Hereditary gastrointestinal cancers: ESMO Clinical Practice Guidelines for diagnosis, treatment and follow-up†

Low risk, high cost: challenging the role of gastric cancer screening in low-prevalence countries

Gastric cancer is the second commonest gastrointestinal (GI) neoplasm, with a high mortality rate and highly variable regional incidence data associated with factors such as diet, genetics, and infection with Helicobacter pylori. In high-risk countries as Japan and South Korea endoscopic screening has shown its potential to reduce this cancer's mortality. However, in low-risk countries such as Spain, where population screening is not cost-effective, a selective approach is advised focused on high-risk groups, including patients with a family history of gastric cancer, or in the form of opportunistic screening during gastroscopy for other clinical indications. High-quality gastroscopy is key for the identification of early lesions. This includes using high-definition endoscopes with chromoendoscopy, pursuing optimal mucosal visibility with washes or premedication, systematically inspecting all of the mucosa, investing adequate observation times, and using risk stratification tools such as EGGIM or OLGIM. Endoscopic surveillance is particularly advisable for high-risk precursor lesions, with intervals adjusted for patient profile. Further research is crucial for optimizing these interventions and reducing the condition's mortality rate.

Pathogenic germline variants in patients with early-onset colorectal cancer according to phenotype

We assessed retrospectively the prevalence of pathogenic germline variants (PGV) in 268 French adult patients diagnosed with colorectal cancer (CRC) before age 41, stratified by phenotype. APC, BMPR1A, CDH1, EPCAM, MLH1, MSH2, MSH3, MSH6, MUTYH, NTHL1, POLE, POLD1, PTEN, PMS2, SMAD4, STK11 and TP53 were analyzed. Overall, 21.6% of cases carried a PGV. A high prevalence was observed in Mismatch Repair-deficient (MMRd) CRC (60.1%, MMR genes) and polyposis-associated CRC (48%, APC, MUTYH and MSH3-biallelic, POLE). Only 2.3% of patients with MMR proficient and without polyposis carried a PGV. The genes involved in this third group were POLE and MSH2, and three out of four cases had either two synchronous CRC or a CRC family history. Phenotypic features should be taken into account for testing decision. Evaluating the cost-effectiveness of testing all CRC cases < 41 years, as well as how it aligns with the constraints of various healthcare systems, is warranted.

Practice guideline for management of endometrial cancer in Thailand: a Thai Gynecologic Cancer Society consensus statement

The Thai Gynecologic Cancer Society (TGCS) continues its efforts to elevate the standard of practice of gynecologic oncologists across all regions of Thailand. A key initiative involves collaborating with the Royal Thai College of Obstetricians and Gynaecologists and the National Cancer Institute, Thailand to regularly update and release clinical practice guidelines (CPGs) for gynecologic cancer. The TGCS released the first CPG for endometrial cancer (EMC) in 2011. Following significant advancements in disease understanding and the major revision of EMC staging by the International Federation of Gynecology and Obstetrics in 2023, national experts collaborated to update the guideline for EMC. The key components of the CPG for EMC covered screening, diagnostic indications and methods, primary treatment including surgical approaches and procedures, pathological processes, adjuvant therapies, and the management of recurrent and advanced diseases through medical or surgical means. The guideline was based on scientific evidence, recommendations from international organizations, and the unique healthcare context of Thailand. The final version reflects a consensus reached through extensive discussions among TGCS members. To share our work with international organizations and healthcare professionals, an English version of the CPG was developed. While it mirrors the content of the Thai version, it differs in length and level of detail. The English version additionally included the level of evidence and a recommendation summary for each section, reflecting common domestic practices, available resources, and coverage under health reimbursement systems.

Lynch Syndrome: Similarities and Differences of Recommendations in Published Guidelines

BACKGROUND

In this review, we aimed to compare the recommendations for Lynch syndrome (LS).

METHODS

We compared the LS's guidelines of different medical societies, including recommendations for cancer surveillance, aspirin treatment, and universal screening.

RESULTS

Most guidelines for LS patients recommend intervals of 1-2 years for performing colonoscopy, though there is disagreement regarding the age to begin CRC screening (dependent on status as a MLH1/MSH2 or MSH6/PMS2 carrier). There are inconsistencies between LS guidelines for gastric cancer surveillance. Most guidelines do not recommend routine surveillance of the pancreas and small bowel. Most but not all of the guidelines support endometrial and ovarian surveillance with transvaginal ultrasound and endometrial biopsy. Only two societies recommend urological surveillance, while others recommend surveillance among high-risk carriers with family history only. There is significant disagreement between the guidelines about the recommendation for limited or extended bowel resection among patients with CRC. Aspirin use is recommended by most societies, though some with reservations, and most of them recommend universal screening.

CONCLUSIONS

There are significant disparities and disagreements in the guidelines and recommendations for patients with LS, causing confusion and difficulties for clinicians. Harmonization and cooperation are needed between the societies creating LS guidelines.

Comprehensive histopathological analysis of gastric cancer in European and Latin America populations reveals differences in PDL1, HER2, p53 and MUC6 expression

INTRODUCTION

Gastric cancer (GC) burden is currently evolving with regional differences associated with complex behavioural, environmental, and genetic risk factors. The LEGACy study is a Horizon 2020-funded multi-institutional research project conducted prospectively to provide comprehensive data on the tumour biological characteristics of gastroesophageal cancer from European and LATAM countries.

MATERIAL AND METHODS

Treatment-naïve advanced gastroesophageal adenocarcinoma patients were prospectively recruited in seven European and LATAM countries. Formalin-fixed paraffin-embedded primary tumour endoscopic biopsy samples were collected and submitted for central morphological and immunohistochemical characterization and TP53 molecular assessment and Helicobacter pylori infection.

RESULTS

A total of 259 patients were included in the study: 137 (53%) from LATAM and 122 (47%) from Europe. Significant biological differences were detected between European and LATAM patients. Low representation of chromosomal instability (CIN) and HER2 positive cases were found in LATAM. MUC6 and PD-L1 were more frequently overexpressed in European cases, showing a significant correlation across the entire study population, with this association being especially pronounced in MMRdeficient cases. Both TP53 mutation by next-generation sequencing and p53 immunohistochemical aberrant pattern were linked with features associated with chromosomal instability. No regional differences were observed in H. pylori prevalence or abundance, indicating that the afore mentioned variations cannot be attributed to this factor.

CONCLUSION

Our findings underscore a need for region-specific approaches in gastroesophageal cancer diagnosis and treatment. MUC6 emerges as a putative immune regulator that needs further investigation. Research tailored to the unique biological profiles in different global regions is crucial to effectively address the observed disparities.

MSH2, MSH6, MLH1, and PMS2 immunohistochemistry as highly sensitive screening method for DNA mismatch repair deficiency syndromes in pediatric high-grade glioma

Pediatric high-grade glioma (pedHGG) can occur as first manifestation of cancer predisposition syndromes resulting from pathogenic germline variants in the DNA mismatch repair (MMR) genes MSH2, MSH6, MLH1, and PMS2. The aim of this study was to establish a generalized screening for Lynch syndrome and constitutional MMR deficiency (CMMRD) in pedHGG patients, as the detection of MMR deficiencies (MMRD) may enable the upfront therapeutic use of checkpoint inhibitors and identification of variant carriers in the patients' families. We prospectively enrolled 155 centrally reviewed primary pedHGG patients for MMR-immunohistochemistry (IHC) as part of the HIT-HGG-2013 trial protocol. MMR-IHC results were subsequently compared to independently collected germline sequencing data (whole exome sequencing or pan-cancer DNA panel next-generation sequencing) available in the HIT-HGG-2013, INFORM, and MNP2.0 trials. MMR-IHC could be successfully performed in 127/155 tumor tissues. The screening identified all present cases with Lynch syndrome or CMMRD (5.5%). In addition, MMR-IHC also detected cases with exclusive somatic MMR gene alterations (2.3%), including MSH2 hypermethylation as an alternative epigenetic silencing mechanism. Most of the identified pedHGG MMRD patients had no family history of MMRD, and thus, they represented index patients in their families. Cases with regular protein expression in MMR-IHC never showed evidence for MMRD in DNA sequencing. In conclusion, MMR-IHC presents a cost-effective, relatively widely available, and fast screening method for germline MMRD in pedHGG with high sensitivity (100%) and specificity (96%). Given the relatively high prevalence of previously undetected MMRD cases among pedHGG patients, we strongly recommend incorporating MMR-IHC into routine diagnostics.

Influence of Lifestyles on Polyp Burden and Cancer Development in Hereditary Colorectal Cancer Syndromes

BACKGROUND

Whether the progression of precursor lesions or the occurrence of cancer is influenced by lifestyle factors in carriers of genetic mutations has not been fully investigated, especially in Asian patients of hereditary colorectal cancer (CRC) syndrome.

METHODS

Patients at a high risk of hereditary CRC were included. For polyposis CRC syndromes, colorectal polyp burden was measured using at least 60 images per colonoscopy in each patient and classified into five stages using the International Society for Gastrointestinal Hereditary Tumours staging system according to the polyp number and size. Increase in tumor burden stage for polyposis CRC syndrome and the occurrence of CRC or any cancer for Lynch syndrome were analyzed according to lifestyle factors.

RESULTS

Ninety-six patients with suspected hereditary polyposis CRC syndrome and 106 patients with Lynch syndrome were recruited. For polyposis CRC syndromes, multivariate analysis showed that exposure to smoking and > 100 polyps independently predicted a high risk of increased polyp burden (p = 0.008 and p = 0.012, respectively). Significant genetic mutations or phenotype of polyposis syndromes were significantly associated with an increased polyp burden. For Lynch syndrome, smokers showed to be diagnosed with CRC in younger age than never-smokers (42.2 years vs. 49.0 years; p = 0.021), and heavy drinkers had high risk for occurrence of CRC (HR, 2.381, 95% CI, 1.338-4.236; p = 0.003) and any cancer (HR, 2.254; 95% CI, 1.334-3.806; p = 0.002).

CONCLUSIONS

The lifestyle factors (smoking and alcohol consumption) were associated with increasing precursor lesions and occurrence of cancer in patients with hereditary CRC syndrome. Lifestyle modifications may reduce the risk of hereditary CRC in carriers.

MLH1 gene promoter methylation status partially overlaps with CpG methylator phenotype (CIMP) in colorectal adenocarcinoma

BACKGROUND

RAS/BRAF mutations, mismatch DNA repair complex deficiency (MMRd)/microsatellite instability (MSI), and CpG methylator phenotype (CIMP) are key molecular actors in colorectal carcinogenesis. To date, conflicting evidence about the correlations between these molecular features has been reported.

MATERIALS AND METHODS

A retrospectively selected cohort of 123 CRCs was divided into 3 groups based on the molecular characteristics: MMR proficient (MMRp)/BRAF p.V600E mutated (BRAFmut), MMRd/BRAFmut, and MMRd/BRAF wild type (BRAFwt). MLH1 promoter (pMLH1) methylation status was assessed by pyrosequencing. For 82 samples the CIMP phenotype was evaluated using the EpiTect® MethyLight kit.

RESULTS

The MMRd/BRAFmut group showed a higher pMLH1 methylation rate compared to both the MMRd/BRAFwt and the MMRp/BRAFmut groups. Overall, the two MMRd groups had a higher methylation rate compared to the MMRp cases independently from the mutational status of BRAF (p-value <0.0001). The MMRd/BRAFmut group was characterized by a 90.0 % of CIMP high (CIMP-H) tumors of which 97.2 % were pMLH1 methylated. Instead, the MMRd/BRAFwt group presented 50.0 % of CIMP-H adenocarcinomas.

CONCLUSIONS

Our study demonstrates that pMLH1 hypermethylation, MMRd, BRAFmut and CIMP phenotype do not completely overlap in CRC. These findings further refine the knowledge on the molecular landscape of CRC and may have critical implications also for the clinical management of the disease.

Predictive modeling for the germline pathogenic variant of the APC gene in patients with adenomatous polyposis: proposing a new APC score

BACKGROUND

The precise diagnosis and medical management of patients with suspected familial adenomatous polyposis should be based on genetic testing, which may not always be available. Therefore, establishing a new model for predicting the likelihood of a germline pathogenic variant (GPV) of APC based on its clinical manifestations could prove to be useful in clinical practice.

METHODS

The presence of GPVs of APC gene was investigated in 162 patients with adenomatous polyposis (≥ 10 polyps) using a multigene panel or single-gene testing. To generate a predictive model for GPV of the APC gene, a logistic regression analysis was performed using the clinicopathological variables available at the time of the diagnosis of adenomatous polyposis.

RESULTS

Ninety (55.6%) patients had GPV of the APC gene. According to a multivariate logistic regression analysis, age < 40 years, polyps ≥ 100, fundic gland polyposis, and a family history of colorectal polyposis were found to be independent predictors of the GPV of APC and were used to establish a formula for predicting the GPV of APC using the four predictors. The prediction model had an area under the curve of 0.91 (0.86-0.96) according to a receiver operating characteristic analysis.

CONCLUSION

The model for predicting the GPV of APC will help patients with adenomatous polyposis and physicians make decisions about genetic testing.

Lynch Syndrome-Impact of the Type of Deficient Mismatch Repair Gene Mutation on Diagnosis, Clinical Presentation, Surveillance and Therapeutic Approaches

In today's world, with its continuing advancements in genetics, the identification of Lynch syndrome (LS) increasingly relies on sophisticated genetic testing techniques. Most guidelines recommend a tailored surveillance program, as well as personalized prophylactic and therapeutic approaches, according to the type of dMMR gene mutation. Carriers of path_MLH1 and path_MSH2 genes have a higher risk of developing colorectal cancer (CRC), despite intensive colonoscopic surveillance. Conversely, carriers of path_MSH6 and path_PMS2 genes have a lower risk of developing CRC, which may be due to their lower penetrance and later age of onset. Thus, carriers of path_MLH1 or path_MSH2 would theoretically derive greater benefits from total colectomy, compared to low-risk carriers (path_MSH6 and path_PMS2), in which colonoscopic surveillance might achieve an efficient prophylaxis. Furthermore, regarding the risk of endometrial/ovarian cancer development, there is a global agreement to offer both hysterectomy and bilateral salpingo-oophorectomy to path_MLH1, path_MSH2 and path_MSH6 carriers after the age of 40. In patients with CRC, preoperative knowledge of the diagnosis of LS is of tremendous importance, due to the high risk of metachronous CRC. However, this risk depends on the type of dMMR gene mutation. For carriers of the high-risk variants (MLH1, MSH2 and EPCAM) who have already developed colon cancer, it is strongly recommended a subtotal or total colectomy is performed, while partial colectomy followed by endoscopic surveillance is an appropriate management approach to treat colon cancer in carriers of the low-risk variants (MSH6 and PMS2). On the other hand, extended surgery for index rectal cancer (such as total proctocolectomy) is less effective than extended surgery for index colon cancer from the point of view of metachronous CRC risk reduction, and is associated with a decreased quality of life.

Genetic predisposition to polyposis syndromes

Hereditary polyposis syndromes are significant contributors to colorectal cancer (CRC). These syndromes are characterized by the development of various types and numbers of polyps, distinct inheritance patterns, and extracolonic manifestations. This review explores these syndromes with a focus on their genetic characteristics. Advances in diagnostics, particularly the identification of pathogenic germline variants through massive sequencing technologies, have enhanced our understanding of the genetic alterations associated with polyp formation and CRC risk. Identifying pathogenic variants beyond traditional diagnostic criteria improves the management and surveillance of these syndromes. Genetic diagnosis not only refines patient treatment and surveillance, but also informs relatives of potential risks, enabling appropriate management. However, challenges persist in determining the pathogenicity of newly discovered mutations due to their low prevalence. This review covers hereditary polyposis syndromes, from well-established to newly recognized types, providing insights into their genetic landscapes and highlighting the need for tailored surveillance based on genotype.

Comparison of PREMM5 and PREMMplus Risk Assessment Models to Identify Lynch Syndrome

PURPOSE

Clinical risk assessment models can identify patients with hereditary cancer susceptibility, but it is unknown how multigene cancer syndrome prediction models compare with syndrome-specific models in assessing risk for individual syndromes such as Lynch syndrome (LS). Our aim was to compare PREMMplus (a 19-gene cancer risk prediction model) with PREMM5 (a LS gene-specific model) for LS identification.

METHODS

We analyzed data from two cohorts of patients undergoing germline testing from a commercial laboratory (n = 12,020) and genetics clinic (n = 6,232) with personal and/or family histories of LS-associated cancer. Individual PREMMplus and PREMM5 scores were calculated for all patients. Using a score cutoff of ≥ 2.5%, we calculated the sensitivity, specificity, positive predictive value, and negative predictive value (NPV) for identifying LS with each model. Overall ability to discriminate LS carriers from noncarriers was measured using receiver operating characteristic (ROC)-AUC.

RESULTS

PREMMplus had higher sensitivity than PREMM5 in the laboratory- (63.7% [95% CI, 57.0 to 70.0] v 89.2% [95% CI, 84.4 to 93.0]) and clinic-based cohorts (60.8% [95% CI, 52.7 to 68.4] v 90.5% [95% CI, 84.8 to 94.6]). NPV was ≥98.8% for both models in both cohorts. PREMM5 had superior discriminatory capacity to PREMMplus in the laboratory- (ROC-AUC, 0.81 [95% CI, 0.77 to 0.84] v 0.71 [95% CI, 0.67 to 0.75]) and clinic-based cohorts (ROC-AUC, 0.79 [95% CI, 0.75 to 0.84] v 0.68 [95% CI, 0.64 to 0.73]).

CONCLUSION

Both PREMM5 and PREMMplus demonstrated high NPVs (>98%) in LS discrimination across all patient cohorts, and both models may be used to identify individuals at risk of LS. The choice of which model to use can be based on the goals of risk assessment and patient population.

The Evolving Role of Genomics in Colorectal Cancer

Approximately 75% of colorectal cancers (CRCs) harbour an identifiable driver mutation, 5% of which are heritable. These drivers have recognised implications for prognosis and therapy selection. In addition, potential germline mutations require investigations to inform testing of relatives, as well as surveillance for other malignancies. With increasing numbers of targeted drugs being approved, judicious testing is required to ensure sufficient tumour sample is available for testing and at the right point in the cancer pathway. Liquid biopsy with circulating tumour DNA (ctDNA) in the blood presents an exciting adjunct to tumour tissue testing for molecular drivers, as well as escalation and de-escalation of therapy. Here, we review the most frequent molecular alterations in CRC, how genomic testing should be integrated into the treatment pathway for CRC, and sources of further education.

Gynecological Insights into Lynch Syndrome-A Comprehensive Review of Cancer Screening and Prevention

Lynch syndrome, one of the most common genetic syndromes predisposing to cancer, is associated with a series of malignant conditions, among which the most frequent is colorectal cancer, but gynecologic cancers (especially endometrial) are also quite common. Despite the significant progress made in understanding this condition over time, there are still aspects in managing this condition that have not demonstrated clear benefits. This article aims to summarize the recommendations of international societies and present the latest developments in managing Lynch syndrome, focusing on gynecologic cancer screening and possible prevention strategies. Advances in genetic testing procedures and discoveries related to the association between oncological pathology frequency and the affected pathogenic variant type will probably lead to personalized medicine focused on the individual patient in the coming years. Although various screening methods for gynecological cancers in patients with Lynch syndrome have been used over time, they have not shown significant survival benefits. This highlights the need for studying and implementing new screening and diagnostic methods, which have been under investigation in recent years and are mentioned in this article.

Uptake of Aspirin Chemoprevention in Patients With Lynch Syndrome

PURPOSE

Individuals with Lynch syndrome (LS) are at a high lifetime risk of colorectal cancer (CRC) and other cancers. Aspirin (ASA), a nonsteroidal anti-inflammatory drug (NSAID), has proven chemopreventive benefits in LS, with the CAPP2 randomized double-blind placebo-controlled trial demonstrating a 60% relative risk reduction for CRC among participants who adhered to ASA for 2 years or more. This study sought to characterize uptake of ASA/NSAIDs among individuals with LS and to understand factors associated with use.

METHODS

Individuals with LS were invited (June 2020-August 2022) to complete a one-time electronic survey about LS screening behaviors, uptake of ASA/NSAIDs, and current/emerging cancer prevention options. Participants were recruited from the Fox Chase Cancer Center (FCCC) Risk Assessment Program Registry and through a research invitation posted to two patient-facing LS advocacy websites.

RESULTS

Two hundred and ninety-six participants completed the survey including 116 (39.2%) from FCCC and 180 (60.8%) recruited via the Internet, including 14.9% non-US based individuals. Uptake of regular ASA or NSAIDs was modest at 34.8% and was even lower (25.7%) when focusing on individuals taking ASA or NSAIDs solely for chemoprevention of LS. More than half (55%) were taking <100 mg ASA daily. In multivariable modeling, lower perceived threat of LS (odds ratio [OR], 0.84 [95% CI, 0.72 to 0.98]), lower concern for side effects (OR, 0.86 [95% CI, 0.76 to 0.99]), and higher likelihood of recommending ASA/NSAIDs to family or a friend were all associated with ASA/NSAIDs use (OR, 1.70 [95% CI, 1.37 to 2.10]).

CONCLUSION

Uptake of ASA/NSAIDs chemoprevention is modest among individuals with LS. Patient perceptions of the pros and cons of ASA, more so than demographic and disease-related factors, were associated with chemoprevention uptake.

Clinical Updates and Surveillance Recommendations for DNA Replication Repair Deficiency Syndromes in Children and Young Adults

Replication repair deficiency (RRD) is a pan-cancer mechanism characterized by abnormalities in the DNA mismatch repair (MMR) system due to pathogenic variants in the PMS2, MSH6, MSH2, or MLH1 genes, and/or in the polymerase-proofreading genes POLE and POLD1. RRD predisposition syndromes (constitutional MMR deficiency, Lynch, and polymerase proofreading-associated polyposis) share overlapping phenotypic and biological characteristics. Moreover, cancers stemming from germline defects of one mechanism can acquire somatic defects in another, leading to complete RRD. Here we describe the recent advances in the diagnostics, surveillance, and clinical management for children with RRD syndromes. For patients with constitutional MMR deficiency, new data combining clinical insights and cancer genomics have revealed genotype-phenotype associations and helped in the development of novel functional assays, diagnostic guidelines, and surveillance recommendations. Recognition of non-gastrointestinal/genitourinary malignancies, particularly aggressive brain tumors, in select children with Lynch and polymerase proofreading-associated polyposis syndromes harboring an RRD biology have led to new management considerations. Additionally, universal hypermutation and microsatellite instability have allowed immunotherapy to be a paradigm shift in the treatment of RRD cancers independent of their germline etiology. These advances have also stimulated a need for expert recommendations about genetic counseling for these patients and their families. Future collaborative work will focus on newer technologies such as quantitative measurement of circulating tumor DNA and functional genomics to tailor surveillance and clinical care, improving immune surveillance; develop prevention strategies; and deliver these novel discoveries to resource-limited settings to maximize benefits for patients globally.

Successful Surveillance Using Endometrial Cytology in a Woman With Lynch Syndrome

Lynch syndrome (LS) results from pathogenic variants in mismatch repair genes and is the most common hereditary cancer syndrome. Some guidelines or studies recommend restricting screening according to endometrial cancer (EC) using endometrial biopsy. The pooled sensitivity and specificity of endometrial cytology for detecting endometrial atypical hyperplasia or cancer have been reported to be as high as the pooled sensitivity and specificity of endometrial biopsy. We conduct transvaginal ultrasound and endometrial cytology in women with LS every six months as surveillance for gynecological malignancy. Through this surveillance program, we can detect early-stage EC in women with LS. Here, we report the case of a patient with stage IA EC detected by endometrial cytology and treated completely. The patient was a 47-year-old woman under surveillance for gynecological malignancy. She was diagnosed as having LS with a germline pathogenic variant in MSH6 after surgery for rectal cancer. Thereafter, gynecological surveillance was started. She had regular menstruation and never experienced atypical genital bleeding. However, her cytopathological findings indicated grade 1 endometrial carcinoma. Endometrial biopsy was performed and endometrial carcinoma was confirmed pathologically. A laparoscopic modified radical hysterectomy with bilateral salpingo-oophorectomy was performed. The resected specimen was reviewed pathologically, and the tumor was finally diagnosed as grade 1 endometrioid carcinoma confined to the endometrium without lymphovascular space invasion. She has remained asymptomatic and free of cancer for five years without any adjuvant therapy. We achieved successful surveillance using endometrial cytology. Endometrial cytology could replace endometrial biopsy as a screening tool for EC.

Clinical implications of the family history in patients with lung cancer: a systematic review of the literature and a new cross-sectional/prospective study design (FAHIC: lung)

Compared to other malignancies, few studies have investigated the role of family history of cancer (FHC) in patients with lung cancer, yielding largely heterogeneous results. We performed a systematic literature review in accordance with PRISMA guidelines, searching the PubMed and Scopus databases from their inception to November 25, 2023, to identify studies reporting on the role of FHC in patients with lung cancer. A total of 53 articles were included, most with a retrospective design and encompassing a variety of geographical areas and ethnicities.Thirty studies (56.6%) assessed patients with non-small cell lung cancer (NSCLC), while 17 studies (32.1%) assessed patients with mixed histologies. Overall, the rates of FHC ranged from 8.3 to 68.9%, and the rates of family history of lung cancer ranged from 2 to 46.8%. Twenty-seven studies investigated FHC as a potential risk factor for lung cancer, with more than half reporting an increased risk for subjects with FHC. Five studies reported on the potential role of FHC in determining clinical outcomes, and twelve studies examined the relationship between FHC and germline mutations. Notably, only one study reported a significantly increased rate of germline mutations, including ATM, BRCA2, and TP53, for patients with a family history of lung cancer compared to those without, but both groups had a low prevalence of mutations (< 1%).The FAHIC-Lung (NCT06196424) is the first cross-sectional/prospective study specifically developed to identify FHC patterns and within-family clusters of other risk factors, including smoking, to guide patients with NSCLC to systematic genetic counseling. Acknowledging the largely heterogeneous results of our systematic review and considering the clinical implications of detecting pathogenic germline variants (PGVs), the FAHIC-lung study aims to identify patients potentially enriched with PGVs/likely PGVs to direct them to germline screening outside of the research setting.

Selection of Germline Genetic Testing Panels in Patients With Cancer: ASCO Guideline

PURPOSE

To guide use of multigene panels for germline genetic testing for patients with cancer.

METHODS

An ASCO Expert Panel convened to develop recommendations on the basis of a systematic review of guidelines, consensus statements, and studies of germline and somatic genetic testing.

RESULTS

Fifty-two guidelines and consensus statements met eligibility criteria for the primary search; 14 studies were identified for Clinical Question 4.

RECOMMENDATIONS

Patients should have a family history taken and recorded that includes details of cancers in first- and second-degree relatives and the patient's ethnicity. When more than one gene is relevant based on personal and/or family history, multigene panel testing should be offered. When considering what genes to include in the panel, the minimal panel should include the more strongly recommended genes from Table 1 and may include those less strongly recommended. A broader panel may be ordered when the potential benefits are clearly identified, and the potential harms from uncertain results should be mitigated. Patients who meet criteria for germline genetic testing should be offered germline testing regardless of results from tumor testing. Patients who would not normally be offered germline genetic testing based on personal and/or family history criteria but who have a pathogenic or likely pathogenic variant identified by tumor testing in a gene listed in Table 2 under the outlined circumstances should be offered germline testing.Additional information is available at www.asco.org/molecular-testing-and-biomarkers-guidelines.

Colorectal cancer

Despite decreased incidence rates in average-age onset patients in high-income economies, colorectal cancer is the third most diagnosed cancer in the world, with increasing rates in emerging economies. Furthermore, early onset colorectal cancer (age ≤50 years) is of increasing concern globally. Over the past decade, research advances have increased biological knowledge, treatment options, and overall survival rates. The increase in life expectancy is attributed to an increase in effective systemic therapy, improved treatment selection, and expanded locoregional surgical options. Ongoing developments are focused on the role of sphincter preservation, precision oncology for molecular alterations, use of circulating tumour DNA, analysis of the gut microbiome, as well as the role of locoregional strategies for colorectal cancer liver metastases. This overview is to provide a general multidisciplinary perspective of clinical advances in colorectal cancer.

State of the art: Targeting microsatellite instability in gastrointestinal cancers

DNA mismatch repair (MMR) deficiency and the associated microsatellite instability (MSI) phenotype has become a subject of enormous interest in recent years due to the demonstrated efficacy of immune checkpoint inhibitors (ICI) in advanced tumours. Assessing MSI in patients with gastrointestinal tract (GI) cancers is useful to exclude Lynch syndrome, but also to predict benefit for ICI. Following review of the relevant literature, this review article aims to outline the clinicopathologic spectrum of MSI and mismatch repair deficiency (dMMR) in the GI tract, hepatobiliary system and pancreas and discuss the therapeutic consideration in this disease.

Streamlining the diagnostic pathway for Lynch syndrome in colorectal cancer patients: a 10-year experience in a single Italian Cancer Center

BACKGROUND

Universal screening of colorectal cancer (CRC) patients for Lynch syndrome (LS) through MisMatch Repair (MMR) testing is recommended. BRAF V600E mutation and/or MLH1 promoter methylation (Reflex Testing, RefT)generally rule out LS in MLH1-deficient (dMLH1) patients. We estimated the impact of RefTon genetic counseling (GC) and on the diagnostic yield of genetic testing (GT).

METHODS

Overall, 3199 CRC patients were referred to our center between 2011 and 2021. Patients referred until January 2019 (n=2536) underwent universal MMR testing and were termed 'Cohort A'; among patients after February 2019 (n=663), 'Cohort B', RefT was also performed in dMLH1 patients.

RESULTS

Overall, 401/3199 patients (12.5%) were MMR-deficient (dMMR); 312 (77.8%) in cohort A and 89 (22.2%) inB; 346/401 were dMLH1 (86.3%), 262/312 (83.9%) in cohort A and 84/89 (94.3%) in B. In Cohort A, 91/312 (29.1%) dMMR patients were referred to GC, 69/91 (75.8%) were in the dMLH1 group; 57/69 (82.6%) dMLH1 patients underwent GT and 1/57 (1.7%) had LS. In Cohort B, 3/84 dMLH1 patients did not undergo BRAF testing. Three BRAF wt and not hypermethylated of the remaining 81 dMLH1 patients were referred to GC and GT, and one had LS. This diagnostic pathway reduced GC referrals by 96% (78/81) in Cohort B and increased the diagnostic yield of GT by about 20 times.

CONCLUSION

Our findings support RefT in dMLH1 CRC patients within the LS diagnostic pathway, as it reduces the number of GC sessions needed and increases the diagnostic yield of GT.

Hereditary Cancer Syndrome Carriers: Feeling Left in the Corner

OBJECTIVES

There is limited evidence on health promotion interventions in people with hereditary cancer syndromes or on their main sources of support and information. This study aimed to understand these patients' experiences and needs, including their information needs, their views on prevention and mental health, and the support they want from nurses.

METHODS

This qualitative study included 22 people (8 previvors and 14 survivors) with hereditary breast and ovarian syndrome or Lynch syndrome from 10 European countries. Participants underwent individual semi-structured interviews, which were recorded and transcribed for reflexive thematic analysis. The patient and public involvement panel provided input on study design and thematic analysis.

RESULTS

Patient experiences were similar regardless of the country and access to testing and screening. Participants reported receiving little information on the importance of health behaviors for cancer risk and expressed their wish to be followed by cancer professionals. They felt compelled to seek support and information from the internet and patient groups. The main themes identified were: (unmet) informational and support needs, seeing life in a different way, and limitations of health care providers.

CONCLUSIONS

People with hereditary cancer syndromes need professionals to be involved in their long-term management and to provide reliable information. As genomics are increasingly integrated in oncology, the need for professionals to support these populations will increase.

IMPLICATIONS FOR NURSING PRACTICE

Nurses are crucial for promoting self-management and advocating for patient decision-making; however, they need skills and knowledge to do so. There is a need for nurses to get more involved in understanding hereditary cancer syndromes and an opportunity to take the lead in the care of these people.

Deep learning to assess microsatellite instability directly from histopathological whole slide images in endometrial cancer

Molecular classification, particularly microsatellite instability-high (MSI-H), has gained attention for immunotherapy in endometrial cancer (EC). MSI-H is associated with DNA mismatch repair defects and is a crucial treatment predictor. The NCCN guidelines recommend pembrolizumab and nivolumab for advanced or recurrent MSI-H/mismatch repair deficient (dMMR) EC. However, evaluating MSI in all cases is impractical due to time and cost constraints. To overcome this challenge, we present an effective and efficient deep learning-based model designed to accurately and rapidly assess MSI status of EC using H&E-stained whole slide images. Our framework was evaluated on a comprehensive dataset of gigapixel histopathology images of 529 patients from the Cancer Genome Atlas (TCGA). The experimental results have shown that the proposed method achieved excellent performances in assessing MSI status, obtaining remarkably high results with 96%, 94%, 93% and 100% for endometrioid carcinoma G1G2, respectively, and 87%, 84%, 81% and 94% for endometrioid carcinoma G3, in terms of F-measure, accuracy, precision and sensitivity, respectively. Furthermore, the proposed deep learning framework outperforms four state-of-the-art benchmarked methods by a significant margin (p < 0.001) in terms of accuracy, precision, sensitivity and F-measure, respectively. Additionally, a run time analysis demonstrates that the proposed method achieves excellent quantitative results with high efficiency in AI inference time (1.03 seconds per slide), making the proposed framework viable for practical clinical usage. These results highlight the efficacy and efficiency of the proposed model to assess MSI status of EC directly from histopathological slides.

Incidental pathogenic germline alterations detected through liquid biopsy in patients with solid tumors: prevalence, clinical utility and implications

Liquid biopsy, a minimally invasive approach for detecting tumor biomarkers in blood, has emerged as a leading-edge technique in cancer precision medicine. New evidence has shown that liquid biopsies can incidentally detect pathogenic germline variants (PGVs) associated with cancer predisposition, including in patients with a cancer for which genetic testing is not recommended. The ability to detect these incidental PGV in cancer patients through liquid biopsy raises important questions regarding the management of this information and its clinical implications. This incidental identification of PGVs raises concerns about cancer predisposition and the potential impact on patient management, not only in terms of providing access to treatment based on the tumor molecular profiling, but also the management of revealing genetic predisposition in patients and families. Understanding how to interpret this information is essential to ensure proper decision-making and to optimize cancer treatment and prevention strategies. In this review we provide a comprehensive summary of current evidence of incidental PGVs in cancer predisposition genes identified by liquid biopsy in patients with cancer. We critically review the methodological considerations of liquid biopsy as a tool for germline diagnosis, clinical utility and potential implications for cancer prevention, treatment, and research.

Multimodal Treatment of Metastatic Rectal Cancer in a Young Patient: Case Report and Literature Review

Metastatic colorectal cancer requires a multidisciplinary and individualized approach. Herein, we reported the case of a young woman diagnosed with metastatic rectal cancer who received an individualized multimodal treatment strategy that resulted in a remarkable survival. There were several particular aspects of this case, such as the early onset of the disease, the successful use of conversion therapy, the application of liquid biopsy to guide treatment, and the specific nature of the bone metastasis. To offer more insights for navigating such challenges in patients with metastatic colorectal cancer, we have conducted a literature review to find more data related to the particularities of this case. The incidence of early onset colorectal cancer is on the rise. Data suggests that it differs from older-onset colorectal cancer in terms of its pathological, epidemiological, anatomical, metabolic, and biological characteristics. Conversion therapy and surgical intervention provide an opportunity for cure and improve outcomes in metastatic colorectal cancer. It is important to approach each case individually, as every patient with limited liver disease should be considered as a candidate for secondary resection. Moreover, liquid biopsy has an important role in the individualized management of metastatic colorectal cancer patients, as it offers additional information for treatment decisions.

Tumor analysis of MMR genes in Lynch-like syndrome: Challenges associated with results interpretation

BACKGROUND

Up to 70% of suspected Lynch syndrome patients harboring MMR deficient tumors lack identifiable germline pathogenic variants in MMR genes, being referred to as Lynch-like syndrome (LLS). Previous studies have reported biallelic somatic MMR inactivation in a variable range of LLS-associated tumors. Moreover, translating tumor testing results into patient management remains controversial. Our aim is to assess the challenges associated with the implementation of tumoral MMR gene testing in routine workflows.

METHODS

Here, we present the clinical characterization of 229 LLS patients. MMR gene testing was performed in 39 available tumors, and results were analyzed using two variant allele frequency (VAF) thresholds (≥5% and ≥10%).

RESULTS AND DISCUSSION

More biallelic somatic events were identified at VAF ≥ 5% than ≥10% (35.9% vs. 25.6%), although the rate of nonconcordant results regarding immunohistochemical pattern increased (30.8% vs. 20.5%). Interpretation difficulties question the current utility of the identification of MMR somatic hits in the diagnostic algorithm of suspected LS cases.

BRAFV600E immunohistochemistry can reliably substitute BRAF molecular testing in the Lynch syndrome screening algorithm in colorectal cancer

AIMS

The Lynch syndrome (LS) screening algorithm requires BRAF testing as a fundamental step to distinguish sporadic from LS-associated colorectal carcinomas (CRC). BRAF testing by immunohistochemistry (IHC) has shown variable results in the literature. Our aim was to analyse concordance between BRAFV600E IHC and BRAF molecular analysis in a large, mono-institutional CRC whole-slide, case series with laboratory validation.

METHODS AND RESULTS

MisMatch repair (MMR) protein (hMLH1, hPMS2, hMSH2, and hMSH6) and BRAFV600E IHC were performed on all unselected cases of surgically resected CRCs (2018-2023). An in-house validation study for BRAFV600E IHC was performed in order to obtain optimal IHC stains. BRAFVV600E IHC was considered negative (score 0), positive (scores 2-3), and equivocal (score 1). Interobserver differences in BRAFV600E IHC scoring were noted in the first 150 cases prospectively collected. Nine-hundred and ninety CRCs cases (830 proficient (p)MMR/160 deficient (d)MMR) were included and all cases performed BRAFV600E IHC (BRAFV600E IHC-positive 13.5% of all series; 66.3% dMMR cases; 3.4% pMMR cases), while 333 also went to BRAF mutation analysis. Optimal agreement in IHC scoring between pathologists (P < 0.0001) was seen; concordance between BRAFV600E IHC and BRAF molecular analysis was extremely high (sensitivity 99.1%, specificity 99.5%; PPV 99.1%, and NPV 99.5%). Discordant cases were reevaluated; 1 score 3 + IHC/wildtype case was an interpretation error and one score 0 IHC/mutated case was related to heterogenous BRAFV600E IHC expression. Among the 12 IHC-equivocal score 1+ cases (which require BRAF molecular analysis), three were BRAF-mutated and nine BRAF-wildtype.

CONCLUSION

BRAFV600E IHC can be used as a reliable surrogate of molecular testing after stringent in-house validation.

Use of multi-gene panels in patients at high risk of hereditary digestive cancer: position statement of AEG, SEOM, AEGH and IMPaCT-GENÓMICA consortium

This position statement, sponsored by the Asociación Española de Gastroenterología, the Sociedad Española de Oncología Médica, the Asociación Española de Genética Humana and the IMPaCT-Genómica Consortium aims to establish recommendations for use of multi-gene panel testing in patients at high risk of hereditary gastrointestinal and pancreatic cancer. To rate the quality of the evidence and the levels of recommendation, we used the methodology based on the GRADE system (Grading of Recommendations Assessment, Development and Evaluation). We reached a consensus among experts using a Delphi method. The document includes recommendations on clinical scenarios where multi-gene panel testing is recommended in colorectal cancer, polyposis syndromes, gastric and pancreatic cancer, as well as the genes to be considered in each clinical scenario. Recommendations on the evaluation of mosaicisms, counseling strategies in the absence of an index subject and, finally, constitutional analysis after identification of pathogenic tumor variants are also made.

Gastric and duodenal cancer in individuals with Lynch syndrome: a nationwide cohort study

Background

Lynch syndrome increases the risk of gastric cancer (GC) and duodenal cancer (DC), particularly in individuals with MLH1 and MSH2 pathogenic variants (PVs). To provide further insight into whether, and from what age, esophagogastroduodenoscopy (EGD) surveillance may be beneficial, we evaluated the cumulative incidence and tumour characteristics of GC and DC in a large nationwide cohort of Dutch individuals with LS.

Methods

For this retrospective nationwide cohort study, clinical data of individuals with LS registered at the Dutch Hereditary Cancer Registry were matched with pathology reports filed by the Dutch Pathology registry. All individuals registered between Jan 1, 1989 and Dec 31, 2021 with proven or putative PVs in one of the mismatch repair genes were included. Cumulative incidences of GC and DC were estimated for high-risk (MLH1, MSH2 and EpCAM) and low-risk (MSH6 and PMS2) PVs using competing risk methodology (Fine and Gray method) with death due to other causes as competing risk.

Findings

Among 1002 individuals with high-risk and 765 individuals with low-risk PVs, 29 GCs (1.6%) and 39 DCs (2.2%) were diagnosed. Cumulative incidence of GC and DC under the age of 50 was very low (≤1%) for all individuals. At age 70 and 75, cumulative incidence of GC was 3% [95% CI 1%-5%] and 5% [3%-8%] for high-risk PVs and 1% [0%-2%] and 1% [0%-2%] for low-risk PVs (p = 0.006). For DC, cumulative incidence at age 70 and 75 was 5% [3%-7%] and 6% [3%-8%] in high-risk, 1% [0%-1%] and 2% [0%-4%] in low-risk PVs, respectively (p = 0.01). Primary tumour resection was performed in 62% (18/29) of GCs and 77% (30/39) of DC cases. Early-stage GC, defined as TNM stage I, was found in 32% (9/28) of GCs. Early-stage DC, defined as TNM stage I-IIa, was found in 39% (14/36) of DCs.

Interpretation

Individuals with MLH1, MSH2, and EpCAM PVs have an increased risk of developing GC and DC at the age of 70 years, but this risk is very low before the age of 50 years. The age of onset of surveillance, the yield of GC and DC during EGD surveillance, and its cost-effectiveness should be subject of future studies.

Funding

None.

Real-World Data on Institutional Implementation of Screening for Mismatch Repair Deficiency and Lynch Syndrome in Endometrial Cancer Patients

Lynch syndrome is an inherited tumor syndrome caused by a pathogenic germline variant in DNA mismatch repair genes. As the leading cause of hereditary endometrial cancer, international guidelines recommend universal screening in women with endometrial cancer. However, testing for Lynch syndrome is not yet well established in clinical practice. The aim of this study was to evaluate adherence to our Lynch syndrome screening algorithm. A retrospective, single-center cohort study was conducted of all endometrial cancer patients undergoing surgical treatment at the Bern University Hospital, Switzerland, between 2017 and 2022. Adherence to immunohistochemical analysis of mismatch repair status, and, if indicated, to MLH1 promoter hypermethylation and to genetic counseling and testing was assessed. Of all 331 endometrial cancer patients, 102 (30.8%) were mismatch repair-deficient and 3 (0.9%) patients were diagnosed with Lynch syndrome. Overall screening adherence was 78.2%, with a notable improvement over the six years from 61.4% to 90.6%. A major reason for non-adherence was lack of provider recommendation for testing, with advanced patient age as a potential patient risk factor. Simplification of the algorithm through standardized reflex screening was recommended to provide optimal medical care for those affected and to allow for cascading testing of at-risk relatives.

Impact of genetic counseling strategy on diagnostic yield and workload for genome-sequencing-based tumor diagnostics

PURPOSE

Genome sequencing (GS) enables comprehensive molecular analysis of tumors and identification of hereditary cancer predisposition. According to guidelines, directly determining pathogenic germline variants (PGVs) requires pretest genetic counseling, which is cost-ineffective. Referral for genetic counseling based on tumor variants alone could miss relevant PGVs and/or result in unnecessary referrals.

METHODS

We validated GS for detection of germline variants and simulated 3 strategies using paired tumor-normal GS data of 937 metastatic patients. In strategy-1, genetic counseling before tumor testing allowed direct PGV analysis. In strategy-2 and -3, germline testing and referral for post-test genetic counseling is based on tumor variants using Dutch (strategy-2) or Europen Society for Medical Oncology (ESMO) Precision Medicine Working Group (strategy-3) guidelines.

RESULTS

In strategy-1, PGVs would be detected in 50 patients (number-needed-to counsel; NTC = 18.7). In strategy-2, 86 patients would have been referred for genetic counseling and 43 would have PGVs (NTC = 2). In strategy-3, 94 patients would have been referred for genetic counseling and 32 would have PGVs (NTC = 2.9). Hence, 43 and 62 patients, respectively, were unnecessarily referred based on a somatic variant.

CONCLUSION

Both post-tumor test counseling strategies (2 and 3) had significantly lower NTC, and strategy-2 had the highest PGV yield. Combining pre-tumor test mainstreaming and post-tumor test counseling may maximize the clinically relevant PGV yield and minimize unnecessary referrals.

Case report: Efficacy of immunotherapy as conversion therapy in dMMR/MSI-H colorectal cancer: a case series and review of the literature

Immunotherapy has demonstrated a role in the therapeutic landscape of a small subset of patients with colorectal carcinoma (CRC) that harbor a microsatellite instability (MSI-H) status due to a deficient DNA mismatch repair (dMMR) system. The remarkable responses to immune checkpoint inhibitors (ICIs) are now being tested in the neoadjuvant setting in localized CRC, where the dMMR/MSI-H status can be found in up to 15% of patients, with remarkable results obtained in NICHE2 and 3 trials, among others. This case series aims to report our experience at a tertiary center and provide a comprehensive analysis of the possible questions and challenges to overcome if ICIs were established as standard of care in a neoadjuvant setting, as well as the potential role they may have as conversion therapy not only in locoregional advanced CRC but also in oligometastatic disease.

Endoscopic surveillance for familial intestinal gastric cancer in low-incidence areas: An effective strategy

While clinical practice guidelines for hereditary diffuse gastric cancer are well established, there is no consensus on the approach for familial intestinal gastric cancer (FIGC). In low-incidence gastric cancer (GC) areas such as the United States or most European countries, there are no evidence-based recommendations on endoscopic assessment in FIGC families. We aim to describe the yield of GC surveillance in these families, and to identify epidemiological risk factors for the development of GC and its precursor lesions. This is a multicenter observational study involving nine tertiary Spanish hospitals, in which all individuals fulfilling FIGC criteria who underwent endoscopic surveillance were included between 1991 and 2020. Forty-one healthy individuals of 31 families were recruited. The median number of upper gastrointestinal endoscopies per individual was 3 (interquartile range, IQR, 1-4). The median interval time between tests was 2 years (IQR 1.5-2.5), and the median follow-up was 9 years (IQR 3-14.5). In 18 (43.9%) subjects, a precursor lesion of GC was found during follow-up, and in 2 (4.9%), an early GC was identified, in which curative treatment was offered. Helicobacter pylori (Hp) infection proved to be independently associated with an increased risk of developing precursor lesions or GC, adjusted by age, gender and follow-up, with an Odds Ratio of 6.443 (1.36-30.6, P value .019). We present the first outcomes that support endoscopic surveillance with biopsies and detection of Hp in FIGC families, although the periodicity has yet to be defined.

Current status and perspectives of genetic testing in gastrointestinal cancer (Review)

Genetic testing has become widespread in daily medical care for gastrointestinal (GI) cancers. However, unlike breast cancer and non-small cell lung cancer, in which personalized medicine targeting various driver genes is standardized, the incidence of targeted gene abnormalities in GI cancers is low. Nevertheless, such abnormalities may be linked to therapeutic agents and the further development of therapeutic agents for personalized medicine for GI cancers is desired. A liquid biopsy is of great benefit in offering clinical decision support, in applications such as GI cancer screening, surgical interventions, monitoring disease status and enhancing patient survival outcomes, all of which would contribute to personalized medicine. Germline genetic testing is required for several types of GI cancer, which shows clinical indications of hereditary predisposition. The increasing use of multigene panel testing has redefined gene-cancer associations, and consequently the estimate of cancer risk that vary from low to high penetrance. Comprehensive genetic testing can enable the detection of novel treatment targets and the discovery of undefined multiple diagnostic/predictive markers, which may enhance the molecular-level understanding of GI cancers. Genetic testing can also aid the design of more appropriate and adequate genomic-driven therapies for patients who may benefit from other standardized therapeutic methods.

Opportunistic genetic screening increases the diagnostic yield and is medically valuable for care of patients and their relatives with hereditary cancer

BACKGROUND

Multigene panel testing by next-generation sequencing (MGP-NGS) enables the detection of germline pathogenic or likely pathogenic variants (PVs/LPVs) in genes beyond those associated with a certain cancer phenotype. Opportunistic genetic screening based on MGP-NGS in patients with suspicion of hereditary cancer reveals these incidental findings (IFs).

METHODS

MGP-NGS was performed in patients who fulfilled the clinical criteria to undergo genetic testing according to the Catalan Health Service guidelines. Variants were classified following the American College of Medical Genetics and Genomics-Association for Molecular Pathology guidelines and the Cancer Variant Interpretation Group UK guidelines.

RESULTS

IFs were identified in 10 (1.22%) of the 817 patients who underwent MGP-NGS. The mean age at cancer diagnosis was 49.4±9.5 years. Three IFs (30.0%) were detected in PMS2, two (20.0%) in ATM and TP53 and one (10.0%) in MSH6, NTHL1 and VHL. Seven (70.0%) IFs were single-nucleotide substitutions, two (20.0%) were deletions and one (10.0%) was a duplication. Three (30.0) IFs were located in intronic regions, three (30.3%) were nonsense, two (20.0%) were frameshift and two (20.0%) were missense variations. Six (60.0%) IFs were classified as PVs and four (40.0%) as LPVs.

CONCLUSIONS

Opportunistic genetic screening increased the diagnostic yield by 1.22% in our cohort. Most of the identified IFs were present in clinically actionable genes (n=7; 70.0%), providing these families with an opportunity to join cancer early detection programmes, as well as secondary cancer prevention. IFs might facilitate the diagnosis of asymptomatic individuals and the early management of cancer once it develops.

Endoscopic Approach to Duodenal Adenomas in Familial Adenomatous Polyposis: A Retrospective Cohort

Introduction

Over 90% of the patients with familial adenomatous polyposis (FAP) will develop duodenal adenomas.

Aim

The aim of this study was to evaluate the effectiveness and safety of endoscopic excision of large duodenal adenomas in FAP patients.

Methods

All FAP patients from a familial risk clinic submitted to endoscopic therapy for duodenal adenomas ≥10 mm between January 2010 and February 2021 were included.

Results

From 151 FAP families, 22 patients (50 lesions) were included: 54.5% female; median follow-up 8.5 (IQR: 5.8-12.3) years after the first endoscopy. First therapeutic endoscopy occurred at a median age of 41.0 years (IQR: 33.0-58.2). Repeat therapeutic endoscopy was required in 54.5% of patients. Median size of the largest adenoma was 15 mm (IQR: 10-18 mm); resection was piecemeal in 63.1% and en bloc in the remaining. In 2 cases, the resection was incomplete (fibrosis due to previous resection and difficult positioning). Complications occurred in 6.3% of the resected lesions (4 patients): 2 immediate (bleeding, perforation); 4 in the first week (1 bleeding, 2 mild pancreatitis, 1 perforation requiring surgery; the latter two after ampullectomy). Histology revealed low-grade dysplasia adenomas in 90.1%; no adenocarcinomas were found. One patient with Spigelman stage IV disease not amenable to endoscopic control underwent elective duodenopancreatectomy (without duodenal cancer).

Conclusion

Endoscopic surveillance and treatment of duodenal adenomas in FAP patients was safe and effective in the prevention of duodenal cancer.

MUTYH-associated polyposis: Is it time to change upper gastrointestinal surveillance? A single-center case series and a literature overview

BACKGROUND

The presence of Spigelman stage (SS) IV duodenal polyposis is considered the most significant risk factor for duodenal cancer in patients with MUTYH-associated polyposis (MAP). However, advanced SS disease is rarely reported in MAP patients, and no clear recommendations on small bowel (SB) surveillance have been proposed in this patient setting.

AIM

To research more because that case reports of duodenal cancers in MAP suggest that they may develop in the absence of advanced benign SS disease and often involve the distal portion of the duodenum.

METHODS

We describe a series of MAP patients followed up at the Regina Elena National Cancer Institute of Rome (Italy). A literature overview on previously reported SB cancers in MAP is also provided.

RESULTS

We identified two (6%) SB adenocarcinomas with no previous history of duodenal polyposis. Our observations, supported by literature evidence, suggest that the formula for staging duodenal polyposis and predicting risk factors for distal duodenum and jejunal cancer may need to be adjusted to take this into account rather than focusing solely on the presence or absence of SS IV disease.

CONCLUSION

Our study emphasizes the need for further studies to define appropriate upper gastrointestinal surveillance programs in MAP patients.

Impact of formalin fixation on mismatch repair protein evaluation by immunohistochemistry

Mismatch repair/microsatellite instability (MMR/MSI) status in colorectal cancer (CRC) has become fundamental as a diagnostic, prognostic, and predictive factor. MMR immunohistochemistry (IHC) is considered a simple and reliable approach; however, its effectiveness depends on pre-analytic factors. Aim of this study was to investigate the impact of different fixation times/protocols on MMR protein IHC quality. Left over tissue from surgically resected CRC samples (cold ischemia time < 30 min) where fixed as follows: standard formalin fixation (24-48 h); hypo-fixation (<20 h); hyper-fixation (>90 h); cold (4°C) fixation (24-48 h); standard fixation for small sample size (0.5×0.5 cm). Samples for each group were collected from 30 resected CRC and the following parameters were evaluated on 600 immunohistochemical stains: intensity of expression; patchiness of staining; presence of central artefact. Forty-six immunoreactions were inadequate (score 0 intensity), the majority regarding MLH1 or PMS2 in the hypo-fixation group (47.8%), followed by the hyper-fixation group (28.1%); cold formalin fixation showed the least inadequate cases. Patchiness and central artefact were more frequent in hypo-fixation and standard fixation group compared to the others. MLH1 (closely followed by PMS2) performed worse with regard to immunostaining intensity (p=0.0002) in the standard and in the hypo-fixation group (p< 0.00001). Using a small sample size improved patchiness/central artefacts. This is the first study specifically created to evaluate the impact of fixation on MMR protein IHC, showing that both formalin hypo- and hyper-fixation can cause problems; 24-h formalin fixation as well as cold (4°C) formalin fixation are recommended for successful IHC MMR evaluation.

Methylated DNA Markers for Sporadic Colorectal and Endometrial Cancer Are Strongly Associated with Lynch Syndrome Cancers

Lynch syndrome (LS) markedly increases risks of colorectal and endometrial cancers. Early detection biomarkers for LS cancers could reduce the needs for invasive screening and surgical prophylaxis.To validate a panel of methylated DNA markers (MDM) previously identified in sporadic colorectal cancer and endometrial cancer for discrimination of these cancers in LS.In a case-control design, previously identified MDMs for the detection of colorectal cancer and endometrial cancer were assayed by qMSP on tissue-extracted DNA. Results were normalized to ACTB values within each sample. Least absolute shrinkage and selection operator models to classify colorectal cancer and endometrial cancer were trained on sporadic cases and controls and then applied to classify colorectal cancer and endometrial cancer, in those with LS, and cross-validated.We identified colorectal cancer cases (23 with LS, 48 sporadic), colorectal controls (32 LS, 48 sporadic), endometrial cancer cases (30 LS, 48 sporadic), and endometrial controls (29 LS, 37 sporadic). A 3-MDM panel (LASS4, LRRC4, and PPP2R5C) classified LS-CRC from LS controls with an AUC of 0.92 (0.84-0.99); results were similar for sporadic colorectal cancer. A 6-MDM panel (SFMBT2, MPZ, CYTH2, DIDO1, chr10.4479, and EMX2OS) discriminated LS-EC from LS controls with an AUC of 0.92 (0.83-1.0); the AUC for sporadic endometrial cancer versus sporadic controls was nominally higher, 0.99 (0.96-1.0).MDMs previously identified in sporadic endometrial cancer and colorectal cancer discriminate between endometrial cancer and benign endometrium and colorectal cancer and benign colorectum in LS. This supports the inclusion of patients with LS within future prospective clinical trials evaluating endometrial cancer and colorectal cancer MDMs and may provide a new avenue for cancer screening or surveillance in this high-risk population.

PREVENTION RELEVANCE

Lynch syndrome (LS) markedly increases risks of colorectal and endometrial cancers. Early detection biomarkers for LS cancers could reduce the needs for invasive screening and surgery. Methylated DNA markers previously identified in sporadic endometrial cancer and colorectal cancer discriminate between benign and cancer tissue in LS.

Synchronous and metachronous primary colorectal cancers with concordant and discordant mismatch repair status

Multiple primary colorectal carcinomas (CRCs) synchronous, when detected approximately at the same time, or metachronous, when a significant amount of time has elapsed between diagnoses can show both mismatch repair (MMR) status concordance and discordance between primary tumors. The aim was to evaluate the MMR status of a monoinstitutional, retrospective cohort of synchronous and metachronous CRCs, with a focus on the frequency of cases with discordant MMR status, and explore the MMR status of metastatic nodal deposits. All synchronous and metachronous CRCs diagnosed in our institution between 2011 and 2023 were collected. Clinicopathologic characteristics were evaluated, including MMR status of all CRCs, BRAF mutation, and MLH1 promoter methylation analyses. MMR status discordant cases were further analyzed, and MMR testing was performed on nodal metastases. Of 3671 patients, 107 (2.9%) had multiple CRCs (94 synchronous and 13 metachronous; total number of CRCs 220). Sixty CRCs were MMR deficient (dMMR) (27.3%), and most were right-sided and high-grade and showed special histologic features (P < .00001). Ninety-three patients showed intertumoral MMR concordance: 70 (65.4%) with MMR-proficient (pMMR) CRCs, and 23 (21.5%) were dMMR. Fourteen patients (13.1%) showed intertumoral MMR discordance (at least one dMMR and one pMMR), and in 5 patients, nodal metastases were present: 2 patients harbored metastases only from their pMMR cancer, 2 only from their dMMR cancer, and in 1 patient both pMMR and dMMR metastases were present. In conclusion, all multiple primary CRCs should be analyzed for MMR status as discordant MMR is possible as well as discordant metastatic nodal deposits, and this may be important for patient management.

PATHOLOGICAL SIGNIFICANCE OF CDH1/E-CADHERIN GERMLINE SEQUENCE VARIANTS IN BREAST CANCER PATIENTS

BACKGROUND

Germline alterations of the CDH1 (E-cadherin) tumor suppressor gene have been reported in several epithelial malignancies like hereditary diffuse gastric cancer and lobular breast cancer. E-cadherin plays a central role in proliferation, maintenance of cell-to-cell adhesion, polarity, and epithelial-mesenchymal transition of tissue cells. It is necessary to analyze the impact of the CDH1 germline sequence variants on protein and predict its clinical significance in breast cancer (BC) progression. The aim of the current study was to evaluate the impact and association of CDH1 gene potentially pathogenic variants/likely pathogenic variants (PVs/LPVs) with the initiation and progression of BC.

MATERIALS AND METHODS

In this study, the clinical data of 200 BC patients have been analyzed based on the type of BC, age, grade, stage, hormonal status, and risk factors. Blood samples from 50 healthy donors were used as a control. Furthermore, CDH1 gene molecular analysis, along with in silico analysis, was provided to assess the invasiveness and progression of BC caused by the E-cadherin protein.

RESULTS

Four variants were identified by genetic screening within the CDH1 gene that included variations in exons 7, 8, 10, 11, and 13. Exon 10 had splice site mutation at position c.1337C>A, affecting the protein structure. In exon 11, there was an insertion of T base at position 1669, resulting in truncated protein compared to a normal one that can lead to the disease-causing non- sense-mediated decay and exon 13 variant c.2076T>C has already known polymorphism. In silico analysis of CDH1 showed the presence of the different variants that indicated the overall disruption of protein structure and function.

CONCLUSIONS

The further functional analysis of these variants and their association with BC can be ensured by increasing the sample size and in vivo studies using mouse models.

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.

Evaluating mismatch repair deficiency in colorectal cancer biopsy specimens

Mismatch repair (MMR) testing on all new cases of colorectal cancer (CRC) has customarily been preferably performed on surgical specimens, as more tissue is available; however, new clinical trials for the use of immune checkpoint inhibitors in the neoadjuvant setting require MMR testing on biopsy samples. This study aims at identifying advantages, disadvantages and any potential pitfalls in MMR evaluation on biopsy tissue and how to cope with them. The study is prospective-retrospective, recruiting 141 biopsies (86 proficient (p)MMR and 55 deficient (d)MMR) and 97 paired surgical specimens (48 pMMR; 49 dMMR). In biopsy specimens, a high number of indeterminate stains was observed, in particular for MLH1 (31 cases, 56.4%). The main reasons were a punctate nuclear expression of MLH1, relatively weak MLH1 nuclear expression compared to internal controls, or both (making MLH1 loss difficult to interpret), which was solved by reducing primary incubation times for MLH1. A mean of  ≥ 5 biopsies had adequate immunostains, compared to ≤ 3 biopsies in inadequate cases. Conversely, surgical specimens rarely suffered from indeterminate reactions, while weaker staining intensity (p < 0.007) for MLH1 and PMS2 and increased patchiness grade (p < 0.0001) were seen. Central artefacts were almost exclusive to surgical specimens. MMR status classification was possible in 92/97 matched biopsy/resection specimen cases, and all of these were concordant (47 pMMR and 45 dMMR). Evaluation of MMR status on CRC biopsy samples is feasible, if pitfalls in interpretation are known, making laboratory-specific appropriate staining protocols fundamental for high-quality diagnoses.

Identification of a novel CNV at the APC gene in a Chinese family with familial adenomatous polyposis

Introduction: Familial adenomatous polyposis (FAP) is the second most commonly inherited colorectal cancer (CRC) predisposition caused by germline mutations within the adenomatous polyposis coli (APC) gene. The molecular defects and clinical manifestations of two FAP families were analyzed, and individual prevention strategies suitable for mutation carriers in different families were proposed. Methods and results: The pathogenic gene mutations were identified among the two families using whole-exome sequencing and verified with Sanger sequencing or quantitative polymerase chain reaction (qPCR). One novel (GRCh37:Chr5: 112145676-112174368, del, 28,692 bp) and a known (c.C847T:p.R283X) mutation in the APC gene were pathogenic mutations for FAP, according to the sequencing data and tumorigenesis pattern among the family members. The two mutations led to a premature translational stop signal, synthesizing an absent or disrupted protein product. Conclusion: Our findings expand the known germline mutation spectrum of the APC gene among the Chinese population. This reaffirms the importance of genetic testing in FAP. Genetic consultation and regular follow-ups are necessary for the individualized treatment of cancer-afflicted families with APC expression deficiency. Additional work is required to develop safe and effective chemotherapy and immunotherapy for FAP based on the mutation type.

Early-Onset Colorectal Cancer: Current Insights

Over the past decade, the incidence of colorectal cancer has increased in individuals under the age of 50 years. Meanwhile, the incidence has gradually decreased in the older population. As described herein, we reviewed the available literature to summarize the current landscape of early-onset colorectal cancer, including risk factors, clinicopathological presentation, genetic makeup of patients, and management. Currently, early-onset colorectal cancer is treated similarly as late-onset colorectal cancer, yet the available literature shows that early-onset colorectal cancer is more aggressive and different, and this remains a significant unmet need. A detailed understanding of early-onset colorectal cancer is needed to identify risk factors for the increased incidence and tailor treatments accordingly.