Patterns of Colorectal Cancer Care in the United States: 1990-2010

Nomogram model for predicting cancer-specific mortality in patients with early-onset colorectal cancer: a competing risk analysis insight from the SEER database and an external validation cohort

Background

Early-onset colorectal cancer (EOCRC) is increasing in incidence and poses a growing threat. Urgent research is needed, especially in survival analysis, to enhance comprehension and treatment strategies. This study aimed to explore the risk factors associated with cancer-specific mortality (CSM) and other-cause mortality (OCM) in patients with EOCRC. Additionally, the study aimed to develop a nomogram predicting CSM using a competitive risk model and validate its accuracy through the use of training, using internal and external cohorts.

Methods

Data from EOCRC patients were collected from the Surveillance, Epidemiology, and End Results (SEER) database (2008-2017). EOCRC patients who were treated at a tertiary hospital in northeast China between 2014 and 2020 were also included in the study. The SEER data were divided into the training and validation sets at a 7:3 ratio. A univariate Cox regression model was employed to identify prognostic factors. Subsequently, multivariate Cox regression models were applied to ascertain the presence of independent risk factors. A nomogram was generated to visualize the results, which were evaluated using the concordance index (C-index), area under the curve (AUC), and calibration curves. The clinical utility was assessed via decision curve analysis (DCA).

Results

Multivariable Cox regression analysis demonstrated that factors such as race, tumor differentiation, levels of carcinoembryonic antigen (CEA), marital status, histological type, American Joint Committee on Cancer (AJCC) stage, and surgical status were independent risk factors for CSM in EOCRC patients. In addition, age, gender, chemotherapy details, CEA levels, marital status, and AJCC stage were established as independent risk factors for OCM in individuals diagnosed with EOCRC. A nomogram was developed using the identified independent risk factors, demonstrating excellent performance with a C-index of 0.806, 0.801, and 0.810 for the training, internal validation, and external validation cohorts, respectively. The calibration curves and AUC further confirmed the accuracy and discriminative ability of the nomogram. Furthermore, the DCA results indicated that the model had good clinical value.

Conclusions

In this study, a competing risk model for CSM was developed in EOCRC patients. The model demonstrates a high level of predictive accuracy, providing valuable insights into the treatment decision-making process.

Survival trends for left and right sided colon cancer using population-based SEER database: A forty-five-year analysis from 1975 to 2019

BACKGROUND

Survival differences between left-sided colon cancer (LSCC) and right-sided colon cancer (RSCC) has been previously reported with mixed results, with various study periods not accounting for other causes of mortality.

PURPOSE

We sought to assess the trends in colon cancer cause- specific survival (CSS) and overall survival (OS) based on sidedness.

METHOD

Fine-Gray competing risk and Cox models were used to analyze Surveillance, Epidemiology, and End Results (SEER) population-based cohort from 1975 to 2019. Various interval periods were identified based on the timeline of clinical adoption of modern chemotherapy (1975-1989, interval period A; 1990-2004, B; and 2005-2019, C).

RESULTS

Of the 227,637 patients, 50.1% were female and 46.2% were RSCC. RSCC was more common for African Americans (51.5%), older patients (age ≥65; 51.4%), females (50.4%), while LSCC was more common among Whites (53.1%; p < 0.001), younger patients (age 18-49, 64.6%; 50-64, 62.3%; p < 0.001), males (58.1%; p < 0.001). The Median CSS for LSCC and RCC were 19.3 and 16.7 years respectively for interval period A (1975-1989). Median CSS for interval periods B and C were not reached (more than half of the cohort was still living at the end of the follow-up period). Adjusted CSS was superior for LSCC versus RSCC for the most recent interval period C (HR 0.89; 0.86-0.92; p < 0.001). LSCC consistently showed superior OS for all study periods. Stage stratification showed worse CSS for localized and regional LSCC in the earlier study periods, but the risk attenuated over time. However, left sided distant disease had superior CSS per stage for all interval periods. OS was better for LSCC irrespective of stage, with gradual improvement over time.

CONCLUSION

LSCC was associated with superior survival compared to right sided tumors. With the adoption of modern chemotherapy regimens, prognosis between LSCC and RSCC became more divergent in favor of LSCC. Colon cancer clinical trials should strongly consider tumor sidedness as an enrollment factor.

Differential clinical outcomes after 3 versus 5 years in a comparison of preoperative chemotherapy with and without radiotherapy in locally advanced rectal cancer: A national cohort propensity score-matched study

Background

Preoperative chemotherapy alone might be a good alternative to preoperative chemoradiotherapy for patients with locally advanced rectal cancer, yet long-term real-world data from the same cohort are lacking.

Methods

Patients diagnosed with stage II-III rectal adenocarcinoma from 2011 to 2015 were randomly sampled from the SEER-Plus database to evaluate the superiority of preoperative chemoradiotherapy versus preoperative chemotherapy alone.

Findings

A total of 1314 eligible patients were enrolled, with a median follow-up of 74.0 months. At 3-year follow-up, neither overall survival (OS) nor cancer-specific survival (CSS) was significantly different between the two treatment groups. At 5-year follow-up, CSS was similar across groups (HR 0.768, 95% CI 0.532-1.108; P = 0.156), but the 5-year OS was significantly better in the preoperative chemoradiotherapy group than in the preoperative chemotherapy group (HR 0.682, 95% CI 0.538-0.866; P = 0.002). Besides, the landmark analysis indicated a direct contrast in the CSS within 3 years (HR 1.101, 95% CI 0.598-2.029; P = 0.756) versus that at 3-5 years (HR 0.597, 95% CI 0.377-0.948; P = 0.027). The landmark analysis also showed directly contrasting OS outcomes within 3 years (HR 0.761, 95% CI 0.533-1.086; P = 0.130) versus those at 3-5 years (HR 0.621, 95% CI 0.451-0.857; P = 0.003).

Interpretation

In patients with locally advanced rectal cancer under real-world treatment practices, the addition of preoperative radiotherapy to chemotherapy improves survival outcomes at 3-5 years' follow-up but not at 3-year follow-up.

Visualizing External Validity: Graphical Displays to Inform the Extension of Treatment Effects from Trials to Clinical Practice

BACKGROUND

In the presence of effect measure modification, estimates of treatment effects from randomized controlled trials may not be valid in clinical practice settings. The development and application of quantitative approaches for extending treatment effects from trials to clinical practice settings is an active area of research.

METHODS

In this article, we provide researchers with a practical roadmap and four visualizations to assist in variable selection for models to extend treatment effects observed in trials to clinical practice settings and to assess model specification and performance. We apply this roadmap and visualizations to an example extending the effects of adjuvant chemotherapy (5-fluorouracil vs. plus oxaliplatin) for colon cancer from a trial population to a population of individuals treated in community oncology practices in the United States.

RESULTS

The first visualization screens for potential effect measure modifiers to include in models extending trial treatment effects to clinical practice populations. The second visualization displays a measure of covariate overlap between the clinical practice populations and the trial population. The third and fourth visualizations highlight considerations for model specification and influential observations. The conceptual roadmap describes how the output from the visualizations helps interrogate the assumptions required to extend treatment effects from trials to target populations.

CONCLUSIONS

The roadmap and visualizations can inform practical decisions required for quantitatively extending treatment effects from trials to clinical practice settings.

The Effect of a Temporary Stoma on Long-term Functional Outcomes Following Surgery for Rectal Cancer

BACKGROUND

Patients with rectal cancer may undergo surgical resection with or without a temporary stoma.

OBJECTIVE

This study primarily aimed to compare long-term functional outcomes between patients with and without a temporary stoma after surgery for rectal cancer. The secondary aim was to investigate the effect of time to stoma reversal on functional outcomes.

DESIGN

This was a multicenter, cross-sectional study.

SETTINGS

This study was conducted at 7 Dutch hospitals.

PATIENTS

Included were patients who had undergone rectal cancer surgery (2009-2015). Excluded were deceased patients, who were deceased, had a permanent stoma, or had intellectual disability.

MAIN OUTCOME MEASURES

Functional outcomes were measured using the Rome IV criteria for constipation and fecal incontinence and the low anterior resection syndrome score.

RESULTS

Of 656 patients, 32% received a temporary ileostomy and 20% a temporary colostomy (86% response). Follow-up was at 56 (interquartile range, 38.5-79) months. Patients who had a temporary ileostomy experienced less constipation, more fecal incontinence, and more major low anterior resection syndrome than those without a temporary stoma. Patients who had a temporary colostomy experienced more major low anterior resection syndrome than those without a temporary stoma. A temporary ileostomy or colostomy was not associated with constipation or fecal incontinence after correction for confounding factors (eg, anastomotic height, anastomotic leakage, radiotherapy). Time to stoma reversal was not associated with constipation, fecal incontinence, or major low anterior resection syndrome.

LIMITATIONS

Cross-sectional design.

CONCLUSIONS

Although patients with a temporary ileostomy or colostomy have worse functional outcomes in the long term, it seems that the reason for creating a temporary stoma, rather than the stoma itself, underlies this phenomenon. Time to reversal of a temporary stoma does not influence functional outcomes. See Video Abstract .

EL EFECTO DEL ESTOMA TEMPORAL SOBRE LOS RESULTADOS FUNCIONALES A LARGO PLAZO DESPUS DE LA CIRUGA POR CNCER DE RECTO

ANTECEDENTES:Los pacientes con cáncer de recto pueden someterse a resección quirúrgica con o sin un estoma temporal.OBJETIVO:El objetivo principal de este estudio fue comparar los resultados funcionales a largo plazo entre pacientes con y sin estoma temporal después de cirugía por cáncer de recto. El objetivo secundario fue investigar el efecto del tiempo transcurrido hasta la reversión del estoma sobre los resultados funcionales.DISEÑO:Este fue un estudio transversal multicéntrico.ESCENARIO:Este estudio se llevó a cabo en siete hospitales holandeses.PACIENTES:Se incluyeron pacientes sometidos a cirugía de cáncer de recto (2009-2015). Se excluyeron pacientes fallecidos, pacientes con estoma permanente o discapacidad intelectual.PRINCIPALES MEDIDAS DE RESULTADO:Los resultados funcionales se midieron utilizando los criterios de Roma IV para el estreñimiento y la incontinencia fecal y la puntuación del síndrome de resección anterior baja (LARS).RESULTADOS:De 656 pacientes, el 32% recibió una ileostomía temporal y el 20% una colostomía temporal (respuesta del 86%). El seguimiento fue de 56.0 (RIQ 38.5-79.0) meses. Los pacientes a los que se les realizó una ileostomía temporal experimentaron menos estreñimiento, más incontinencia fecal y más LARS mayor que los pacientes sin un estoma temporal. Los pacientes que tuvieron una colostomía temporal experimentaron más LARS mayor que los pacientes sin un estoma temporal. Una ileostomía o colostomía temporal no se asoció con estreñimiento o incontinencia fecal después de la corrección de factores de confusión (p. ej., altura anastomótica, fuga anastomótica, radioterapia). El tiempo hasta la reversión del estoma no se asoció con estreñimiento, incontinencia fecal o LARS mayor.LIMITACIONES:El presente estudio está limitado por su diseño transversal.CONCLUSIONES:Aunque los pacientes con una ileostomía o colostomía temporal tienen peores resultados funcionales a largo plazo, parece que la razón para crear un estoma temporal, más que el estoma en sí, se asocia a este fenómeno. El tiempo hasta la reversión de un estoma temporal no influye en los resultados funcionales. (Traducción-Dr. Jorge Silva Velazco ).

New findings in prognostic factor assessment for adenocarcinoma of transverse colon: a comparison study between competing-risk and COX regression analysis

Purpose

Competing-risk analysis was used to accurately assess prognostic factors for cancer-specific death in patients with adenocarcinoma of transverse colon (ATC), and the results were compared with those from a conventional Cox regression analysis.

Materials and Methods

Patients diagnosed with ATC between 2000 and 2019 were selected from the Surveillance, Epidemiology, and End Results database. The crude mortality rates of patients with ATC were calculated and their differences were tested using the Gray's test, respectively. In performing multivariate analysis, the Cox regression model and the subdistribution hazard function (SD) in competing risk analysis were utilized, respectively.

Results

This study included 21,477 eligible patients. The SD model indicated that age, etc. are actual independent prognostic factors. In contrast to previous recognition, the results of the Cox regression showed false-positives for sex and Carcinoembryonic antigen, and underestimated point-estimates in the stage and American Joint Committee on Cancer stage due to competing events. A detailed comparison of treatment revealed that the larger surgical scopes were prognostic risk factors compared with the smaller scope of local tumor excision, partial colectomy, or segmental resection. Patients treated with external proton beam radiotherapy had an increased risk compared with those with no radiotherapy and internal radiotherapy.

Conclusions

After comparing the results of the two methods and mitigating the significant bias introduced by Cox regression, we found independent factors that really affect the prognosis of ATC. On the other hand, in terms of ATC, a larger surgical scope and external proton beam radiotherapy may not improve the long-term survival of patients. Therefore, when faced with ATC patients, these differences should be noted and treated differently from common colorectal cancer patients. Thus, clinicians are able to give more targeted treatment plans and prognostic assessments.

Adjuvant Radiotherapy Is Not Necessary for Stage III Mucinous Rectal Cancer: Evidence Based on Long Survival Analysis from SEER Data

BACKGROUND

Although rectal mucinous adenocarcinoma (RMC) is less sensitive to radiotherapy, adjuvant radiotherapy is still recommended for RMC patients. This study aimed to explore whether adjuvant radiotherapy is necessary for stage III RMC.

METHODS

Data of patients with stage III RMC were obtained from the National Cancer Institute's SEER database (2004-2015). The survival rates were calculated by Kaplan-Meier method and compared by log-rank test. Univariate and multivariate Cox regression analyses were used to assess the impact of clinicopathological parameters on overall survival (OS) and cancer-specific survival (CSS).

RESULTS

RMC has a worse T and N stage at diagnosis than rectal adenomatous carcinoma (RAC) (all p < 0.001). Multivariate Cox regression analyses revealed that histopathological type MC was an independent poor prognostic factor for OS (HR 1.27; 95%CI 1.14-1.41; p < 0.001) and CSS (HR 1.34; 95%CI 1.18-1.51; p < 0.001). Subgroup analysis based on different treatment regimens showed no significant difference between chemotherapy group and chemotherapy plus radiotherapy group. After the propensity score matching, no significant difference was also found in OS and CSS between chemotherapy group and chemotherapy plus radiotherapy group.

CONCLUSIONS

RMC is an independent poor prognostic factor for OS and CSS. Adjuvant radiotherapy for RMC was not beneficial in improving survival outcomes.

Quality of life, effectiveness, and safety of aflibercept plus FOLFIRI in older patients with metastatic colorectal cancer: An analysis of the prospective QoLiTrap study

INTRODUCTION

Colorectal cancer (CRC) mainly affects older patients. The pivotal VELOUR phase III trial of aflibercept plus FOLFIRI in metastatic CRC (mCRC) included only 5.9% of patients aged ≥75 years. Herein, we report a preplanned analysis from QoLiTrap, a large prospective observational study evaluating the impact of age on quality of life (QoL), effectiveness, and safety of aflibercept plus FOLFIRI in daily clinical practice in Europe.

MATERIALS AND METHODS

Enrolled patients had progressive mCRC, had failed a prior oxaliplatin-based regimen, and had received aflibercept (4 mg/kg) plus FOLFIRI every two weeks until disease progression, death, unacceptable toxicity, or physician/patient decision. Analyses were performed by age classes (<60, 60-64, 65-69, 70-74, and ≥ 75 years). The primary endpoint was the percentage of patients whose global health status (GHS) of the European Organization for the Research and Treatment of Cancer Quality of Life Questionnaire (EORTC QLQ-C30) was maintained (i.e., no worsening from baseline by at least 5% over a 12-week treatment). Secondary endpoints included tumor objective response rate (ORR), progression-free survival (PFS), overall survival (OS), and safety.

RESULTS

Overall, 1277 patients (<60 years, n = 327; 60-64 years, n = 231; 65-69 years, n = 227; 70-74 years, n = 259; and ≥ 75 years, n = 233) were treated, of whom 872 were evaluable for QoL. GHS was maintained in 36.5%, 41.6%, 38.9%, 41.8%, and 44.8% of patients aged <60, 60-64, 65-69, 70-74, and ≥ 75 years, respectively. Age did not influence PFS (median 7.8 months), OS (median 14.4 months), or ORR (20.8%). Number of cycles, dose delays for any cause, and dose reductions for adverse events (AEs) were comparable between age classes. Grade ≥ 3 AEs occurred in 47.7%, 51.9%, 51.5%, 55.2%, and 55.8% of patients aged <60, 60-64, 65-69, 70-74, and ≥ 75 years, respectively. The main grade ≥ 3 AEs were hypertension (11.2%) and diarrhea (9%) in patients aged ≥75 years.

DISCUSSION

The results suggest that aflibercept plus FOLFIRI maintains QoL and retains its activity, including a high objective tumor response, regardless of age and treatment line. In fit older patients, the safety profile seems manageable, with no new safety signals.

Age-related trends in the incidence of metastatic colorectal cancer from 2010 to 2019 in the USA

Aim: To evaluate temporal changes in metastatic colorectal cancer (mCRC), incidence, and use of chemotherapy treatment by age group using real-world data (RWD) from the USA. Methods: A retrospective, observational study describing temporal trends in mCRC incidence and FOLFOXIRI treatment by age group using a nationwide database of commercially and Medicare Advantage-insured patients from 2010 to 2019. Results: Incidence of mCRC increased by 22.1 and 14.9% in the 18-49 and 50-64 years cohorts, respectively, and decreased by 21.6% in the ≥65 years cohort. Overall, younger patients were more likely to receive FOLFOXIRI treatment versus older patients. Conclusion: The shifting age distribution of mCRC should be considered when recommending screening and treatment. Further research is needed to inform age-specific treatment guidelines.

Trends in Colorectal Cancer Mortality in the United States, 1999 - 2020

Background

The United States faces a significant public health issue with colorectal cancer (CRC), which remains the third leading cause of cancer-related fatalities despite early diagnosis and treatment progress.

Methods

This investigation utilized death certificate data from the Centers for Disease Control and Prevention Wide-Ranging OnLine Data for Epidemiologic Research (CDC WONDER) database to investigate trends in CRC mortality and location of death from 1999 to 2020. Additionally, the study utilized the annual percent change (APC) to estimate the average annual rate of change over the specific time period for the given health outcome. Incorporating the location of death in this study served the purpose of identifying patterns related to CRC and offering valuable insights into the specific locations where deaths occurred.

Results

Between 1999 and 2020, there were 1,166,158 CRC-related deaths. The age-adjusted mortality rates (AAMRs) for CRC consistently declined from 20.7 in 1999 to 12.5 in 2020. Men had higher AAMR (18.8) than women (13.4) throughout the study. Black or African American patients had the highest AAMR (21.1), followed by White (15.4), Hispanic/Latino (11.8), American Indian or Alaska native (11.4), and Asian or Pacific Islanders (10.2). The location of death varied, with 41.99% at home, 28.16% in medical facilities, 16.6% in nursing homes/long-term care facilities, 7.43% in hospices, and 5.80% at other/unknown places.

Conclusion

There has been an overall improvement in AAMR among most ethnic groups, but an increase in AAMR has been observed among white individuals below the age of 55. Notably, over one-quarter of CRC-related deaths occur in medical facilities.

Adjuvant chemotherapy non-adherence, patient-centered communication, and patient-level factors in elderly breast and colon cancer patients

BACKGROUND

We examined patient-level factors (patient characteristics, disease and treatment factors, and patient experience), patient-centered communication (PCCM), and non-adherence to adjuvant chemotherapy (AC) guidelines among breast and colon cancer patients to inform AC adherence promotion and improve clinical outcomes.

METHODS

Descriptive statistics for patient-level factors, PCCM, and AC non-adherence (primary non-adherence, non-persistence at 3 and 6 months) were obtained. Multiple logistic regression models were used to estimate AC non-adherence after accounting for the identified patient-level factors.

RESULTS

The majority of the sample (n = 577) were White (87%), breast cancer patients (87%), and reported PCCM (provider communication score ≥ 90%, 73%, provider communication score = 100%, 58%). All three levels of AC nonadherence were significantly higher in breast cancer patients (69%, 81%, and 89% for primary non-adherence, and non-persistence at 3 and 6 months, respectively) than colon cancer patients (43%, 46%, and 62%, respectively). Male sex, survey assistance, and low/average ratings of a personal doctor, specialist, and healthcare were associated with lower PCCM. Older age, breast cancer diagnosis, and diagnosis group following 2007-2009 increased the likelihood of all three levels of AC non-adherence. Comorbidities and PCCM-90 were exclusively associated with non-persistence at 3 months.

CONCLUSIONS

Adjuvant chemotherapy non-adherence varied by cancer diagnosis and treatment factors. The relationship between PCCM and AC non-adherence differed by level of PCCM, time period, and the presence of comorbidities. AC guideline adherence, communication, and value-concordant treatment should be assessed and compared simultaneously to improve our understanding of their interrelationships.

Causes of death among early-onset colorectal cancer population in the United States: a large population-based study

Background

Early-onset colorectal cancer (EOCRC) has an alarmingly increasing trend and arouses increasing attention. Causes of death in EOCRC population remain unclear.

Methods

Data of EOCRC patients (1975-2018) were extracted from the Surveillance, Epidemiology, and End Results database. Distribution of death was calculated, and death risk of each cause was compared with the general population by calculating standard mortality ratios (SMRs) at different follow-up time. Univariate and multivariate Cox regression models were utilized to identify independent prognostic factors for overall survival (OS).

Results

The study included 36,013 patients, among whom 9,998 (27.7%) patients died of colorectal cancer (CRC) and 6,305 (17.5%) patients died of non-CRC causes. CRC death accounted for a high proportion of 74.8%-90.7% death cases within 10 years, while non-CRC death (especially cardiocerebrovascular disease death) was the major cause of death after 10 years. Non-cancer death had the highest SMR in EOCRC population within the first year after cancer diagnosis. Kidney disease [SMR = 2.10; 95% confidence interval (CI), 1.65-2.64] and infection (SMR = 1.92; 95% CI, 1.48-2.46) were two high-risk causes of death. Age at diagnosis, race, sex, year of diagnosis, grade, SEER stage, and surgery were independent prognostic factors for OS.

Conclusion

Most of EOCRC patients died of CRC within 10-year follow-up, while most of patients died of non-CRC causes after 10 years. Within the first year after cancer diagnosis, patients had high non-CRC death risk compared to the general population. Our findings help to guide risk monitoring and management for US EOCRC patients.

Colorectal cancer statistics, 2023

Colorectal cancer (CRC) is the second most common cause of cancer death in the United States. Every 3 years, the American Cancer Society provides an update of CRC statistics based on incidence from population-based cancer registries and mortality from the National Center for Health Statistics. In 2023, approximately 153,020 individuals will be diagnosed with CRC and 52,550 will die from the disease, including 19,550 cases and 3750 deaths in individuals younger than 50 years. The decline in CRC incidence slowed from 3%-4% annually during the 2000s to 1% annually during 2011-2019, driven partly by an increase in individuals younger than 55 years of 1%-2% annually since the mid-1990s. Consequently, the proportion of cases among those younger than 55 years increased from 11% in 1995 to 20% in 2019. Incidence since circa 2010 increased in those younger than 65 years for regional-stage disease by about 2%-3% annually and for distant-stage disease by 0.5%-3% annually, reversing the overall shift to earlier stage diagnosis that occurred during 1995 through 2005. For example, 60% of all new cases were advanced in 2019 versus 52% in the mid-2000s and 57% in 1995, before widespread screening. There is also a shift to left-sided tumors, with the proportion of rectal cancer increasing from 27% in 1995 to 31% in 2019. CRC mortality declined by 2% annually from 2011-2020 overall but increased by 0.5%-3% annually in individuals younger than 50 years and in Native Americans younger than 65 years. In summary, despite continued overall declines, CRC is rapidly shifting to diagnosis at a younger age, at a more advanced stage, and in the left colon/rectum. Progress against CRC could be accelerated by uncovering the etiology of rising incidence in generations born since 1950 and increasing access to high-quality screening and treatment among all populations, especially Native Americans.

Efficacy of adoptively transferred allogeneic CIK cells on colorectal cancer: Augmentative antitumoral effects of GvHD

OBJECTIVE

A preclinical study was designed to evaluate the effects of adoptively transferred cytokine-induced killer (CIK) cells on colorectal adenocarcinoma.

METHODS

Forty NOG mice bearing HT-29 xenograft tumors were developed and equally divided into 2 groups of treatment and control. The mice in the treatment group received cumulatively 40-60 × 10⁶ CIK cells in four divided doses.

RESULTS

Median tumor doubling times for HT-29 xenograft tumors in the treatment and control groups were found to be 8.98 and 4.32 days; respectively. The treatment resulted in tumor growth delay (TGD) of 52.5 %. CIK cell-induced log cell kill (LCK) was found to be 0.67, which implies reduction of 78.6 % of neoplastic colorectal cells. Median length of survival in the treated mice was significantly longer than controls (57 (41-63) vs 41 (31-57) days, P < 0.001). Mice in the treatment group experienced graft-versus-host disease (GvHD) from median of day 13th after the cell therapy. LCK and TGD significantly increased after emergence of GvHD. After necropsy, tumors of the treatment group contained high levels of human-originated CD3⁺, CD4⁺ and CD8⁺ cells and showed significantly lower mitotic counts (P < 0.001) and residual tumor scores (P = 0.005) than the controls (entirely negative for the mentioned CD markers). Ninety percent of the treated mice were found to be responding.

CONCLUSIONS

Adoptive transfer of allogeneic CIK cells may be an efficient antitumoral therapy for colorectal cancer. Allogeneic CIK cell-mediated GvHD may contribute to amplification of graft-versus-tumor effects of the cellular therapy.

Effects of metastatic CRC predictors on treatment outcomes

BACKGROUND

Colorectal cancer (CRC) is the third most commonly diagnosed malignant tumor. The problem of mCRC is urgent due to both an increase in the number of metastatic tumors and the implementation of high-tech treatment methods that have significantly improved the results of a 5-year survival.

METHODS

The research used the method of experiment and observation. Current study included data of 332 patients with CRC who received comprehensive treatment from 2014 to 2018 in oncology centers of the Republic of Kazakhstan. The patients were treated according to the clinical protocols for the treatment of oncological diseases approved in the Republic of Kazakhstan, including surgical treatment, as well as chemotherapy and radiation therapy, depending on the stage and localization of the process. A comprehensive treatment also included surgical treatment, chemotherapy, targeted chemotherapy and, in some cases, radiation therapy for rectal cancer. The diagnosis was confirmed morphologically in all patients; process dissemination was recorded using standard examination methods. Among the patients, women prevailed - 182 (54.8%) women and 150 men (45.2%) were included; the Caucasian race prevailed - 170 (51.2%) patients and 162 (48.8%) patients were of the Asian race. The mean age of the patients at the time of treatment was 56.4 ± 0.6 years (from 25 to 79 years). Histologically, adenocarcinoma prevailed represented by glandular - in 95.6%, mucous - in 2.9% and trabecular - in 1.5% of cases. A comprehensive treatment was used in 209 (63.0%) patients and other types of treatment were used in 123 (37.0%) patients (PCT, stoma + PCT). Radiation therapy was administered to 13 (3.9%) patients diagnosed with rectal cancer.

RESULTS

A comparative analysis of the results of pharmacotherapy in the patients with mCRC showed that of 332 patients, 263 (79.2%) received targeted chemotherapy and 69 (20.8%) received standard polychemotherapy. At the time of the study, 85 (32.3%) patients in the targeted chemotherapy group were still alive, with a median survival of 42.0 ± 1.7 months, 95% CI (38.6-45.4). In the polychemotherapy group, 7 (10.1%) patients were alive, while the median survival rate was 20.0 ± 1.7 months, 95% CI (16.6-23.4).

CONCLUSION

Based on the results, it was concluded that targeted chemotherapy schemes increased progression-free survival, compared to standard polychemotherapy schemes.

Treatment Costs of Colorectal Cancer by Sex and Age: Population-Based Study on Health Insurance Data from Germany

Objective: Evidence on the cost-effectiveness of screening for colorectal cancer (CRC) in the German general population remains scarce as key input parameters, the costs to treat CRC, are largely unknown. Here, we provide detailed estimates on CRC treatment costs over time. Methods: Using insurance claims data from the Vilua healthcare research database, we included subjects with newly diagnosed CRC and subjects who died of CRC between 2012 and 2016. We assessed annualized CRC-related inpatient, outpatient and medication costs for up to five years after first diagnosis and prior to death, stratified by sex and age. Findings: We identified 1748 and 1117 subjects with follow-up data for at least 1 year after diagnosis and prior to death, respectively. In those newly diagnosed, average costs were highest in the first year after diagnosis (men, EUR 16,375−16,450; women, EUR 10,071−13,250) and dropped steeply in the following years, with no consistent pattern of differences with respect to age. Costs prior to death were substantially higher as compared to the initial phase of care and consistently on a high level even several years before death, peaking in the final year of life, with strong differences by sex and age (men vs. women, <70 years, EUR 34,351 vs. EUR 31,417; ≥70 years, EUR 14,463 vs. EUR 9930). Conclusion: Once clinically manifest, CRC causes substantial treatment costs over time, particularly in the palliative care setting. Strong differences in treatment costs by sex and age warrant further investigation.

Association Mining Identifies MAL2 as a Novel Tumor Suppressor in Colorectal Cancer

Introduction

Colorectal cancer (CRC) is a leading cause of cancer-related deaths worldwide. However, the driver genes that promote CRC metastasis remain poorly understood. Association mining mines and extracts the repeated correlations and relevance in a dataset to predict the appearance of other data items according to the appearance of one item.

Methods

Here, the Apriori algorithm was used to find the frequent mutational gene sets (FMGSs) and hidden association rules (ARs) within these FMGSs from 383 CRCs with whole exome sequencing datasets. The weighted correlation network analysis (WGCNA) was used to identify the hub genes in CRC. CCK8, colony formation, cell migration and invasion assays were adopted to detect the roles of hub genes in CRC.

Results

Intriguingly, we found that MAL2 (myelin and lymphocyte protein 2) was associated with TP53 and APC in stage IV of CRC, and further subnetwork exploration based on WGCNA identified MAL2 as a potent hub gene. To validate the metastasis-related role of MAL2 in CRC, a lentivirus-based overexpression system was utilized to construct MAL2-overexpressing human CRC LOVO cells. Overexpression of MAL2 remarkably inhibited CRC cell proliferation and invasion.

Conclusion

Our results highlighted that MAL2 acts as a tumor suppressor in CRC and could serve as a potential therapeutic target.

Multimetric feature selection for analyzing multicategory outcomes of colorectal cancer: random forest and multinomial logistic regression models

Colorectal cancer (CRC) is one of the most common cancers worldwide, and a leading cause of cancer deaths. Better classifying multicategory outcomes of CRC with clinical and omic data may help adjust treatment regimens based on individual's risk. Here, we selected the features that were useful for classifying four-category survival outcome of CRC using the clinical and transcriptomic data, or clinical, transcriptomic, microsatellite instability and selected oncogenic-driver data (all data) of TCGA. We also optimized multimetric feature selection to develop the best multinomial logistic regression (MLR) and random forest (RF) models that had the highest accuracy, precision, recall and F1 score, respectively. We identified 2073 differentially expressed genes of the TCGA RNASeq dataset. MLR overall outperformed RF in the multimetric feature selection. In both RF and MLR models, precision, recall and F1 score increased as the feature number increased and peaked at the feature number of 600-1000, while the models' accuracy remained stable. The best model was the MLR one with 825 features based on sum of squared coefficients using all data, and attained the best accuracy of 0.855, F1 of 0.738 and precision of 0.832, which were higher than those using clinical and transcriptomic data. The top-ranked features in the MLR model of the best performance using clinical and transcriptomic data were different from those using all data. However, pathologic staging, HBS1L, TSPYL4, and TP53TG3B were the overlapping top-20 ranked features in the best models using clinical and transcriptomic, or all data. Thus, we developed a multimetric feature-selection based MLR model that outperformed RF models in classifying four-category outcome of CRC patients. Interestingly, adding microsatellite instability and oncogenic-driver data to clinical and transcriptomic data improved models' performances. Precision and recall of tuned algorithms may change significantly as the feature number changes, but accuracy appears not sensitive to these changes.

Trends in Staging, Treatment, and Survival in Colorectal Cancer Between 1990 and 2014 in the Rotterdam Study

Background

This study aims to assess trends in patient-related factors and treatment strategies in Dutch colorectal cancer (CRC) patients and their effect on survival.

Methods

Data were obtained from the Rotterdam study, an ongoing population-based study of individuals aged ≥45 years. Between 1990 and 2014, incident, pathology-confirmed CRC cases were divided into two groups based on date of diagnosis (either before or after January 1, 2003). Patient characteristics, initial treatment, and date of mortality were collected. Analyses were performed using Kaplan–Meier and Cox proportional hazard models.

Results

Of 14,928 individuals, 272 developed colon cancer and 124 rectal cancer. Median follow-up was 13.2 years. Patients diagnosed after January 1, 2003 were treated chemotherapeutically more often than those diagnosed prior to this date in colon cancer (28.6% vs. 9.1%, p = 0.02) and treated more often with chemotherapy (38.6% vs. 12.3%, p = 0.02) and radiotherapy (41.3% vs. 10.2%, p = 0.001) in rectal cancer. Overall survival, adjusted for patient, tumor characteristics, and treatment, improved in rectal cancer (HR, 0.31; 95% CI, 0.13–0.74) but remained stable in colon cancer (HR, 1.28; 95% CI, 0.84–1.95).

Conclusion

Chemotherapeutic agents and radiotherapy are increasingly used in CRC patients. Survival in rectal cancer improved, whereas in colon cancer this was not observed.

Targeting Colorectal Cancer Cells with a Functionalised Calix[4]arene Receptor: Biophysical Studies

Colorectal cancer (CRC) is a disease which is causing a high degree of mortality around the world. The present study reports the antiproliferative impact of the thioacetamide calix[4]arene, CAII receptor on a highly differentiated Caco-2 cell line. This statement is corroborated by the MTT assay results which revealed a reduction in the cell viability with an IC50 value of 19.02 ± 0.04 µM. Microscopic results indicated that at the starting amount of 10 µM of CAII, a decrease in cells confluency can already be observed in addition to changes in cells morphology. Cell metabolic pathway changes were also investigated. 1H NMR findings showed downregulation in lactate, pyruvate, phosphocholine, lipids, and hydroxybutyrate with the upregulation of succinate, indicating a decline in the cells proliferation. Some biochemical alterations in the cells as a result of the CAII treatment were found by Raman spectroscopy.

Nano-Delivery of a Novel Inhibitor of Polynucleotide Kinase/Phosphatase (PNKP) for Targeted Sensitization of Colorectal Cancer to Radiation-Induced DNA Damage

Inhibition of the DNA repair enzyme polynucleotide kinase/phosphatase (PNKP) increases the sensitivity of cancer cells to DNA damage by ionizing radiation (IR). We have developed a novel inhibitor of PNKP, i.e., A83B4C63, as a potential radio-sensitizer for the treatment of solid tumors. Systemic delivery of A83B4C63, however, may sensitize both cancer and normal cells to DNA damaging therapeutics. Preferential delivery of A83B4C63 to solid tumors by nanoparticles (NP) was proposed to reduce potential side effects of this PNKP inhibitor to normal tissue, particularly when combined with DNA damaging therapies. Here, we investigated the radio-sensitizing activity of A83B4C63 encapsulated in NPs (NP/A83) based on methoxy poly(ethylene oxide)-b-poly(α-benzyl carboxylate-ε-caprolactone) (mPEO-b-PBCL) or solubilized with the aid of Cremophor EL: Ethanol (CE/A83) in human HCT116 colorectal cancer (CRC) models. Levels of γ-H2AX were measured and the biodistribution of CE/A83 and NP/A83 administered intravenously was determined in subcutaneous HCT116 CRC xenografts. The radio-sensitization effect of A83B4C63 was measured following fractionated tumor irradiation using an image-guided Small Animal Radiation Research Platform (SARRP), with 24 h pre-administration of CE/A83 and NP/A83 to Luc⁺/HCT116 bearing mice. Therapeutic effects were analyzed by monitoring tumor growth and functional imaging using Positron Emission Tomography (PET) and [¹⁸F]-fluoro-3’-deoxy-3’-L:-fluorothymidine ([¹⁸F]FLT) as a radiotracer for cell proliferation. The results showed an increased persistence of DNA damage in cells treated with a combination of CE/A83 or NP/A83 and IR compared to those only exposed to IR. Significantly higher tumor growth delay in mice treated with a combination of IR and NP/A83 than those treated with IR plus CE/A83 was observed. [¹⁸F]FLT PET displayed significant functional changes for tumor proliferation for the drug-loaded NP. This observation was attributed to the higher A83B4C63 levels in the tumors for NP/A83-treated mice compared to those treated with CE/A83. Overall, the results demonstrated a potential for A83B4C63-loaded NP as a novel radio-sensitizer for the treatment of CRC.

Economic Evaluation of Monoclonal Antibodies in Metastatic Colorectal Cancer: A Systematic Review

INTRODUCTION

Colorectal cancer (CRC) is one of the major causes of mortality and morbidity worldwide. The median overall survival (OS) of patients with metastatic CRC (mCRC) has doubled over the last 20 years partly due to the introduction of advanced biologic therapies. However, these treatment modalities bear significant costs on healthcare systems globally, and may jeopardize their fiscal sustainability. The aim of this systematic review was to critically appraise the economic evaluations of monoclonal antibodies in mCRC.

METHODOLOGY

A literature search was performed in the electronic databases of: Cochrane Central Register of Controlled Trials, Cochrane Database of Systematic Reviews, Database of Abstracts of Reviews of Effects, EMBASE, EMBASE Alert, PUBMED, NHS Economic Evaluation and Health Technology Assessment Database for full articles published from 1 January 2013 to 31 December 2020.

RESULTS

Twenty economic analyses were identified in the literature that fulfilled the inclusion criteria and evaluated the cost-effectiveness of (a) bevacizumab as first-line treatment for mCRC and as maintenance treatment, (b) cetuximab as first-line treatment, (c) panitumumab versus bevacizumab and cetuximab versus bevacizumab as first-line treatment, (d) aflibercept and ramucirumab as second-line treatment, (e) cetuximab and panitumumab as third-line treatment, (f) cetuximab versus panitumumab as later lines of treatment, and (g) RAS testing prior to anti-epidermal growth factor receptor (EGFR) treatment.

CONCLUSIONS

Bevacizumab in combination with chemotherapy is cost-effective as neither first-line treatment nor maintenance treatment. Sequential treatment with bevacizumab in first-line and second-line treatment was also not cost-effective. Testing for KRAS and extended RAS mutations is cost-effective and should be performed prior to anti-EGFR treatment. In the RAS wild-type subgroup of mCRCs the use of anti-EGFR (panitumumab or cetuximab) in first-line treatment leads to a more favorable cost-effectiveness profile than the corresponding anti-VEGF (bevacizumab). Cetuximab is not cost-effective as a first-line treatment. Anti-EGFR administration is not a cost-effective strategy in third-line treatment, even for RAS wild-type mCRCs, compared to best supportive care. Aflibercept was superior to ramucirumab and costed less, but neither were cost-effective compared to standard care.

Annual Report to the Nation on the Status of Cancer, Part 2: Patient Economic Burden Associated With Cancer Care

BACKGROUND

The American Cancer Society, National Cancer Institute, Centers for Disease Control and Prevention, and North American Association of Central Cancer Registries provide annual information about cancer occurrence and trends in the United States. Part 1 of this annual report focuses on national cancer statistics. This study is part 2, which quantifies patient economic burden associated with cancer care.

METHODS

We used complementary data sources, linked Surveillance, Epidemiology, and End Results-Medicare, and the Medical Expenditure Panel Survey to develop comprehensive estimates of patient economic burden, including out-of-pocket and patient time costs, associated with cancer care. The 2000-2013 Surveillance, Epidemiology, and End Results-Medicare data were used to estimate net patient out-of-pocket costs among adults aged 65 years and older for the initial, continuing, and end-of-life phases of care for all cancer sites combined and separately for the 21 most common cancer sites. The 2008-2017 Medical Expenditure Panel Survey data were used to calculate out-of-pocket costs and time costs associated with cancer among adults aged 18-64 years and 65 years and older.

RESULTS

Across all cancer sites, annualized net out-of-pocket costs for medical services and prescriptions drugs covered through a pharmacy benefit among adults aged 65 years and older were highest in the initial ($2200 and $243, respectively) and end-of-life phases ($3823 and $448, respectively) and lowest in the continuing phase ($466 and $127, respectively), with substantial variation by cancer site. Out-of-pocket costs were generally higher for patients diagnosed with later-stage disease. Net annual time costs associated with cancer were $304.3 (95% confidence interval = $257.9 to $350.9) and $279.1 (95% confidence interval = $215.1 to $343.3) for adults aged 18-64 years and ≥65 years, respectively, with higher time costs among more recently diagnosed survivors. National patient economic burden, including out-of-pocket and time costs, associated with cancer care was projected to be $21.1 billion in 2019.

CONCLUSIONS

This comprehensive study found that the patient economic burden associated with cancer care is substantial in the United States at the national and patient levels.

Abnormal Dihydropyrimidine Dehydrogenase Activity as an Indicator of Potential 5-Fluorouracil Linked Cardiotoxicity in Colorectal Cancer Patients: Are Toxic Events Inevitable?

Colorectal cancer (CRC) treatment can be limited to surgical resection for low stages of the disease while subsequent chemotherapy is the preferred treatment for the higher-stage disease. This chemotherapy relies heavily on fluoropyrimidine: 5-fluorouracil (5-FU) and capecitabine, a role played for decades. Fluoropyrimidine-linked treatment can present important and even lethal toxic events at the cardiac level like acute coronary syndrome, arrhythmias, and death.

The production of these toxic events depends on the capacity of a subject to metabolize the fluoropyrimidines adequately, and this depends on the activity of the enzyme dihydropyrimidine dehydrogenase (DPD). Any change that affects the quantity or quality of this enzyme will compromise its capacity to metabolize the fluoropyrimidines. The resultant abnormal enzyme activity exposes the patient to continuously high levels of the chemotherapeutic agent or its catabolites. Consequently, the patient becomes more susceptible to pyrimidine-linked toxic adverse events.

Genetic testing of patients for potential decreased DPD activity before subjecting them to fluoropyrimidine-based chemotherapy will help identify subjects at greater risk of increased cardiotoxicities, the possibility of prompt intervention, should these appear, and a multidisciplinary strategy aimed at managing these cases. Potential cases of cardiotoxicity in CRC patients, candidates to fluoropyrimidine toxicities, can be anticipated by pretreatment screening of DPD activity. Pretreatment screening will reduce many hospitalizations with a consequent decrease in costs both to the patients and the healthcare system.

This review article will examine the 5-FU linked cardiotoxicity, known correlated risk factors, clinical manifestations, management strategy, and the role of genetic testing in identifying high-risk patients.

Multifactorial causation of early onset colorectal cancer

The multiple-hit hypothesis of cancer, including colorectal cancer (CRC), states that neoplastic development requires a sequence of mutations and epigenetic changes in driver genes. We have previously proposed that obesity increases CRC risk by supporting neoplastic development through adipokine-induced signaling, and this proliferative signaling substitutes for specific driver gene mutations. In support of this hypothesis, analyses of The Cancer Genome Atlas (TCGA) mutation data have revealed that obese patients with microsatellite stable CRC exhibit fewer driver gene mutations than CRC patients with normal body mass index. The lower number of driver gene mutations required for cancer development may shorten the neoplastic process and lead to an early onset of CRC. Therefore, obesity could be one factor explaining the rise of CRC incidence among younger individuals (< 50 years of age); furthermore, early onset CRC has been associated with the increasing incidence of metabolic syndrome and obesity in this age group. However, CRC incidence among older individuals (> 50 years of age) is stable or declining, despite the high rates of metabolic syndrome and obesity in this age group. In search for explanations of this phenomenon, we discuss several factors that may contribute to the divergent CRC incidence trends in populations under, and above, the age of 50, despite the rising levels of metabolic syndrome and obesity across all ages. First, older individuals with metabolic dysregulation are more frequently on maintenance medications, such as aspirin, β-blockers, lipid-lowering drugs, ACE inhibitors, metformin, etc., compared to younger individuals. Such treatments may suppress specific adipokine-induced proliferative signaling pathways, and therefore counteract and slow down neoplastic development in medicated overweight/obese individuals. Second, in the past decades, the incidence of infectious diseases accompanied by febrile episodes has been decreasing and the use of antipyretics increasing. Compared to normal cells, neoplastic cells are more sensitive to high body temperature; therefore, the decreased number of febrile episodes in childhood and adolescence may contribute to increased cancer incidence before the age of 50. Third, obesity at younger age may expand the stem cell compartment. An increased number of intestinal stem cells and stem cell divisions translates into a higher probability of sporadic mutations in the stem cells, and therefore, a greater chance of neoplasia. In conclusion, we hypothesize that early onset CRC has multifactorial causation and the proposed associations could be examined through analyses of existing data.

Colorectal cancer adjuvant chemotherapy trends among a nonelderly veteran cohort at a southern veterans health administration

Background

For patients with high‐risk stage II or stage III colorectal cancer (CRC), adjuvant chemotherapy (AC) improves survival, yet use varies substantially across medical oncology settings.

Aim

Utilization of guideline concordant CRC AC was assessed at a Veterans Health Administration (VHA) facility to determine quality improvement initiatives.

Methods and Results

The study was a retrospective review of CRC surgeries from January 1, 2000 to December 31, 2015 at a South Regional VHA. Inclusion criteria consisted of pathologic high‐risk stage II or stage III CRC, with exclusion for age ≥80, age ≥75 hospitalized with major co‐morbidity in the prior year, and death or discharge to hospice within 30 days of the index surgery. The primary predictor was year‐group; partitioned 2000–2005, 2006–2010, 2011–2015 to account for changes in NCCN high risk stage II definitions. Primary outcome was AC receipt. Secondary outcome was reason for chemotherapy omission. Among 180 eligible surgeries (121 colon and 59 rectal cancers), patients were mostly male (96%), white (79%) and with median age 64 years. Overall, 117 (65%) received AC. Compared to 2000–2005, patients undergoing surgery between 2011 and 2015 were less likely to receive AC (odds ratio 0.35; 95% confidence interval [CI] 0.14–0.82), due to more patients declining AC (27% vs. 6%, p < .01) in the NCCN eligible cohort (N = 180), and (32% vs. 8%, p < .01) in an analysis of patients who completed appointments and had AC recommended by providers (N = 146).

Conclusions

Survival benefitting AC decreased over time among a nonelderly Veteran cohort eligible for AC. Evaluating care decisions and trends within other VHA facilities and outside the VHA are warranted.

Survival of patients newly diagnosed with colorectal cancer and with a history of previous cancer

Patients with previous cancer are often excluded from clinical trials despite limited evidence about their prognosis. We examined the effect of previous cancer on overall and colorectal cancer (CRC)-specific survival of patients newly diagnosed with CRC. This population-based cohort study from the U.S.A. included patients aged ≥66 years and diagnosed with CRC between 2005 and 2015 in linked Surveillance, Epidemiology, and End Results-Medicare data. We estimated the stage-specific effects of a previous cancer on overall survival using Cox regression and on CRC-specific survival using competing risk regression. We also examined the effect of previous cancer type, timing, and stage on overall survival. Of 112,769 patients, 14.1% were previously diagnosed with another cancer--commonly prostate (32.9%) or breast (19.4%) cancer, with many (47.1%) diagnosed <5 years of CRC. For all CRC stages except IV, in which there was no difference, patients with previous cancer (vs. without) had worse overall survival. However, patients with previous cancer had improved CRC-specific survival. Overall survival for those with stage 0-III CRC varied by previous cancer type, timing, and stage; for example, patients with previous melanoma had overall survival equivalent to those with no previous cancer. Our results indicate that, in general, CRC patients with previous cancer have worse overall survival but superior CRC-specific survival. Given their equivalent survival to those without previous cancer, patients with previous melanoma and those with stage IV CRC with any type of previous cancer should be eligible to participate in clinical trials.

Assessment of Imaging Protocol and Patients Radiation Exposure in Computed Tomography Colonography

In the screening and identifying of colon and rectum malignancy, computed tomography colonography (CTC) is a highly effective imaging technique, albeit patients receiving a significant effective dose. Accordingly, patient dose evaluation is an important need, seeking to ensure benefits outweigh the projected cancer risk. Objective: For CTC procedures carried out in the Radiology Department, Medical Imaging Operation Services, King Fahad Medical City (KFMC), evaluation is done using the current American College of Radiology (ACR) imaging protocol and concomitant patient-effective doses. Study is carried out on a sample size of 55 CTC procedures, involving 25 males (45%) and 30 females (55%). The patients were classified as follows: two groups based on CT machine; four groups based on the applied protocol; and three groups based on the procedure results. All procedures were carried out using two machines, the products of two different vendors (a GE Healthcare DISCOVERY CT 750 HD 64 slices dual-energy scanner and a Philips Brilliance CT 64 slices scanner). The overall mean, standard deviation (SD), median, and range of the effective dose (in mSv) were 11.57 ± 7.75, 9.25 (2.17–31.93). Automatic tube current modulation (ATCM) shows a significant increase in CTDIvol up to 69% and effective dose (mSv) up to 95% than the manual tube current (mA) compared to the standard protocol. The CT protocol variation results in a three-fold variation in patient-effective dose. The technologist role is crucial in selecting a noise reference based on patient weight and adjusting tube current per slice to avoid overexposure during ATCM protocol.

Early colorectal cancer detection-Current and evolving challenges in evidence, guidelines, policy, and practices

The understanding at the beginning of the last century that colorectal cancer began as a localized disease that progressed and became systemic, and that most colorectal cancer arose from adenomatous polyps gave rise to aggressive attempts at curative treatment and eventually attempts to detect advanced lesions before they progressed to invasive disease. In the last four decades, steadily greater uptake of screening has led to reductions in colorectal cancer incidence and mortality. However, the fullest potential of screening is not being met due to the lack of organized screening, where a systems approach could lead to higher rates of screening of average and high risk groups, higher quality screening, and prompt followup of adults with positive screening tests. ABSTRACT: Since the beginning of the 20th century, there has been a general understanding that colorectal cancer is a clonal disease that progresses from a localized stage with a favorable prognosis through progressively more advanced stages which have progressively worse prognosis. That understanding led first to determined efforts to detect and treat early stage symptomatic disease, and then to detect pre-symptomatic colorectal cancer and precursor lesions, where there was hope that the natural history of the disease could be arrested and the incidence and premature mortality of colorectal cancer averted. Toward the end of the last century, guidelines for colorectal cancer screening, growth in the number of technical options for screening, and a steady increase in the proportion of the adult population who attended screening contributed to the beginning of a significant decline in colorectal cancer incidence and mortality. Despite this progress, colorectal cancer remains the third leading cause of death among men and women in the United States. Screening for early detection of precursor lesions and localized cancer offers the single most productive opportunity to further reduce the burden of disease, and yet nearly four in five deaths from colorectal cancer are associated with having never been screened, not recently screened, or not followed up for an abnormal screening test. This simple observation is a call to action in all communities to apply existing knowledge to fulfill the potential to prevent avertable incidence and mortality.

Participatory simulation modeling to inform colorectal cancer screening in a complex remote northern health system: Canada's Northwest Territories

BACKGROUND & AIMS

Colorectal cancer (CRC) mortality in the Northwest Territories (NWT), a northern region of Canada, could be reduced by implementing a CRC screening program. However, this may require additional colonoscopy resources. We used participatory simulation modeling to predict colonoscopy demand and to develop strategies for implementing a feasible and effective CRC screening program in this complex remote northern health system.

METHODS

Using a participatory simulation modeling approach, we first developed a conceptual model of CRC screening with local collaborators. This approach informed our parameter adjustments of an existing microsimulation model, OncoSim-CRC, using data from a retrospective cohort review of CRC screening between 2014-2019 and secondary data. Model scenarios reflecting program implementation were run for 500 million cases. Validity was assessed, and outputs analyzed with collaborators. Alternative scenarios were developed to reduce colonoscopy demand and results were presented to end-users.

RESULTS

We estimated that colonoscopy demand with a CRC screening program phased-in over 5 years would surpass capacity within 2 years. If demand is met, screen-detected cancers would increase by 110 %, and clinically-detected cases would reduce by 26 % over the next 30 years. We also found that prolonging the phase-in period, or revising adenoma follow-up guidelines would reduce colonoscopy demand while still improving cancer detection. Both strategies were considered feasible by collaborators. The adjusted model was valid, and the projections informed local end-users plans for CRC screening delivery.

CONCLUSIONS

Using participatory simulation modeling, we projected that a screening program would improve CRC detection but surpass current colonoscopy capacity. Phasing-in the screening program and reducing endoscopic adenoma follow-up would enhance feasibility of a CRC screening program in the NWT and help maintain its effectiveness.

Survival in stage IIB/C compared to stage IIIA rectal cancer: an Australian experience affirming that size does matter

BACKGROUND

Colorectal cancer (CRC) is one of the most commonly diagnosed malignancies globally; however, a survival paradox has been observed unique to this malignancy. The aim of this study was to review survival outcomes of patients diagnosed with stage II and stage III rectal cancer, to determine whether a survival paradox is present in our centre and assess for patient-related factors that can explain the observed paradox or were predictors of prognosis.

METHODS

A retrospective review of data collected from 2006 to 2018 of patients diagnosed with rectal cancer in three separate centres was conducted. Percentages pertaining to patient and tumour characteristics, presentation, management and subsequent recurrence were reported. Preoperative and postoperative factors associated with survival were determined using univariable and multivariable logistic regression analysis.

RESULTS

Stage IIB/C patients had significantly higher carcinoembryonic antigen (CEA) levels compared to stage IIA and stage IIIA patients (P < 0.001). Stage IIB/C patients had significantly larger primary rectal tumour and were more symptomatic (i.e. rectal bleeding, altered bowel habits and obstruction) at the time of diagnosis (P = 0.007). Preoperative CEA was an independent prognostic factor for cancer-specific survival in patients diagnosed with stage IIB/C and stage IIIA disease (P = 0.008) on multivariable analysis. Overall survival was greatest in stage IIIA disease, which was significantly greater than stage IIB/C disease.

CONCLUSION

This study confirms the existence of a survival paradox in patients diagnosed with CRC in an Australian tertiary centre and adds further weight to the revision of the TNM staging to provide more emphasis on the T stage.

The association of comorbidities with administration of adjuvant chemotherapy in stage III colon cancer patients: a systematic review and meta-analysis

Background:

Chemotherapy is an established treatment for stage III colon cancer cases. Older age is known to be associated with less chemotherapy use in these patients, but there might be other relevant factors besides age that influence treatment administration. We summarized evidence on associations between comorbidity and adjuvant chemotherapy administration in stage III colon cancer patients in a systematic review and meta-analysis.

Methods:

We searched the PubMed and Web of Science databases up to 2 June 2020 for studies on comorbidities and chemotherapy use in patients with stage III colon cancer. Summary odds ratios (OR) and 95% confidence intervals (95% CI) were estimated using random-effects models. Subgroup analyses according to year of colon cancer diagnosis, timing of comorbidity assessment, and geographical region were also conducted.

Results:

Thirty-three studies were included in this review, including 219,406 stage III colon cancer patients overall. Chemotherapy administration was 60.9% (95% CI: 56.9% to 64.9%), increasing from 57.1% before 2001 to 66.3% after 2010. There were inverse associations between comorbidities and chemotherapy administration. Compared with patients with Charlson comorbidity score 0, those with scores 1 (OR = 0.79, 95% CI = 0.72–0.87) and 2+ (OR = 0.49, 95% CI = 0.42–0.56) received chemotherapy less often. Among comorbidities, the strongest predictors of chemotherapy non-use were dementia (OR = 0.37, 95% CI = 0.33–0.54), followed by heart failure (OR = 0.44, 95% CI = 0.28–0.70) and stroke (OR = 0.56, 95% CI = 0.38–0.81).

Conclusions:

Merely 60% of stage III colon cancer patients receive chemotherapy. Comorbidities are strong predictors of chemotherapy non-use, but the association differs by comorbid condition and is strongest with dementia. Given the survival disadvantage of colon cancer patients with comorbidities, further evidence on the risk–benefit ratio of chemotherapy according to the type and severity of comorbidity and on the extent to which the survival disadvantage of comorbidity is explained by less use or lower tolerability of chemotherapy is needed to foster personalized medical care in these patients.

Analyzing non-cancer causes of death of colorectal carcinoma patients in the US population for the years 2000-2016

Background

Colorectal cancer (CRC) treatment and patient survival improved greatly. Consequently an increased incidence of non‐cancer‐related deaths is observed. This study analyzed the causes of non‐cancer death for people suffering from CRC based on the year of diagnosis, follow‐up time, and patient's age.

Methods

The data from patients diagnosed with CRC in the years 2000–2016 were taken from the Surveillance, Epidemiology, and End Results 18 database. Patients were categorized according to: death from CRC, non‐CRC cancer, and non‐cancer. Constituent ratios and standardized mortality ratios (SMRs) were calculated to describe the death causes distribution and relative death risks.

Results

Between 2000 and 2016, a stable and rapid drop for the original diagnosis as death cause for CRC patients was observed (70.19% to 49.35%). This was coupled to an increase in non‐cancer‐associated death reasons (23.38% to 40.00%). The most common non‐cancer death cause was heart disease, especially for elderly patients. However, deaths from accidents and adverse effects were frequent in younger CRC patients. Patients died from septicemia more often within the first follow‐up year; however, a 6‐fold increase in death from Alzheimer's disease was found for after at least 180 months follow‐up time.

The SMRs of all 25 non‐cancer death causes initially decreased in all CRC subgroups, followed by an increase with follow‐up times. Gradually decreasing SMR values were observed with increasing age of CRC patients.

Conclusions

These findings could help modify and sharpen preventive measures and clinical management and raise physician's awareness to potential non‐CRC death risk factors for CRC patients.

Estimating Population-Based Recurrence Rates of Colorectal Cancer over Time in the United States

BACKGROUND

Population-based metastatic recurrence rates for patients diagnosed with nonmetastatic colorectal cancer cannot be estimated directly from population-based cancer registries because recurrence information is not reported. We derived population-based colorectal cancer recurrence rates using disease-specific survival data based on our understanding of the colorectal cancer recurrence-death process.

METHODS

We used a statistical continuous-time multistate survival model to derive population-based annual colorectal cancer recurrence rates from 6 months to 10 years after colorectal cancer diagnosis using relative survival data from the Surveillance, Epidemiology, and End Results Program. The model was based on the assumption that, after 6 months of diagnosis, all colorectal cancer-related deaths occur only in patients who experience a metastatic recurrence first, and that the annual colorectal cancer-specific death rate among patients with recurrence was the same as in those diagnosed with de novo metastatic disease. We allowed recurrence rates to vary by post-diagnosis time, age, stage, and location for two diagnostic time periods.

RESULTS

In patients diagnosed in 1975-1984, annual recurrence rates 6 months to 5 years after diagnosis ranged from 0.054 to 0.060 in stage II colon cancer, 0.094 to 0.105 in stage II rectal cancer, and 0.146 to 0.177 in stage III colorectal cancer, depending on age. We found a statistically significant decrease in colorectal cancer recurrence among patients diagnosed in 1994-2003 compared with those diagnosed in 1975-1984 for 6 months to 5 years after diagnosis (hazard ratios between 0.43 and 0.70).

CONCLUSIONS

We derived population-based annual recurrence rates for up to 10 years after diagnosis using relative survival data.

IMPACT

Our estimates can be used in decision-analytic models to facilitate analyses of colorectal cancer interventions that are more generalizable.

Genetic variants in Hippo signalling pathway-related genes affect the risk of colorectal cancer

The Hippo signalling pathway plays a crucial role in carcinogenesis. Therefore, we hypothesized that genetic variants in genes related to this pathway are associated with the colorectal cancer risk. A case-control study including 1150 patients and 1342 controls was performed to assess the association of genetic variants of genes involved in the Hippo signalling pathway with the risk of colorectal cancer. The results were corrected for multiple comparisons using the false discovery rate (FDR). We used a regression model to determine the effects of single-nucleotide polymorphisms (SNPs) on the survival of patients with colorectal cancer in The Cancer Genome Atlas (TCGA) datasets. An expression quantitative trait loci (eQTL) analysis was performed using TCGA datasets and the Genotype-Tissue Expression (GTEx) project. Gene Expression Omnibus (GEO) datasets were used to provide additional data on the expression of genes in colorectal cancer. The SCRIB rs13251492 G allele was associated with a significantly decreased risk of colorectal cancer (odds ratio (OR) = 0.79, 95% confidence interval (CI) = 0.70-0.89, P = 7.76 × 10^-5, P_(FDR) = 6.98 × 10^-4). Patients with the rs13251492 AG/GG allele experienced a longer recurrence-free survival (RFS) time (hazard ratio (HR) = 0.64, 95% CI = 0.42-0.99, P = 0.049) than patients with the rs13251492 A allele. The eQTL analysis revealed a significant association between rs13251492 and the expression of the SCRIB mRNA in colorectal tumors. Dual-luciferase reporter assays in DLD-1 and HCT116 cells revealed a lower enhancer activity of the rs13251492 G allele than the A allele. In addition, the SCRIB mRNA was expressed at markedly higher levels in colorectal cancer tissues than in normal tissues. Therefore, we identified the SCRIB rs13251492 variant as a novel colorectal cancer susceptibility locus and provided evidence of its functional relevance.

Exercise and colorectal cancer: a systematic review and meta-analysis of exercise safety, feasibility and effectiveness

Background

This meta-analysis evaluated the safety, feasibility and effect of exercise among individuals with colorectal cancer.

Methods

A database search (CINAHL, Ebscohost, MEDLINE, Pubmed, ProQuest Health and Medical Complete, ProQuest Nursing, Science Direct) for randomised, controlled, exercise trials involving individuals with colorectal cancer, published before January 1, 2020 was undertaken. Safety (adverse events), feasibility (withdrawal and adherence rates) and effect data (health outcomes including quality of life, QoL) were abstracted. Risk difference (RD) and standardised mean differences (SMD) were calculated to compare safety and effects between exercise and usual care (UC). Subgroup analyses were conducted to assess whether outcomes differed by exercise mode, duration, supervision and treatment. Risk of bias was assessed using the Physiotherapy Evidence Database tool.

Results

For the 19 trials included, there was no difference in adverse event risk between exercise and UC (RD = 0.00; 95% CI:–0.01, 0.01, p = 0.92). Median withdrawal rate was 12% (0–22%) and adherence was 86% (42–91%). Significant effects of exercise compared to UC were observed for QoL, fatigue, aerobic fitness, upper-body strength, depression, sleep and reduced body fat (SMD = 0.21–0.66, p < 0.05). Subgroup analyses suggested larger benefits (p < 0.05) for QoL and fatigue for supervised interventions; for QoL, aerobic fitness and reduced body fat for ≥12-week interventions; and for aerobic fitness when interventions were during chemotherapy.

Conclusion

Although reporting of safety and compliance data was lacking in most trials, findings support that exercise is safe and feasible in colorectal cancer. Further, participation in mixed-mode exercise, including unsupervised exercise, leads to improvements in various health-related outcomes.

Is Primary Tumor Excision and Specific Metastases Sites Resection Associated With Improved Survival in Stage Ⅳ Colorectal Cancer? Results From SEER Database Analysis

OBJECTIVE

We aimed to explore the prognostic value of primary tumor and specific metastases excision on survival among patients with stage IV colorectal cancer (CRC) in the Surveillance, Epidemiology, and End Results (SEER) database.

METHODS

Patients with stage IV CRC were selected using SEER database between 2010 and 2013. Survival rate was calculated according to the Kaplan-Meier method, and differences between curves were tested by the log-rank test. Cox proportional hazards model was used in the multivariable analysis.

RESULTS

Included in this study were 27 878 patients with distant metastatic CRC. Among the single organ site of metastatic CRC, patients with solitary metastasis of lung showed the highest median overall survival (OS). Both primary and metastatic sites surgical resection for patients with liver, lung, and simultaneous liver and lung metastases had better median OS. Age younger than 65 years, Asian and Pacific Islander, distal colon and rectum, and palliative primary tumor and metastatic lesions resection were associated with better OS after multivariate analysis. Palliative primary tumor and metastatic lesions resection had a significant survival benefit compared with nonsurgical group in selected patients.

CONCLUSION

These findings support the use of preemptive surgery in the management of highly selected metastatic CRC patients.

Colorectal cancer statistics, 2020

Colorectal cancer (CRC) is the second most common cause of cancer death in the United States. Every 3 years, the American Cancer Society provides an update of CRC occurrence based on incidence data (available through 2016) from population-based cancer registries and mortality data (through 2017) from the National Center for Health Statistics. In 2020, approximately 147,950 individuals will be diagnosed with CRC and 53,200 will die from the disease, including 17,930 cases and 3,640 deaths in individuals aged younger than 50 years. The incidence rate during 2012 through 2016 ranged from 30 (per 100,000 persons) in Asian/Pacific Islanders to 45.7 in blacks and 89 in Alaska Natives. Rapid declines in incidence among screening-aged individuals during the 2000s continued during 2011 through 2016 in those aged 65 years and older (by 3.3% annually) but reversed in those aged 50 to 64 years, among whom rates increased by 1% annually. Among individuals aged younger than 50 years, the incidence rate increased by approximately 2% annually for tumors in the proximal and distal colon, as well as the rectum, driven by trends in non-Hispanic whites. CRC death rates during 2008 through 2017 declined by 3% annually in individuals aged 65 years and older and by 0.6% annually in individuals aged 50 to 64 years while increasing by 1.3% annually in those aged younger than 50 years. Mortality declines among individuals aged 50 years and older were steepest among blacks, who also had the only decreasing trend among those aged younger than 50 years, and excluded American Indians/Alaska Natives, among whom rates remained stable. Progress against CRC can be accelerated by increasing access to guideline-recommended screening and high-quality treatment, particularly among Alaska Natives, and elucidating causes for rising incidence in young and middle-aged adults.

Sturgeon (Acipenser)-Derived Chondroitin Sulfate Suppresses Human Colon Cancer HCT-116 Both In Vitro and In Vivo by Inhibiting Proliferation and Inducing Apoptosis

Chondroitin sulfate (CS), mainly present in the cartilage and bone of animals, is known as a potential food-derived bioactive that has several biological functions, such as anti-arthritic and anti-inflammatory activity. Sturgeon (Acipenser), an important fishery resource in China, contains an abundance of CS in their cartilage. In our previous study, we have extracted and purified CS from sturgeon cartilage. Herein, we further investigate the health benefits of sturgeon-derived chondroitin sulfate (SCS), especially for colorectal cancer treatment. The in vitro study indicated that SCS could inhibit the proliferation of the human colon cancer cell line HCT-116 in a dose-dependent manner, which was associated with cell cycle arrest. In addition, SCS also led to extensive cellular apoptosis in colon cancer cell HCT-116 cells. Meanwhile, an in vivo study showed that SCS treatment significantly inhibited the tumor development of xenograft HCT-116 in mice via proliferation suppression and apoptosis induction. Further, a mechanistic study demonstrated that the apoptosis induction was mainly due to the activation of the Bcl-2 family-associated mitochondrial pathway. Overall, our results provided a basis for SCS as a promising agent against colon cancer.

Epidemiology and Mechanisms of the Increasing Incidence of Colon and Rectal Cancers in Young Adults

In contrast to the decreasing incidence of colorectal cancer (CRC) in older populations, the incidence has nearly doubled in younger adults since the early 1990s. Approximately 1 in 10 new diagnoses of CRC are now made in individuals 50 years or younger. Patients' risk of CRC has been calculated largely by age and family history, yet 3 of 4 patients with early-onset CRC have no family history of the disease. Rapidly increasing incidence rates in younger people could result from generational differences in diet, environmental exposures, and lifestyle factors. We review epidemiologic trends in CRC, data on genetic and nongenetic risk factors, and new approaches for determining CRC risk. These may identify individuals likely to benefit from early screening and specialized surveillance.

Cost-effectiveness and budget impact analyses of colorectal cancer screenings in a low- and middle-income country: example from Thailand

Objectives: Colorectal cancer (CRC) screening programs have been reported to be cost-effective in many high-income countries. However, there was no such study in low- and middle-income countries. This study aimed to evaluate cost-effectiveness and budget impact of CRC screening modalities for average-risk persons in Thailand.Methods: A decision tree coupled with a Markov model was used to estimate lifetime costs and health benefits of fecal immunochemical test (FIT) and colonoscopy using a societal perspective. The input parameters were obtained from a CRC screening project at a Thai tertiary care hospital, Thai health care costs and databases, and systematic literature review. Results were reported as incremental cost-effectiveness ratios (ICERs) in 2017 US Dollars (USD) per quality-adjusted life year (QALY) gained. Sensitivity analyses were performed to assess the influence of parameter uncertainty. Finally, budget impact analysis was conducted.Results: At the Thai ceiling threshold of societal willingness-to-pay of 4,706 USD, the screening colonoscopy every 10 years and annual FIT, starting at age 50, was cost-effective, as compared to no screening resulting in 15.09 and 15.00 QALYs with the ICERs of 600.20 and 509.84 USD/QALY gained, respectively. Colonoscopy every 10 years and annual FIT could prevent 17.9% and 5.7% of early stage cancer and 27.8% and 9.2% of late stage cancer per 100,000 screening over lifetime when compared to no screening, respectively. The colonoscopy screening was cost-effective with the ICER of 646.53 USD/QALY gained when compared to FIT. The probabilities of being cost-effective for the colonoscopy and FIT were 75% and 25%, respectively. Budget impact analysis showed the colonoscopy screening required an 8-times higher budget than FIT.Conclusions: Colonoscopy offers the best value for money of CRC screenings in Thailand. Annual FIT is potentially feasible since it requires less resources. Our findings can be used as part of evidence for informing policy decision making.Key points for decision makersThere was a lack of cost-effective study of colorectal cancer screening programs in low- and middle-income countries.This study evaluated lifetime health outcomes and costs, and the cost-effectiveness of colorectal screening options for average-risk persons in Thailand.Colonoscopy screening every 10 years is cost-effective with high probability of being cost-effective as compared with annual fecal immunochemical test.Screening by annual fecal immunochemical test is more feasible in terms of human resource and budgetary burden.Colorectal screening programs provides an opportunity for early diagnosis and treatments to prevent advance colorectal stages and avoid higher consequent costs.This study contributes a new evidence-based knowledge for Thailand and can be used to support policy decision making process.

Prevalence of Prior Cancer Among Persons Newly Diagnosed With Cancer: An Initial Report From the Surveillance, Epidemiology, and End Results Program

Importance

The US cancer survivor population is rapidly growing. Cancer survivors are frequently excluded from cancer clinical trials and observational research.

Objective

To examine prevalence of prior cancer among individuals newly diagnosed with cancer.

Design, Setting, and Participants

Linked observations across the population-based Surveillance, Epidemiology, and End Results (SEER) program of cancer registries (1975-2013) for 740 990 persons newly diagnosed with cancer from January 2009 through December 2013. Prevalence of prior cancer was estimated by age (<65 years vs ≥65 years) and incident cancer type.

Main Outcomes and Measures

Prevalence of prior cancer was derived from SEER sequence numbers, which represent the order of all primary reportable tumors diagnosed in a lifetime. Incident cancers were categorized as: (1) first or only primary; (2) second order or higher primary in the same cancer site; and (3) second order or higher primary in a different cancer site.

Results

Of 765 843 incident cancers diagnosed between 2009 and 2013, 141 021 (18.4%) represented a second order or higher primary cancer. Overall, approximately one-fourth (25.2%) of older (≥65 years) and 11% of younger adults newly diagnosed with cancer had a history of prior cancer. Prevalence of prior cancer ranged from 3.5% to 36.9% according to incident cancer type and age, with most prior cancers diagnosed in a different cancer site.

Conclusions and Relevance

A substantial proportion of patients diagnosed with incident cancer in the United States have survived a prior cancer. These patients may be excluded from clinical trials and underrepresented in observational research, and little is known about their treatment and survivorship needs. Understanding the nature and impact of prior cancer is critical to improving clinical trial accrual and generalizability, disease outcomes, and patient experience.

Treatment selection bias for chemotherapy persists in colorectal cancer patient cohort studies even in comprehensive propensity score analyses

Introduction

Propensity score methods are increasingly used to address confounding related to treatment selection in observational studies. Studies estimating the effect of chemotherapy in colon cancer (CC) patients, however, often lacked information on pertinent comorbidities and functional status (FS). We assessed to what extent comorbidities and FS impact treatment decisions in colorectal cancer patients and explain the benefit of chemotherapy in stage III CC patients.

Methods

Stage II-III colorectal cancer patients diagnosed in 2003-2014 and recruited into a population-based study were included (N=1102). Associations of comorbidity and FS with treatment patterns were examined with multivariable logistic regression. The contribution of lower comorbidity and higher FS to the benefit of chemotherapy was estimated with propensity score weighted Cox models in 430 stage III CC patients who were followed over a median time of 4.7 years.

Results

In stage II (high-risk) and III CC patients, Charlson comorbidity scores 1, 2 and 3+ were associated with 57%, 66% and 70% lower odds of chemotherapy use, respectively. In combination with older age and poor FS, comorbidity was associated with 97% and 83% decreased odds of adjuvant chemotherapy use in CC and rectal cancer patients, respectively. In stage III CC patients, lower comorbidity and higher FS explained 38% and 24% of the overall and disease-specific survival benefits of chemotherapy, respectively. Selection bias was observed even in the comprehensive models, as chemotherapy was still associated with substantially higher non-disease-specific survival (hazard ratio (HR): 0.66; 95% confidence interval (CI): 0.46-0.92), especially in patients <75 years (HR: 0.33; 95% CI: 0.17-0.63).

Conclusion

Lower comorbidity and higher FS of recipients of chemotherapy explain approximately 40% of the benefits of chemotherapy in stage III CC patients. Regardless of how comprehensive propensity score analyses might be in observational studies, treatment selection bias might persist and affect estimates of treatment effects.

Estimating the optimal rate of adjuvant chemotherapy utilization for stage III colon cancer

Background

Identifying optimal chemotherapy utilization rates can drive improvements in quality of care. We report a benchmarking approach to estimate the optimal rate of adjuvant chemotherapy (ACT) for stage III colon cancer.

Methods

The Ontario Cancer Registry and linked treated records were used to identify ACT utilization. Monte Carlo simulation was used to estimate the proportion of ACT rate variation that could be due to chance alone. The criterion‐based benchmarking approach was used to explore whether socioeconomic or system‐level factors were associated with ACT. We also used the “pared‐mean” approach to identify a benchmark population of hospitals with the highest ACT rates.

Results

The study population included 2801 patients; ACT was delivered to 66% (1861/2801). Monte Carlo simulation suggested that the observed component of variation (15.6%) in ACT rates was within the 95% CI (11.5%‐17.3%) of what could be expected due to chance alone; the nonrandom component of ACT rate variation across hospitals was only 1.5%. There was no difference in hospital ACT rate by teaching status (P = .107), cancer center status (P = .362), or having medical oncology on site (P = .840). Unadjusted ACT rates varied across hospitals (range 44%‐91%, P = .017). The unadjusted benchmark ACT rate was 81% (95%CI 76%‐86%); utilization rate in non‐benchmark hospitals was 65% (95%CI 63%‐66%). However, after adjusting for case mix, the difference in ACT utilization between benchmark and non‐benchmark populations was significantly smaller.

Conclusions

We did not find any system‐level factors associated with the utilization of ACT. Our results suggest that the observed variation in hospital ACT rate is not significantly different from variation due to chance alone. Using the “pared‐mean” approach may significantly overestimate optimal treatment rates if case mix is not considered.

Impact of age on the use of adjuvant treatments in patients undergoing surgery for colorectal cancer: patients with stage III colon or stage II/III rectal cancer

Background

Many older patients don’t receive appropriate oncological treatment. Our aim was to analyse whether there are age differences in the use of adjuvant chemotherapy and preoperative radiotherapy in patients with colorectal cancer.

Methods

A prospective cohort study was conducted in 22 hospitals including 1157 patients with stage III colon or stage II/III rectal cancer who underwent surgery. Primary outcomes were the use of adjuvant chemotherapy for stage III colon cancer and preoperative radiotherapy for stage II/III rectal cancer. Generalised estimating equations were used to adjust for education, living arrangements, area deprivation, comorbidity and clinical tumour characteristics.

Results

In colon cancer 92% of patients aged under 65 years, 77% of those aged 65 to 80 years and 27% of those aged over 80 years received adjuvant chemotherapy (χ²_trends < 0.001). In rectal cancer preoperative radiotherapy was used in 68% of patients aged under 65 years, 60% of those aged 65 to 80 years, and 42% of those aged over 80 years (χ²_trends < 0.001). Adjusting by comorbidity level, tumour characteristics and socioeconomic level, the odds ratio of use of chemotherapy compared with those under age 65, was 0.3 (0.1–0.6) and 0.04 (0.02–0.09) for those aged 65 to 80 and those aged over 80, respectively; similarly, the odds ratio of use of preoperative radiotherapy was 0.9 (0.6–1.4) and 0.5 (0.3–0.8) compared with those under 65 years of age.

Conclusions

The probability of older patients with colorectal cancer receiving adjuvant chemotherapy and preoperative radiotherapy is lower than that of younger patients; many of them are not receiving the treatments recommended by clinical practice guidelines. Differences in comorbidity, tumour characteristics, curative resection, and socioeconomic factors do not explain this lower probability of treatment. Research is needed to identify the role of physical and cognitive functional status, doctors’ attitudes, and preferences of patients and their relatives, in the use of adjuvant therapies.

Electronic supplementary material

The online version of this article (10.1186/s12885-019-5910-z) contains supplementary material, which is available to authorized users.

CDX2 and Muc2 immunohistochemistry as prognostic markers in stage II colon cancer

The treatment for colorectal cancer is largely surgical followed by adjuvant chemotherapy in high-risk cases. In patients with stage II cancer, there is no clear benefit for chemotherapy, and the current tools for assessment of risk are inadequate. A recent study identified that colorectal cancer with a gene signature similar to undifferentiated colonic stem cells was associated with a worse outcome. It was later shown that loss of CDX2 detected by immunohistochemistry (IHC) alone resulted in a worse prognosis and that this could be used to predict patients who would benefit from chemotherapy. Having observed that CDX2 expression can be patchy, we elected to validate these prior results for clinical practice using whole-slide IHC. The pathology of all cases was reviewed, and 3 blocks were selected for CDX2 IHC. We also expanded the panel beyond CDX2 to assess whether other markers in the gene signature including CDX1, Muc2, GPX2, and villin could better predict outcome. Among 210 cases, CDX2 expression was diffusely lost in 11% and focally lost in 23% of cases. There was no difference in survival based on CDX2 expression, but Muc2 loss was associated with reduced survival (hazard ratio, 3.32; 95% confidence interval, 1.20 to 9.20). No significant differences in outcome were identified based on CDX1, GPX2, or villin expression. In keeping with this, assessment of The Cancer Genome Atlas gene expression data demonstrated that decreased Muc2 expression was associated with reduced overall survival. Our results with whole-slide IHC are different from the previous studies and caution against the use of CDX2 in isolation as a prognostic marker in clinical practice. We have identified that loss of Muc2 is associated with reduced survival. This supports the use of the colonic differentiation gene expression signature to identify high-risk patients but cautions against the use of any one IHC-based marker in isolation.

Meeting report from the joint IARC-NCI international cancer seminar series: a focus on colorectal cancer

Despite significant progress in our understanding of the etiology, biology and genetics of colorectal cancer, as well as important clinical advances, it remains the third most frequently diagnosed cancer worldwide and is the second leading cause of cancer death. Based on demographic projections, the global burden of colorectal cancer would be expected to rise by 72% from 1.8 million new cases in 2018 to over 3 million in 2040 with substantial increases anticipated in low- and middle-income countries. In this meeting report, we summarize the content of a joint workshop led by the National Cancer Institute and the International Agency for Research on Cancer, which was held to summarize the important achievements that have been made in our understanding of colorectal cancer etiology, genetics, early detection and treatment and to identify key research questions that remain to be addressed.