms and Therapeutic Implications

Colorectal cancer (CRC) is a common neoplastic disease and a frequent cause of death. Drug resistance is a major challenge to CRC treatment and stem-like side-population (SP) cells may play a key role in this resistance. Although it has been recognized that cancer stem cells may be affected by redox status, the underlying mechanisms for this effect and the roles of celllular redox adaptation and antioxidant capacity in CRC remain elusive. Our study shows that CRC SP cells are highly dependent on cellular GSH to maintain ROS levels below those of non-SP cells. Exposing CRC cells to H2O2 produced a significant decrease in the percentage of SP cells, which was rescued by adding N-acetylcysteine. Mechanistically, CD44v interacts with and stabilizes xCT and thereby promotes the uptake of cysteine for GSH synthesis and stimulates SP cell enrichment. Additionally, miR-1297 levels were inversely correlated with the expression of xCT; thus, reduced miR-1297 contributes to SP cell enrichment in CRC tumors, which results in tumor aggressiveness and poor clinical outcomes. Importantly, redox modification by PEITC significantly reduces CRC SP cells in vitro and impairs tumors growth in vivo. The combination of 5FU and PEITC led to synergistic cytotoxic effects against CRC cells in vitro and in vivo. Taken together, our data suggest that a GSH-mediated reduction in cellular ROS levels is an essential regulator of CRC SP cells mediated by the CD44v-xCT axis, and disrupting the redox status may eliminate the chemotherapy-resistant CRC SP cells with potentially significant benefits for cancer treatment.

Association of perioperative blood pressure with long-term survival in rectal cancer patients

Background

Several studies suggested that hypertension is positively related to cancer incidence and mortality. In this study, we investigated the association between perioperative blood pressure (BP) and long-term survival outcomes in patients with rectal cancer.

Methods

This study included a cohort of 358 patients with stages I–III rectal cancer who underwent a curative resection between June 2007 and June 2011. Both pre- and postoperative BPs were measured, by which patients were grouped (low BP: <120/80 mmHg; high BP: ≥120/80 mmHg). The survival outcomes were compared between these two groups. The primary endpoints were disease-free survival (DFS) and cancer-specific survival (CSS).

Results

Univariate analysis showed that patients with high preoperative systolic BP had lower 3-year DFS (67.2% vs. 82.1%, P = 0.041) and CSS rates (81.9% vs. 94.8%, P = 0.003) than patients with low preoperative systolic BP, and the associations remained significant in the Cox multivariate analysis, with the adjusted hazard ratios equal to 1.97 [95% confidence interval (CI) = 1.08–3.60, P = 0.028] and 2.85 (95% CI = 1.00–8.25, P = 0.050), respectively. Similarly, in postoperative evaluation, patients with high systolic BP had significantly lower 3-year CSS rates than those with low systolic BP (78.3% vs. 88.9%, P = 0.032) in univariate analysis. Moreover, high pre- and/or postoperative systolic BP presented as risk factors for CSS in the subgroups of patients who did not have a history of hypertension, with and/or without perioperative administration of antihypertensive drugs.

Conclusions

High preoperative systolic BP was an independent risk factor for both CSS and DFS rates, and high postoperative systolic BP was significantly associated with a low CSS rate in rectal cancer patients. Additionally, our results suggest that rectal cancer patients may get survival benefit from BP control in perioperative care. However, further studies should be conducted to determine the association between BP and CSS and targets of BP control.

Effect of preoperative injection of carbon nanoparticle suspension on the outcomes of selected patients with mid-low rectal cancer

BACKGROUND

Carbon nanoparticles show significant lymphatic tropism and can be used to identify lymph nodes surrounding mid-low rectal tumors. In this study, we analyzed the effect of trans anal injection of a carbon nanoparticle suspension on the outcomes of patients with mid-low rectal cancer who underwent laparoscopic resection.

METHODS

We collected the data of 87 patients with mid-low rectal cancer who underwent laparoscopic resection between November 2014 and March 2015 at Cancer Hospital, Chinese Academy of Medical Sciences & Peking Union Medical College. For 35 patients in the experimental group, the carbon nanoparticle suspension was injected transanally into the submucosa of the rectum around the tumor 30 min before the operation; 52 patients in the control group underwent the operation directly without the injection of carbon nanoparticle suspension. We then compared the operation outcomes between the two groups.

RESULTS

In the experimental group, the rate of incomplete mesorectal excision was lower than that in the control group, but no significant difference was found (2.9% vs. 7.7%, P = 0.342). The distance between the tumor and the circumferential resection margin was 5.8 ± 1.4 mm in the experimental group and 4.8 ± 1.1 mm in the control group (P = 0.001). The mean number of lymph nodes removed was 28.2 ± 9.4 in the experimental group and 22.7 ± 7.3 in the control group (P = 0.003); the mean number of lymph nodes smaller than 5 mm in diameter was 10.1 ± 7.5 and 4.5 ± 3.7, respectively (P < 0.001). Three patients in the experimental group received lateral lymph node resection. Among the three patients, we retrieved three nodes (one stained node) from the first patient, three nodes (two stained nodes) from the second patient, and two nodes (no stained nodes) from the third patient.

CONCLUSIONS

Injecting a carbon nanoparticle suspension improved the outcomes of patients who underwent laparoscopic resection for mid-low rectal cancer; it also improved the accuracy of pathologic staging. Moreover, for selected patients, this technique narrowed the scope of lateral lymph node dissection.

Prognostic significance of the pre-chemotherapy lymphocyte-to-monocyte ratio in patients with previously untreated metastatic colorectal cancer receiving FOLFOX chemotherapy

Background

As a surrogate marker of systemic inflammation, the lymphocyte-to-monocyte ratio (LMR) is an independent prognostic factor for various malignancies. This study investigated the prognostic significance of the pre-chemotherapy LMR in patients with previously untreated metastatic colorectal cancer (mCRC) receiving chemotherapy.

Methods

The present study included newly diagnosed mCRC patients treated between January 2005 and December 2013 with FOLFOX chemotherapy, specifically oxaliplatin 180 mg/m² on day 1, with leucovorin 400 mg/m² administered as a 2-hour infusion before the administration of 5-fluorouracil 400 mg/m² as an intravenous bolus injection, and 5-fluorouracil 2400 mg/m² as a 46-h infusion immediately after 5-fluorouracil bolus injection. The LMR was calculated as the absolute count of lymphocytes divided by the absolute count of monocytes. COX proportional hazards analysis was performed to evaluate the association of LMR with survival outcomes.

Results

A total of 488 patients were included. Patients with high pre-chemotherapy LMR experienced significant improvements in progression-free survival (PFS, 9.2 vs. 7.6 months, P < 0.001) and overall survival (OS, 19.4 vs. 16.6 months, P < 0.001) compared with patients with low pre-chemotherapy LMR. Subsequent COX multivariate analysis showed that high pre-chemotherapy LMR (≥3.11) was an independent favorable prognostic factor for PFS and OS. Additionally, patients whose LMR remained high (high–high subgroup), increased (low–high subgroup), or decreased (high–low subgroup) following chemotherapy showed better results in terms of PFS and OS than patients whose LMR remained low (low–low subgroup) after chemotherapy.

Conclusions

For patients with previously untreated mCRC receiving FOLFOX chemotherapy, an elevated pre-chemotherapy LMR is an independent favorable prognostic factor for PFS and OS, and changes in the LMR before and after chemotherapy seem to predict the benefit of chemotherapy.