Impact of genetic testing on endometrial cancer risk-reducing practices in women at risk for Lynch syndrome

Risk-reducing surgery in unaffected individuals receiving cancer genetic testing in an integrated health care system

BACKGROUND

Germline genetic testing enables primary cancer prevention, including through prophylactic surgery. We examined risk-reducing surgeries in unaffected individuals tested for hereditary cancer susceptibly between 2010 and 2018 in the Kaiser Permanente Northwest health system.

METHODS

We used an internal genetic testing database to create a cohort of individuals who received tests including one or more high-penetrance hereditary cancer susceptibility gene. We then identified, after testing, bilateral mastectomy, bilateral salpingo-oophorectomy (BSO), and total hysterectomy procedures in electronic health record and claims data through 2019. We describe surgery utilization by genetic test results and National Comprehensive Cancer Network (NCCN) guidelines.

RESULTS

The cohort included 1020 individuals, 16% with pathogenic/likely pathogenic (P/LP) variants in one or more of the following genes: BRCA1, BRCA2, CHEK2, APC, MUTYH, ATM, MSH2, PALB2, BRIP1, MLH1, MSH6, EPCAM, FLCN, RAD51C, RAD51D, or TP53. Among individuals with P/LP variants making them candidates for mastectomy, BSO, or hysterectomy per NCCN guidelines, 34% (33/97), 24% (23/94), and 8% (1/12), respectively, underwent surgery during follow-up. Fifty-three percent (18/37) of hysterectomies were among APC, BRCA1, and BRCA2 P/LP variant heterozygotes, typically concurrent with BSO. Three individuals with variants of uncertain significance (only) and 22 with negative results had prophylactic surgery after genetic testing.

CONCLUSIONS

Uptake of risk-reducing surgery following usual care genetic testing appears to be lower than in studies that actively recruit high-risk patients and provide testing and follow-up care in specialized settings. Factors in addition to genetic test results and NCCN guidelines motivate prophylactic surgery use and deserve further study.

Evaluation of implementation of risk management guidelines for carriers of pathogenic variants in mismatch repair genes: a nationwide audit of familial cancer clinics

INTRODUCTION

This nationwide study assessed the impact of Lynch syndrome-related risk management guidelines on clinicians' recommendations of risk management strategies to carriers of pathogenic variants in mismatch repair genes and the extent to which carriers took up strategies in concordance with guidelines.

MATERIALS AND METHODS

Clinic files of 464 carriers (with and without colorectal cancer) were audited for carriers who received their genetic testing results in July 2008-July 2009 (i.e. before guideline release), July 2010-July 2011 and July 2012-July 2013 (both after guideline release) at 12 familial cancer clinics (FCCs) to ascertain the extent to which carriers were informed about risk management in accordance with guidelines. All carriers captured by the audit were invited to participate in interviews; 215 were interviewed to assess adherence to recommended risk management guidelines.

RESULTS

The rates of documentation in clinic files increased significantly from pre- to post-guideline for only two out of eight risk management strategies. The strategies with the highest compliance of carriers post-guidelines were: uptake of one or two-yearly colonoscopy (87%), followed by hysterectomy to prevent endometrial cancer (68%), aspirin as risk-reducing medication (67%) and risk-reducing salpingo-oophorectomy (63%). Interrater reliability check for all guidelines showed excellent agreement (k statistics = 0.89).

CONCLUSION

These results indicate that there is scope to further increase provision of advice at FCCs to ensure that all carriers receive recommendations about evidence-based risk management. A multi-pronged behaviour change and implementation science approach tailored to specific barriers is likely to be needed to achieve optimal clinician behaviours and outcomes for carriers.

Prophylactic Risk-reducing Hysterectomies and Bilateral Salpingo-oophorectomies in Patients With Lynch Syndrome: A Clinicopathologic Study of 29 Cases and Review of the Literature

Lynch syndrome (LS) is associated with an increased risk for colorectal, endometrial, and ovarian carcinomas in women. Risk-reducing hysterectomy and bilateral salpingo-oophorectomy (RRHSO) has been shown to be a cost-effective form of management and prevention of gynecological malignancies in patients with LS. Studies of incidental gynecologic malignancies identified in RRHSO are limited. In addition, recommendations on optimal handling of this type of specimen have ranged from submitting for microscopic examination the entire endometrium, fallopian tubes and ovaries to submitting only routine representative sections of these organs. In this study, we present the clinicopathologic findings of 29 cases of LS patients that underwent risk-reducing gynecologic surgery at our institution over a period of 13 yr. Clinical-pathologic information was obtained from the patients' charts and pathology reports. Significant pathologic abnormalities were identified in 17% (5/29) of cases, all showing endometrial hyperplasia. Four of them with atypical and 1 without atypical. All of our cases with endometrial pathology had significant findings on preoperative endometrial sampling. To further study the recommendation of in toto submission of the endometrium, ovaries and fallopian tubes and the utility of preoperative endometrial sampling, we undertook a literature review of all the reported cases of incidental pathologic findings identified in RRHSO. The findings of our cohort and the literature reviewed support in toto submission of endometrium, and adnexal structures in the absence of gross lesions. In addition, our findings show a definite benefit for preoperative endometrial sampling as part of the workup for LS patients undergoing RRHSO.

Recommended care and care adherence following a diagnosis of Lynch syndrome: a mixed-methods study

BACKGROUND

Lynch syndrome (LS) is the most common hereditary colorectal cancer (CRC) syndrome. This study assesses trends in diagnosis of LS and adherence to recommended LS-related care in a large integrated healthcare organization (~ 575,000 members).

METHODS

Electronic medical record (EMR) data (1999-2015) were examined to identify patients with a diagnosis of LS. We examined their LS-associated care recommendations and adherence to these recommendations. Qualitative patient and provider interviews were conducted with the aim of identifying opportunities for improved care delivery.

RESULTS

We identified 74 patients with a diagnosis of LS; 64% were diagnosed with a LS-related malignancy prior to their diagnosis of LS. The time to LS diagnosis following development of a LS-related cancer decreased over time: before 2009 11% of individuals received a diagnosis of LS within 1 year of developing a LS-related cancer compared to 83% after 2009 (p < 0.0001). Colonoscopy recommendations were documented in the EMR for almost all patients with LS (96%). Documentation of other recommendations for cancer surveillance was less commonly found. Overall, patient adherence to colonoscopy was high (M = 81.5%; SD = 32.7%), and adherence to other recommendations varied. To improve care coordination, patients and providers suggested providing automated reminder prompts for LS-related surveillance, adding a LS-specific diagnosis code, and providing guidelines for LS-related surveillance in the EMR.

CONCLUSIONS

We identified fewer than expected patients with LS in our large care system, indicating that there is still a diagnostic care gap. However, patients with LS were likely to receive and follow CRC surveillance recommendations. Recommendations for and adherence to extracolonic surveillance were variable. Improved care coordination and clearer documentation of the LS diagnosis is needed.

Decreasing Trends of Secondary Primary Colorectal Cancer among Women with Uterine Cancer: A Population-Based Analysis

The current study examined trends, characteristics, and outcomes of women with uterine cancer who had secondary colorectal cancer. This is a retrospective study utilizing the Surveillance, Epidemiology, and End Results Program between 1973-2013. Among uterine cancer (n = 246,272) and colorectal cancer (n = 421,312) cohorts, women with both diagnoses were identified, and clinico-pathological factors and survival were extracted and analyzed. There were 6862 women with both cancer diagnoses, representing 2.8% of the uterine cancer cohort and 1.6% of the colorectal cancer cohort. Among 123,940 women with uterine cancer survivors, the number with postcedent colorectal cancer decreased from 5.3% to 0.7% between 1981-2008 (relative risk reduction 87.0% p < 0.001). Similarly, of 141,801 women with colorectal cancer survivors, the number with postcedent uterine cancer decreased from 1.7% to 0.5% between 1973-2008 (relative risk reduction 71.6%, p < 0.001). In the uterine cancer cohort, women with antecedent/synchronous colorectal cancer had more high-grade tumors and advanced-stage disease resulting in poorer survival, whereas those who had postcedent colorectal cancer had more low-grade tumors and early-stage disease resulting in superior survival compared to those without secondary colorectal cancer (all, p < 0.05). In conclusion, the development of postcedent colorectal cancer following uterine cancer has decreased in recent years in the United States.

Endometrial Carcinoma, Grossing and Processing Issues: Recommendations of the International Society of Gynecologic Pathologists

Endometrial cancer is the most common gynecologic neoplasm in developed countries; however, updated universal guidelines are currently not available to handle specimens obtained during the surgical treatment of patients affected by this disease. This article presents recommendations on how to gross and submit sections for microscopic examination of hysterectomy specimens and other tissues removed during the surgical management of endometrial cancer such as salpingo-oophorectomy, omentectomy, and lymph node dissection—including sentinel lymph nodes. In addition, the intraoperative assessment of some of these specimens is addressed. These recommendations are based on a review of the literature, grossing manuals from various institutions, and a collaborative effort by a subgroup of the Endometrial Cancer Task Force of the International Society of Gynecological Pathologists. The aim of these recommendations is to standardize the processing of endometrial cancer specimens which is vital for adequate pathological reporting and will ultimately improve our understanding of this disease.

Multicenter Prospective Cohort Study of the Diagnostic Yield and Patient Experience of Multiplex Gene Panel Testing For Hereditary Cancer Risk

Purpose

Multiplex gene panel testing (MGPT) allows for the simultaneous analysis of germline cancer susceptibility genes. This study describes the diagnostic yield and patient experiences of MGPT in diverse populations.

Patients and Methods

This multicenter, prospective cohort study enrolled participants from three cancer genetics clinics—University of Southern California Norris Comprehensive Cancer Center, Los Angeles County and University of Southern California Medical Center, and Stanford Cancer Institute—who met testing guidelines or had a 2.5% or greater probability of a pathogenic variant (N = 2,000). All patients underwent 25- or 28-gene MGPT and results were compared with differential genetic diagnoses generated by pretest expert clinical assessment. Post-test surveys on distress, uncertainty, and positive experiences were administered at 3 months (69% response rate) and 1 year (57% response rate).

Results

Of 2,000 participants, 81% were female, 41% were Hispanic, 26% were Spanish speaking only, and 30% completed high school or less education. A total of 242 participants (12%) carried one or more pathogenic variant (positive), 689 (34%) carried one or more variant of uncertain significance (VUS), and 1,069 (53%) carried no pathogenic variants or VUS (negative). More than one third of pathogenic variants (34%) were not included in the differential diagnosis. After testing, few patients (4%) had prophylactic surgery, most (92%) never regretted testing, and most (80%) wanted to know all results, even those of uncertain significance. Positive patients were twice as likely as negative/VUS patients (83% v 41%; P < .001) to encourage their relatives to be tested.

Conclusion

In a racially/ethnically and socioeconomically diverse cohort, MGPT increased diagnostic yield. More than one third of identified pathogenic variants were not clinically anticipated. Patient regret and prophylactic surgery use were low, and patients appropriately encouraged relatives to be tested for clinically relevant results.

A Systematic Review on the Existing Screening Pathways for Lynch Syndrome Identification

Background

Lynch syndrome (LS) is the most common hereditary colon cancer syndrome, accounting for 3–5% of colorectal cancer (CRC) cases, and it is associated with the development of other cancers. Early detection of individuals with LS is relevant, since they can take advantage of life-saving intensive care surveillance. The debate regarding the best screening policy, however, is far from being concluded. This prompted us to conduct a systematic review of the existing screening pathways for LS.

Methods

We performed a systematic search of MEDLINE, ISI Web of Science, and SCOPUS online databases for the existing screening pathways for LS. The eligibility criteria for inclusion in this review required that the studies evaluated a structured and permanent screening pathway for the identification of LS carriers. The effectiveness of the pathways was analyzed in terms of LS detection rate.

Results

We identified five eligible studies. All the LS screening pathways started from CRC cases, of which three followed a universal screening approach. Concerning the laboratory procedures, the pathways used immunohistochemistry and/or microsatellite instability testing. If the responses of the tests indicated a risk for LS, the genetic counseling, performed by a geneticist or a genetic counselor, was mandatory to undergo DNA genetic testing. The overall LS detection rate ranged from 0 to 5.2%.

Conclusion

This systematic review reported different existing pathways for the identification of LS patients. Although current clinical guidelines suggest to test all the CRC cases to identify LS cases, the actual implementation of pathways for LS identification has not been realized. Large-scale screening programs for LS have the potential to reduce morbidity and mortality for CRC, but coordinated efforts in educating all key stakeholders and addressing public needs are still required.

Spectrum of mismatch repair gene mutations and clinical presentation of Hispanic individuals with Lynch syndrome

Lynch syndrome (LS), the most common hereditary colorectal cancer syndrome, is caused by mismatch repair (MMR) gene mutations. However, data about MMR mutations in Hispanics are limited. This study aims to describe the spectrum of MMR mutations in Hispanics with LS and explore ancestral origins. This case series involved an IRB-approved retrospective chart review of self-identified Hispanic patients (n = 397) seen for genetic cancer risk assessment at four collaborating academic institutions in California, Texas, and Puerto Rico who were evaluated by MMR genotyping and/or tumor analysis. A literature review was conducted for all mutations identified. Of those who underwent clinical genetic testing (n = 176), 71 had MMR gene mutations. Nine mutations were observed more than once. One third (3/9) of recurrent mutations and two additional mutations (seen only once) were previously reported in Spain, confirming the influence of Spanish ancestry on MMR mutations in Hispanic populations. The recurrent mutations identified (n = 9) included both previously reported mutations as well as unique mutations not in the literature. This is the largest report of Hispanic MMR mutations in North America; however, a larger sample and haplotype analyses are needed to better understand recurrent MMR mutations in Hispanic populations.

How does genetic risk information for Lynch syndrome translate to risk management behaviours?

Background

There is limited research on why some individuals who have undergone predictive genetic testing for Lynch syndrome do not adhere to screening recommendations. This study aimed to explore qualitatively how Lynch syndrome non-carriers and carriers translate genetic risk information and advice to decisions about risk managment behaviours in the Australian healthcare system.

Methods

Participants of the Australasian Colorectal Cancer Family Registry who had undergone predictive genetic testing for Lynch syndrome were interviewed on their risk management behaviours. Transcripts were analysed thematically using a comparative coding analysis.

Results

Thirty-three people were interviewed. Of the non-carriers (n = 16), 2 reported having apparently unnecessary colonoscopies, and 6 were unsure about what population-based colorectal cancer screening entails. Of the carriers (n = 17), 2 reported they had not had regular colonoscopies, and spoke about their discomfort with the screening process and a lack of faith in the procedure’s ability to reduce their risk of developing colorectal cancer. Of the female carriers (n = 9), 2 could not recall being informed about the associated risk of gynaecological cancers.

Conclusion

Non-carriers and female carriers of Lynch syndrome could benefit from further clarity and advice about appropriate risk management options. For those carriers who did not adhere to colonoscopy screening, a lack of faith in both genetic test results and screening were evident. It is essential that consistent advice is offered to both carriers and non-carriers of Lynch syndrome.

When is Genomic Testing Cost-Effective? Testing for Lynch Syndrome in Patients with Newly-Diagnosed Colorectal Cancer and Their Relatives

Varying estimates of the cost-effectiveness of genomic testing applications can reflect differences in study questions, settings, methods and assumptions. This review compares recently published cost-effectiveness analyses of testing strategies for Lynch Syndrome (LS) in tumors from patients newly diagnosed with colorectal cancer (CRC) for either all adult patients or patients up to age 70 along with cascade testing of relatives of probands. Seven studies published from 2010 through 2015 were identified and summarized. Five studies analyzed the universal offer of testing to adult patients with CRC and two others analyzed testing patients up to age 70; all except one reported incremental cost-effectiveness ratios (ICERs) < $ 100,000 per life-year or quality-adjusted life-year gained. Three studies found lower ICERs for selective testing strategies using family history-based predictive models compared with universal testing. However, those calculations were based on estimates of sensitivity of predictive models derived from research studies, and it is unclear how sensitive such models are in routine clinical practice. Key model parameters that are influential in ICER estimates included 1) the number of first-degree relatives tested per proband identified with LS and 2) the cost of gene sequencing. Others include the frequency of intensive colonoscopic surveillance, the cost of colonoscopy, and the inclusion of extracolonic surveillance and prevention options.

Decisions about prophylactic gynecologic surgery: a qualitative study of the experience of female Lynch syndrome mutation carriers

Background

Women who carry a mutation for Lynch syndrome face complex decisions regarding strategies for managing their increased cancer risks. At present, there is limited understanding of the factors influencing women’s prophylactic surgery decisions.

Methods

As part of an exploratory pilot project, semi-structured interviews were conducted with 10 women who were Lynch syndrome mutation carriers and had made prophylactic surgery decisions. Nine of 10 women had chosen to undergo prophylactic hysterectomy and/or oophorectomy as a means of managing their increased gynecological cancer risks.

Results

Study findings revealed that surgery decisions were influenced by multiple factors, including demographic variables such as age and parity, as well as psychosocial factors such as cancer worry, in addition to personal and social knowledge of gynecological cancer. While all women were satisfied with their surgery decision, some reported they were not fully informed about the negative impact on their quality of life post-surgery (e.g., complications of surgically-induced menopause), nor about the potential for, or risks and benefits of, hormone replacement therapy.

Conclusions

Study findings highlight some of the factors associated with prophylactic surgery decisions and women’s perceptions about pre-surgical information provision and needs. Suggestions are made for improving the information and support provided to female carriers of a Lynch syndrome mutation.

Risk-reducing surgery in hereditary gynecological cancer: Clinical applications in Lynch syndrome and hereditary breast and ovarian cancer

Risk-reducing surgery (RRS) is defined as a prophylactic approach with removal of organs at high risk of developing cancer, which is performed in cases without lesions or absence of clinically significant lesions. Hereditary gynecological cancers for which RRS is performed include hereditary breast and ovarian cancer (HBOC) and Lynch syndrome. For HBOC, RRS in the United States (US) is recommended for women with mutations in the breast cancer susceptibility (BRCA)1 and BRCA2 genes and bilateral salpingo-oophorectomy (BSO) is generally performed. This procedure may reduce the risk of breast, ovarian, Fallopian tube and primary peritoneal cancer, although ovarian deficiency symptoms occur postoperatively. For Lynch syndrome, RRS in the US is considered for postmenopausal women or for women who do not desire to bear children and BSO and hysterectomy are usually performed. This approach may reduce the risk of endometrial and ovarian cancer, although ovarian deficiency symptoms also occur. For RRS, there are several issues that must be addressed to reduce the risk of cancer development in patients with HBOC or Lynch syndrome. To the best of our knowledge, this is the first review to discuss RRS with a focus on hereditary gynecological cancer.

The genetic basis of Lynch syndrome and its implications for clinical practice and risk management

Lynch syndrome is the most common cause of hereditary colon cancer, and accounts for as much as 3% of all colon and endometrial cancers. The identification and management of individuals with Lynch syndrome have evolved over the past 20 years, yet the syndrome remains vastly underdiagnosed. It is important for clinicians to recognize individuals and families who are at risk in order to be able to manage them appropriately and reduce their morbidity and mortality from this condition. This review will touch on the history of Lynch syndrome, the current knowledge of genotype–phenotype correlations, the cancers associated with Lynch syndrome, and management of individuals who are gene carriers.

One case of endometrial cancer occurrence: Over 10 years after colon cancer in Lynch family

We have recently experienced an endometrial cancer 12 years after the diagnosis of colon cancer with Lynch syndrome. A 49-year-old Korean woman had a family history of colon cancer. Her mother had colon cancer at 56-year-old, and her brother had colon cancer at 48 years old. The patient received surgery for endometrial cancer at the same hospital 12 years after being treated for colon cancer. Immunohistochemistry showed that her endometrial tissue stained negative for MSH2. A microsatellite instability test was performed and showed the presence of instability high microsatellite instability. An hMLH2 gene mutation was detected at codon 629 codon of exon 12, in which a glutamine was replaced with an arginine (1886A>G [p.Gln629Arg]). To our knowledge, this is the first case of metachronous cancer in a Lynch syndrome family in Korea with a gap of more than ten years between cancer diagnoses.

Genetic testing strategies in newly diagnosed endometrial cancer patients aimed at reducing morbidity or mortality from lynch syndrome in the index case or her relatives

Endometrial cancer is the first malignancy in 50% of women with Lynch syndrome, an autosomal dominant cancer-prone syndrome caused by germline mutations in genes encoding components of the DNA mismatch repair (MMR) pathway. These women (2-4% of all those with endometrial cancer) are at risk of metachronous colorectal cancer and other Lynch syndrome-associated cancers, and their first-degree relatives are at 50% risk of Lynch syndrome. Testing all women newly diagnosed with endometrial cancer for Lynch syndrome may have clinical utility for the index case and her relatives by alerting them to the benefits of surveillance and preventive options, primarily for colorectal cancer. The strategy involves offering germline DNA mutation testing to those whose tumour shows loss-of-function of MMR protein(s) when analysed for microsatellite instability (MSI) and/or by immunohistochemisty (IHC). In endometrial tumours from unselected patients, MSI and IHC have a sensitivity of 80-100% and specificity of 60-80% for detecting a mutation in an MMR gene, though the number of suitable studies for determining clinical validity is small. The clinical validity of strategies to exclude those with false-positive tumour test results due to somatic hypermethylation of the MLH1 gene promoter has not been determined. Options include direct methylation testing, and excluding those over the age of 60 who have no concerning family history or clinical features. The clinical utility of Lynch syndrome testing for the index case depends on her age and the MMR gene mutated: the net benefit is lower for those diagnosed at older ages and with less-penetrant MSH6 mutations. To date, women with these features are the majority of those diagnosed through screening unselected endometrial cancer patients but the number of studies is small. Similarly, clinical utility to relatives of the index case is higher if the family's mutation is in MLH1 or MSH2 than for MSH6 or PMS2. Gaps in current evidence include a need for large, prospective studies on unselected endometrial cancer patients, and for health-economic analysis based on appropriate assumptions.

Chemoprevention of endometrial cancer in Lynch syndrome: a step forward

Lynch syndrome is one of the most common hereditary cancer syndromes. Although Lynch syndrome is associated with increased risk for developing colorectal, endometrial, and other cancers specialized screening, risk-reducing surgery, and chemoprevention offer promise for reducing morbidity and mortality. Frequent colonoscopic surveillance has proven effective for early detection and prevention of Lynch syndrome-associated colorectal cancer; however, the optimal strategy for managing endometrial cancer risks in women with germline mutations in DNA mismatch repair genes has yet to be determined. In this issue of Cancer Prevention Research, Lu and colleagues report their findings of a phase II prospective, multicenter randomized trial comparing the effects of oral contraceptive pills and Depo-Provera on endometrial proliferation in women with Lynch syndrome. Although short-term hormonal treatment with either modality altered endometrial proliferation indices, it remains unknown whether hormonal suppression actually reduces endometrial cancer risk in women with Lynch syndrome. This trial represents the first of its kind in evaluating agents which might offer protection against Lynch syndrome-associated endometrial cancer and provides preliminary data regarding potential biomarkers for early detection of endometrial neoplasia. The investigators' experience with this trial also offers insights regarding the various technical and scientific challenges inherent in chemoprevention research.