The Psychosocial Impact of Undergoing Prophylactic Total Gastrectomy (PTG) to Manage the Risk of Hereditary Diffuse Gastric Cancer (HDGC)

Costs of Cancer Prevention: Physical and Psychosocial Sequelae of Risk-Reducing Total Gastrectomy

PURPOSE

Risk-reducing surgery for cancer prevention in solid tumors is a pressing clinical topic because of the increasing availability of germline genetic testing. We examined the short- and long-term outcomes of risk-reducing total gastrectomy (RRTG) and its lesser-known impacts on health-related quality of life (QOL) in individuals with hereditary diffuse gastric cancer syndrome.

METHODS

Individuals who underwent RRTG as part of a single-institution natural history study of hereditary gastric cancers were examined. Clinicopathologic details, acute and chronic operative morbidity, and health-related QOL were assessed. Validated questionnaires were used to determine QOL scores and psycho-social-spiritual measures of healing.

RESULTS

One hundred twenty-six individuals underwent RRTG because of a pathogenic or likely pathogenic germline CDH1 variant between October 2017 and December 2021. Most patients (87.3%; 110/126) had pT1aN0 gastric carcinoma with signet ring cell features on final pathology. Acute (<30 days) postoperative major morbidity was low (5.6%; 7/126) and nearly all patients (98.4%) lost weight after total gastrectomy. At 2 years after gastrectomy, 94% (64/68) of patients exhibited at least one chronic complication (ie, bile reflux, dysphagia, and micronutrient deficiency). Occupation change (23.5%), divorce (3%), and alcohol dependence (1.5%) were life-altering consequences attributed to total gastrectomy by some patients. In patients with a median follow-up of 24 months, QOL scores decreased at 1 month after gastrectomy and returned to baseline by 6-12 months.

CONCLUSION

RRTG is associated with life-changing adverse events that should be discussed when counseling patients with CDH1 variants about gastric cancer prevention. The risks of cancer-prevention surgery should not only be judged in the context of likelihood of death due to disease if left untreated, but also based on the real consequences of organ removal.

A Systematic Review on Clinical and Health-Related Quality of Life Outcomes following Total Gastrectomy in Patients with Hereditary Diffuse Gastric Cancer

Hereditary diffuse gastric cancer (HDGC) is an autosomal-dominant syndrome associated with early onset diffuse gastric cancer. Definitive treatment is prophylactic total gastrectomy (PTG) associated with significant morbidity. Studies published from January 2000 to December 2022 reporting clinical, histopathological or health-related quality of life outcomes in HDGC patients undergoing PTG were identified. The study quality was assessed by the "Newcastle-Ottawa scale". Of the 257 articles screened, 21 were selected. A total of 353 patients were examined in 15 studies that reported surgical outcomes. The median age was 42 years old. The median major complication and mortality rates were 19.2% and 0.3%, respectively. The most common complications were wound infection at 4.8% followed by anastomotic leak and pulmonary complications at 4.5% each. Following PTG, 88.6% of patients had early lesions amongst 414 patients. The mean/median number of signet ring cell carcinoma foci in the gastrectomy specimens was from 2 to 78. All cases were stage 1 with no lymph node involvement. There was a wide range of psychosocial effects following PTG closely related to the physical symptoms. It is imperative for patients to receive comprehensive preoperative counselling to make an informed decision and be followed up under the care of a multidisciplinary team.

Unique challenges of risk-reducing surgery for hereditary diffuse gastric cancer syndrome: a narrative review

The common use of genetic testing has reinvigorated discussions surrounding enhanced cancer surveillance, chemoprevention, and preventive surgery strategies due to increasing recognition of pathogenic germline genetic variants. Prophylactic surgery for hereditary cancer syndromes can significantly reduce the risk of developing cancer. Hereditary diffuse gastric cancer (HDGC), characterized by high penetrance and an autosomal dominant inheritance pattern, is causally linked to germline mutations in the CDH1 tumor suppressor gene. Risk-reducing total gastrectomy is currently recommended in patients with pathogenic and likely pathogenic CDH1 variants; however, the physical and psychosocial sequelae of complete stomach removal are substantial and need to be investigated further. In this review, we address the risks and benefits of prophylactic total gastrectomy for HDGC in the context of prophylactic surgery for other highly penetrant cancer syndromes.

Confocal endomicroscopy diagnostic criteria for early signet-ring cell carcinoma in hereditary diffuse gastric cancer

BACKGROUND

Recognition of early signet-ring cell carcinoma (SRCC) in patients with hereditary diffuse gastric cancer (HDGC) undergoing endoscopic surveillance is challenging. We hypothesized that probe-based confocal laser endomicroscopy (pCLE) might help diagnose early cancerous lesions in the context of HDGC. The aim of this study was to identify pCLE diagnostic criteria for early SRCC.

METHODS

Patients with HDGC syndrome were prospectively recruited and pCLE assessment was performed on areas suspicious for early SRCC and control regions during an endoscopic surveillance procedure. Targeted biopsies were taken for gold standard histologic assessment. In Phase I two investigators assessed video sequences off-line to identify pCLE features related to SRCC. In Phase II pCLE diagnostic criteria were evaluated in an independent video set by the investigators blinded to the histologic diagnosis. Sensitivity, specificity, accuracy, and interobserver agreement were calculated.

RESULTS

Forty-two video sequences from 16 HDGC patients were included in Phase I. Four pCLE patterns associated to SRCC histologic features were identified: (A) glands with attenuated margins, (B) glands with spiculated or irregular shape, (C) heterogenous granular stroma with sparse glands, (D) enlarged vessels with tortuous shape. In Phase II, 38 video sequences from 15 patients were assessed. Criteria A and B and C had the highest diagnostic accuracy, with a κ for interobserver agreement ranging from 0.153 to 0.565. A panel comprising these 3 criteria with a cut-off of at least one positive criterion had a sensitivity of 80.9% (95%CI:58.1-94.5%) and a specificity of 70.6% (95%CI:44.0-89.7%) for a diagnosis of SRCC.

CONCLUSIONS

We have generated and validated off-line pCLE criteria for early SRCC. Future real-time validation of these criteria is required.

Hereditary Diffuse Gastric Cancer

Hereditary diffuse gastric cancer (HDGC) is a dominantly inherited cancer syndrome characterized by a high incidence of diffuse gastric cancer (DGC) and lobular breast cancer (LBC). HDGC is caused by germline mutations in 2 genes involved in the epithelial adherens junction complex, CDH1 and CTNNA1. We discuss the genetics of HDGC and the variability of its clinical phenotype, in particular the variable penetrance of advanced DGC and LBC, both within and between families. We review the pathology of the disease, the mechanism of tumor initiation, and its natural history. Finally, we describe current best practice for the clinical management of HDGC, including emerging genetic testing criteria for the identification of new families, methods for endoscopic surveillance, the complications associated with prophylactic surgery, postoperative quality of life, and the emerging field of HDGC chemoprevention.

Becoming and being a parent with an inherited predisposition to diffuse gastric cancer: A qualitative study of young adults with a CDH1 pathogenic variant

PURPOSE

This study explored the experiences of young people with hereditary diffuse gastric cancer (HDGC), an inherited cancer predisposition syndrome, as they navigate becoming and being a parent.

DESIGN

We used interpretive description and conducted semi-structured interviews with 13 young Australians (18-39 years) with a CDH1 pathogenic variant (PV). Data were analyzed using team-based, reflexive thematic analysis.

FINDINGS

Participants' reproductive decisions centered on the perceived manageability of HDGC, namely via gastrectomy, and timing of their genetic testing. Participants yet to have children and those with challenging gastrectomy experiences favored using reproductive technologies to prevent passing on their PV. Parents who had children before genetic testing described complicated decisions about having more children. Gastrectomy was considered a parental responsibility but recovery diminished parenting abilities.

CONCLUSION

Young people with HDGC face unique challenges navigating reproductive decision-making and parenting with gastrectomy. Findings lend credence to calls for longitudinal, developmentally sensitive genetic counseling services.

Hereditary Diffuse Gastric Cancer: Molecular Genetics, Biological Mechanisms and Current Therapeutic Approaches

Hereditary diffuse gastric cancer is an autosomal dominant syndrome characterized by a high prevalence of diffuse gastric cancer and lobular breast cancer. It is caused by inactivating mutations in the tumor suppressor gene CDH1. Genetic testing technologies have become more efficient over the years, also enabling the discovery of other susceptibility genes for gastric cancer, such as CTNNA1 among the most important genes. The diagnosis of pathogenic variant carriers with an increased risk of developing gastric cancer is a selection process involving a multidisciplinary team. To achieve optimal long-term results, it requires shared decision-making in risk management. In this review, we present a synopsis of the molecular changes and current therapeutic approaches in HDGC based on the current literature.

Loss of E-Cadherin Leads to Druggable Vulnerabilities in Sphingolipid Metabolism and Vesicle Trafficking

Simple Summary

Germline loss of the CDH1 gene is the primary genetic basis for hereditary diffuse gastric cancer, a disease resulting in elevated risk of both diffuse gastric cancer and lobular breast cancer. Current preventative treatment consists of prophylactic total gastrectomy, a therapy with several associated long-term morbidities. To address the lack of targeted molecular therapies for hereditary diffuse gastric cancer, we have utilized a synthetic lethal approach to identify candidate compounds that can specifically kill CDH1-null cells. Inhibitors of sphingolipid metabolism and vesicle trafficking pathways were identified as promising candidate compounds in a cell line model of CDH1 loss, then further validated in murine-derived organoid models of hereditary diffuse gastric cancer. With further research, these findings may lead to the development of novel chemoprevention strategies for the treatment of hereditary diffuse gastric cancer.

Abstract

Germline inactivating variants of CDH1 are causative of hereditary diffuse gastric cancer (HDGC), a cancer syndrome characterized by an increased risk of both diffuse gastric cancer and lobular breast cancer. Because loss of function mutations are difficult to target therapeutically, we have taken a synthetic lethal approach to identify targetable vulnerabilities in CDH1-null cells. We have previously observed that CDH1-null MCF10A cells exhibit a reduced rate of endocytosis relative to wildtype MCF10A cells. To determine whether this deficiency is associated with wider vulnerabilities in vesicle trafficking, we screened isogenic MCF10A cell lines with known inhibitors of autophagy, endocytosis, and sphingolipid metabolism. Relative to wildtype MCF10A cells, CDH1^−/− MCF10A cells showed significantly greater sensitivity to several drugs targeting these processes, including the autophagy inhibitor chloroquine, the endocytosis inhibitors chlorpromazine and PP1, and the sphingosine kinase 1 inhibitor PF-543. Synthetic lethality was confirmed in both gastric and mammary organoid models of CDH1 loss, derived from CD44-Cre/Cdh1^fl/fl/tdTomato mice. Collectively, these results suggest that both sphingolipid metabolism and vesicle trafficking represent previously unrecognised druggable vulnerabilities in CDH1-null cells and may lead to the development of new therapies for HDGC.

Young people's experiences of a CDH1 pathogenic variant: Decision-making about gastric cancer risk management

The most effective option for gastric cancer risk management in individuals with a CDH1 germline pathogenic or likely pathogenic variant (PV) in Australia is prophylactic total gastrectomy (PTG). There is, however, increasing confidence in endoscopic surveillance as a risk management strategy thus affording individuals with a CDH1 PV with challenging decisions regarding their gastric cancer risk management. For young people, this decision-making comes at a complex development stage of emerging and young adulthood. This study aims to explore the factors that influence young people's decision-making about their gastric cancer risk management due to a CDH1 PV. Potential participants were identified and approached through the Parkville Familial Cancer Centre in Melbourne, Australia. Thematic analysis was used to interpret and analyze the data. Qualitative interviews were conducted with 13 people with a CDH1 PV aged 18 to 39 years, inclusive. The interviews found that participants' familial and shared experiences of cancer and risk management, perceived tolerance of uncertainty, and desire for control over their cancer risk were fundamental in their decision-making about their gastric cancer risk management. The participants' young adult life stage was also deemed particularly important in decisions about the timing of PTG. The findings of this study are vital to inform decisional counseling discussions with this unique population.

CDH1 Gene Mutation Hereditary Diffuse Gastric Cancer Outcomes: Analysis of a Large Cohort, Systematic Review of Endoscopic Surveillance, and Secondary Cancer Risk Postulation

Simple Summary

Some patients carry a mutated copy of the CDH1 gene that can lead to a very rare form of hereditary gastric cancer called signet-ring cell adenocarcinoma (SRCC). SRCCs rarely form visible tumors prior to spreading. Hence, patients are recommended to have prophylactic gastrectomies at a young age. Many patients wish to avoid surgery and thus have regular checks with upper endoscopy with biopsies to rule out cancer. Further, these patients may also be at risk of other cancers beyond the already known breast cancer risks, but this is not known. In this study, we show that despite systematic biopsy protocols, many early cancers might be missed on endoscopy. Therefore, patients should not rely on endoscopy to delay surgery. These patients may also be at increased risk of colorectal SRCC, which has very poor survival outcomes. To confirm this, we need a central database that captures outcomes for this patient population.

Abstract

Hereditary diffuse gastric cancer (HDGC) is a rare signet-ring cell adenocarcinoma (SRCC) linked to CDH1 (E-cadherin) inactivating germline mutations, and increasingly other gene mutations. Female CDH1 mutation carriers have additional risk of lobular breast cancer. Risk management includes prophylactic total gastrectomy (PTG). The utility of endoscopic surveillance is unclear, as early disease lacks macroscopic lesions. The current systematic biopsy protocols have unknown efficacy, and other secondary cancer risks are postulated. We conducted a retrospective study of consecutive asymptomatic HDGC patients undergoing PTG, detailing endoscopic, pathologic, and outcome results. A systematic review compared endoscopic biopsy foci detection via random sampling versus Cambridge Protocol against PTG findings. A population-level secondary-cancer-risk postulation among sporadic gastric SRCC patients was completed using the Surveillance, Epidemiology, and End Results database. Of 97 patients, 67 underwent PTG, with 25% having foci detection on random endoscopic biopsy despite 75% having foci on final pathology. There was no improvement in the endoscopic detection rate by Cambridge Protocol. The postulated hazard ratio among sporadic gastric SRCC patients for a secondary colorectal SRCC was three-fold higher, relative to conventional adenocarcinoma patients. Overall, HDGC patients should not rely on endoscopic surveillance to delay PTG, and may have secondary SRCC risks. A definitive determination of actual risk requires collaborative patient outcome data banking.

Hereditary Diffuse Gastric Cancer: Approaches to Screening, Surveillance, and Treatment

Hereditary diffuse gastric cancer (HDGC) is a cancer syndrome associated with a significant lifetime risk of diffuse gastric cancer (DGC), a malignancy characterized by late clinical presentation and poor prognosis, as well as lobular breast cancer. HDGC is linked to germline pathogenic variants in the E-cadherin gene (CDH1) that are inherited in an autosomal dominant pattern; however, in many families with DGC clustering, no genetic cause has been identified. This review discusses key elements that allow risk assessment of potential inherited DGC susceptibility. We provide a practical overview of the recommendations for surveillance and treatment of individuals at risk and patients with early disease. The review also outlines future research avenues to improve our understanding of the genetic background and natural history of the disease, the endoscopic detection of early lesions, and the outcome of prophylactic surgery in young individuals.

Gastroscopic surveillance with targeted biopsies compared with random biopsies in CDH1 mutation carriers

BACKGROUND : The International Gastric Cancer Linkage Consortium (IGCLC) consensus guideline advises prophylactic gastrectomy in early adulthood to prevent gastric cancer development in CDH1 germline mutation carriers; psychosocial reasons may postpone gastrectomy. We analyzed the yield of signet-ring cell carcinoma (SRCC) during surveillance gastroscopy in CDH1 mutation carriers. METHODS : A retrospective analysis on surveillance gastroscopies in CDH1 mutation carriers was performed. The yield of SRCC in both targeted and random biopsies was studied. Endoscopic (biopsy) results were compared with the histopathologic outcomes in gastrectomy specimens. RESULTS : 42 CDH1 mutation carriers (18 men; mean age 43, range 20-82 years) underwent 96 surveillance gastroscopies. SRCC lesions were identified on surveillance gastroscopy in 21 patients (50 %), by either targeted biopsies only (n = 11), random biopsies only (n = 3), or both random and targeted biopsies (n = 7). SRCC was detected in 41 /377 targeted biopsies (11 %), whereas random biopsies revealed SRCC in 14/1563 biopsies (0.9 %). At least one SRCC lesion was found in 26 of 30 gastrectomy specimens. In 18 of these 26 specimens (69 %), SRCC had been identified by endoscopic biopsies. Missed lesions were all small superficial SRCC foci, mainly in the body of the stomach. CONCLUSION : In our cohort of CDH1 mutation carriers, SRCC lesions were identified by an extensive endoscopic surveillance protocol in 69 % of SRCC-positive patients who underwent a gastric resection. The low number of SRCC detected through random sampling demands a critical reappraisal of random biopsy sampling in the IGCLC guideline.

Hereditary diffuse gastric cancer: updated clinical practice guidelines

Hereditary diffuse gastric cancer (HDGC) is an autosomal dominant cancer syndrome that is characterised by a high prevalence of diffuse gastric cancer and lobular breast cancer. It is largely caused by inactivating germline mutations in the tumour suppressor gene CDH1, although pathogenic variants in CTNNA1 occur in a minority of families with HDGC. In this Policy Review, we present updated clinical practice guidelines for HDGC from the International Gastric Cancer Linkage Consortium (IGCLC), which recognise the emerging evidence of variability in gastric cancer risk between families with HDGC, the growing capability of endoscopic and histological surveillance in HDGC, and increased experience of managing long-term sequelae of total gastrectomy in young patients. To redress the balance between the accessibility, cost, and acceptance of genetic testing and the increased identification of pathogenic variant carriers, the HDGC genetic testing criteria have been relaxed, mainly through less restrictive age limits. Prophylactic total gastrectomy remains the recommended option for gastric cancer risk management in pathogenic CDH1 variant carriers. However, there is increasing confidence from the IGCLC that endoscopic surveillance in expert centres can be safely offered to patients who wish to postpone surgery, or to those whose risk of developing gastric cancer is not well defined.

Barriers and facilitators to CDH1 carriers contemplating or undergoing prophylactic total gastrectomy

Hereditary diffuse gastric cancer (HDGC) is an inherited cancer syndrome associated with high lifetime risk of diffuse-type gastric cancer. Current guidelines recommend individuals with HDGC undergo prophylactic total gastrectomy (PTG) to eliminate this risk. However, PTG is associated with significant lifestyle changes, post-surgical recovery, and symptom burden. This study examined factors related to decision-making about PTG in three groups of individuals who: (1) underwent PTG immediately after receiving genetic testing results; (2) delayed PTG by ≥ 1 year or; (3) declined PTG. Participants were recruited from a familial gastric cancer registry at a tertiary care hospital. Patients with CDH1 pathogenic or likely pathogenic variants who contemplated and/or underwent PTG were eligible. 24 individuals contemplated PTG: 9 had immediate surgery (within a year), 8 delayed surgery, and 7 declined surgery. Data on PTG barriers and facilitators were obtained on all participants using quantitative surveys (n = 7), qualitative interviews (n = 8) or both methods (n = 9). PTG barriers included age, positive beliefs about screening, close relatives with negative PTG experiences, fertility-related concerns, and life stress. Facilitators included social support, trust in healthcare providers, understanding risk, negative beliefs about screening, family-related factors, positive or abnormal screening results, and positive attitude toward PTG. This study highlights factors related to the PTG decision-making process among individuals with HDGC from three distinct groups. Future research should explore educational interventions aimed at addressing surgery-related concerns and the limitations of screening, and might also consider incorporating close relatives as informational supports.

Paving the Way: A Grounded Theory of Discovery and Decision Making for Individuals With the CDH1 Marker

PURPOSE

To understand the process of discovery and decision making for adults with the CDH1 marker for hereditary diffuse gastric cancer and inherited breast cancer.

PARTICIPANTS & SETTING

Purposeful sampling included 20 participants.

METHODOLOGIC APPROACH

Grounded theory with constant comparison was used.

FINDINGS

The decision-making process of Paving the Way addresses the challenges for individuals diagnosed with the CDH1 marker. The theory explains the process of learning the risk, discerning testing, choosing iterative individual interventions, and adjusting postoperatively while normalizing to live longer.

IMPLICATIONS FOR NURSING

The process explains and describes the nine factors for decision making and predicts the timing for nursing interventions for genetic testing and pre- and postoperative assessment and planning.

Gastric Necrosis After Binge Eating in Bulimia: Recovery From Eating Disorder After Total Gastrectomy

BACKGROUND

Gastric necrosis following acute gastric dilatation is rare but more common in females with eating disorders, such as anorexia nervosa or bulimia, during which patients often alternate restriction and binge eating behaviors.

CASE PRESENTATION

A 37-year old female patient with a history of 15 years of bulimia nervosa was admitted to the emergency department 24 h after binge eating. Abdominal Computed Tomography imaging showed major gastric distension reaching the pelvis and compressing the digestive organs. Total gastrectomy was required because of gastric necrosis. The patient reported significant reduction in bulimic symptoms after gastrectomy.

CONCLUSION

We discuss here the possible mechanisms underlying this recovery, including changes in gut-derived factors that could mediate eating behavior changes.

CDH1 (E-Cadherin) Mutation and Gastric Cancer: Genetics, Molecular Mechanisms and Guidelines for Management

Introduction

Germline mutation in CDH1 (E-cadherin) tumor suppressor gene is associated with hereditary diffuse gastric cancer (HDGC) and lobular breast cancers (LBC). E-Cadherin protein is necessary for physiological signaling pathways, such as cell proliferation, maintenance of cell adhesion, cell polarity and epithelial-mesenchymal transition. Dysregulation leads to tumor proliferation, invasion, migration and metastases. We review current perspectives in CDH1 genetics with molecular mechanisms and also discuss management strategies for this aggressive form of gastric cancer.

Methods

Relevant articles from PubMed/Medline and Embase (1994–2019) were searched and collected using the phrases “Hereditary diffuse gastric cancer, Familial gastric cancer, CDH1 mutation, E-Cadherin, Lobular breast cancer, Prophylactic total gastrectomy”.

Results

Current guidelines suggest maintaining a high degree of suspicion of hereditary etiology and recommend testing for CDH1 mutations in patients with familial clustering of HDGC and LBC, especially onset at an early age (before 40 years). In families lacking CDH1 mutations but with high suspicion for hereditary predisposition, testing of CTNNA1 and other closely related HDGC susceptibility genes could be considered. Prophylactic total gastrectomy is recommended for individuals with identified pathogenic germline variants. Endoscopic surveillance with biopsies is recommended for those choosing to delay prophylactic gastrectomy.

Conclusion

Mutation or transcriptional silencing of the CDH1 gene is associated with familial diffuse gastric cancer. Further studies on the expression and the alteration in the proteins in the E-cadherin pathways may serve as biomarkers for early detection; stratify risk and selection of appropriate therapy in these families. Until then prophylactic total gastrectomy is recommended for individuals with CDH1 mutations and family history of diffuse gastric cancer. Endoscopic surveillance and biopsies by experienced gastroenterologists is recommended for those choosing not to have prophylactic gastrectomy and in individuals with CDH1 variants.

The role of endoscopy in the management of hereditary diffuse gastric cancer syndrome

Hereditary diffuse gastric cancer (HDGC) syndrome is an inherited cancer risk syndrome associated with pathogenic germline CDH1 variants. Given the high risk for developing diffuse gastric cancer, CDH1 carriers are recommended to undergo prophylactic total gastrectomy for cancer risk reduction. Current guidelines recommend upper endoscopy in CDH1 carriers prior to surgery and then annually for individuals deferring prophylactic total gastrectomy. Management of individuals from HDGC families without CDH1 pathogenic variants remains less clear, and management of families with CDH1 pathogenic variants in the absence of a family history of gastric cancer is particularly problematic at present. Despite adherence to surveillance protocols, endoscopic detection of cancer foci in HDGC is suboptimal and imperfect for facilitating decision-making. Alternative endoscopic modalities, such as chromoendoscopy, endoscopic ultrasound, and other non-white light methods have been utilized, but are of limited utility to further improve cancer detection and risk stratification in HDGC. Herein, we review what is known and what remains unclear about endoscopic surveillance for HDGC, among individuals with and without germline CDH1 pathogenic variants. Ultimately, the use of endoscopy in the management of HDGC remains a challenging arena, but one in which further research to improve surveillance is crucial.

Patients' Medical and Psychosocial Experiences After Detection of a CDH1 Variant With Multigene Panel Testing

PURPOSE

Germline CDH1 pathogenic variants (PV) are associated with hereditary diffuse gastric cancer and lobular breast cancer. Although prevalence of CDH1 PV is low in the general population, detection of these variants is increasing with the growing use of multigene panel testing. Little is known about the experiences of individuals tested for CDH1 variants in the multigene panel testing era.

METHODS

Participants recruited from the Prospective Registry of Multiplex Testing completed a cross-sectional self-report survey regarding CDH1 genetic testing experiences, medical management, and psychosocial adaptation.

RESULTS

Discordance existed in interpretations of CDH1 results; 13.3% of cases had disagreements in variant classifications among commercial laboratories, and 21.4% had disagreements between participant self-report and ClinVar classification. Survey data were available from 57 individuals reporting either PV (n = 16) or variants of uncertain significance (VUS; n = 41). Those with PV were more likely than those with VUS to report receiving a recommendation for prophylactic gastrectomy, although only 40.0% of those with PV received this recommendation. Participants with VUS were less satisfied with their health care providers' knowledge and reported less CDH1 knowledge, distress, and worry about discrimination. Participants with PV perceived greater breast cancer risks, but similar gastric cancer risks, as those with VUS.

CONCLUSION

Few individuals with CDH1 PV report receiving recommendations for prophylactic gastrectomy, and no differences in perceived gastric cancer risk were observed based on participants' CDH1 results, suggesting serious unmet informational needs.

Outcomes after prophylactic gastrectomy for hereditary diffuse gastric cancer

BACKGROUND

Patients with hereditary diffuse gastric cancer and a CDH1 mutation have a 60-80 per cent lifetime risk of developing diffuse gastric cancer. Total prophylactic gastrectomy eliminates this risk, but is associated with considerable morbidity. The effectiveness (removal of all gastric mucosa) and outcomes of this procedure were evaluated retrospectively.

METHODS

All consecutive individuals undergoing a prophylactic gastrectomy for a CDH1 mutation or gastric signet ring cell foci at the authors' institute between 2005 and 2017 were included.

RESULTS

In 25 of 26 patients, intraoperative frozen-section examination (proximal resection margin) was used to verify complete removal of gastric mucosa. All definitive resection margins were free of gastric mucosa, but only after the proximal margin had been reresected in nine patients. In the first year after surgery, five of the 26 patients underwent a relaparotomy for adhesiolysis (2 patients) or jejunostomy-related complications (3 patients). Six patients were readmitted to the hospital within 1 year for nutritional and/or psychosocial support (4 patients) or surgical reintervention (2 patients). Mean weight loss after 1 year was 15 (95 per cent c.i. 12 to 18) per cent. For the 25 patients with a follow-up at 1 year or more, functional complaints were reported more frequently at 1 year than at 3 months after the operation: bile reflux (15 versus 11 patients respectively) and dumping (11 versus 7 patients). The majority of patients who worked or studied before surgery (15 of 19) had returned fully to these activities within 1 year.

CONCLUSION

The considerable morbidity and functional consequences of gastrectomy should be considered when counselling individuals with an inherited predisposition to diffuse gastric cancer. Intraoperative frozen-section examination is recommended to remove all risk-bearing gastric mucosa.

Pathological features of total gastrectomy specimens from asymptomatic hereditary diffuse gastric cancer patients and implications for clinical management

Hereditary diffuse gastric cancer (HDGC) is an autosomal dominant syndrome characterised by multigenerational diffuse gastric cancer, and is mainly caused by germline alterations in the CDH1 gene. Currently, endoscopy has limited diagnostic accuracy, and total gastrectomy (TG) is the treatment of choice for asymptomatic CDH1 carriers. In this study, we aimed to obtain a better understanding of HDGC syndrome by exploring the histopathological findings of TG specimens from asymptomatic HDGC patients. A comprehensive literature review was carried out, searching for TGs performed in asymptomatic HDGC patients. Fourteen unpublished cases, analysed in our institution, were also included. The series encompassed 174 CDH1 carriers. Preoperative endoscopic biopsies were positive in 28.3%. A macroscopic lesion was apparent in 11.7% of TGs. Histopathological analysis revealed intraepithelial lesions and/or intramucosal signet ring cell carcinoma in 87.9% of TGs. When we explored the type of protocol used for handling the specimens, we found that microscopic cancer foci were detected in 95.3% of TGs when a total-embedding protocol (assessment of the totality of gastric mucosa) was applied, and only in 62.5% when no specific protocol was used (P < 0.001). Helicobacter pylori infection was found in 23.4% cases. In conclusion, a thorough histopathological examination of gastric mucosa remains the gold standard for detection of cancer foci in HDGC gastrectomy specimens, requiring experienced pathologists for an accurate diagnosis. A better understanding of the natural history of HDGC will enable better clinical management of HDGC patients, particularly regarding the optimal timing for the performance of TG.

Quality-of-life implications of risk-reducing cancer surgery

Background

Modern advances in genetic sequencing techniques have allowed for increased availability of genetic testing for hereditary cancer syndromes. Consequently, more people are being identified as mutation carriers and becoming aware of their increased risk of malignancy. Testing is commonplace for many inheritable cancer syndromes, and with that comes the knowledge of being a gene carrier for some patients. With increased risk of malignancy, many guidelines recommend that gene carriers partake in risk reduction strategies, including risk-reducing surgery for some syndromes. This review explores the quality-of-life consequences of genetic testing and risk-reducing surgery.

Methods

A narrative review of PubMed/MEDLINE was performed, focusing on the health-related quality-of-life implications of surgery for hereditary breast and ovarian cancer, familial adenomatous polyposis and hereditary diffuse gastric cancer.

Results

Risk-reducing surgery almost uniformly decreases cancer anxiety and affects patients' quality of life.

Conclusion

Although the overwhelming quality-of-life implications of surgery are neutral to positive, risk-reducing surgery is irreversible and can be associated with short- and long-term side-effects.