Natural History Of Colorectal Cancer Research Articles

Social inequalities in health: How do they influence the natural history of colorectal cancer?

As regards colorectal cancer (CRC) in France, social inequalities in health (SIH) exist. Underprivileged patients are characterized by reduced incidence of CRC and, conversely, by excess mortality. The explanatory mechanisms of the SIHs influencing survival are complex, multidimensional and variable according to healthcare system. Among the most deprived compared to the least deprived patients, SIHs are reflected by lower participation in screening campaigns, and CRC diagnosis is more frequently given at a later stage in an emergency context. During treatment, disadvantaged patients are more at risk of having to undergo open surgery and of enduring severe postoperative complications and belated chemotherapy (when recommended). Study of SIHs poses unusual challenges, as it is necessary not only to pinpoint social deprivation, but also to locate the different treatment facilities existing in a given territorial expanse. In the absence of individualized socioeconomic information, research in France on the social determinants of health is based on duly constituted cancer registries, in which an ecological index of social deprivation, the European Deprivation Index (EDI), provides an aggregate measure of the socioeconomic environment of a given individual in a given geographical setting at a given point in time. All in all, studies on SIHs are justified as means of identification and comprehension of the mechanisms underlying social deprivation, the objective being to more precisely orient programs and practices aimed at combating SIH.

Elevated Adenomatous Polyp Detection Rate Among Alaska Native and American Indian People in Interior Alaska, 2018-2022.

Colorectal cancer (CRC) incidence and mortality are twice as high among Alaska Native people as among non-Hispanic White people in the United States; as such, colonoscopy is a recommended screening test for Alaska Native people. Adenoma detection rate (ADR) is measured in patients at average risk of CRC undergoing initial screening colonoscopy and reflects the prevalence of precancerous polyps in a screened population. We evaluated the ADR among Alaska Native people living in Interior Alaska. This project evaluated the ADR among Alaska Native and American Indian adults aged ≥40 years (N = 460) living in Interior Alaska, using a retrospective medical record review of patients referred for screening colonoscopy from February 1, 2018, through March 31, 2022. The main outcome measure was ADR, stratified by age and sex. The ADR was 45.0% overall: 43.0% among women and 47.1% among men. Among patients aged ≥50 years, the ADR was 67.1%: 62.7% among women and 70.7% among men. Among patients aged 40-49 years, the ADR was 34.4%: 35.3% among women and 33.3% among men. Measured ADR was high among Alaska Native men and women aged ≥50 years in Interior Alaska and in all age groups that were screened. These findings have implications for which CRC screening methods, intervals, and age to begin screening are most appropriate for Alaska Native people, as well as the need for future research on the pathology, etiology, and natural history of CRC in this population.

Sequentially calibrating a Bayesian microsimulation model to incorporate new information and assumptions

BackgroundMicrosimulation models are mathematical models that simulate event histories for individual members of a population. They are useful for policy decisions because they simulate a large number of individuals from an idealized population, with features that change over time, and the resulting event histories can be summarized to describe key population-level outcomes. Model calibration is the process of incorporating evidence into the model. Calibrated models can be used to make predictions about population trends in disease outcomes and effectiveness of interventions, but calibration can be challenging and computationally expensive.MethodsThis paper develops a technique for sequentially updating models to take full advantage of earlier calibration results, to ultimately speed up the calibration process. A Bayesian approach to calibration is used because it combines different sources of evidence and enables uncertainty quantification which is appealing for decision-making. We develop this method in order to re-calibrate a microsimulation model for the natural history of colorectal cancer to include new targets that better inform the time from initiation of preclinical cancer to presentation with clinical cancer (sojourn time), because model exploration and validation revealed that more information was needed on sojourn time, and that the predicted percentage of patients with cancers detected via colonoscopy screening was too low.ResultsThe sequential approach to calibration was more efficient than recalibrating the model from scratch. Incorporating new information on the percentage of patients with cancers detected upon screening changed the estimated sojourn time parameters significantly, increasing the estimated mean sojourn time for cancers in the colon and rectum, providing results with more validity.ConclusionsA sequential approach to recalibration can be used to efficiently recalibrate a microsimulation model when new information becomes available that requires the original targets to be supplemented with additional targets.

PCN191 Modeling the Duration of Protective Effects and Resource Use of Colonoscopy Screening By a Discrete Event Simulation Model Calibrated with German Screening Registry Data

Colorectal cancer (CRC) screening models are valuable tools for projecting long-term effects and resource use for policy decision-making. A new Discrete Event simulation model for the natural history of Colorectal cancer from the Adenoma and Serrated neoplasia pathways (DECAS) was recently developed and calibrated using the German screening colonoscopy registry data, which consist of 5.2 million screening participants between 2003-2014. It was validated against the German national cancer registry data. We aimed to use DECAS to estimate the length of protective effects of colonoscopy screening and the amount of colonoscopy needed in the German context. We used DECAS to simulate a cohort of averaged-risk individuals from age of 20 to 90 for three scenarios: (1) no screening; (2) one colonoscopy at age of 55; (3) two colonoscopies at age of 55 and 65. In the base-case analysis, we assumed the adenoma pathway accounting for 85% of the CRC development and the serrated pathway for the other 15%, as well as a 100% uptake of screening and surveillance colonoscopies. Outcomes of interest were hazard ratios (HR) of CRC-specific mortality under each screening scenario comparing to no screening, and the number of colonoscopies required. DECAS predicted HRs of CRC-specific mortality at approximately 0.2 for both screening scenarios after 25 years of follow up, and the trend of both mortality HRs was still decreasing. The average numbers of colonoscopies required were 1,300 and 2,174 per 1,000 for once and twice colonoscopy screening, respectively. We also varied alternative screening and surveillance participation rates for sensitivity analyses. The modeling results from DECAS confirmed the long-term protective effects of colonoscopy screening and provided an estimation of the number of colonoscopies required in the German context. We will further apply DECAS to perform economic evaluations on various CRC screening strategies and policies.

Projecting total costs and health consequences of increasing mt-sDNA utilization for colorectal cancer screening from the payer and integrated delivery network perspectives

Aims: To evaluate total costs and health consequences of a colorectal cancer (CRC) screening program with colonoscopy, fecal immunochemical tests (FIT), and expanded use of multitarget stool DNA (mt-sDNA) from the perspectives of Integrated Delivery Networks (IDNs) and payers in the United States.Materials and methods: We developed a budget impact and cost-consequence model that simulates CRC screening for eligible 50- to 75-year-old adults. A status quo scenario and an increased mt-sDNA scenario were modeled. The status quo includes the current screening mix of colonoscopy (83%), FIT (11%), and mt-sDNA (6%) modalities. The increased mt-sDNA scenario increases mt-sDNA utilization to 28% over 10 years. Costs for both the IDN and the payer perspectives incorporated diagnostic and surveillance colonoscopies, adverse events (AEs), and CRC treatment. The IDN perspective included screening program costs, composed of direct nonmedical (e.g. patient navigation) and indirect (e.g. administration) costs. It was assumed that IDNs do not incur the costs for stool-based screening tests or bowel preparation for colonoscopies.Results: In a population of one million covered lives, the 10-year incremental cost savings incurred by increasing mt-sDNA utilization was $19.6 M for the IDN and $4.4 M for the payer. The incremental savings per-person-per-month were $0.16 and $0.04 for the IDN and payer, respectively. For both perspectives, increased diagnostic colonoscopy costs were offset by reductions in screening colonoscopies, surveillance colonoscopies, and AEs. Extending screening eligibility to 45- to 75-year-olds slightly decreased the overall cost savings.Limitations: The natural history of CRC was not simulated; however, many of the utilized parameters were extracted from highly vetted natural history models or published literature. Direct nonmedical and indirect costs for CRC screening programs are applied on a per-person-per modality basis, whereas in reality some of these costs may be fixed.Conclusions: Increased mt-sDNA utilization leads to fewer colonoscopies, less AEs, and lower overall costs for both IDNs and payers, reducing overall screening program costs and increasing the number of cancers detected while maintaining screening adherence rates over 10 years.

Challenges With Colorectal Cancer Family History Assessment—Motivation to Translate Polygenic Risk Scores Into Practice

Challenges With Colorectal Cancer Family History Assessment—Motivation to Translate Polygenic Risk Scores Into Practice

Natural history of colorectal cancer: a Meta-analysis on global prospective cohort studies

Objective: To acknowledge the availability and rates of annual transition of outcomes during the progression and regression stages of colorectal cancer (CRC) and related diseases, by pooling global follow-up studies on the natural history of CRC. Methods: Till March, 2017, data was collected through systematic literature review over multiple databases, including PubMed, Embase, Cochrane and Chinese Biology Medicine (CBM) disc. Information regarding the characteristics, classification system of health states, related outcomes and incidence rates on CRC or high-risk adenoma for the surveillance cohorts of the studies, were extracted and summarized. Both Meta and sensitivity analyses were performed on those outcomes if they appeared in more than 3 studies, using the random effects model. Annual transition rate with 95%CI was used to estimate each of the outcomes, Quality of the studies was assessed, using the Newcastle-Ottawa Scale. Results: A total of 29 cohort studies were included, with the mean follow-up period as 5.7 years. All studies except one, focused on adenoma-carcinoma pathway and reported the outcome parameters of adenomas by different risk, and some reported the findings on different sizes (n=6) of adenomas. These cohorts were divided into three groups (normal status, with low-risk or high-risk adenoma) according to the status of baseline endoscopic pathologic findings. Their available outcome parameters, corresponding number of involved articles, aggregated sample size and pooled annual transition rates were presented. Six parameters were obtained in the normal cohorts, including those from normal to low-risk adenoma (16 articles, 58 235, 0.030: 0.024-0.037), to high-risk adenoma (17 articles, 62 089, 0.003: 0.002-0.004), to diminutive adenoma (<5 mm, 4 articles, 1 277, 0.021: 0.013-0.029), to small adenoma (6-9 mm, 4 articles, 1 277, 0.006: 0.001-0.010), to large adenoma (≥10 mm, 7 articles, 3 531, 0.002: 0.000-0.003) and to CRC (19 articles, 104 836, 0.000 3: 0.000 2-0.000 5). Three parameters were obtained in low-risk adenoma in cohorts with polypectomy findings, including recurrence (9 articles, 4 788, 0.109: 0.062-0.157) from low-risk adenoma after polypectomy to high-risk adenoma (10 articles, 5 736, 0.009: 0.004-0.013) and to CRC (12 articles, 11 347, 0.000 6: 0.000 4-0.000 8). Three parameters were obtained on high-risk adenoma from cohorts with polypectomy findings, including recurrence (12 articles, 7 030, 0.038: 0.028-0.048) from high-risk adenoma after polypectomy to low-risk adenoma (8 articles, 2 489, 0.133: 0.081-0.185) and CRC (14 articles, 14 899, 0.002: 0.001-0.003). Except for normal to low-risk adenomas, results from the sensitivity analysis for the other parameters showed stable. Of the included studies, two presented incidence rates of CRC in different clinical stages and the another two were focusing on the parameters related to serrated pathway. Conclusions: Globally, follow-up studies reported data on natural history of colorectal cancer is of paucity. Compared to the "adenoma-carcinoma" pathway, transition parameters of the serrated lesion pathway are more limited. This Meta-analysis provided convincing evidence for optimizing the strategies regarding follow-up program on the disease, using the baseline endoscopic findings from global CRC Screening Program. These results also offered strong data-related support for Chinese population- specific interventional model on colorectal cancer.

Colorectal Cancer in the Young: Does Screening Make Sense?

Colorectal cancer (CRC) screening is recommended to reduce CRC mortality. This review outlines key factors to consider when recommending screening, including disease burden, screening benefits and harms, and remaining knowledge gaps. In response to increasing rates of CRC incidence among younger (age < 50years) adults, the American Cancer Society published guidelines in May 2018 recommending average-risk CRC screening beginning at age 45 (vs. 50) years. Rates of young-onset CRC have increased in the USA since the early 1990s. However, there is very little empirical evidence of screening effectiveness in younger adults, and few studies have reported harms of routine screening in this age group. Further, we know little about the natural history of CRC in younger adults. Uncertainty surrounding the efficacy of CRC screening in younger adults suggests the benefits may be small. Precision cancer screening-or modified screening regimens based on risk-may improve the balance of screening benefits and harms beyond conventional age-based strategies.

Surveillance, Epidemiology, and End Results (SEER) and SEER-Medicare Databases: Use in Clinical Research for Improving Colorectal Cancer Outcomes.

The Surveillance, Epidemiology, and End Results (SEER) program is a clinical database, funded by the National Cancer Institute (NCI), which was created to collect cancer incidence, prevalence, and survival data from U.S. cancer registries. By capturing approximately 30% of the U.S. population, it serves as a powerful resource for researchers focused on understanding the natural history of colorectal cancer and improvement in patient care. The linked SEER-Medicare database is a robust database allowing investigators to perform studies focusing on health disparities, quality of care, and cost of treatment in oncologic disease. Since its infancy in the early 1970s, the database has been utilized for thousands of studies resulting in novel publications that have shaped our management of colorectal cancer among other malignancies.

Nonidentifiability in Model Calibration and Implications for Medical Decision Making.

Calibration is the process of estimating parameters of a mathematical model by matching model outputs to calibration targets. In the presence of nonidentifiability, multiple parameter sets solve the calibration problem, which may have important implications for decision making. We evaluate the implications of nonidentifiability on the optimal strategy and provide methods to check for nonidentifiability. We illustrate nonidentifiability by calibrating a 3-state Markov model of cancer relative survival (RS). We performed 2 different calibration exercises: 1) only including RS as a calibration target and 2) adding the ratio between the 2 nondeath states over time as an additional target. We used the Nelder-Mead (NM) algorithm to identify parameter sets that best matched the calibration targets. We used collinearity and likelihood profile analyses to check for nonidentifiability. We then estimated the benefit of a hypothetical treatment in terms of life expectancy gains using different, but equally good-fitting, parameter sets. We also applied collinearity analysis to a realistic model of the natural history of colorectal cancer. When only RS is used as the calibration target, 2 different parameter sets yield similar maximum likelihood values. The high collinearity index and the bimodal likelihood profile on both parameters demonstrated the presence of nonidentifiability. These different, equally good-fitting parameter sets produce different estimates of the treatment effectiveness (0.67 v. 0.31 years), which could influence the optimal decision. By incorporating the additional target, the model becomes identifiable with a collinearity index of 3.5 and a unimodal likelihood profile. In the presence of nonidentifiability, equally likely parameter estimates might yield different conclusions. Checking for the existence of nonidentifiability and its implications should be incorporated into standard model calibration procedures.

The American College of Surgeons National Cancer Database: A successful initiative in improving colorectal cancer outcomes

The National Cancer Data Base (NCDB) was created by the American College of Surgeons and the American Cancer Society, in an effort to improve cancer care, by collecting data about patients treated for oncologic disease on a national level. In capturing more than 70% of patients treated for malignancy in the United States, it has allowed researchers to understand the natural history of colorectal cancer (CRC) and analyze the progression and efficacy of therapeutic strategies aimed at CRC. Due to its focus on oncologic disease alone, the NCDB has also allowed subset analysis of specific tumors and patient populations as well as the validation and refinement of staging strategies. While data from the NCDB have contributed significantly to the study of colorectal cancer, the database remains underutilized with regard to its potential for furthering the understanding of colorectal cancers and improving the care of patients with these tumors.

Mo1996 Validation of Simulation Models to the UK Flexiscope Trial to Inform the Natural History of Colorectal Cancer

Mo1996 Validation of Simulation Models to the UK Flexiscope Trial to Inform the Natural History of Colorectal Cancer

Family history and the natural history of colorectal cancer: systematic review.

Family history of colorectal cancer (CRC) is a known risk factor for CRC and encompasses both genetic and shared environmental risks. We conducted a systematic review to estimate the impact of family history on the natural history of CRC and adherence to screening. We found high heterogeneity in family-history definitions, the most common definition being one or more first-degree relatives. The prevalence of family history may be lower than the commonly cited 10%, and confirms evidence for increasing levels of risk associated with increasing family-history burden. There is evidence for higher prevalence of adenomas and of multiple adenomas in people with family history of CRC but no evidence for differential adenoma location or adenoma progression by family history. Limited data regarding the natural history of CRC by family history suggest a differential age or stage at cancer diagnosis and mixed evidence with respect to tumor location. Adherence to recommended colonoscopy screening was higher in people with a family history of CRC. Stratification based on polygenic and/or multifactorial risk assessment may mature to the point of displacing family history-based approaches, but for the foreseeable future, family history may remain a valuable clinical tool for identifying individuals at increased risk for CRC.

Development and progression of colorectal cancer based on follow-up analysis.

Elucidating the pathway of colorectal cancer development and progression can lead to identification of lesions that must be treated appropriately. The aim of the present review was to summarize the development and progression of colorectal cancer based on radiological and endoscopic follow-up analyses. These studies revealed several characteristic findings, including that initial morphology with progression to advanced cancer was most commonly 0-Is, followed by 0-IIa. Based on the doubling time, 0-Ip grew slowly in comparison with other morphologies. The observation period from adenomas measuring <10 mm to intramucosal cancers was more than 5 years. This makes it difficult to draw any accurate conclusions about the natural history of colorectal cancer based on follow-up observation alone and it is difficult to exclude the selection bias because of the difficulty of follow up for flat and depressed tumor. However, the only reliable way to elucidate the natural history is to accumulate cases.

Prospective Investigation of Body Mass Index, Colorectal Adenoma, and Colorectal Cancer in the Prostate, Lung, Colorectal, and Ovarian Cancer Screening Trial

Obesity has consistently been linked to an increased risk of colorectal cancer, particularly among men. Whether body mass index (BMI) differentially influences the risk across the stages of colorectal cancer development remains unclear. We evaluated the associations of BMI with colorectal adenoma incidence, adenoma recurrence, and cancer in the context of a large screening trial, in which cases and controls had an equal chance for disease detection. We prospectively evaluated the association between baseline BMI and the risk of incident distal adenoma (1,213 cases), recurrent adenoma (752 cases), and incident colorectal cancer (966 cases) among men and women, ages 55 to 74 years, randomly assigned to receive flexible sigmoidoscopy screening as part of the Prostate, Lung, Colorectal, and Ovarian Cancer Screening Trial. We calculated odds ratios (ORs) and 95% CIs for adenoma incidence and recurrence, and hazard ratios (HRs) and 95% CIs for colorectal cancer incidence, using multivariable-adjusted models. Compared with normal-weight men (18.5 to 24.9 kg/m(2)), obese men (≥ 30 kg/m(2)) had significantly higher risk of incident adenoma (OR, 1.32; 95% CI, 1.06 to 1.65) and colorectal cancer (HR, 1.48; 95% CI, 1.16 to 1.89) and a borderline increased risk of recurrent adenoma (OR, 1.50; 95% CI, 0.98 to 2.30). No associations were observed for either adenoma or cancer in women. Data from this large prospective study suggest that obesity is important throughout the natural history of colorectal cancer, at least in men, and colorectal cancer prevention efforts should encourage the achievement and maintenance of a healthy body weight in addition to regular screenings.

Special Issue on Precision Risk Stratification-Based Screening in Colorectal Cancer

Cancer remains a formidable public health burden, as over half a million Americans succumb to this disease each year. The fight to vanquish cancer is stronger than ever. The pace of acquisition of new, cutting-edge scientific knowledge about the complex biology of cancer, and the development of technologies, targeted therapeutics and innovative approaches to prevent, detect and treat the disease have accelerated considerably over the past decade. Hence, in just over a century we have witnessed an extraordinary evolution of medical practice from seeking to understand disease in a physician-directed healthcare paradigm, to evidence-based medicine, and on to the modern era of emerging personalized, predictive, precision medicine (which applies predictive and prognostic biomarkers and patient-specific attributes using a “personalized lifespan approach”). During the past year we have witnessed not only a multi-faceted national effort to improve quality and value of cancer care aligned with the Institute for Healthcare Improvement's “triple aim” Initiative [improving the individual patient care experience, the health of populations, and thereby the efficiency and cost of care], but also realized several major clinical advances in cancer treatment [http://www.ihi.org/offerings/Initiatives/TripleAim/Pages/default.aspx]. In 2012 alone, the FDA approved seven new targeted systemic agents and expanded the anti-cancer indications for five existing agents. Noteworthy progress has been made in overcoming treatment resistance (combining targeted drugs, use of multi-targeted agents, targeting new pathways), understanding molecular drivers of cancer and tumor heterogeneity across the genomic landscape to include gene-environment interactions, advancing precision medicine, improving and enabling risk stratification-based screening and early detection. To this latter point, a minimally invasive technique (flexible sigmoidoscopy) has been shown in a large randomized clinical trial to significantly reduce both incidence (by 21%; relative risk, 0.79; 95% confidence interval [CI], 0.72 to 0.85; P<0.001) and overall colorectal cancer mortality (by 26%; relative risk, 0.74; 95% CI, 0.63 to 0.87; P<0.001) [N Engl J Med. 2012 Jun 21;366(25):2345-57]. This represents a major advance in cancer screening and early disease detection. It is decidedly poised to transform population-based screening, and to support concerted efforts to unravel socioeconomic disparities in cancer screening. What's more, this safe and effective screening approach will be used to educate screening populations about the importance of early detection, and could inspire wide-ranging compliance with recommended colorectal screening guidelines. The current special edition of the Journal of Cancer is centered on colorectal cancer and it highlights advances made in the prevention, screening, early detection, and treatment of this disease. It communicates an ambitious vision aimed at conquering colorectal cancer, and provides recommendations for leveraging innovative technological advances, particularly those that provide insights into patient-specific tumor biology, genetic make-up and epigenetic regulation. It emphasizes the way forward through progress made in screening for colorectal cancer in an ethnically and socio-economically diverse population with equal access to care. The special edition further emphasizes safe, effective, quality-based, innovative colorectal cancer care early detection and individualized precision medicine through Precision Risk Stratification-Based Screening. The principal aim of this risk identification and screening approach is to identify patients at risk for or diagnoses patients early in the natural history of colorectal cancer. It further defines evidence-based methods by which to avoid the toxicity of systemic therapy in appropriately risk-stratified patients identified as low risk for disease recurrence that are likely cured by surgery alone; appropriately classify patients with clinically latent or stable residual disease for whom systemic therapy can be withheld, and accurately recognize those high-risk node-negative patients with colorectal cancer or those with treatment-responsive disease likely to progress and treat them at the optimal time in the course of their disease. This special edition charts an ambitious and attainable way forward, and allows us ample basis by which to imagine a world without cancer.

Patients at risk for peritoneal surface malignancy of colorectal cancer origin: the role of second look laparotomy.

Peritoneal surface malignancy (PSM) is a frequent occurrence in the natural history of colorectal cancer (CRC). Although significant advances have been made in screening of CRC, similar progress has yet to be made in the early detection of PSM of colorectal cancer origin. The fact that advanced CRC can be confined to the peritoneal surface without distant dissemination forms the basis for aggressive multi-modality therapy consisting of cytoreductive surgery (CRS) plus hyperthermic intra-peritoneal chemotherapy (HIPEC), and neoadjuvant and/or adjuvant systemic therapy. Reported overall survival with complete CRS+HIPEC exceeds that of systemic therapy alone for the treatment of PSM from CRC, underscoring the advantage of this multi-modality therapeutic approach. Patients with limited peritoneal disease from CRC can undergo complete cytoreduction, which is associated with the best reported outcomes. As early or limited peritoneal carcinomatosis is undetectable by conventional imaging modalities, second look laparotomy is an important means to identify disease in high-risk patients at a stage most amenable to complete cytoreduction. This review focuses on the identification of patients at risk for PSM from CRC and discusses the role of second look laparotomy.

Estimated Mean Sojourn Time Associated with Hemoccult SENSA for Detection of Proximal and Distal Colorectal Cancer

Sojourn time is the length of the preclinical screen-detectable phase, a period when a test can detect asymptomatic disease. Mean sojourn time (MST) is an important factor in determining appropriate screening intervals. Available estimates of MST for colorectal cancer (CRC) are imprecise and are associated with the older Hemoccult II test. This article presents MST estimates associated with the newer Hemoccult SENSA test and describes differences in MST by the location of cancer in the colorectum and age at the time of screening. MST was estimated from a cohort of 42,079 patients who underwent Hemoccult SENSA between January 1, 1997 and December 31, 2010. The precision of MST estimates was improved by incorporating information from a meta-analysis of the sensitivity of Hemoccult SENSA into the analytic model. Estimated MST for cancers in the proximal and distal colorectum, with 95% credible intervals (CrI) in years, were: 3.86 (1.55-6.91) and 3.35 (2.11-4.93) among 45- to 54-year olds; 3.78 (2.18-5.77) and 2.24 (1.48-3.17) among 55- to 64-year olds; and 2.70 (1.41-4.31) and 2.10 (1.34-3.04) among 65- to 74-year olds. MST associated with Hemoccult SENSA was longer for CRC in the proximal versus distal colon. We found no evidence that MST increases with age and some evidence that it may decrease. These results add new information about the natural history of CRC and information about the performance of Hemoccult SENSA.

Multimodal treatment of peritoneal malignancies - results of the implantation in a tertiary hospital

INTRODUCTION: Peritoneal carcinomatosis is a condition that may be present in the natural history of colorectal cancer and some other tumors, such as pseudomyxoma peritonei. It has been associated with poor prognosis. The treatment for patients with this condition, up until recently, was systemic chemotherapy or palliative care to relieve the pain and suffering caused by peritoneal dissemination of certain cancers. Promising results, however, have been reported after the implementation of radical cytoreductive surgery followed by peroperative hyperthermic intraperitoneal chemotherapy. OBJECTIVE: To evaluate the results of cytoreductive surgery and peroperative hyperthermic intraperitoneal chemotherapy (HIPEC) in patients with peritoneal carcinomatosis secondary to colorectal cancer and pseudomyxoma peritonei. RESULTS: We retrospectively evaluated 24 patients from 2004 to 2011. Mean age was 51.31 years, and 54% were female. The primary diagnosis in 50.01% of the cases was pseudomyxoma peritonei, 41.66%, of colon cancer, and 8.33%, of mesothelioma. The overall complication rate was around 83%, two patients (8%) subsequently died between the 8th and 30th postoperative day. There was an association between the peritoneal carcinomatosis index (PCI) and operative time. The one-year survival rate in the group examined was 60% for colon cancer, and 78.5% for pseudomyxoma. Overall survival was 50% in three years. CONCLUSION: cytoreductive surgery combined with HIPEC is a treatment option for patients with peritoneal carcinomatosis of colorectal origin and pseudomyxoma. Despite the high rate of peroperative complications (83%), it was possible to achieve a superior survival rate in relation to conventional treatments reported in the literature.

Silent ulcerative colitis adjacent to a regular sigmoid adenocarcinoma

There have been studies trying to elucidate the large spectrum and the variety of inflammatory bowel disease (IBD)-related colorectal cancer manifestations and natural history. A 57-year-old male patient underwent a regular screening colonoscopy in our department, which revealed a flat ulcerated mass in the sigmoid whereas the remaining bowel was normal on endoscopic appearance. Biopsies from the mass were compatible with sigmoid adenocarcinoma and the patient underwent left hemicolectomy. Pathology examination of the resected specimen also diagnosed ulcerative colitis adjacent to cancer. The otherwise healthy patient denied any history that could be related to IBD symptoms. Patient was started on 1.6 g of mesalazine and was advised to adhere to an endoscopic surveillance program. This case points toward a need for a more thorough understanding of the natural history of colorectal cancer in IBD to set clinically meaningful guidelines.