Clinical Practice Guidelines for the Surgical Treatment of Patients With Lynch Syndrome

Treatment of Microsatellite-Unstable Rectal Cancer in Sporadic and Hereditary Settings

Microsatellite instability is rare in rectal cancer and associated with younger age of onset and Lynch syndrome. All rectal cancers should be tested for microsatellite instability prior to treatment decisions. Patients with microsatellite instability are relatively resistant to chemotherapy. However, recent small studies have shown dramatic response with neoadjuvant immunotherapy. Patients with Lynch syndrome have a hereditary predisposition to cancer and thus an elevated risk of metachronous cancer. Therefore, while "watch and wait" is a well-established practice for sporadic rectal cancers that obtain a complete clinical response after chemoradiation, its safety in patients with Lynch syndrome has not yet been defined. The extent of surgery for patients with Lynch syndrome and rectal cancer is controversial and there is significant debate as to the relative advantages of a segmental proctectomy with postoperative endoscopic surveillance versus a therapeutic and prophylactic total proctocolectomy. Surgical decision making for the patient with Lynch syndrome and rectal cancer is complex and demands a multidisciplinary approach, taking into account both patient- and tumor-specific factors. Neoadjuvant immunotherapy show great promise in the treatment of these patients, and further maturation of data from prospective trials will likely change the current treatment paradigm. Patients with Lynch syndrome and rectal cancer who do not undergo total proctocolectomy require yearly surveillance colonoscopies and should consider chemoprophylaxis with aspirin.

Management of Rectal Cancer in Lynch Syndrome: Balancing Risk Reduction and Quality of Life

Patients with Lynch syndrome are predisposed to developing colorectal cancer and a variety of extracolonic malignancies, at a young age. The management of rectal cancer in the setting of Lynch syndrome is a complex clinical scenario that requires the expertise of a multidisciplinary management team. In this review, we delve into the approach for rectal cancer in these patients, and specifically focus on several key aspects of treatment. Some unique aspects of rectal cancer in Lynch syndrome include the decision between proctectomy alone versus total proctocolectomy with or without an ileal pouch, the utility of chemotherapy and immunotherapy, nonoperative rectal cancer management, and the management of rectal polyps. Throughout, we highlight the delicate interplay between future cancer risk reduction and quality of life optimization.

ChatGPT on guidelines: Providing contextual knowledge to GPT allows it to provide advice on appropriate colonoscopy intervals

BACKGROUND AND AIM

Colonoscopy is commonly used in screening and surveillance for colorectal cancer. Multiple different guidelines provide recommendations on the interval between colonoscopies. This can be challenging for non-specialist healthcare providers to navigate. Large language models like ChatGPT are a potential tool for parsing patient histories and providing advice. However, the standard GPT model is not designed for medical use and can hallucinate. One way to overcome these challenges is to provide contextual information with medical guidelines to help the model respond accurately to queries. Our study compares the standard GPT4 against a contextualized model provided with relevant screening guidelines. We evaluated whether the models could provide correct advice for screening and surveillance intervals for colonoscopy.

METHODS

Relevant guidelines pertaining to colorectal cancer screening and surveillance were formulated into a knowledge base for GPT. We tested 62 example case scenarios (three times each) on standard GPT4 and on a contextualized model with the knowledge base.

RESULTS

The contextualized GPT4 model outperformed the standard GPT4 in all domains. No high-risk features were missed, and only two cases had hallucination of additional high-risk features. A correct interval to colonoscopy was provided in the majority of cases. Guidelines were appropriately cited in almost all cases.

CONCLUSIONS

A contextualized GPT4 model could identify high-risk features and quote appropriate guidelines without significant hallucination. It gave a correct interval to the next colonoscopy in the majority of cases. This provides proof of concept that ChatGPT with appropriate refinement can serve as an accurate physician assistant.

Preventive strategies in familial and hereditary colorectal cancer

Colorectal cancer is a leading cause of cancer-related deaths worldwide. While most cases are sporadic, a significant proportion of cases are associated with familial and hereditary syndromes. Individuals with a family history of colorectal cancer have an increased risk of developing the disease, and those with hereditary syndromes such as Lynch syndrome or familial adenomatous polyposis have a significantly higher risk. In these populations, preventive strategies are critical for reducing the incidence and mortality of colorectal cancer. This review provides an overview of current preventive strategies for individuals at increased risk of colorectal cancer due to familial or hereditary factors. The manuscript includes a discussion of risk assessment and genetic testing, highlighting the importance of identifying at-risk individuals and families. This review describes various preventive measures, including surveillance colonoscopy, chemoprevention, and prophylactic surgery, and their respective benefits and limitations. Together, this work highlights the importance of preventive strategies in familial and hereditary colorectal cancer.

Colorectal cancer treatment guidelines and shared decision making quality and reporting assessment: Systematic review

INTRODUCTION

Physicians must share decisions and choose personalised treatments regarding patients´ beliefs and values.

OBJECTIVE

To analyse the quality of the recommendations about shared decision making (SDM) in colorectal (CRC) and anal cancer treatment clinical practice guidelines (CPGs) and consensus statements (CSs).

METHODS

Guidelines were systematically reviewed following prospective registration (Prospero: CRD42021286146) without language restrictions searching 15 databases and 59 professional society websites from January 2010 to November 2021. A validated 31-item SDM quality assessment tool was employed to extract data in duplicate.

RESULTS

We identified 134 guidelines. Only 46/134 (34.3 %) mentioned SDM. Fifteen (11.1 %) made clear, precise and actionable recommendations, while 9/134 (6.7 %) indicated the strength of the SDM-related recommendations. CPGs underpinned by systematic reviews reported SDM more often than those based on consensus or reviews (35.9 % vs 32.0 %; p = 0.031). Guidelines that reported following quality tools (i.e., AGREE II) more commonly commented about SDM than when it was not reported (75.0 % vs 32.0 %; p = 0.003).

CONCLUSION AND PRACTICE IMPLICATIONS

Most of the CRC and anal treatment guidelines did not mention SDM and it was superficial. Guidelines based on systematic reviews and those using quality tools demonstrated better reporting of SDM. Recommendations about SDM in these guidelines merit urgent improvement.

A Novel Mutation of MSH2 Gene in a Patient with Lynch Syndrome Presenting with Thirteen Metachronous Malignancies

Lynch syndrome (LS), also known as hereditary nonpolyposis colorectal cancer (HNPCC), accounts for 2-3% of all colorectal cancers. This autosomal dominant disorder is associated with a predisposition to endometrial, stomach, small bowel, pancreatic, biliary tract, ovary, urinary tract, brain, and skin tumors. Lynch syndrome is caused by the mutation of the MLH1, MSH2 (EPCAM), MSH6, and PMS2 genes. In this article, a case study of a 70-year-old female patient with Lynch syndrome is presented. Over a span of 30 years, the patient underwent multiple surgical procedures for a total of thirteen different malignancies. She was found to have a deleterious pathogenic gene MSH2 (NM_000251.2) variant (mutation) c.1774_1775insT in the 12th exon. This variant, c.1774_1775insT, represents a novel finding, as it has not been previously reported in existing databases or literature. No other case of 13 metachronous tumors in a patient with Lynch syndrome was found in the literature.

Young-onset colorectal cancer

In the past decades the incidence of colorectal cancer (CRC) in people under the age of 50 years has increased, which is referred to as early-onset CRC or young-onset CRC (YO-CRC). YO-CRC is expected to account for 11% of colon cancers and 23% of rectal cancers by 2030. This trend is observed in different parts of the world and in both men and women. In 20% of patients with YO-CRC, a hereditary cancer syndrome is found as the underlying cause; however, in the majority of patients no genetic predisposition is present. Beginning in the 1950s, major changes in lifestyle such as antibiotic use, low physical activity and obesity have affected the gut microbiome and may be an important factor in YO-CRC development. Owing to a lack of screening, patients with YO-CRC are often diagnosed with advanced-stage disease. Long-term treatment-related complications should be taken into account in these younger patients, making the more traditional sequential approaches of drug therapy not always the most appropriate option. To better understand the underlying mechanism and define relationships between environmental factors and YO-CRC development, long-term prospective studies are needed with lifestyle data collected from childhood.

[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.

Lynch Syndrome Genetics and Clinical Implications

Lynch syndrome (LS) is one of the most prevalent hereditary cancer syndromes in humans and accounts for some 3% of unselected patients with colorectal or endometrial cancer and 10%-15% of those with DNA mismatch repair-deficient tumors. Previous studies have established the genetic basis of LS predisposition, but there have been significant advances recently in the understanding of the molecular pathogenesis of LS tumors, which has important implications in clinical management. At the same time, immunotherapy has revolutionized the treatment of advanced cancers with DNA mismatch repair defects. We aim to review the recent progress in the LS field and discuss how the accumulating epidemiologic, clinical, and molecular information has contributed to a more accurate and complete picture of LS, resulting in genotype- and immunologic subtype-specific strategies for surveillance, cancer prevention, and treatment.

Endometrial Cancer Diagnosed at an Early Stage during Lynch Syndrome Surveillance: A Case Report

Lynch syndrome is an autosomal dominant inherited disorder caused by a germline pathogenic variant in DNA mismatch repair genes, resulting in multi-organ cancer. Annual transvaginal ultrasonography and endometrial biopsy are recommended for endometrial cancer surveillance in patients with Lynch syndrome in several guidelines; however, evidence is limited. Here, we present the case of a 51-year-old woman with endometrial cancer who underwent robot-assisted laparoscopic simple hysterectomy at an early stage detected by Lynch syndrome surveillance. The patient was a 51-year-old gravida zero woman without any medical history or symptoms. Her sister suffered from bladder, breast, rectal, and endometrial cancer and was diagnosed with Lynch syndrome using a hereditary cancer panel test (VistaSeq®). During gynecologic surveillance, the patient's endometrial cytology was classified as Papanicolaou class III. Therefore, she underwent endometrial curettage with hysteroscopy and was diagnosed with atypical endometrial hyperplasia. Robot-assisted hysterectomy was performed with a final pathological diagnosis of endometrial cancer (endometrioid carcinoma, Grade 1), stage 1A. She has remained disease-free for more than 12 months. Owing to advances in genetic medicine, prophylactic and therapeutic surgeries for hereditary cancers are increasing. To achieve an early diagnosis and treatment of Lynch syndrome-associated cancers, the importance of Lynch syndrome surveillance should be more widely recognized.

Universal tumor screening for lynch syndrome on colorectal cancer biopsies impacts surgical treatment decisions

Universal tumor screening (UTS) for Lynch syndrome (LS) on colorectal cancer (CRC) can be performed on biopsies or resection specimens. The advantage of biopsies is the chance to provide preoperative genetic counseling/testing (GC/T) so patients diagnosed with LS can make informed decisions regarding resection extent. We evaluated utilization of UTS on biopsies, percentage of patients with deficient mismatch repair (dMMR) who underwent GC/T preoperatively, and whether surgical/treatment decisions were impacted. We performed a retrospective review of medical records to assess CRC cases with dMMR immunohistochemical staining from 1/1/2017 to 2/26/2021. 1144 CRC patients had UTS using MMR immunohistochemistry; 559 biopsies (48.9%) and 585 resections (51.1%). The main reason UTS was not performed on biopsy was it occurred outside our health system. 58 (5%) of CRCs were dMMR and did not have MLH1 promoter hypermethylation (if MLH1 and PMS2 absent). 28/58 (48.3%) of dMMR cases were diagnosed on biopsy. Of those 28, 14 (50%) eventually underwent GC/T, and 7 (25%) had GT results prior to surgery. One of the 7 had incomplete documentation of results affecting their treatment plan. Of the remaining 6 with complete documentation, 5 underwent surgery and one was treated with immunotherapy only. Three patients elected a more extensive surgery. 6/28 (21.4%) dMMR patients identified on biopsy made an informed surgical/treatment decision based on their dMMR status/LS diagnosis. When applied, UTS on biopsy followed by genetic counseling and testing informs surgical decision-making. Process and implementation strategies are in place to overcome challenges to more broadly optimize this approach.

Survival outcomes associated with Lynch syndrome colorectal cancer and metachronous rate after subtotal/total versus segmental colectomy: Meta-analysis

BACKGROUND

Lynch syndrome is associated with the most common form of heritable bowel cancer. There remains limited level 1 evidence on survival outcomes and rate of metachronous tumor associated with Lynch syndrome colorectal cancer.

METHODS

A systematic literature search of original studies was performed on Ovid searching MEDLINE, Embase, Cochrane Database of Systematic Reviews, American College of Physicians ACP Journal Club, Database of Abstracts of Reviews of Effects DARE, and Clinical Trials databases from inception of database to February 2021. The Preferred Reporting Items for Systematic Reviews and Meta-Analyses reporting guideline was followed. The data were pooled using a random-effects model. All of the P values were 2-tailed, and statistical analysis was performed using RevMan v. 5.3 Cochrane Collaboration.

RESULTS

From 1,942 studies, 15 studies met the inclusion criteria and were included for qualitative and quantitative synthesis. The five-year overall survival was 89.5% (82.0-94.1%), P < .01; I² = 89%. The ten-year overall survival was 80.5% (68.7-88.6%), P < .01; I² = 81%. The fifteen-year overall survival was 70% (33.7%-91.5%), P < .01; I² = 93%. Univariate meta-regression analysis showed no statistically significant difference in 5-year overall survival by sex, age, MLH1, MSH2, MSH6, nor tumor location (right versus left colon). The metachronous tumor rate was 12% to 33% with a follow-up period of up to 15 years, significantly lower in patients who underwent subtotal/total colectomy (0-6%).

CONCLUSION

The overall survival of patients with colorectal cancer with Lynch syndrome was approximately 90% at 5 years, 80% at 10 years, and 70% at 15 years. The metachronous tumor rate was approximately 10% to 30% at up to 15 years, significantly improved by subtotal/total colectomy.

Risk of Metachronous Colorectal Cancer in Lynch Syndrome: Who Needs an Extended Resection?

Lynch syndrome (LS) is the most common genetic condition associated with early-onset colorectal cancer. It is inherited in an autosomal dominant fashion. The increased cancer risk is due to a germline mutation in one of the mismatch repair (MMR) genes (MLH1, MSH2, MSH6, and PMS2) or the EPCAM gene. This leads to a deficient DNA mismatch repair mechanism, resulting in the accumulation of nucleotide changes and microsatellite instability, providing phenotypical evidence that MMR is not functioning normally. LS is associated with a high risk of early-onset colorectal cancer and recurrence. Thus, when undergoing surgery for primary colorectal cancer, extended resection should be discussed with the patient. This review provides an overview of current surgical risk-reducing strategies in LS-associated colorectal cancer. Surgical treatment for LS carriers with colorectal cancer needs to be highly individualized, based on patient and disease characteristics. Strategies are presented to guide decision making in pathologic MMR gene mutation carriers undergoing surgery for colorectal cancer.

Colorectal Cancer Screening Recommendations and Outcomes in Lynch Syndrome

Screening for colorectal cancer (CRC) in Lynch syndrome enables early detection and likely cancer prevention. CRC screening guidelines have evolved from universal to gene-specific recommendations based on lifetime neoplasia risks. Regular screening for Lynch syndrome reduces CRC-related mortality; however, high CRC incidence during regular colonoscopy screening suggests the possibility of nonpolypoid carcinogenesis. Colonoscopy is the primary modality for screening for Lynch syndrome with mixed and emerging data on quality metrics, chromoendoscopy, artificial intelligence, and nonendoscopic modalities. Screening adherence varies across studies. In this review, we present the current state of CRC screening recommendations, outcomes, and modalities in Lynch syndrome.

Evaluation of Urinalysis-Based Screening for Urothelial Carcinoma in Patients With Lynch Syndrome

BACKGROUND

Approximately 5% to 10% of patients with Lynch syndrome develop urothelial carcinoma. Current screening recommendations vary and are based on expert opinion. Practices need to be evaluated for clinical effectiveness. Our program utilizes urinalysis as a screening test, followed by additional evaluation of microscopic hematuria.

OBJECTIVE

This study aimed to determine the clinical utility of a urinalysis-based screening approach for urothelial cancers in patients with Lynch syndrome.

DESIGN

This is a retrospective review of a prospectively maintained cohort.

SETTING

Patients with Lynch syndrome were managed at a tertiary referral center.

PATIENTS

All patients with a Lynch syndrome diagnosis who had a screening urinalysis done as part of our institutional screening protocol (N = 204) were included.

MAIN OUTCOME MEASURES

A single-institution hereditary colorectal cancer syndrome registry was queried for patients with Lynch syndrome who had been screened for urothelial carcinomas by urinalysis. Demographics, genotype, family history of urothelial carcinoma, urinalysis results, and subsequent screenings and final diagnosis were gathered for patients between 2008 and 2017.

RESULTS

Two hundred four asymptomatic patients underwent screening by urinalysis. Nineteen patients (9.3%) had microscopic hematuria and were further evaluated with urine cytology, imaging, cystoscopy, and/or Urology consultation. None of the 19 patients with microscopic hematuria had urothelial carcinoma. During the same study period, 5 of 204 (2.4%) patients with Lynch syndrome were diagnosed with urothelial cancer, and all presented with symptoms between screening intervals.

LIMITATIONS

This is a retrospective study, and not all patients underwent the same secondary evaluation.

CONCLUSIONS

No urothelial carcinomas were detected by screening urinalysis in our cohort of asymptomatic patients with Lynch syndrome. False-positive testing led to extensive, mostly uninformative, workups. If urothelial cancer screening is to continue, more effective screening approaches need to be identified. See Video Abstract at http://links.lww.com/DCR/B702.

EVALUACIN DEL CRIBADO BASADO EN ANLISIS DE ORINA PARA CARCINOMA UROTELIAL EN PACIENTES CON SNDROME DE LYNCH

ANTECEDENTES:Aproximadamente el 5-10% de los pacientes con síndrome de Lynch desarrollan carcinoma urotelial. Las recomendaciones actuales de detección varían y se basan en la opinión de expertos. Las prácticas deben evaluarse para determinar su eficacia clínica. Nuestro programa utiliza el análisis de orina como prueba de detección, seguido de una evaluación adicional con hematuria microscópica.OBJETIVO:Determinar la utilidad clínica desde un enfoque de cribado basado en análisis de orina, para cánceres uroteliales en pacientes con síndrome de Lynch.DISEÑO:Revisión retrospectiva de una cohorte mantenida prospectivamente.ENTORNO CLINICO:Pacientes con síndrome de Lynch atendidos en un centro de referencia terciario.PACIENTES:Criterios de inclusión fueron todos los pacientes con diagnóstico de síndrome de Lynch realizándoles un análisis de orina de detección como parte de nuestro protocolo de detección institucional (N = 204).PRINCIPALES MEDIDAS DE VALORACION:Solicitando un registro de síndrome de cáncer colorrectal hereditario de una sola institución para pacientes con síndrome de Lynch previamente evaluados para carcinomas uroteliales mediante análisis de orina. Se recopilaron para los pacientes entre 2008 y 2017, datos demográficos, genotipo, antecedentes familiares de carcinoma urotelial, resultados del análisis de orina, posteriores exámenes de detección posteriores y diagnóstico final.RESULTADOS:Doscientos cuatro pacientes asintomáticos fueron sometidos a cribado mediante análisis de orina. Diecinueve pacientes (9,3%) tenían hematuria microscópica y fueron investigados más a fondo con citología de orina, imágenes, cistoscopia y / o consulta de urología. Ninguno de los 19 pacientes con hematuria microscópica tenían carcinoma urotelial. Durante el mismo período de estudio, 5 de 204 (2,4%) pacientes con síndrome de Lynch fueron diagnosticados con cáncer urotelial y todos presentaron presentando síntomas entre los intervalos de detección.LIMITACIONES:Estudio retrospectivo y no todos los pacientes sometidos a la misma evaluación secundaria.CONCLUSIONES:No se detectaron carcinomas uroteliales mediante análisis de orina de detección en nuestra cohorte de pacientes asintomáticos con síndrome de Lynch. Las pruebas de falsos positivos. Condujeron a estudios exhaustivos y en su mayoría poco informativos. Si se desea continuar con la detección del cáncer de urotelio, es necesario identificar enfoques de detección más efectivos. Consulte Video Resumen en http://links.lww.com/DCR/B702.

Genotypic and Phenotypic Characteristics of Hereditary Colorectal Cancer

The genomic causes and clinical manifestations of hereditary colorectal cancer (HCRC) might be stratified into 2 groups, namely, familial (FCRC) and a limited sense of HCRC, respectively. Otherwise, FCRC is canonically classified into 2 major categories; Lynch syndrome (LS) or associated spectra and inherited polyposis syndrome. By contrast, despite an increasing body of genotypic and phenotypic traits, some FCRC cannot be clearly differentiated as definitively single type, and the situation has become more complex as additional causative genes have been discovered. This review provides an overview of HCRC, including 6 LS or associated spectra and 8 inherited polyposis syndromes, according to molecular pathogenesis. Variants and newly-identified FCRC are particularly emphasized, including MUTYH (or MYH)-associated polyposis, Muir-Torre syndrome, constitutional mismatch repair deficiency, EPCAM-associated LS, polymerase proofreading-associated polyposis, RNF43- or NTHL1-associated serrated polyposis syndrome, PTEN hamartoma tumor syndrome, and hereditary mixed polyposis syndrome. We also comment on the clinical utility of multigene panel tests, focusing on comprehensive cancer panels that include HCRC. Finally, HCRC surveillance strategies are recommended, based on revised or notable concepts underpinned by competent validation and clinical implications, and favoring major guidelines. As hereditary syndromes are mainly attributable to genomic constitutions of distinctive ancestral groups, an integrative national HCRC registry and guideline is an urgent priority.

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.

Deciding the operation type according to mismatch repair status among hereditary nonpolyposis colorectal cancer patients: should a tailored approach be applied, or does one size fit all?

BACKGROUND

Although extended colectomy (EC) was recommended for HNPCC patients, previous studies did not show significantly improved overall survival. Immunohistochemical (IHC) stain of mismatch repair (MMR) gene protein expression is now a feasible and reliable test clinically. Therefore, we tried to investigate whether we could use MMR IHC stain to select operation types in HNPCC patients.

PATIENTS AND METHODS

Between 1995 and 2013, 186 HNPCC patients were collected. Status of MMR protein expression, perioperative clinic-pathological variables and post-operative follow up status were analyzed by multivariate analyses.

RESULTS

Sixty-five percent (121 of 186) patients of these HNPCC patients demonstrated loss of at least one MMR protein. There were several significant differences existing between deficient MMR (dMMR) and proficient MMR (pMMR) subgroups in terms of clinic-pathological characteristics. With the average follow-up duration of 93.9 months, we observed significantly high risk of developing metachronous CRC between SC and EC subgroups (crude rate 8.5% vs. 0%, p = 0.035). However, no significant difference was observed among the presence of extra-colonic tumors (12.4% vs. 5.8%, p = 0.284). The positive and negative prediction rate of metachronous CRC in dMMR subgroup was 12.8 and 87.2% while 1.9 and 98.1% in the pMMR subgroup. Survival outcomes were significantly affected by MMR status and resection types by multivariate analysis. Significantly better OS in dMMR subgroup (HR = 0.479, 95% CI: 0.257-0.894, p = 0.021) comparing with pMMR subgroup was observed. However, significant improved DFS (HR = 0.367, 95% CI: 0.172-.0787, p = 0.010) but not significant for OS (HR = 0.510, 95% CI: 0.219-1.150, p = 0.103) for EC subgroup compared with SC subgroup. Differences existing among different subgroups by combing extent of resection and MMR status. In dMMR subgroup, SC, compared with EC, demonstrated significantly worse DFS by multivariate analyses (HR = 3.526, 95% CI: 1.346-9.236, p = 0.010) but not for OS (HR = 2.387, 95% CI: 0.788-7.229, p = 0.124), however, no significantly differences of OS and DFS in pMMR subgroup between SC and EC were found.

CONCLUSIONS

Significantly better overall survival and higher rate of metachronous CRC exist in dMMR subgroup of HNPCC patients comparing with pMMR subgroup. Extended colectomy significantly improved DFS and was thus recommended for dMMR subgroup but not pMMR subgroup of HNPCC patients.

Collaborative Group of the Americas on Inherited Gastrointestinal Cancer Position statement on multigene panel testing for patients with colorectal cancer and/or polyposis

Multigene panel tests for hereditary cancer syndromes are increasingly utilized in the care of colorectal cancer (CRC) and polyposis patients. However, widespread availability of panels raises a number of questions including which patients should undergo testing, which genes should be included on panels, and the settings in which panels should be ordered and interpreted. To address this knowledge gap, key questions regarding the major issues encountered in clinical evaluation of hereditary CRC and polyposis were designed by the Collaborative Group of the Americas on Inherited Gastrointestinal Cancer Position Statement Committee and leadership. A literature search was conducted to address these questions. Recommendations were based on the best available evidence and expert opinion. This position statement addresses which genes should be included on a multigene panel for a patient with a suspected hereditary CRC or polyposis syndrome, proposes updated genetic testing criteria, discusses testing approaches for patients with mismatch repair proficient or deficient CRC, and outlines the essential elements for ordering and disclosing multigene panel test results. We acknowledge that critical gaps in access, insurance coverage, resources, and education remain barriers to high-quality, equitable care for individuals and their families at increased risk of hereditary CRC.

Characteristics of colorectal carcinoma patients with PMS2 defects detected by immunohistochemistry

Lynch syndrome is the most prevalent form of familial colorectal cancer (CRC) and is caused by pathogenic germline mismatch repair (MMR) gene mutations. MLH1, MSH2 and MSH6 mutations have been well studied, but the rate and characteristics of PMS2 mutations are rare, especially in China. This study enrolled 1706 unselected patients with CRC who underwent colorectal resection from June 2016 to November 2018, the MMR status and clinicopathological features were analysed. A total of 11.8% of patients with CRC had defects in at least one MMR-related protein. Among them, 8.3% were identified with PMS2 defects, and 3.1% of patients had isolated PMS2 defects. Compared with MMR-proficient CRC, PMS2-defect CRC occurred more frequently in the right colon and less frequently in the rectum, had more poorly differentiated and mucinous carcinoma cases, and had fewer perineural invasions and a lower pN stage but a more advanced pT stage and a larger tumour size. In the cases with PMS2 defect, there were fewer tumours in the right colon, fewer poorly differentiated cases and smaller tumour sizes than in the cases with both MLH1 and PMS2 defects. In addition, in cases with isolated PMS2 defects, there were more tumours in the right colon and, more mucinous carcinoma cases than in cases with MMR-proficient CRCs, but had a similar cancer onset age. This study identified the rate, clinicopathological and age characteristics of PMS2 defects in CRCs in China and highlighted the importance of universal screening and germline detection of PMS2 in CRC.

A Potential Role of IL-6/IL-6R in the Development and Management of Colon Cancer

Colorectal cancer (CRC) is the third most frequent cancer worldwide and the second greatest cause of cancer deaths. About 75% of all CRCs are sporadic cancers and arise following somatic mutations, while about 10% are hereditary cancers caused by germline mutations in specific genes. Several factors, such as growth factors, cytokines, and genetic or epigenetic alterations in specific oncogenes or tumor-suppressor genes, play a role during the adenoma-carcinoma sequence. Recent studies have reported an increase in interleukin-6 (IL-6) and soluble interleukin-6 receptor (sIL-6R) levels in the sera of patients affected by colon cancer that correlate with the tumor size, suggesting a potential role for IL-6 in colon cancer progression. IL-6 is a pleiotropic cytokine showing both pro- and anti-inflammatory roles. Two different types of IL-6 signaling are known. Classic IL-6 signaling involves the binding of IL-6 to its membrane receptor on the surfaces of target cells; alternatively, IL-6 binds to sIL-6R in a process called IL-6 trans-signaling. The activation of IL-6 trans-signaling by metalloproteinases has been described during colon cancer progression and metastasis, involving a shift from membrane-bound interleukin-6 receptor (IL-6R) expression on the tumor cell surface toward the release of soluble IL-6R. In this review, we aim to shed light on the role of IL-6 signaling pathway alterations in sporadic colorectal cancer and the development of familial polyposis syndrome. Furthermore, we evaluate the possible roles of IL-6 and IL-6R as biomarkers useful in disease follow-up and as potential targets for therapy, such as monoclonal antibodies against IL-6 or IL-6R, or a food-based approach against IL-6.

Uptake of hysterectomy and bilateral salpingo-oophorectomy in carriers of pathogenic mismatch repair variants: a Prospective Lynch Syndrome Database report

Purpose:

This study aimed to report the uptake of hysterectomy and/or bilateral salpingo-oophorectomy (BSO) to prevent gynaecological cancers (risk-reducing surgery [RRS]) in carriers of pathogenic MMR (path_MMR) variants.

Methods:

The Prospective Lynch Syndrome Database (PLSD) was used to investigate RRS by a cross-sectional study in 2292 female path_MMR carriers aged 30–69 years.

Results:

Overall, 144, 79, and 517 carriers underwent risk-reducing hysterectomy, BSO, or both combined, respectively. Two-thirds of procedures before 50 years of age were combined hysterectomy and BSO, and 81% of all procedures included BSO. Risk-reducing hysterectomy was performed before age 50 years in 28%, 25%, 15%, and 9%, and BSO in 26%, 25%, 14% and 13% of path_MLH1, path_MSH2, path_MSH6, and path_PMS2 carriers, respectively. Before 50 years of age, 107 of 188 (57%) BSO and 126 of 204 (62%) hysterectomies were performed in women without any prior cancer, and only 5% (20/392) were performed simultaneously with colorectal cancer (CRC) surgery.

Conclusion:

Uptake of RRS before 50 years of age was low, and RRS was rarely undertaken in association with surgical treatment of CRC. Uptake of RRS aligned poorly with gene- and age-associated risk estimates for endometrial or ovarian cancer that were published recently from PLSD and did not correspond well with current clinical guidelines. The reasons should be clarified. Decision-making on opting for or against RRS and its timing should be better aligned with predicted risk and mortality for endometrial and ovarian cancer in Lynch syndrome to improve outcomes.

Metachronous ileal cancer after surgery for ascending colon cancer in a patient with Lynch syndrome: A case report

INTRODUCTION AND IMPORTANCE

Colorectal surveillance via colonoscopy in patients with Lynch syndrome reduces the mortality of colorectal cancer. On the other hand, it is unclear whether surveillance for other malignancies, including small bowel cancer, is beneficial. We report a patient with Lynch syndrome who developed ileal cancer after surgery for ascending colon cancer.

CASE PRESENTATION

A 47-year-old man visited our hospital for a check-up for positive fecal occult blood. He was diagnosed with ascending colon cancer and met the clinical criteria for the diagnosis of Lynch syndrome based on his past and family history. The Bethesda markers demonstrated high-frequent microsatellite instability. Laparoscopy-assisted right hemicolectomy was performed. He received follow-up colonoscopy the next year, which revealed ileal cancer near the anastomosis. He underwent resection of the second cancer via a laparoscopic approach, and has been free from recurrence for five years.

CLINICAL DISCUSSION

Small bowel cancer has a dismal prognosis because a high percentage of patients were diagnosed at advanced stages. The diagnosis of metachronous ileal cancer by the first follow-up colonoscopy after surgery for ascending colon cancer offered a long disease-free survival in our patient.

CONCLUSION

The clinical course suggested the importance of inspecting the small bowel in Lynch syndrome patients, especially when colorectal cancer is diagnosed.

Prophylactic Gynecologic Surgery at Time of Colectomy Benefits Women with Lynch Syndrome and Colon Cancer: A Markov Cost-Effectiveness Analysis

BACKGROUND

Women with Lynch syndrome who have completed childbearing should be offered prophylactic hysterectomy and bilateral salpingo-oophorectomy for gynecologic cancer prevention. The benefit of prophylactic gynecologic surgery at the time of colon cancer resection is unclear.

OBJECTIVE

This study aimed to compare the cost, quality of life, and likelihood of being alive and free from colon, endometrial, and ovarian cancer between operative choices for patients with Lynch syndrome undergoing surgery for colon cancer.

DESIGN

A Markov decision tree spanning 40 years was constructed for a hypothetical cohort of 30-year-old women with Lynch syndrome who had been diagnosed with colon cancer. Outcomes of 6 surgical strategies were compared, including segmental or total abdominal colectomy with or without hysterectomy alone or combined with bilateral salpingo-oophorectomy.

SETTINGS

A Markov cost-effectiveness analysis was performed at a single center.

PATIENTS

A literature search was performed identifying studies of patients with genetically diagnosed Lynch syndrome that described cost, risk of mortality, and quality of life after colon cancer resection and prophylactic gynecologic surgery.

MAIN OUTCOME MEASURES

The primary outcomes measured were quality-adjusted life-years and the likelihood of being alive and free from colon, endometrial, and ovarian cancer 40 years after surgery.

RESULTS

Women with Lynch syndrome who underwent a total abdominal colectomy and hysterectomy with bilateral salpingo-oophorectomy had the highest likelihood of being alive and cancer free. Total abdominal colectomy with hysterectomy was a close second, but yielded the largest amount of quality-adjusted life-years and lowest cost.

LIMITATIONS

This study is limited by the statistical method and quality of studies used.

CONCLUSIONS

Total abdominal colectomy with prophylactic hysterectomy at 30 years of age was the most cost-effective surgical choice in women with Lynch syndrome and colon cancer. The addition of bilateral salpingo-oophorectomy offered the highest event-free survival and lowest mortality. However, the additional morbidity of premature menopause of prophylactic salpingo-oophorectomy for younger women outweighed the benefit of ovarian cancer prevention. See Video Abstract at http://links.lww.com/DCR/B287. LA CIRUGÍA GINECOLÓGICA PROFILÁCTICA EN EL MOMENTO DE LA COLECTOMÍA BENEFICIA A LAS MUJERES CON SÍNDROME DE LYNCH Y CÁNCER DE COLON: UN ANÁLISIS DE COSTO-EFECTIVIDAD DE MARKOV: Las mujeres con síndrome de Lynch que han completado la maternidad deberían recibir histerectomía profiláctica y salpingooforectomía bilateral para la prevención del cáncer ginecológico. El beneficio de la cirugía ginecológica profiláctica en el momento de la resección del cáncer de colon no está claro.Comparar el costo, la calidad de vida y la probabilidad de estar viva y libre de cáncer de colon, endometrio y ovario entre las opciones quirúrgicas para pacientes con síndrome de Lynch sometidos a cirugía por cáncer de colon.Se construyó un árbol de decisión de Markov que abarca cuarenta años para una cohorte hipotética de mujeres de 30 años con síndrome de Lynch diagnosticadas con cáncer de colon. Se compararon los resultados de seis estrategias quirúrgicas, incluida la colectomía abdominal segmentaria o total con o sin histerectomía sola o combinada con salpingooforectomía bilateral.Se realizó un análisis de costo-efectividad de Markov en un solo centro.se realizó una búsqueda bibliográfica para identificar estudios de pacientes con síndrome de Lynch con diagnóstico genético que describieron el costo, el riesgo de mortalidad y la calidad de vida después de la resección del cáncer de colon y la cirugía ginecológica profiláctica.años de vida ajustados por calidad y probabilidad de estar vivo y libre de cáncer de colon, endometrio y ovario 40 años después de la cirugía.Las mujeres con síndrome de Lynch que se sometieron a una colectomía e histerectomía abdominal total con salpingooforectomía bilateral tuvieron la mayor probabilidad de estar vivas y libres de cáncer. La colectomía abdominal total con histerectomía fue un segundo lugar cercano, pero produjo la mayor cantidad de años de vida ajustados por calidad y el costo más bajo.Este estudio está limitado por el método estadístico y la calidad de los estudios utilizados.La colectomía abdominal total con histerectomía profiláctica a los 30 años fue la opción quirúrgica más rentable en mujeres con síndrome de Lynch y cáncer de colon. La adición de salpingooforectomía bilateral ofreció la mayor supervivencia libre de eventos y la menor mortalidad. Sin embargo, la morbilidad adicional de la menopausia prematura de la salpingooforectomía profiláctica para las mujeres más jóvenes superó el beneficio de la prevención del cáncer de ovario. Consulte Video Resumen en http://links.lww.com/DCR/B287. (Traducción-Dr. Yesenia Rojas-Khalil).

Analysis of morbidity and mortality, quality of life and bowel function after total colectomy with ileorectal anastomosis versus right and left hemicolectomy: A study to optimise the treatment of lynch syndrome and attenuated polyposis coli

BACKGROUND

The optimal surgical treatment for colonic colorectal carcinoma (CRC) in Lynch Syndrome (LS) and attenuated polyposis coli (A-FAP phenotype) patients is still debated, since there is a high risk of metachronous colonic adenomas and carcinoma after primary surgery. The aim of this study was to compare surgical outcome, functional data, and Quality of Life (QoL) after total colectomy with ileorectal anastomosis (TC-IRA) compared to right (RH) or left hemicolectomy/sigmoidectomy (LH/SI).

METHODS

Patients who underwent TC-IRA (ileorectal anastomosis from 8 to 15 cm from the anal verge) for CRC and/or polyposis at our Surgical Department between 2001 and 2017 were included in the study group, and were matched one-to-one by baseline and clinical characteristics with a control group of RH and LH/SI. Morbidity and mortality data were collected (Clavien-Dindo classification). International validated questionnaires were used to investigate QoL and bowel function.

RESULTS

Fifty-five patients were enrolled in each group. No differences were found on length of hospital stay, Clavien-Dindo grade III-IV complications and mortality (p > 0.05). TC-IRA showed a longer operative time than RH and LH/SI (p < 0.0001) and a major blood loss than RH (p < 0.0001). Worse bowel function and worse QoL, only for the bowel-related items, were recorded in TC-IRA group. The general QoL was similar among the groups.

CONCLUSIONS

TC-IRA and segmental resection have similar morbidity and mortality. The worse bowel function in TC-IRA group does not impact on the general QoL. These data can be useful in the setting of risk-reducing surgery decision in LS and A-FAP patients.

Entirely Robot-assisted Total Colectomy/Total Proctocolectomy Compared With a Laparoscopic Approach

PURPOSE

Previous robot-assisted total colectomy/total proctocolectomy (TC/TPC) has been mostly confined to completion proctectomy combined with open or laparoscopic colon dissection. This study describes an integrative method of entirely robot-assisted maintaining anatomical dissection with single docking and one-off arm placement.

MATERIALS AND METHODS

Twenty patients who underwent robot-assisted TC/TPC and 36 who underwent laparoscopic procedures at the Asan Medical Center (Seoul, Korea) were enrolled.

RESULTS

Mean operation time was ∼1 hour longer in the robot-assisted than in the laparoscopic group (P=0.003), due primarily to the extra time required for instrument installation and more frequent transient ileal diversion. Three patients (8%) in the laparoscopic group required conversion to open surgery, compared with none in the robot-assisted group. Rates of postoperative adverse events did not differ in the 2 groups (P=0.063). Short (8 cm) ileal pouches were applied to all patients who underwent robot-assisted TPC/ileal-pouch anal anastomosis, but to one patient who underwent laparoscopic surgery. There were no discrepancies of mean daily bowel movement between patients with short and long ileal pouches 6 months after surgery (P=0.694), showing 5 times per day (range: 1 to 10).

CONCLUSION

The advantages of the boom system and motion-sensitive table were successfully utilized to integrate anatomical dissection with the multiquadrant procedures of TC/TPC, with none of these patients requiring conversion to open surgery. Refinement of these techniques may overcome some of the technical and time-related and cost-related concerns of the robotic approach.

Colorectal family polyadenomatous diseases. What management in 2020?

Nearly 5% of colorectal cancers are hereditary colorectal cancers, including adenomatous polyposis. The aim of this review was to highlight the current management of adenomatous polyposis. The two main genetic conditions responsible for adenomatous polyposis are familial adenomatous polyposis (FAP) (caused by an autosomal dominant mutation of the APC gene) and MUTYH-associated polyposis (MAP) (caused by bi-allelic recessive mutations of the MUTYH (MutY human homolog) gene). FAP is characterized by the presence of >1000 polyps and a young age at diagnosis (mean age of 10). In the absence of screening, the risk of colorectal cancer at age 40 is 100%. It is recommended to start screening at the age of 10-12 years. For patients with FAP and MAP, it is also recommended to screen the upper gastrointestinal tract (stomach and duodenum). In FAP, prophylactic surgery aims to reduce the risk of death without impairment of patient quality of life. The best age for prophylactic surgery is not well-defined; in Europe, prophylactic surgery is usually performed at age 20 as the risk of cancer increases sharply during the third decade. There are three main surgical procedures employed: total colectomy with an ileorectal anastomosis, restorative coloproctectomy with a J pouch anastomosis and coloproctectomy with a stoma. Restorative coloproctectomy with J pouch anastomosis is the reference procedure; however, disease can vary in severity from one patient to another and this must be taken into account to decide which procedure should be performed. In conclusion, the management of adenomatous polyposis is complex but is well-defined by guidelines, particularly in France.

Factors associated with decision-making on prophylactic hysterectomy and attitudes towards gynecological surveillance among women with Lynch syndrome (LS): a descriptive study

To prevent endometrial carcinoma in Lynch syndrome (LS), regular gynecological surveillance visits and prophylactic surgery are recommended. Previous data have shown that prophylactic hysterectomy is an effective means of cancer prevention, while the advantages and disadvantages of surveillance are somewhat unclear. We aimed to evaluate female LS carriers’ attitudes towards regular gynecological surveillance and factors influencing their decision-making on prophylactic surgery that have not been well documented. Pain experienced during endometrial biopsies was also evaluated. Postal questionnaires were sent to LS carriers undergoing regular gynecological surveillance. Questionnaires were sent to 112 women with LS, of whom 76 responded (68%). Forty-two (55%) had undergone prophylactic hysterectomy by the time of the study. The majority of responders (64/76; 84.2%) considered surveillance appointments beneficial. Pain level during endometrial biopsy was not associated with the decision to undergo prophylactic surgery. The level of satisfaction the women had with the information and advice provided during surveillance was significantly associated with the history of prophylactic hysterectomy (satisfaction rate of 73.2% versus 31.8% of nonoperated women, p = 0.003). The women who had undergone prophylactic surgery were older than the nonoperated women both at mutation testing (median of 42.3 years versus 31.6 years, p < 0.001) and at the time of the study (median of 56.9 years versus 46.0 years, respectively, p < 0.001). Women with LS pathogenic variants have positive experiences with gynecological surveillance visits, and their perception of the quality of the information and advice obtained plays an important role in their decision-making concerning prophylactic surgery.

Colorectal Cancer in the Adolescent and Young Adult Population

Colorectal cancer in the young adult population is of increasing incidence and concern. Genetic predisposition and heritable syndromes contribute to this trend, but perhaps more concerning is the majority of new diagnoses that involve no traceable genetic risk factors. Prevention and early recognition, with a high suspicion in the symptomatic young adult, are critical in attenuating recent trends. Clinical management requires coordinated multidisciplinary care from diagnosis to surveillance in order to ensure appropriate management. This review provides a summary of key aspects related to colorectal cancer in adolescents and young adults, including epidemiology, biology, genetics, clinical management, and prevention.

Promising Colorectal Cancer Biomarkers for Precision Prevention and Therapy

Colorectal cancer (CRC) has been ranked as the third most prevalent cancer worldwide. Indeed, it represents 10.2% of all cancer cases. It is also the second most common cause of cancer mortality, and accounted for about 9.2% of all cancer deaths in 2018. Early detection together with a correct diagnosis and staging remains the most effective clinical strategy in terms of disease recovery. Thanks to advances in diagnostic techniques, and improvements of surgical adjuvant and palliative therapies, the mortality rate of CRC has decreased by more than 20% in the last decade. Cancer biomarkers for the early detection of CRC, its management, treatment and follow-up have contributed to the decrease in CRC mortality. Herein, we provide an overview of molecular biomarkers from tumor tissues and liquid biopsies that are approved for use in the CRC clinical setting for early detection, follow-up, and precision therapy, and of biomarkers that have not yet been officially validated and are, nowadays, under investigation.

Incident colorectal cancer in Lynch syndrome is usually not preceded by compromised quality of colonoscopy

Background: Lifetime incidence of colorectal cancer (CRC) especially in carriers of MLH1 and MSH2 pathogenic germline variants in mismatch repair genes is high despite ongoing colonoscopy surveillance. Lynch syndrome (LS) registries have been criticized for not reporting colonoscopy quality adequately.Methods: Prospective follow-up data from the national registry were combined with a retrospective assessment of the colonoscopy reports from Helsinki University Hospital electronic patients records in 2004-2019.Results: Total of 366 MLH1, MSH2 and MSH6 carriers underwent 1564 colorectal endoscopies (mean 4.3 per patient, range 1-10) at a single unit. At least one subsequent examination was performed on 336 patients.Bowel preparation was suboptimal (Boston Bowel Preparation Scale 0-2) on either right or left side of the colon in 12.9% of planned surveillance examinations. Caecal intubation rate for full-length colonoscopies was 98.9%. Adenoma detection rate (ADR) was 15.8% in 2004-2014 but substantially increased (21.9%) after introduction of high-definition (HD) technology in 2015-2019 (p = .004; 18.7% across all examinations).CRCs were detected in 23 cases. Nineteen cancers were detected after 977 optimal quality colonoscopies and 4 after 151 compromised quality (BBPS <3 or non-complete examination; p = .16). Advanced neoplasias were not more frequently reported after compromised quality examinations.Conclusion: The majority of LS-associated incident CRCs were detected after colonoscopies with proper bowel preparation and complete examination. There is a considerable time trend towards higher ADR after introducing HD technology of endoscopes. The effect of time trend in ADR to CRC incidence in LS needs to be studied in larger, prospective settings.

Diagnosis and Management of Lynch Syndrome

A 56-year-old man with a history of hypertension and hyperlipidemia was referred by gastroenterology for bleeding per rectum. Because of a family history of colon cancer, he had several prior colonoscopies, most recently 3 years ago, without evidence of pathology. His mother was diagnosed with colon cancer in her mid-40s. His current colonoscopy demonstrated a 2.4 × 1.5 cm cecal adenocarcinoma. Staging workup revealed no evidence of metastatic disease. Because of the patient's family history, the specimen was further evaluated and found to have high microsatellite instability (MSI-H). The patient was referred to a genetic counselor and found to have a germline pathogenic variant in MSH6 on gene panel testing. The patient did not have a family history of any extracolonic malignancies.The patient underwent an uncomplicated laparoscopic total abdominal colectomy with ileorectal anastomosis, which revealed a T2N0Mx adenocarcinoma with abundant peritumoral lymphocytes. He was discharged on postoperative day 2, and recuperated appropriately from surgery. Follow-up surveillance proctoscopy showed no evidence of disease. His sole offspring, a 25-year-old man, was negative for a pathogenic variant in MSH6 and had no polyps on colonoscopy. His siblings did demonstrate a pathogenic variant in MSH6 and are currently opting for annual surveillance colonoscopy.

Total abdominal colectomy is cost-effective in treating colorectal cancer in patients with genetically diagnosed Lynch Syndrome

BACKGROUND

Lynch syndrome (LS) has a 80% lifetime risk of developing colorectal cancer and metachronous cancer. No studies have examined the quality adjusted life expectancy after SEG or TAC for LS patients, which this study was aiming for. If TAC offers a higher quality adjusted life year (QALY) to SEG in LS patients, preoperative diagnosis of LS is critical as it alters the recommended surgical procedure.

METHODS

A Markov decision tree was constructed using Treeage software to compare QALY of LS patients following SEG or TAC. Probabilities, cost, and utility were obtained from literature. Cost-effectiveness analyses were performed.

RESULTS

TAC dominates SEG as both the life-saving and cost-saving strategy. TAC dominated SEG on QALY (17.80 vs 17.13 QALY) for a cohort of LS patients diagnosed at an average of 30 year old and followed every 2 years after initial surgery.

CONCLUSIONS

We conclude that TAC as the primary surgical option for LS patients diagnosed with Stage I-III colon cancer is cost-effective. Further cost-effectiveness study is recommended to include extra-colonic malignancies in LS patients.

Phenotypic and genotypic heterogeneity of Lynch syndrome: a complex diagnostic challenge

Lynch syndrome is the hereditary disorder that most frequently predisposes to colorectal cancer as well as predisposing to a number of extracolonic cancers, most prominently endometrial cancer. It is caused by germline mutations in the mismatch repair genes. Both its phenotype and genotype show marked heterogeneity. This review gives a historical overview of the syndrome, its heterogeneity, its genomic landscape, and its implications for complex diagnosis, genetic counseling and putative implications for immunotherapy.

Targeted Next-Generation Sequencing of MLH1, MSH2, and MSH6 Genes in Patients with Endometrial Carcinoma under 50 Years of Age

Background

Lynch syndrome is an inherited cancer disorder that causes an increased lifetime risk of various types of cancers. Endometrial cancer is the most common extracolonic cancer in Lynch syndrome. Guidelines recommend that patients with endometrial cancer younger than 50 years of age should be evaluated for Lynch syndrome. Molecular analysis of the mismatch repair genes and EPCAM gene is required for a definitive diagnosis of Lynch syndrome.

Aims

To report the mutation analysis of mismatch repair genes using targeted next-generation sequencing in endometrial cancer diagnosed patients <50 years of age.

Study Design

Retrospective cross-sectional study.

Methods

Seventy-nine endometrial cancer diagnosed patients <50 years of age underwent genetic counseling. They were selected among 1094 consecutive endometrial cancer patients between 2006 and 2017. Molecular analysis of MLH1, MSH2, and MSH6 genes was performed in 79 patients by using next-generation sequencing. Deletion/duplication analysis of mismatch repair genes and EPCAM gene was also performed in 79 patients by using the multiplex ligation-dependent probe amplification method.

Results

Germline testing of mismatch repair genes was performed in 79 endometrial cancer patients. Lynch syndrome was confirmed in 4 patients (5%; 4/79). A total of 14 variants (6 in MSH2, 5 in MLH1, 3 in MSH6 genes) were found in 14 patients. Four variants were assessed as pathogenic/likely pathogenic, and 10 variants were assessed as variants of uncertain significance.

Conclusion

Lynch syndrome should be investigated in patients diagnosed with endometrial cancer that are less than 50 years of age due to the increased lifetime risk of developing cancer.

Barriers to Lynch Syndrome Testing and Preoperative Result Availability in Early-onset Colorectal Cancer: A National Physician Survey Study

Objective

Although widely recommended, Lynch syndrome (LS) testing with tumor microsatellite instability (MSI) and/or immunohistochemistry (IHC) is infrequently performed in early-onset colorectal cancer (CRC), and CRC generally. Reasons are poorly understood. Hence, we conducted a national survey focusing on gastroenterologists, as they are frequently first to diagnose CRC, assessing testing barriers and which specialist is felt responsible for ordering MSI/IHC. Additionally, we assessed factors influencing timing of MSI/IHC ordering; testing on colonoscopy biopsy, opposed to post-operative surgical specimens, assists decisions on preoperative germline genetic testing and extent of colonic resection (ECR).

Methods

A 21-question web-based survey was distributed through an American College of Gastroenterology email listing.

Results

In total 509 completed the survey. 442 confirmed gastroenterologists were analyzed. Only 33.4% felt gastroenterologists were responsible for MSI/IHC ordering; pathologists were believed most responsible (38.6%). Cost, unfamiliarity interpreting results and unavailable genetic counseling most commonly prevented routine ordering (33.3%, 29.2%, 24.9%, respectively). In multivariable analysis, non-academic and rural settings were associated with cost and genetic counseling barriers. Only 46.1% felt MSI/IHC should always be performed on colonoscopy biopsy. Guideline familiarity predicted whether respondents felt surgical resection should be delayed until results returned given potential effect on ECR decisions.

Conclusion

Inconsistencies in who is felt should order MSI/IHC may lead to diffusion of responsibility, preventing consistent testing, including preoperatively. Assuring institutional universal testing protocols are in place, with focus on timing of testing, can optimize care. Strategies addressing cost barriers and genomic service availability in rural and non-academic settings can enhance testing. Greater emphasis on guideline familiarity is required.

Colorectal polyposis and inherited colorectal cancer syndromes

The majority of colorectal cancer (CRC) cases are sporadic, with hereditary factors contributing to approximately 35% of CRC cases. Less than 5% of CRC is associated with a known genetic syndrome. Although adenomatous polyposis syndromes, hamartomatous polyposis syndromes, and those previously classified as non-polyposis CRC syndromes are quite rare, it is important for clinicians to know the characteristics of each syndrome and to understand the differences in cancer risks between the different conditions. This information is very important when treatment and surveillance plans are formulated for each individual patient.

The American Society of Colon and Rectal Surgeons Clinical Practice Guidelines for the Treatment of Colon Cancer

The American Society of Colon and Rectal Surgeons is dedicated to ensuring high-quality patient care by advancing the science, prevention, and management of disorders and diseases of the colon, rectum, and anus. The Clinical Practice Guidelines Committee is composed of society members who are chosen because they have demonstrated expertise in the specialty of colon and rectal surgery. This committee was created to lead international efforts in defining quality care for conditions related to the colon, rectum, and anus. This is accompanied by developing Clinical Practice Guidelines based on the best available evidence. These guidelines are inclusive and not prescriptive. Their purpose is to provide information on which decisions can be made, rather than to dictate a specific form of treatment. These guidelines are intended for the use of all practitioners, health care workers, and patients who desire information about the management of the conditions addressed by the topics covered in these guidelines. It should be recognized that these guidelines should not be deemed inclusive of all proper methods of care or exclusive of methods of care reasonably directed to obtaining the same results. The ultimate judgment regarding the propriety of any specific procedure must be made by the physician in light of all the circumstances presented by the individual patient.

Colorectal cancer in young adults: A difficult challenge

Sporadic colorectal cancer (CRC) is traditionally diagnosed after the sixth decade of life, and current recommendations for surveillance include only patients older than 50 years of age. However, an increasing incidence of CRC in patients less than 40 years of age has been reported. This occurrence has been attributed to different molecular features and low suspicion of CRC in young symptomatic individuals. When confronting young-onset CRC with older patients, issues such as biological aggressiveness, stage at diagnosis and clinical outcomes seem to differ in many aspects. In the future, the identification of the molecular profile underlying the early development of sporadic CRC will help to plan tailored screening recommendations and improve management. Besides that, differential diagnosis with CRC linked with hereditary syndromes is necessary to provide adequate patient treatment and family screening. Until we find the answers to some of these doubts, doctors should raise suspicion when evaluating an young adult and be aware of this risk and consequences of a late diagnosis.