Efficacy of annual colonoscopic surveillance in individuals with hereditary nonpolyposis colorectal cancer

Colorectal cancer and advanced adenoma characteristics according to causative mismatch repair gene variant in Japanese colorectal surveillance for Lynch syndrome

BACKGROUND

The optimal interval of colonoscopy (CS) surveillance in cases with Lynch syndrome (LS), and stratification according to the causative mismatch repair gene mutation, has received much attention. To verify a feasible and effective CS surveillance strategy, we investigated the colorectal cancer (CRC) incidence at different intervals and the characteristics of precancerous colorectal lesions of LS cases.

METHODS

This retrospective multicenter study was conducted in Japan. CRCs and advanced adenomas (AAs) in 316 LS cases with germline pathogenic variants (path_) were analyzed according to the data of 1,756 registered CS.

RESULTS

The mean time interval for advanced CRCs (ACs) detected via CS surveillance was 28.7 months (95% confidence interval: 13.8-43.5). The rate of AC detection within (2.1%) and beyond 2 years (8.7%) differed significantly (p = 0.0003). AAs accounted for 43%, 46%, and 41% of lesions < 10 mm in size in the MLH1-, MSH2-, and MSH6-groups, respectively. The lifetime incidence of metachronous CRCs requiring intestinal resection for path_MLH1, path_MSH2, and path_MSH6 cases was 34%, 23%, and 14% in these cases, respectively. The cumulative CRC incidence showed a trend towards a 10-year delay for path_MSH6 cases as compared with that for path_MLH1 and path_MSH2 cases.

CONCLUSIONS

In cases with path_MLH1, path_MSH2, and path_MSH6, maintaining an appropriate CS surveillance interval of within 2 years is advisable to detect of the colorectal lesion amenable to endoscopic treatment. path_MSH6 cases could be stratified with path_MLH1 and MSH2 cases in terms of risk of metachronous CRC and age of onset.

Cascade genetic testing: an underutilized pathway to equitable cancer care?

The Precision Medicine Initiative was launched upon the potential of genomic information to tailor medical care. Cascade genetic testing represents a powerful application of precision medicine and involves the process of familial diffusion or the "cascade" of genomic risk information. When an individual (proband) is found to carry a cancer-associated germline pathogenic mutation, the information should be cascaded or shared with at-risk relatives. First degree relatives have a 50% likelihood of carrying the same cancer-associated mutation. This process of cascade testing offers at-risk relatives the opportunity for genetic testing and, for those who also carry the cancer-associated mutation, genetically targeted primary disease prevention through intensive cancer surveillance, chemoprevention and risk-reducing surgery, reducing morbidity and preventing mortality. Cascade testing has been designated by the Centers for Disease Control and Prevention as a Tier 1 genomic application for hereditary breast and ovarian cancer. In this manuscript we describe a cascade genetic testing and in particular focus on its potential to provide necessary care to medically underserved and vulnerable populations.

Emerge of colorectal cancer in Lynch syndrome despite colonoscopy surveillance: A challenge of hide and seek

Even with colonoscopy surveillance, Lynch syndromes (LS) carriers still develop colorectal cancer (CRC). The cumulative incidence of CRCs under colonoscopy surveillance varies depending on the affected mismatch repair (MMR) gene. However, the precise mechanisms driving these epidemiological patterns remain incompletely understood. In recent years, several potential mechanisms explaining the occurrence of CRCs during colonoscopy surveillance have been proposed in individuals with and without LS. These encompass biological factors like concealed/accelerated carcinogenesis through a bypassed adenoma stage and accelerated progression from adenomas. Alongside these, various colonoscopy-related factors may contribute to formation of CRCs under colonoscopy surveillance, like missed yet detectable (pre)cancerous lesions, detected yet incompletely removed (pre)cancerous lesions, and colonoscopy-induced carcinogenesis due to tumor cell reimplantation. In this comprehensive literature update, we reviewed these potential factors and evaluated their relevance to each MMR group in an attempt to raise further awareness and stimulate research regarding this conflicting phenomenon.

Integration and usability of a digital cancer risk stratification tool to optimize identification of patients at risk for hereditary cancers: A pilot study

BACKGROUND

Patients with a personal or family history of cancer may have elevated risk of developing future cancers, which often remains unrecognized due to lapses in screening. This pilot study assessed the usability and clinical outcomes of a cancer risk stratification tool in a gynecologic oncology clinic.

METHODS

New gynecologic oncology patients were prompted to complete a commercially developed personal and family history-based risk stratification tool to assess eligibility for genetic testing using National Comprehensive Cancer Network criteria and estimated lifetime breast cancer risk using the Tyrer-Cuzick model. After use of the risk stratification tool, usability was assessed via completion rate and the System Usability Scale, and health literacy was assessed using the BRIEF Health Literacy Screening Tool.

RESULTS

130 patients were prompted to complete the risk stratification tool; 93 (72%) completed the tool. Race and ethnicity and insurance type were not associated with tool completion. The median System Usability Scale score was 83 out of 100 (interquartile range, 60-95). Health literacy positively correlated with perceived usability. Public insurance and race or ethnicity other than non-Hispanic White was associated with lower perceived usability. Sixty (65%) patients met eligibility criteria for genetic testing, and 21 (38% of 56 eligible patients) were candidates for enhanced breast cancer screening based on an estimated lifetime breast cancer risk of ≥20%.

CONCLUSIONS

A majority of patients completed the digital cancer risk stratification tool. Older age, lower health literacy, public insurance, and race or ethnicity other than non-Hispanic White were associated with lower perceived tool usability.

Do people with hereditary cancer syndromes inform their at-risk relatives? A systematic review and meta-analysis

Purpose

To evaluate rates of familial disclosure of hereditary cancer syndrome information.

Methods

A systematic review and meta-analysis was conducted in accordance with PRISMA guidelines (PROSPERO no.: CRD42020134276). Key electronic databases were searched to identify studies evaluating hereditary cancer syndrome cascade relative disclosure. Eligible studies were subjected to meta-analysis.

Results

Thirty-four studies met inclusion criteria. Among 11,711 included relatives, 70% (95% CI 60 - 78%) were informed of their risk of carrying a cancer-associated pathogenic variant; of 2,875 relatives informed of their risk who were evaluated for uptake of cascade testing, 43% (95% CI 27 - 61%) completed testing. Rates of disclosure were higher among female vs male relatives (79% [95% CI 73% - 84%] vs 67% [95% CI 57% - 75%]) and first-degree vs second-degree relatives (83% [95% CI 77% - 88%] vs 58% [95% CI 45 - 69%]).

Conclusion

Nearly one-third of at-risk relatives remain uninformed of their risk of carrying a cancer-associated pathogenic variant. Even among those informed, fewer than half subsequently complete genetic testing, representing a critical missed opportunity for precision cancer prevention.

Innovation

Five studies evaluating interventions to improve disclosure rates were generally ineffective. Urgent work is needed to elucidate barriers to relative disclosure by probands to develop targeted interventions that can optimize proband-mediated cascade genetic testing rates.

Incidence and prevalence of advanced colorectal neoplasia in Lynch syndrome

BACKGROUND AND AIMS

Lynch syndrome (LS) is the most common hereditary cause of colorectal cancer (CRC) and endometrial cancer (EC). Although colonoscopy reduces CRC in LS, the protection is variable. We assessed the prevalence and incidence of neoplasia in LS during surveillance colonoscopy in the United States and factors associated with advanced neoplasia.

METHODS

Patients with LS undergoing ≥1 surveillance colonoscopy and with no personal history of invasive CRC or colorectal surgery were included. Prevalent and incident neoplasia was defined as occurring <6 months before and ≥6 months after germline diagnosis of LS, respectively. We assessed advanced adenoma (AA), CRC, and the impact of mismatch repair pathogenic variant (PV) and typical LS cancer history (personal history of EC and/or family history of EC/CRC) on outcome.

RESULTS

A total of 132 patients (inclusive of 112 undergoing prevalent and incident surveillance) were included. The median examination interval and duration of prevalent and incident surveillance was .88 and 1.06 years and 3.1 and 4.6 years, respectively. Prevalent and incident AA were detected in 10.7% and 6.1% and invasive CRC in 0% and 2.3% of patients. All incident CRC occurred in MSH2 and MLH1 PV carriers and only 1 (.7%) while under surveillance in our center. AAs were detected in both LS cancer history cohorts and represented in all PVs.

CONCLUSIONS

In a U.S. cohort of LS, advanced neoplasia rarely occurred over annual surveillance. CRC was diagnosed only in MSH2/MLH1 PV carriers. AAs occurred regardless of PV or LS cancer history. Prospective studies are warranted to confirm our findings.

Chatbot Artificial Intelligence for Genetic Cancer Risk Assessment and Counseling: A Systematic Review and Meta-Analysis

PURPOSE

Most individuals with a hereditary cancer syndrome are unaware of their genetic status to underutilization of hereditary cancer risk assessment. Chatbots, or programs that use artificial intelligence to simulate conversation, have emerged as a promising tool in health care and, more recently, as a potential tool for genetic cancer risk assessment and counseling. Here, we evaluated the existing literature on the use of chatbots in genetic cancer risk assessment and counseling.

METHODS

A systematic review was conducted using key electronic databases to identify studies which use chatbots for genetic cancer risk assessment and counseling. Eligible studies were further subjected to meta-analysis.

RESULTS

Seven studies met inclusion criteria, evaluating five distinct chatbots. Three studies evaluated a chatbot that could perform genetic cancer risk assessment, one study evaluated a chatbot that offered patient counseling, and three studies included both functions. The pooled estimated completion rate for the genetic cancer risk assessment was 36.7% (95% CI, 14.8 to 65.9). Two studies included comprehensive patient characteristics, and none involved a comparison group. Chatbots varied as to the involvement of a health care provider in the process of risk assessment and counseling.

CONCLUSION

Chatbots have been used to streamline genetic cancer risk assessment and counseling and hold promise for reducing barriers to genetic services. Data regarding user and nonuser characteristics are lacking, as are data regarding comparative effectiveness to usual care. Future research may consider the impact of chatbots on equitable access to genetic services.

The Role of Colonoscopy in the Management of Individuals with Lynch Syndrome: A Narrative Review

The history of Lynch syndrome changed definitively in 2000, when a study published in Gastroenterology demonstrated a significant reduction in mortality among individuals with Lynch syndrome who undergo regular endoscopic surveillance. As a consequence of this clinical evidence, all scientific societies developed guidelines, which highlighted the role of colonoscopy in the management of Lynch syndrome, especially for individuals at high risk of colorectal cancer. Over the years, these guidelines were modified and updated. Specialized networks were developed in order to standardize endoscopic surveillance programs and evaluate all the clinical data retrieved by the results of colonoscopies performed for both the screening and the surveillance of individuals with Lynch syndrome. Recent data show that the impact of colonoscopy (with polypectomy) on the prevention of colorectal cancer in individuals with Lynch syndrome is less significant than previously thought. This narrative review summarizes the current discussion, the hypotheses elaborated and the algorithms depicted for the management of individuals with Lynch Syndrome on the basis of the recent data published in the literature.

[Surgical strategies for hereditary colorectal cancer]

Hereditary colorectal cancer (hCRC) represents a major diagnostic and therapeutic challenge. In addition to the usual diagnostic methods, the family history, histological confirmation and mutation analysis play an important role in identifying the type of hereditary CRC. The diagnosis and classification of hCRC are carried out based on the anamnesis, clinical presentation and histology and the further treatment is determined depending on the underlying type of hCRC. For familial adenomatous polyposis (FAP) coloproctomucosectomy after the end of puberty is always recommended, whereas the treatment recommendations for other forms, such as attenuated FAP (aFAP), MUTYH-associated polyposis (MAP) and hereditary nonpolyposis colon cancer (HNPCC, Lynch syndrome), range from close surveillance and endoscopic control, through segmental resection up to colectomy. Irrespective of the type of hCRC, the treatment regimens necessitate an individualized approach and require close interdisciplinary cooperation. When colorectal resection is performed, minimally invasive procedures should principally be prioritized and some studies could demonstrate a potential benefit of robotic surgery compared to laparoscopy.

Discordance between germline genetic findings and abnormal tumor immunohistochemistry staining of mismatch repair proteins in individuals with suspected Lynch syndrome

Background and Aims

Tumor immunohistochemical staining (IHC) of DNA mismatch repair (MMR) proteins is often used to guide germline genetic testing and variant classification for patients with suspected Lynch syndrome. This analysis examined the spectrum of germline findings in a cohort of individuals showing abnormal tumor IHC.

Methods

We assessed individuals with reported abnormal IHC findings and referred for testing with a six-gene syndrome-specific panel (n=703). Pathogenic variants (PVs) and variants of uncertain significance (VUS) in MMR genes were designated expected/unexpected relative to IHC results.

Results

The PV positive rate was 23.2% (163/703; 95% confidence interval [CI], 20.1%-26.5%); 8.0% (13/163; 95% CI, 4.3%-13.3%) of PV carriers had a PV in an unexpected MMR gene. Overall, 121 individuals carried VUS in MMR genes expected to be mutated based on IHC results. Based on independent evidence, in 47.1% (57/121; 95% CI, 38.0%-56.4%) of these individuals the VUSs were later reclassified as benign and in 14.0% (17/121; 95% CI, 8.4%-21.5%) of these individuals the VUSs were reclassified as pathogenic.

Conclusions

Among patients with abnormal IHC findings, IHC-guided single-gene genetic testing may miss 8% of individuals with Lynch syndrome. In addition, in patients with VUS identified in MMR genes predicted to be mutated by IHC, extreme caution must be taken when the IHC results are considered in variant classification.

Endoscopic surveillance of Lynch syndrome at a highly specialized center in Sweden: An observational study of interval colorectal cancer and individual risk factors

Introduction

Lynch syndrome (LS) is the most common hereditary cause of colorectal cancer (CRC). In order to detect CRCs amongst LS patients, regular colonoscopies are recommended. However, an international agreement on an optimal surveillance interval has not yet been reached. In addition, few studies have investigated factors that could potentially increase the CRC risk amongst LS patients.

Aims

The primary aim was to describe the frequency of CRCs detected during endoscopic surveillance and to estimate the interval from a clean colonoscopy to CRC detection amongst LS patients. The secondary aim was to investigate individual risk factors, including sex, LS genotype, smoking, aspirin use and body mass index (BMI), on CRC risk amongst patients that develop CRC before and during surveillance.

Material and methods

Clinical data and colonoscopy findings from 366 LS patients' 1437 surveillance colonoscopies were collected from medical records and patient protocols. Logistic regression and Fisher's exact test were used to investigate associations between individual risk factors and CRC development. Mann-Whitney U test was used to compare the distribution of TNM stages of CRC detected before surveillance and after index.

Results

CRC was detected in 80 patients before surveillance and in 28 patients during surveillance (10 at index and 18 after index). During the surveillance programme, CRC was detected within 24 months in 65% of the patients, and after 24 months within 35% of the patients. CRC was more common amongst men, previous and current smokers, and the odds of developing CRC also increased with an increasing BMI. CRCs were more often detected amongst MLH1 and MSH2 carriers during surveillance, compared to the other genotypes.

Conclusions

We found that 35% of the CRC cases detected during surveillance were found after 24 months. MLH1 and MSH2 carriers were at higher risk of developing CRC during surveillance. Additionally, men, current or previous smokers, and patients with a higher BMI were at higher risk of developing CRC. Currently, LS patients are recommended a "one-size-fits-all" surveillance program. The results support the development of a risk-score whereby individual risk factors should be taken into consideration when deciding on an optimal surveillance interval.

What happens in the long term: Uptake of cancer surveillance and prevention strategies among at-risk relatives with pathogenic variants detected via cascade testing

BACKGROUND

Cascade genetic testing for hereditary cancer syndromes offers affected relatives the opportunity to pursue cancer screening and risk-reducing surgery and thus reduces morbidity and mortality. The purpose of this study was to measure the long-term utilization of targeted cancer prevention and quality of life among at-risk relatives offered clinician-facilitated cascade genetic testing.

METHODS

In a pilot study, at-risk relatives of patients with a hereditary cancer syndrome were contacted directly by the clinical team and offered telephone genetic counseling and genetic testing via an at-home, mailed saliva kit. Two-year follow-up results evaluating the use of targeted cancer prevention strategies and the quality of life for enrolled relatives were reported. Quality-of-life was measured with validated surveys, and scores were compared to the time of initial contact by the Wilcoxon signed-rank test.

RESULTS

Ninety-five at-risk relatives were enrolled in the initial pilot study, and 72 (76%) participated in the 2-year follow-up; 57 of these (79%) had completed genetic testing. Twenty-five of those 57 relatives (44%) were found to harbor an inherited pathogenic variant. Guideline-based cancer surveillance was recommended to 18 relatives; 13 (72%) completed at least one recommended screening, and six (33%) completed all recommended screenings. Risk-reducing surgery was recommended to 10 relatives; four (40%) completed a total of eight procedures. Quality-of-life surveys demonstrated low levels of anxiety, depression, distress, and uncertainty.

CONCLUSIONS

The 2-year follow-up of the original pilot study revealed that clinician-facilitated cascade testing resulted in genetically targeted cancer screening and prevention with preserved quality of life. These results, to be confirmed by larger randomized controlled trials, suggest that medical systems should consider supporting clinician-facilitated cascade testing programs.

Cascade Testing for Hereditary Cancer Syndromes: Should We Move Toward Direct Relative Contact? A Systematic Review and Meta-Analysis

PURPOSE

Evidence-based guidelines recommend cascade genetic counseling and testing for hereditary cancer syndromes, providing relatives the opportunity for early detection and prevention of cancer. The current standard is for patients to contact and encourage relatives (patient-mediated contact) to undergo counseling and testing. Direct relative contact by the medical team or testing laboratory has shown promise but is complicated by privacy laws and lack of infrastructure. We sought to compare outcomes associated with patient-mediated and direct relative contact for hereditary cancer cascade genetic counseling and testing in the first meta-analysis on this topic.

MATERIALS AND METHODS

We conducted a systematic review and meta-analysis in accordance with Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines (PROSPERO No.: CRD42020134276). We searched key electronic databases to identify studies evaluating hereditary cancer cascade testing. Eligible trials were subjected to meta-analysis.

RESULTS

Eighty-seven studies met inclusion criteria. Among relatives included in the meta-analysis, 48% (95% CI, 38 to 58) underwent cascade genetic counseling and 41% (95% CI, 34 to 48) cascade genetic testing. Compared with the patient-mediated approach, direct relative contact resulted in significantly higher uptake of genetic counseling for all relatives (63% [95% CI, 49 to 75] v 35% [95% CI, 24 to 48]) and genetic testing for first-degree relatives (62% [95% CI, 49 to 73] v 40% [95% CI, 32 to 48]). Methods of direct contact included telephone calls, letters, and e-mails; respective rates of genetic testing completion were 61% (95% CI, 51 to 70), 48% (95% CI, 37 to 59), and 48% (95% CI, 45 to 50).

CONCLUSION

Most relatives at risk for hereditary cancer do not undergo cascade genetic counseling and testing, forgoing potentially life-saving medical interventions. Compared with patient-mediated contact, direct relative contact increased rates of cascade genetic counseling and testing, arguing for a shift in the care delivery paradigm, to be confirmed by randomized controlled trials.

Strong Hereditary Predispositions to Colorectal Cancer

Cancer is one of the most common causes of death worldwide. A strong predisposition to cancer is generally only observed in colorectal cancer (5% of cases) and breast cancer (2% of cases). Colorectal cancer is the most common cancer with a strong genetic predisposition, but it includes dozens of various syndromes. This group includes familial adenomatous polyposis, attenuated familial adenomatous polyposis, MUTYH-associated polyposis, NTHL1-associated polyposis, Peutz-Jeghers syndrome, juvenile polyposis syndrome, Cowden syndrome, Lynch syndrome, and Muir-Torre syndrome. The common symptom of all these diseases is a very high risk of colorectal cancer, but depending on the condition, their course is different in terms of age and range of cancer occurrence. The rate of cancer development is determined by its conditioning genes, too. Hereditary predispositions to cancer of the intestine are a group of symptoms of heterogeneous diseases, and their proper diagnosis is crucial for the appropriate management of patients and their successful treatment. Mutations of specific genes cause strong colorectal cancer predispositions. Identifying mutations of predisposing genes will support proper diagnosis and application of appropriate screening programs to avoid malignant neoplasm.

The predicted effect and cost-effectiveness of tailoring colonoscopic surveillance according to mismatch repair gene in patients with Lynch syndrome

PURPOSE

Lynch syndrome-related colorectal cancer (CRC) risk substantially varies by mismatch repair (MMR) gene. We evaluated the health impact and cost-effectiveness of MMR gene-tailored colonoscopic surveillance.

METHODS

We first estimated sex- and MMR gene-specific cumulative lifetime risk of first CRC without colonoscopic surveillance using an optimization algorithm. Next, we harnessed these risk estimates in a microsimulation model, "Policy1-Lynch," and compared 126 colonoscopic surveillance strategies against no surveillance.

RESULTS

The most cost-effective strategy was 3-yearly surveillance from age 25 to 70 years (pathogenic variants [path_] in MLH1 [path_MLH1], path_MSH2) with delayed surveillance for path_MSH6 (age 30-70 years) and path_PMS2 (age 35-70 years) heterozygotes (incremental cost-effectiveness ratio = Australian dollars (A) $8,833/life-year saved). This strategy averted 60 CRC deaths (153 colonoscopies per death averted) over the lifetime of 1000 confirmed patients with Lynch syndrome (vs no surveillance). This also reduced colonoscopies by 5% without substantial change in health outcomes (vs nontailored 3-yearly surveillance from 25-70 years). Generally, starting surveillance at age 25 (vs 20) years was more cost-effective with minimal effect on life-years saved and starting 5 to 10 years later for path_MSH6 and path_PMS2 heterozygotes (vs path_MLH1 and path_MSH2) further improved cost-effectiveness. Surveillance end age (70/75/80 years) had a minor effect. Three-yearly surveillance strategies were more cost-effective (vs 1 or 2-yearly) but prevented 3 fewer CRC deaths.

CONCLUSION

MMR gene-specific colonoscopic surveillance would be effective and cost-effective.

OUP accepted manuscript

Background

We explored health professionals’ views on the utility of circulating tumor DNA (ctDNA) testing in hereditary cancer syndrome (HCS) management.

Materials and Methods

A qualitative interpretive description study was conducted, using semi-structured interviews with professionals across Canada. Thematic analysis employing constant comparison was used for analysis. 2 investigators coded each transcript. Differences were reconciled through discussion and the codebook was modified as new codes and themes emerged from the data.

Results

Thirty-five professionals participated and included genetic counselors (n = 12), geneticists (n = 9), oncologists (n = 4), family doctors (n = 3), lab directors and scientists (n = 3), a health-system decision maker, a surgeon, a pathologist, and a nurse. Professionals described ctDNA as “transformative” and a “game-changer”. However, they were divided on its use in HCS management, with some being optimistic (optimists) while others were hesitant (pessimists). Differences were driven by views on 3 factors: (1) clinical utility, (2) ctDNA’s role in cancer screening, and (3) ctDNA’s invasiveness. Optimists anticipated ctDNA testing would have clinical utility for HCS patients, its role would be akin to a diagnostic test and would be less invasive than standard screening (eg imaging). Pessimistic participants felt ctDNA testing would add limited utility; it would effectively be another screening test in the pathway, likely triggering additional investigations downstream, thereby increasing invasiveness.

Conclusions

Providers anticipated ctDNA testing will transform early cancer detection for HCS families. However, the contrasting positions on ctDNA’s role in the care pathway raise potential practice variations, highlighting a need to develop evidence to support clinical implementation and guidelines to standardize adoption.

Interval between the First Cancer and the Genetic Diagnosis in Lynch Syndrome Probands

Objective Little is known about the time from developing a first cancer to confirming the presence of a mismatch repair (MMR) gene mutation for Lynch syndrome (LS) probands. Methods This was a retrospective single center study. LS probands, who have an MMR gene mutation that was confirmed first in a pedigree and thereafter developed at least one cancer, were included in this study. Results There were 21 LS probands who had developed at least one cancer; 6 with MLH1 mutations, 9 with MSH2 mutations, 4 with MSH6 mutations, and 2 with EPCAM deletions. The median ages at the first cancer and the genetic diagnosis were 47 (34-71) and 62 (38-84) years old, respectively. The mean interval between the first cancer and the genetic diagnosis was 11.0 (0-25) years, and 20 years or longer interval was required for the 5 probands. Six (28.6%) probands were older than 70 years, and 3 (14.3%) were in their 80s when they were diagnosed to have LS. The genetic diagnosis was confirmed at the first, second, third, and fourth cancer or later in 5, 5, 6, and 5 probands, respectively. Of the 16 cancers examined, 2 (12.5%) were microsatellite stable (MSS), both of whom had germline MSH6 mutations. All 17 LS probands who developed colorectal cancer met the revised Bethesda guidelines at the genetic diagnosis, but only 7 of 11 (63.6%) met them at the first cancer. Twelve out of 21 (57.1%) met the revised Amsterdam criteria. Conclusion It took 11 years for the LS probands from the first cancer to the diagnostic confirmation by genetic tests. A quarter of the probands were in their 70s or 80s at genetic diagnosis.

Japanese Society for Cancer of the Colon and Rectum (JSCCR) guidelines 2020 for the Clinical Practice of Hereditary Colorectal Cancer

Hereditary colorectal cancer (HCRC) accounts for < 5% of all colorectal cancer cases. Some of the unique characteristics commonly encountered in HCRC cases include early age of onset, synchronous/metachronous cancer occurrence, and multiple cancers in other organs. These characteristics necessitate different management approaches, including diagnosis, treatment or surveillance, from sporadic colorectal cancer management. There are two representative HCRC, named familial adenomatous polyposis and Lynch syndrome. Other than these two HCRC syndromes, related disorders have also been reported. Several guidelines for hereditary disorders have already been published worldwide. In Japan, the first guideline for HCRC was prepared by the Japanese Society for Cancer of the Colon and Rectum (JSCCR), published in 2012 and revised in 2016. This revised version of the guideline was immediately translated into English and published in 2017. Since then, several new findings and novel disease concepts related to HCRC have been discovered. The currently diagnosed HCRC rate in daily clinical practice is relatively low; however, this is predicted to increase in the era of cancer genomic medicine, with the advancement of cancer multi-gene panel testing or whole genome testing, among others. Under these circumstances, the JSCCR guidelines 2020 for HCRC were prepared by consensus among members of the JSCCR HCRC Guideline Committee, based on a careful review of the evidence retrieved from literature searches, and considering the medical health insurance system and actual clinical practice settings in Japan. Herein, we present the English version of the JSCCR guidelines 2020 for HCRC.

Distinct Mutational Profile of Lynch Syndrome Colorectal Cancers Diagnosed under Regular Colonoscopy Surveillance

Regular colonoscopy even with short intervals does not prevent all colorectal cancers (CRC) in Lynch syndrome (LS). In the present study, we asked whether cancers detected under regular colonoscopy surveillance (incident cancers) are phenotypically different from cancers detected at first colonoscopy (prevalent cancers). We analyzed clinical, histological, immunological and mutational characteristics, including panel sequencing and high-throughput coding microsatellite (cMS) analysis, in 28 incident and 67 prevalent LS CRCs (n total = 95). Incident cancers presented with lower UICC and T stage compared to prevalent cancers (p < 0.0005). The majority of incident cancers (21/28) were detected after previous colonoscopy without any pathological findings. On the molecular level, incident cancers presented with a significantly lower KRAS codon 12/13 (1/23, 4.3% vs. 11/21, 52%; p = 0.0005) and pathogenic TP53 mutation frequency (0/17, 0% vs. 7/21, 33.3%; p = 0.0108,) compared to prevalent cancers; 10/17 (58.8%) incident cancers harbored one or more truncating APC mutations, all showing mutational signatures of mismatch repair (MMR) deficiency. The proportion of MMR deficiency-related mutational events was significantly higher in incident compared to prevalent CRC (p = 0.018). In conclusion, our study identifies a set of features indicative of biological differences between incident and prevalent cancers in LS, which should further be monitored in prospective LS screening studies to guide towards optimized prevention protocols.

Colorectal cancer screening in Lynch syndrome: Indication, techniques and future perspectives

Lynch syndrome (LS) is an inherited predisposition to colorectal cancer (CRC), responsible for 3-5% of all CRC. This syndrome is characterized by the early occurrence of colorectal neoplastic lesions, with variable incidences depending on the type of pathogenic variants in MMR genes (MLH1, MSH2, MSH6, PMS2 and EPCAM) and demographics factors such as gender, body mass index, tobacco use and physical activity. Similar to sporadic cancers, colorectal screening by colonoscopy is efficient because it is associated with a reduction >50% of both CRC incidence and CRC related mortality. To that end, most guidelines recommend high definition screening colonoscopies in dedicated centers, starting at the age of 20-25 years old, with a surveillance interval of 1-2 years. In this review, we discuss the importance of high definition colonoscopies, including the compliance to specific key performance indicators, as well as the expected benefits of specific imaging modalities including virtual chromoendoscopy and dye-spray chromoendoscopy.

Historical review of Lynch syndrome

Lynch syndrome was formerly known as Hereditary Nonpolyposis Colorectal Cancer. Currently, these two nomenclatures each have their unique definitions and are no longer used interchangeably. The history of hereditary nonpolyposis colorectal cancer was first recognized formally in the literature by Henry Lynch in 1967. With advances of molecular genetics, there has been a transformation from clinical phenotype to genotype diagnostics. This has led to the ability to diagnose affected patients before they manifest with cancer, and therefore allow preventative surveillance strategies. Genotype diagnostics has shown a difference in penetrance of different cancer risks dependent on the gene containing the mutation. Surgery is recommended as prevention for some cancers; for others they are reserved for once cancer is noted. Various surveillance strategies are recommended dependent on the relative risk of cancer and the ability to intervene with surgery to impact on survival. Risk reduction through aspirin has shown some recent promise, and continues to be studied.

The "unnatural" history of colorectal cancer in Lynch syndrome: Lessons from colonoscopy surveillance

Individuals with Lynch syndrome (LS), one of the most common inherited cancer syndromes, are at increased risk of developing malignancies, in particular colorectal cancer (CRC). Regular colonoscopy with polypectomy is recommended to reduce CRC risk in LS individuals. However, recent independent studies demonstrated that a substantial proportion of LS individuals develop CRC despite regular colonoscopy. The reasons for this surprising observation confirmed by large prospective studies are a matter of debate. In this review, we collect existing evidence from clinical, epidemiological and molecular studies and interpret them with regard to the origins and progression of LS-associated CRC. Alongside with hypotheses addressing colonoscopy quality and pace of progression from adenoma to cancer, we discuss the role of alternative precursors and immune system in LS-associated CRC. We also identify gaps in current knowledge and make suggestions for future studies aiming at improved CRC prevention for LS individuals.

Progress Report: New insights into the prevention of CRC by colonoscopic surveillance in Lynch syndrome

Lynch syndrome is the most frequent hereditary colorectal cancer (CRC) syndrome, affecting approximately 1 in 300 in the Western population. It is caused by pathogenic variants in the mismatch repair (MMR) genes including MLH1, MSH2 (EPCAM), MSH6 and PMS2, and is associated with high risks of CRC, endometrial cancer and other cancers. In view of these risks, carriers of such variants are encouraged to participate in colonoscopic surveillance programs that are known to substantially improve their prognosis. In the last decade several important studies have been published that provide detailed cancer risk estimates and prognoses based on large numbers of patients. These studies also provided new insights regarding the pathways of carcinogenesis in CRC, which appear to differ depending on the specific MMR gene defect. In this report, we will discuss the implications of these new findings for the development of new surveillance protocols.

Precision Prevention: The Current State and Future of Genomically Guided Cancer Prevention

The identification of cancer-predisposing germline variants has potentially substantial clinical impact for patients and their families. Although management guidelines have been proposed for some genes, guidelines for other genes are lacking. This review focuses on the current surveillance and management guidelines for the most common hereditary cancer syndromes and discusses some of the most pivotal studies supporting the available guidelines. We also highlight the gaps in the identification of germline carriers, the cascade testing of at-risk relatives, and the challenges impeding the proper follow-up and optimal management of pathogenic germline carriers. The anticipated surge in the number of identified germline carriers, deficient management guidelines, poor cascade testing uptake, and long-term follow-up necessitate the development of multidisciplinary clinics as an obligatory step toward the improvement of cancer prevention.

Value of upper gastrointestinal endoscopy for gastric cancer surveillance in patients with Lynch syndrome

In our study, we evaluated the effectiveness of upper gastrointestinal (GI) endoscopy as an instrument for early gastric cancer (GC) detection in Lynch syndrome (LS) patients by analyzing data from the registry of the German Consortium for Familial Intestinal Cancer. In a prospective, multicenter cohort study, 1128 out of 2009 registered individuals with confirmed LS underwent 5176 upper GI endoscopies. Compliance was good since 77.6% of upper GI endoscopies were completed within the recommended interval of 1 to 3 years. Forty-nine GC events were observed in 47 patients. MLH1 (n = 21) and MSH2 (n = 24) mutations were the most prevalent. GCs in patients undergoing regular surveillance were diagnosed significantly more often in an early-stage disease (UICC I) than GCs detected through symptoms (83% vs 25%; P = .0231). Thirty-two (68%) patients had a negative family history of GC. The median age at diagnosis was 51 years (range 28-66). Of all GC patients, 13 were diagnosed at an age younger than 45. Our study supports the recommendation of regular upper GI endoscopy surveillance for LS patients beginning no later than at the age of 30.

Cost-effectiveness analysis of genetic diagnostic strategies for Lynch syndrome in Italy

Lynch syndrome (LS) is an autosomal dominant condition caused by pathogenic variants in mismatch repair (MMR) genes that predispose individuals to different malignancies, such as colorectal cancer (CRC) and endometrial cancer. Current guidelines recommended testing for LS in individuals with newly diagnosed CRC to reduce cancer morbidity and mortality in relatives. Economic evaluations in support of such approach, however, are not available in Italy. We developed a decision-analytic model to analyze the cost-effectiveness of LS screening from the perspective of the Italian National Health System. Three testing strategies: the sequencing of all MMR genes without prior tumor analysis (Strategy 1), a sequential IHC and MS-MLPA analysis (Strategy 2), and an age-targeted strategy with a revised Bethesda criteria assessment before IHC and methylation-specific MLPA for patients ≥ than 70 years old (Strategy 3) were analyzed and compared to the “no testing” strategy. Quality Adjusted Life Years (QALYs) in relatives after colonoscopy, aspirin prophylaxis and an intensive gynecological surveillance were estimated through a Markov model. Assuming a CRC incidence rate of 0.09% and a share of patients affected by LS equal to 2.81%, the number of detected pathogenic variants among CRC cases ranges, in a given year, between 910 and 1167 depending on the testing strategy employed. The testing strategies investigated, provided one-time to the entire eligible population (CRC patients), were associated with an overall cost ranging between €1,753,059.93-€10,388,000.00. The incremental cost-effectiveness ratios of the Markov model ranged from €941.24 /QALY to €1,681.93 /QALY, thus supporting that “universal testing” versus “no testing” is cost-effective, but not necessarily in comparison with age-targeted strategies. This is the first economic evaluation on different testing strategies for LS in Italy. The results might support the introduction of cost-effective recommendations for LS screening in Italy.

Adequacy evaluation of the annual colonoscopic surveillance and individual difference of disease phenotypes in Lynch syndrome

BACKGROUND

Regular endoscopic surveillance for Lynch syndrome is reported to reduce colorectal cancer (CRC)-related mortality. However, the appropriate surveillance intervals are still unclear. We evaluated the adequacy of annual colonoscopy and investigated the differences in tumor occurrence rates between individual patients.

METHODS

In total, 25 patients with Lynch syndrome who underwent colonoscopic surveillance between 2007 and 2016 at the Iwakuni Clinical Center were included. We retrospectively investigated the surveillance frequency and the clinical features associated with tumor development.

RESULTS

Colonoscopic surveillance was performed every 397 days on average. A total of 101 tumors, including 8 intramucosal carcinomas and 15 carcinomas, were observed within the study period. Annual colonoscopy detected six malignancies, including a carcinoma requiring surgery. Tumor incidence was associated with tumor existence in the initial colonoscopies (P = 0.018). Patients with a tumor occurrence rate of 0.4 tumors per year during our observation period were significantly more likely to have malignancies detected during regular surveillance than patients who had a lower occurrence rate (P < 0.001). Malignancy occurrence rate was strongly associated with tumor occurrence rate (P < 0.001, R2 = 0.44).

CONCLUSIONS

Annual colonoscopic surveillance for Lynch syndrome patients was effective in reducing the risk of CRC progression, but was insufficient to completely avoid surgery. Because the tumor occurrence rate differed substantially between individuals, more intensive surveillance was required for high-risk patients.

Cancer risks in Lynch syndrome, Lynch-like syndrome, and familial colorectal cancer type X: a prospective cohort study

Background

Individuals with pathogenic germline variants in DNA mismatch repair (MMR) genes are at increased risk of developing colorectal, endometrial and other cancers (Lynch syndrome, LS). While previous studies have extensively described cancer risks in LS, cancer risks in individuals from families without detectable MMR gene defects despite MMR deficiency (Lynch-like syndrome, LLS), and in individuals from families fulfilling the Amsterdam-II criteria without any signs of MMR deficiency (familial colorectal cancer type X, FCCX) are less well studied. The aim of this prospective study was to characterise the risk for different cancer types in LS, LLS, and FCCX, and to compare these with the cancer risks in the general population.

Methods

Data was taken from the registry of the German Consortium for Familial Intestinal Cancer, where individuals were followed up prospectively within the framework of an intensified surveillance programme at recommended annual examination intervals. A total of 1120 LS, 594 LLS, and 116 FCCX individuals were analysed. From this total sample, eight different cohorts were defined, in which age-dependent cumulative risks and standardised incidence ratios were calculated regarding the first incident occurrence of any, colorectal, stomach, small bowel, urothelial, female breast, ovarian, and endometrial cancer, separately for LS, LLS, and FCCX.

Results

The number of individuals at risk for first incident cancer ranged from 322 to 1102 in LS, 120 to 586 in LLS, and 40 to 116 in FCCX, depending on the cancer type of interest. For most cancer types, higher risks were observed in LS compared to LLS, FCCX, and the general population. Risks for any, colorectal, stomach, urothelial, and endometrial cancer were significantly higher in LLS compared to the general population. No significantly increased risks could be detected in FCCX compared to LLS patients, and the general population. Colorectal and endometrial cancer risks tended to be higher in LLS than in FCCX.

Conclusions

The characterisation of cancer risks in patients with LLS and FCCX is important to develop appropriate surveillance programmes for these specific intermediate risk groups. Larger prospective studies are needed to obtain more precise risk estimates.

Associations of Pathogenic Variants in MLH1, MSH2, and MSH6 With Risk of Colorectal Adenomas and Tumors and With Somatic Mutations in Patients With Lynch Syndrome

BACKGROUND & AIMS

Lynch syndrome is caused by variants in DNA mismatch repair (MMR) genes and associated with an increased risk of colorectal cancer (CRC). In patients with Lynch syndrome, CRCs can develop via different pathways. We studied associations between Lynch syndrome-associated variants in MMR genes and risks of adenoma and CRC and somatic mutations in APC and CTNNB1 in tumors in an international cohort of patients.

METHODS

We combined clinical and molecular data from 3 studies. We obtained clinical data from 2747 patients with Lynch syndrome associated with variants in MLH1, MSH2, or MSH6 from Germany, the Netherlands, and Finland who received at least 2 surveillance colonoscopies and were followed for a median time of 7.8 years for development of adenomas or CRC. We performed DNA sequence analyses of 48 colorectal tumors (from 16 patients with mutations in MLH1, 29 patients with mutations in MSH2, and 3 with mutations in MSH6) for somatic mutations in APC and CTNNB1.

RESULTS

Risk of advanced adenoma in 10 years was 17.8% in patients with pathogenic variants in MSH2 vs 7.7% in MLH1 (P < .001). Higher proportions of patients with pathogenic variants in MLH1 or MSH2 developed CRC in 10 years (11.3% and 11.4%) than patients with pathogenic variants in MSH6 (4.7%) (P = .001 and P = .003 for MLH1 and MSH2 vs MSH6, respectively). Somatic mutations in APC were found in 75% of tumors from patients with pathogenic variants in MSH2 vs 11% in MLH1 (P = .015). Somatic mutations in CTNNB1 were found in 50% of tumors from patients with pathogenic variants in MLH1 vs 7% in MSH2 (P = .002). None of the 3 tumors with pathogenic variants in MSH6 had a mutation in CTNNB1, but all had mutations in APC.

CONCLUSIONS

In an analysis of clinical and DNA sequence data from patients with Lynch syndrome from 3 countries, we associated pathogenic variants in MMR genes with risk of adenoma and CRC, and somatic mutations in APC and CTNNB1 in colorectal tumors. If these findings are confirmed, surveillance guidelines might be adjusted based on MMR gene variants.

Variation in Blood and Colorectal Epithelia's Key Trace Elements Along with Expression of Mismatch Repair Proteins from Localized and Metastatic Colorectal Cancer Patients

Colorectal cancer (CRC) is an increasingly common medical issue affecting millions worldwide, and contribution of the body's trace elements to CRC is arguable. The concentrations and buffered status of selenium, iron, copper, zinc, and phosphorus in blood and large intestinal tissues of CRC patients are, respectively, variable and vital for cell physiology. The aim of this study was to assess selenium, iron, copper, zinc, and phosphorus variations in blood and colorectal epithelia along with examining the expression of mismatch repair proteins in CRC patients with/without metastasis for potential diagnosis/therapy. Concentrations of selenium, iron, copper, zinc, and phosphorus in blood of healthy versus CRC patients and colorectal epithelia (adenocarcinomatous versus non-adenocarcinomatous/control) were measured in 40 CRC patients (55.87 ± 11.9 years old) with/without metastasis before surgery using ICP-OES. Mismatch repair (MMR) protein expression was analyzed through histopathological/immunohistochemistry assays, which was sparse in 5 CRC patient's colorectal tissues (12%). Compared with healthy individuals, blood and colorectal tissue's levels of phosphorus, copper, and iron were significantly higher in the CRC patients, and more pronounced in metastatic CRC patients; conversely, blood and colorectal tissue's selenium levels were significantly lower in metastatic patients. Unlike blood zinc, cancerous colorectal tissue's zinc concentration was significantly lower in CRC patients compared to healthy control cohorts. There was no significant difference on the measured elements in samples from CRC patients with MMR^- compared to CRC patients with MMR⁺. Receiver operating characteristic analysis revealed a correlation of blood iron, zinc, copper, and phosphorus to CRC, and inappropriately low levels of blood and colorectal selenium correlated with exacerbated metastasis. Altered levels of selenium, iron, copper, zinc, and phosphorus in vivo may impact the pathogenesis and detection of CRC, and their diagnostic/therapeutic potential in CRC would be revealing.

Use of Family History and Genetic Testing to Determine Risk of Colorectal Cancer

Approximately 35% of patients with colorectal cancer (CRC) have a family history of the disease attributed to genetic factors, common exposures, or both. Some families with a history of CRC carry genetic variants that cause CRC with high or moderate penetrance, but these account for only 5% to 10% of CRC cases. Most families with a history of CRC and/or adenomas do not carry genetic variants associated with cancer syndromes; this is called common familial CRC. Our understanding of familial predisposition to CRC and cancer syndromes has increased rapidly due to advances in next-generation sequencing technologies. As a result, there has been a shift from genetic testing for specific inherited cancer syndromes based on clinical criteria alone, to simultaneous testing of multiple genes for cancer-associated variants. We summarize current knowledge of common familial CRC, provide an update on syndromes associated with CRC (including the nonpolyposis and polyposis types), and review current recommendations for CRC screening and surveillance. We also provide an approach to genetic evaluation and testing in clinical practice. Determination of CRC risk based on family cancer history and results of genetic testing can provide a personalized approach to cancer screening and prevention, with optimal use of colonoscopy to effectively decrease CRC incidence and mortality.

Immunohistochemistry in screening for heritable colorectal cancer: what to do with an abnormal result

Recent developments in our understanding of molecular genetics have transformed screening and diagnostic practices for Lynch syndrome. The current standard involves universal tumour analysis of resected colorectal cancer (and ideally polypectomy) specimens using immunohistochemistry and molecular techniques. Patients with abnormal immunohistochemical findings are subsequently referred for definitive mutational testing. This review relates the molecular pathogenesis of Lynch syndrome to current immunohistochemistry-based screening strategies and discusses the interpretation and clinical implications of screening results.

Prophylactic Surgery and Extended Oncologic Radicality in Gastric and Colorectal Hereditary Cancer Syndromes

Prophylactic surgery for high-penetrance hereditary gastric and colorectal cancer can be a primary prophylaxis of cancer and a secondary oncologic prevention. As early cancer is often detected in the resected organ, there has been no prophylaxis of cancer but cancer treatment. Extended oncological radicality with removal of the complete organ is a tertiary prevention as metachronous cancer is avoided. The indication for prophylactic surgery or extended oncological radicality is presented regarding hereditary and familial gastric and colorectal cancer. Hereditary diffuse type gastric cancer (E-cadherin mutation) and familial adenomatous polyposis coli (APC or MYH mutation) are well-accepted indications for prophylactic surgery with a variety of considerations regarding phenotype, genotype, associated diseases, age, timing, extent, and technique of surgery. Not so much prophylactic surgery as extended oncologic radicality can be considered in familial gastric and colorectal cancer as well as Lynch or hereditary nonpolyposis colorectal cancer syndrome (HNPCC). Clinical, molecular, and technical progress leads to less invasive and risk-adapted surgical and nonsurgical interventions, expanding the variety of individualized treatment options.

Genetic Counseling and Surveillance Focused on Lynch Syndrome

Lynch syndrome is a hereditary cancer syndrome caused by germline mutations in one of several DNA mismatch repair genes. Lynch syndrome leads to an increased lifetime risk of various cancers, particularly colorectal, and endometrial cancers. After identifying patients suspected of having Lynch syndrome by clinical criteria, computational prediction models, and/or universal tumor testing, genetic testing is performed to confirm the diagnosis. Before and after genetic testing, genetic counseling should be provided. Genetic counseling should involve a detailed personal and family history, information on the disorder and genetic tests, discussion of the management and surveillance of the disease, career plan, family plan, and psychosocial support. Surveillance of colorectal cancer and other malignancies is of paramount importance for properly managing Lynch syndrome. This review focuses on important considerations in genetic counseling and the latest insights into the surveillance of individuals and families with Lynch syndrome.

For Women, Lynch Syndrome Is About More than Colon Cancer

Lynch syndrome, also known as hereditary nonpolyposis colorectal cancer, has historically been characterized by a predisposition to colorectal cancer; however, for women with Lynch syndrome, the risks for gynecologic cancers pose an equal or greater risk than colorectal cancer. In addition, the gynecologic cancer is often the first cancer that presents in these patients. Also of importance to women with Lynch syndrome is the efficacy of gynecologic cancer screening being significantly lower than colorectal cancer screening, leading to inconsistency in provider recommendations for gynecologic screening and surveillance. We had the chance to listen to women with Lynch syndrome, in their own words, discuss their health care experiences as they relate to gynecologic cancer risk, and identified several important themes. They describe feeling confused about their screening and surveillance options while also being heavily reliant on their health care providers for guidance. In addition, women with Lynch syndrome discuss attempting to balance medical management of Lynch syndrome with their reproductive choices. Finally, they believe that increased awareness by women and their providers about the gynecologic cancer risks associated with Lynch syndrome should be a higher priority. We view the words of these women as a call to action for Lynch syndrome patients, clinicians, researchers, and advocates.

Lethal privacy: Quantifying life years lost if the right to informational self-determination guides genetic screening for Lynch syndrome

Genetic relatives of hereditary colorectal cancer patients with Lynch syndrome (LS) are at risk of cancer. Testing both colorectal cancer patients and relatives of mutation carriers for LS allows targeted prevention. However, this could mean disclosing sensitive health data to family members. In light of potential trade-offs between cost-effectiveness and patient privacy, this study investigates the implications of increasing test uptake in Germany. Out of 22 screening strategies for LS, the non-dominated and current German strategies were assessed from the perspective of the statutory health insurance. Life years gained by increased prevention were estimated with Markov models. The effects and implications of different test uptake rates in index patients and their relatives were investigated by scenario analysis. Privacy limitations could yield health gains of up to 2500 undiscounted life years for first-degree relatives of index patients and substantially improve cost-effectiveness. However, this approach may contradict the right to informational self-determination. This study demonstrates the effect higher LS test uptakes could have on the lives and rights of colorectal cancer patients and their relatives. It shows potential conflicts between the efficient use of health care resources on the one hand and reasonable consideration of patient autonomy on the other.

Case report of synchronous post-lung transplant colon cancers in the era of colorectal cancer screening recommendations in cystic fibrosis: screening "too early" before it's too late

BACKGROUND

The increasing life expectancy of individuals with Cystic Fibrosis (CF) is likely to be associated with new age-related challenges, colorectal cancer (CRC) most notably; recent consensus recommendations for CRC screening published in 2018 represent an important early step in addressing the emerging awareness of CF as a gastrointestinal cancer syndrome. These recommendations, however, need to be further refined based on more systematic data. We discuss an illustrative first-ever case of synchronous CRC arising in a post-lung transplant individual with CF within the recommended surveillance interval after a well-documented prior normal colonoscopy.

CASE PRESENTATION

A 51-year-old female individual with homozygous F508del CF, presents to clinic with abdominal discomfort and intermittent blood in stools. She had previously undergone bilateral lung transplantation 18 years earlier, as well as two kidney transplants related to immunosuppression-related nephrotoxicity. A diagnostic colonoscopy was performed which revealed the presence of two separate synchronous colon cancers in the cecum and transverse colon; she had undergone a colonoscopy three years prior to this exam which was structurally normal. Endoscopic quality indicators, including a good quality bowel preparation, colonoscopic withdrawal time > 12 min, and quarterly Adenoma Detection Rate (ADR) ranging from 50 to 70% for both male and female patients for the endoscopist from both colonoscopic exams, as well as secondary retrospective comparative review of the pertinent case images, diminish the risk for a "missed" cancer or advanced lesion on the index exam. These cancers did not demonstrate any immunohistochemical features suggestive of Lynch Syndrome, though the rapid progression to cancer within the surveillance interval (possibly non-polypoid in nature) is similar. This cancer presentation within the newly-established recommended colon cancer screening interval warrants concern.

CONCLUSIONS

This case prompts serious discussion regarding the length of surveillance intervals in the post-transplant CF population (a population at 20-30 times greater risk for CRC compared to the general non-CF population), as well as the importance of documenting endoscopic quality benchmarks, particularly if a narrative of interval CRC development continues to develop with further prospective monitoring and multi-center experience.

Malignant phyllodes tumor in Lynch syndrome: a case report

BACKGROUND

Lynch syndrome, or hereditary nonpolyposis colorectal cancer, is an autosomal dominant genetic syndrome that predisposes individuals to multiple cancer types. The known cancers associated with Lynch syndrome include colorectal and endometrial cancers as well as cancers of the stomach, ovary, urinary tract, hepatobiliary tract, pancreas, small bowel, and brain. There are no searchable cases of malignant phyllodes of the breast associated with Lynch syndrome.

CASE PRESENTATION

Our patient was a 43-year-old Caucasian woman who felt a lump in her left breast and was found to have a spindle cell neoplasm. Definitive surgery revealed a malignant phyllodes tumor. On the basis of her cancer diagnosis and family history of multiple cancers, a Myriad myRisk Hereditary Cancer® test panel of 25 genes was performed. This testing revealed that she had a heterozygous MSH6 mutation as part of the Lynch syndrome panel. Due to positive margins, the patient received adjuvant chemotherapy with doxorubicin and ifosfamide. She also had a subsequent total abdominal hysterectomy and a bilateral salpingo-oophorectomy for risk reduction. She remains in a high-risk surveillance program. Her family members have been tested, which revealed that her two brothers and daughter also carry the genetic mutation.

CONCLUSIONS

This case highlights the importance of genetic testing with rare malignancies because the full scope of phenotypic sequelae for known hereditary syndromes has not been mapped.

5-Hydroxymethylcytosine as a clinical biomarker: Fluorescence-based assay for high-throughput epigenetic quantification in human tissues

Epigenetic transformations may provide early indicators for cancer and other disease. Specifically, the amount of genomic 5-hydroxymethylcytosine (5-hmC) was shown to be globally reduced in a wide range of cancers. The integration of this global biomarker into diagnostic workflows is hampered by the limitations of current 5-hmC quantification methods. Here we present and validate a fluorescence-based platform for high-throughput and cost-effective quantification of global genomic 5-hmC levels. We utilized the assay to characterize cancerous tissues based on their 5-hmC content, and observed a pronounced reduction in 5-hmC level in various cancer types. We present data for glioblastoma, colorectal cancer, multiple myeloma, chronic lymphocytic leukemia and pancreatic cancer, compared to corresponding controls. Potentially, the technique could also be used to follow response to treatment for personalized treatment selection. We present initial proof-of-concept data for treatment of familial adenomatous polyposis.

Translating genomic risk into an early detection strategy for sarcoma

Sarcomas have a strong genetic etiology, and the study of families affected by sarcomas has informed much of what we now understand of modern cancer biology. The recent emergence of powerful genetic technologies has led to astonishing reductions in costs and increased throughput. In the clinic, these technologies are revealing a previously unappreciated and rich landscape of genetic cancer risk. In addition to both known and new cancer risk mutations, genomic tools are cataloguing complex and polygenic risk patterns, collectively explaining between 15-25% of apparently sporadic sarcoma cases. The impact on clinical management is exemplified by Li-Fraumeni Syndrome, the most penetrant sarcoma syndrome. Whole body magnetic resonance imaging can identify surgically resectable cancers in up to one in ten individuals with Li-Fraumeni Syndrome. Taken together, parallel developments in genomics, therapeutics and imaging technologies will drive closer engagement between genetics and multidisciplinary care of the sarcoma patient in the 21st century.

No Difference in Colorectal Cancer Incidence or Stage at Detection by Colonoscopy Among 3 Countries With Different Lynch Syndrome Surveillance Policies

BACKGROUND & AIMS

Patients with Lynch syndrome are at high risk for developing colorectal cancer (CRC). Regular colonoscopic surveillance is recommended, but there is no international consensus on the appropriate interval. We investigated whether shorter intervals are associated with lower CRC incidence and detection at earlier stages by comparing the surveillance policies in Germany, which evaluates patients by colonoscopy annually, in the Netherlands (patients evaluated at 1-2-year intervals), and Finland (patients evaluated at 2-3-year intervals).

METHODS

We collected data from 16,327 colonoscopic examinations (conducted from 1984 through 2015) of 2747 patients with Lynch syndrome (pathogenic variants in the MLH1, MSH2, or MSH6 genes) from the German HNPCC Consortium, the Dutch Lynch Syndrome Registry, and the Finnish Lynch Syndrome Registry. Our analysis included 23,309 person-years of cumulative observation time. Time from the index colonoscopy to incident CRC or adenoma was analyzed using the Kaplan-Meier method; groups were compared using the log-rank test. We performed multivariable Cox regression analyses to identify factors associated with CRC risk (diagnosis of CRC before the index colonoscopy, sex, mutation, age, and presence of adenoma at the index colonoscopy).

RESULTS

The 10-year cumulative CRC incidence ranged from 4.1% to 18.4% in patients with low- and high-risk profiles, respectively, and varied with age, sex, mutation, and prior detection of CRC or adenoma. Observed colonoscopy intervals were largely in accordance with the country-specific recommendations. We found no significant differences in cumulative CRC incidence or CRC stage at detection among countries. There was no significant association between CRC stage and time since last colonoscopy.

CONCLUSIONS

We did not find a significant reduction in CRC incidence or stage of detection in Germany (annual colonoscopic surveillance) than in countries with longer surveillance intervals (the Netherlands, with 1-2-year intervals, and Finland, with 2-3-year intervals). Overall, we did not find a significant association of the interval with CRC risk, although age, sex, mutation, and prior neoplasia were used to individually modify colonoscopy intervals. Studies are needed to develop and validate risk-adapted surveillance strategies and to identify patients who benefit from shorter surveillance intervals.

Screening and surveillance in hereditary gastrointestinal cancers: Recommendations from the European Society of Digestive Oncology (ESDO) expert discussion at the 20th European Society for Medical Oncology (ESMO)/World Congress on Gastrointestinal Cancer, Barcelona, June 2018

Patients with hereditary gastrointestinal (GI) cancers represent a substantial fraction of the overall affected population. Although awareness for hereditary GI cancer syndromes is on the rise, identification of patients and measures of surveillance are often unclear in everyday clinical routine. Therefore, the European Society of Digestive Oncology expert discussion 2018 at the World Congress on Gastrointestinal Cancer focussed on screening and surveillance of hereditary colorectal, gastric and pancreatic cancers. An international panel of experts and opinion leaders developed the here presented recommendations based on published evidence and on profound clinical expertise to facilitate clinical routine in identification and caretaking of patients with familial GI cancers.

Features of incident colorectal cancer in Lynch syndrome

Background and objective

Despite intensive colonoscopic surveillance, a substantial proportion of Lynch syndrome (LS) patients develop colorectal cancer (CRC). The aim of this study was to characterize incident CRC in LS patients.

Methods

All patients diagnosed with incident CRC after start of colonoscopic surveillance were identified in the Dutch LS Registry of 905 patients. A retrospective analysis of patient records was carried out for patient characteristics, survival, CRC characteristics and findings of previous colonoscopy.

Results

Seventy-one patients (7.8%) were diagnosed with incident CRC. Median interval between incident CRC diagnosis and previous colonoscopy was 23.8 (range 6.7-45.6) months. Median tumor diameter was 2.5 cm, and 17% of the tumors were sessile or flat. Most patients (83%) had no lymph node metastases. There was no association between tumor size and colonoscopy interval or lymph node status. Most patients (65%) had no adenomas during previous colonoscopy. Two patients (2.8%) eventually died from metastatic CRC.

Conclusion

The high frequency of incident CRC in LS likely results from several factors. Our findings lend support to the hypothesis of fast conversion of adenomas to CRC, as 65% of patients had no report of polyps during previous colonoscopy. High-quality colonoscopies are essential, especially as tumors and adenomas are difficult to detect because of their frequent non-polypoid appearance. Early detection due to surveillance as well as the indolent growth of CRC, as demonstrated by the lack of lymph node metastases, contributes to the excellent survival observed.

Colorectal cancer surveillance in Portuguese families with lynch syndrome: a cohort study

PURPOSE

Lynch syndrome (LS) is associated with a high risk of colorectal cancer (CRC). The aim of this study was to assess the cumulative risk for the development of colorectal adenomas or carcinomas in a LS CRC surveillance program and to audit the quality of the endoscopic procedures.

METHODS

We evaluated 147 asymptomatic LS mutation carriers, without previous CRC, in a surveillance program with colonoscopy every 12-18 months, between 2005 and 2016. Data was obtained by retrospective review of colonoscopy reports and hospital clinical files. The main outcome was assessed using Kaplan-Meier curves. Logistic regression was used to study the risk of developing adenomas.

RESULTS

Patients were under surveillance for 1092 observation years (mean, 7.7 years/patient). Most exams presented adequate bowel preparation (83.5%) and 99.2% achieved cecal intubation. The estimated risk for adenomas at age 60 was 75.6% in men (95%CI, 60.5-88.3) and 65.5% in women (95%CI, 50.8-79.7). Male gender (OR 2.4; 95%CI, 1.2-4.9; p = 0.018) and age at start of surveillance > 40 years (OR 3.7; 95%CI, 1.8-7.7; p < 0.001) were independent risk factors for adenoma detection. CRC was diagnosed in 11 patients with an estimated cumulative risk at age 60 of 18.4% (95%CI, 9.2-34.8%); 72.7% of CRC were classified as stage I; no patient died from CRC.

CONCLUSION

A colonoscopic surveillance program in LS patients allowed the detection of adenomas in a large group of mutation carriers and diagnosis of early-stage carcinomas. Our findings may help other teams to adopt similar strategies or to refer patients early to specialized centers.

Metachronous colorectal cancer risk in Lynch syndrome patients-should the endoscopic surveillance be more intensive?

PURPOSE

Regular follow-up for patients with Lynch syndrome (LS) is vital due to the increased risk of colorectal (50-80%), endometrial (40-60%), and other cancers. However, there is an ongoing debate concerning the best interval between colonoscopies. Currently, no specific endoscopic follow-up has been decided for LS patients who already have an index colorectal cancer (CRC). The aim of this study was to evaluate the risk of metachronous cancers (MC) after primary CRC in a LS population and to determinate if endoscopic surveillance should be more intensive.

METHODS

A prospective cohort of patients with a confirmed diagnosis of hereditary CRC since 2009 was included. Patients with LS and a primary CRC were the cohort of choice.

RESULTS

One hundred twenty-one patients were included with a median age of 44 years(16-70). At least one MC occurred in 39 patients (32.2%), with a median interval of 67 months (6-300) from index cancer. Fifteen (38.5%) developed two or more MCs during follow-up, with a median number of two (2-6) tumors occurring. Metachronous CRC were diagnosed after a median interval of 24 (6-57) months since last colonoscopy and were more commonly seen in MSH2 mutation carriers (58 vs. 35%, p = 0.001). After a median follow-up of 52.9 (3-72) months, no cancer-related deaths were recorded.

CONCLUSION

Patients with LS have an increased risk of MC, especially CRCs. With a median time period of 24 months between colonoscopy and metachronous CRC, the interval between surveillance colonoscopies following primary CRC should not exceed 18 months, especially in patients with MSH2 mutation.

Impact of an optimized colonoscopic screening program for patients with Lynch syndrome: 6-year results of a specialized French network

BACKGROUND

Despite colonoscopic screening, colorectal cancer (CRC) remains frequent in patients with Lynch syndrome (LS). The objective of this study was to evaluate the impact of an optimized colorectal screening program within a French dedicated network.

METHODS

All LS patients followed at our institution were consecutively included in the Prédisposition au Cancer Colorectal-Ile de France (PRED-IdF) network. Patients were offered an optimized screening program allowing an adjustment of the interval between colonoscopies, depending on bowel preparation, chromoendoscopy achievement and adenoma detection. Colonoscopies were defined as optimal when all the screening criteria were respected. We compared colonoscopy quality and colonoscopy detection rate before and after PRED-IdF inclusion, including polyp detection rate (PDR), adenoma detection rate (ADR) and cancer detection rate (CDR).

RESULTS

Between January 2010 and January 2016, 144 LS patients were consecutively included (male/female = 50/94, mean age = 51 ± 13 years and mutations: MLH1 = 39%, MSH2 = 44%, MSH6 = 15%, PMS2 = 1%). A total of 564 colonoscopies were analyzed, 353 after inclusion and 211 before. After PRED-IdF inclusion, 98/144 (68%) patients had optimal screening colonoscopies versus 33/132 (25%) before (p < 0.0005). The optimal colonoscopy rate was 304/353 (86%) after inclusion versus 87/211 (41%) before, (p < 0.0001). PRED-IdF inclusion was associated with a reduction of CRC occurrence with a CDR of 1/353 (0.3%) after inclusion versus 6/211 (2.8%) before (p = 0.012). ADR and PDR were 99/353 (28%) versus 60/211 (28.8%) (p > 0.05) and 167/353 (48.1%) versus 90/211 (42.2%) (p > 0.05), respectively after and before inclusion.

CONCLUSIONS

An optimized colonoscopic surveillance program in LS patients seems to improve colonoscopic screening quality and might possibly decrease colorectal interval cancer occurrence. Long-term cohort studies are needed to confirm these results.

Japanese Society for Cancer of the Colon and Rectum (JSCCR) Guidelines 2016 for the Clinical Practice of Hereditary Colorectal Cancer (Translated Version)

Hereditary colorectal cancer accounts for less than 5% of all colorectal cancer cases. Some of the unique characteristics that are commonly encountered in cases of hereditary colorectal cancer include early age at onset, synchronous/metachronous occurrence of the cancer, and association with multiple cancers in other organs, necessitating different management from sporadic colorectal cancer. While the diagnosis of familial adenomatous polyposis might be easy because usually 100 or more adenomas that develop in the colonic mucosa are in this condition, Lynch syndrome, which is the most commonly associated disease with hereditary colorectal cancer, is often missed in daily medical practice because of its relatively poorly defined clinical characteristics. In addition, the disease concept and diagnostic criteria for Lynch syndrome, which was once called hereditary non-polyposis colorectal cancer, have changed over time with continual research, thereby possibly creating confusion in clinical practice. Under these circumstances, the JSCCR Guideline Committee has developed the "JSCCR Guidelines 2016 for the Clinical Practice of Hereditary Colorectal Cancer (HCRC)," to allow delivery of appropriate medical care in daily practice to patients with familial adenomatous polyposis, Lynch syndrome, or other related diseases. The JSCCR Guidelines 2016 for HCRC were prepared by consensus reached among members of the JSCCR Guideline Committee, based on a careful review of the evidence retrieved from literature searches, and considering the medical health insurance system and actual clinical practice settings in Japan. Herein, we present the English version of the JSCCR Guidelines 2016 for HCRC.