Genetic testing by cancer site: uterus

Counselling and management of women with genetic predisposition to gynaecological cancers

OBJECTIVE

To review the literature with reference to counselling and management of women with genetic predisposition to gynaecological cancers.

METHODS

Histochemical analysis, ultrasound, blood investigations, genetic testing, screening and risk-reducing surgery (RRS) are important tools for the management of gynaecological cancers and mortality reduction. Counselling can assist in timely management of gynaecological cancers. Systematic reviews, review articles, observational studies and clinical trials on PubMed, published in the English language, were included in this review.

RESULTS

The management of women with genetic predisposition to gynaecological cancers through screening tests and RRS has led to a significant decrease in the risk of malignancy through RRS in cases with BRCA1 and BRCA2 gene mutations. RRS and screening have also been found to reduce the mortality rate and increase the survival rate in women with BRCA1 and BRCA2 gene mutations. The efficacy of endometrial cancer surveillance in women with Lynch syndrome is still unproven. RRS has not been reported to be effective in women with Cowden syndrome. The risk of ovarian malignancies in individuals with germline mutations remains minimal in the general population in comparison with genetic mutations.

CONCLUSION

Genetic testing and RRS should be implemented in addition to genetic counselling for proper management and mortality reduction of women predisposed to gynaecological cancers.

Missing a chance to prevent: disparities in completion of genetic evaluation in high-risk patients with endometrial cancer

OBJECTIVE

The primary goal of this study is to examine disparities in high-risk endometrial cancer (EC) patients in relation to rates of genetic referrals (GR), testing (GT), and counseling (GC).

METHODS

This is a retrospective analysis of patients with newly diagnosed EC between January 1, 2014 and September 1, 2020 at a single institution. Patients were defined as high-risk EC patients when they were 1) diagnosed at 50 years or younger, 2) had a positive family history for cancer or 3) had evidence of loss of mismatch repair protein expression on tumor immunohistochemistry. Rates of GR, GT and GC were analyzed based on race, ethnicity, primary language and insurance status.

RESULTS

During the study period, 674 patients were diagnosed with EC and 249 (36.9%) were considered high-risk EC patients. Among high-risk patients, 128 (51.2%) were referred to GT and GC. Of those referred, 103 (80.5%) underwent GT and 85 (66.4%) completed GC. Out of all high-risk patients, 20 (18.4%) were positive for LS on GT and 29 (28.2%) had VUS results. In multivariate analysis, the odds of GT and GC referral were lower among patients who identified as Hispanic (OR=0.40; 95% CI=0.19-0.87; p=0.020). Patients who identified as black were less likely to receive GC when compared to patients of other races (p=0.030).

CONCLUSION

It is our hope that through this data we will increase awareness around existing disparities in genetic evaluation for patients with EC and ultimately create strategies to improve equitable access to care for all patients.

Clinicopathological characteristics and loss of mismatch repair protein expression in Chinese upper tract urothelial carcinomas

Expression of DNA mismatch repair (MMR) protein (MLH1, PMS2, MSH2, and MSH6) in upper tract urothelial carcinoma (UTUC) has been explored in Western cohorts, but it is rarely reported in Eastern cohorts. We aimed to assess the loss of MMR protein expression among Chinese UTUC patients and study its clinicopathological implications. We enrolled 175 UTUC patients at our center and tested the expression of MMR proteins by immunohistochemistry. Then, we explored these patients' clinicopathological characteristics. We found loss of MMR proteins in 19 (10.9%) of 175 patients in our cohort (6 MSH2 and MSH6, 2 MSH6 alone, 6 MSH2 alone, 3 MLH1 and PMS2, and 2 PMS2 alone). Loss of MMR proteins was not a significant prognostic factor of relapse-free survival for these patients. In addition, patients with lower T stage or with bladder cancer history were more likely to have loss of MMR protein expression. At last, two metastatic patients (MSH2 and MSH6 loss; MSH2 loss) with loss of MMR protein experienced tumor recession after several cycles of anti-PD-1 immunotherapy. In conclusion, this is the largest Chinese UTUC cohort study to date that explores the loss of MMR protein expression. The rate of MMR loss observed was comparable to that in the Western UTUC cohort, supporting universal UTUC screening in China. Furthermore, a subset of advanced UTUCs with MMR protein loss are probably immunogenic, for whom single or combined immunotherapy may be potential therapeutic options in the future.

Utility of germline multi-gene panel testing in patients with endometrial cancer

OBJECTIVES

Patients with germline mutations in mismatch repair genes (MLH1, MSH2, MSH6, PMS2) associated with Lynch syndrome (LS) have an increased lifetime risk of endometrial cancer (EC). Multi-gene panel testing (MGPT) is a recent hereditary cancer risk tool enabling next-generation sequencing of numerous genes in parallel. We determined the prevalence of actionable cancer predisposition gene mutations identified through MGPT in an EC patient cohort.

METHODS

A single center retrospective cohort study was conducted of patients with EC who had a clinical indication for genetic testing and who underwent MGPT as part of standard of care treatment between 2012 and 2021. Pathogenic mutations were identified and actionable mutations were defined as those with clinical management implications. Additionally, the number of individuals identified with LS was compared between MGPT and tumor-based screening.

RESULTS

The study included a total of 224 patients. Thirty-three patients [14.7%, 95% confidence interval (CI) = 10.4-20.1] had actionable mutations. Twenty-one patients (9.4%, 95% CI = 5.9-14.0) had mutations in LS genes (4 MLH1, 5 MSH2, 7 MSH6, 4 PMS2, 1 Epcam-MSH2). MGPT revealed two patients with LS (9.5% of LS cases) not identified through routine tumor-based screening. Thirteen patients (5.8%, 95% CI = 3.1-9.7) had at least one actionable mutation in a non-Lynch syndrome gene (6 CHEK2, 2 BRCA2, 2 ATM, 2 APC, 1 RAD51C, 1 BRCA1).

CONCLUSIONS

Germline MGPT is both feasible and informative as it identifies LS cases not found on tumor testing as well as additional actionable mutations in patients with EC.

In-silico analysis of Thr767Ile pathogenic variant in the MSH6 gene in family with endometrial cancer

OBJECTIVE

To examine the mechanism of pathogenity of Thr767Ile variant on MSH6 protein.

STUDY DESIGN

We describe a family diagnosed with endometrial cancer in two generations associated with variant in the MSH6 gene (p. Thr767Ile / c. 2300C>T) (rs587781462). MSH6 c. 2300C>T was associated with autosomal-dominant pattern of inheritance. MSH6 c. 2300C>T has pathogenic status in ClinVar and LOVD3 databases but it has never been described in context of hereditary endometrial cancer. We utilized a number of in-silico bioinformatic approaches using MSH6 protein sequence and structural information to assess influence of Thr767Ile on MSH6 properties.

RESULTS

MSH6 Thr767 is highly conservative amino acid among various kingdoms of organisms. Thr767Ile was predicted deleterious and likely decreases affinity of MSH2-MSH6 complex to DNA but not affect interaction between MSH2 and MSH6.

CONCLUSIONS

To the best of our knowledge, this is the first description of MSH6 T767I pathogenic variant that could be associated with a hereditary endometrial cancer. Bioinformatic analyses showed that T767I substitution most likely affects the MSH6 most important role, which is a DNA binding.

Interdisciplinary Diagnosis, Therapy and Follow-up of Patients with Endometrial Cancer. Guideline (S3-Level, AWMF Registry Nummer 032/034-OL, April 2018) - Part 1 with Recommendations on the Epidemiology, Screening, Diagnosis and Hereditary Factors of Endometrial Cancer

Summary The first German interdisciplinary S3-guideline on the diagnosis, therapy and follow-up of patients with endometrial cancer was published in April 2018. Funded by German Cancer Aid as part of an Oncology Guidelines Program, the lead coordinators of the guideline were the German Society of Gynecology and Obstetrics (DGGG) and the Gynecological Oncology Working Group (AGO) of the German Cancer Society (DKG).

Purpose The use of evidence-based, risk-adapted therapy to treat low-risk women with endometrial cancer avoids unnecessarily radical surgery and non-useful adjuvant radiotherapy and/or chemotherapy. This can significantly reduce therapy-induced morbidity and improve the patientʼs quality of life as well as avoiding unnecessary costs. For women with endometrial cancer and a high risk of recurrence, the guideline defines the optimal surgical radicality together with the appropriate chemotherapy and/or adjuvant radiotherapy where required. The evidence-based optimal use of different therapeutic modalities should improve survival rates and the quality of life of these patients. The S3-guideline on endometrial cancer is intended as a basis for certified gynecological cancer centers. The aim is that the quality indicators established in this guideline will be incorporated in the certification processes of these centers.

Methods The guideline was compiled in accordance with the requirements for S3-level guidelines. This includes, in the first instance, the adaptation of source guidelines selected using the DELBI instrument for appraising guidelines. Other consulted sources include reviews of evidence which were compiled from literature selected during systematic searches of literature databases using the PICO scheme. In addition, an external biostatistics institute was commissioned to carry out a systematic search and assessment of the literature for one area of the guideline. The identified materials were used by the interdisciplinary working groups to develop suggestions for Recommendations and Statements, which were then modified during structured consensus conferences and/or additionally amended online using the DELPHI method with consent being reached online. The guideline report is freely available online.

Recommendations Part 1 of this short version of the guideline presents recommendations on epidemiology, screening, diagnosis and hereditary factors, The epidemiology of endometrial cancer and the risk factors for developing endomentrial cancer are presented. The options for screening and the methods used to diagnose endometrial cancer including the pathology of the cancer are outlined. Recommendations are given for the prevention, diagnosis, and therapy of hereditary forms of endometrial cancer.

Universal screening of both endometrial and colon cancers increases the detection of Lynch syndrome

BACKGROUND

Lynch syndrome (LS) is the most common hereditary cause of colorectal cancer (CRC) and endometrial cancer (EC). Screening of all CRCs for LS is currently recommended, but screening of ECs is inconsistent. The objective of this study was to determine the added value of screening both CRC and EC tumors in the same population.

METHODS

A prospective, immunohistochemistry (IHC)-based screening program for all patients with newly diagnosed CRCs and ECs was initiated in 2011 and 2013, respectively, at 2 centers (primary and tertiary). Genetic testing was recommended for those who had tumors with absent mutS homolog 2 (MSH2), MSH6, or postmeiotoic segregation increased 2 (PMS2) expression and for those who had tumors with absent mutL homolog 1 (MLH1) expression and no v-Raf murine sarcoma viral oncogene homolog B (BRAF) mutation or MLH1 promoter methylation. Amsterdam II criteria, revised Bethesda criteria, and scores from prediction models for gene mutations (the PREMM1,2,6 and PREMM5 prediction models) were ascertained in patients with LS.

RESULTS

In total, 1290 patients with CRC and 484 with EC were screened for LS, and genetic testing was recommended for 137 patients (10.6%) and 32 patients (6.6%), respectively (P = .01). LS was identified in 16 patients (1.2%) with CRC and in 8 patients (1.7%) with EC. Among patients for whom genetic testing was recommended, the LS diagnosis rate was higher among those with EC (25.0% vs 11.7%, P = .052). The Amsterdam II criteria, revised Bethesda criteria, and both PREMM calculators would have missed 62.5%, 50.0%, and 12.5% of the identified patients with LS, respectively.

CONCLUSIONS

Expanding a universal screening program for LS to include patients who had EC identified 50% more patients with LS, and many of these patients would have been missed by risk assessment tools (including PREMM5 ). Universal screening programs for LS should include both CRC and EC. Cancer 2018. © 2018 American Cancer Society.

Missed opportunities: Genetic counseling and testing among an ethnically diverse cohort of women with endometrial cancer

OBJECTIVES

Lynch syndrome (LS) accounts for the majority of inherited endometrial cancers (EC), and the identification of probands presents a unique opportunity to treat and prevent multiple cancers. The diagnosis of EC can provide the indication for women with specific risk factors to undergo genetic testing (GT). We sought to evaluate genetic counseling referrals (GCR) and subsequent GT rates in an ethnically diverse group of high-risk women.

METHODS

All women diagnosed with EC between 2011 and 2016 were identified. Risk factors for LS including age, family and personal histories of Lynch-related cancers and loss of tumor mismatch repair (MMR) protein expression were identified from laboratory and medical records. Standard two-sided statistical tests were used.

RESULTS

Of 583 women diagnosed with EC, 184 (31.6%) were found to have at least one high-risk characteristic for LS. Among these high-risk women, 58% were given GCR and resulting in only 35% undergoing GT. Ten of the 65 high-risk women who had GT (15.4%) were diagnosed with Lynch syndrome, and all ten met high-risk criteria. Two women of Asian race had tumors exhibiting retained MMR protein expression despite germline testing demonstrating Lynch syndrome.

CONCLUSIONS

Many high-risk women do not receive GCR despite a high rate of germline mutations among these women. Improving GCR among high-risk women will lead to more subsequent GT to identify more Lynch syndrome families and prevent additional cancers. Among our ethnically diverse cohort, two women diagnosed with LS had retained MMR protein expression. GCR should be offered to women who possess high-risk characteristics despite normal MMR protein expression.

Prevalence and prognostic role of mismatch repair gene defect in endometrial cancer patients

The study was to evaluate the prevalence of mismatch repair gene defect among Thai patients with endometrial cancer and its association with clinico-pathological features and survivals. The formalin fixed paraffin-embedded blocks of EMC tissue from hysterectomy specimens of patients having surgery in our institution between 1 Jan 1995 and 31 December 2016 were assessed for the immunohistochemical expression of 4 mismatch repair proteins (MLH1, PMS, MSH2, MSH 6). Mismatch repair gene defect was determined by a negative expression of at least 1 protein. Among 385 EMC patients included in the study, mean age was 57.3 ± 10.8 years with 62.3% aged ⩽ 60 years. The most frequent mismatch repair gene defect was MSH6 (38.7%), followed by PMS2 (34.3%), MLH1 (33.2%), and MSH2 (16.4%). Overall, 55.1% showed negative expression of at least one protein. We found significantly higher mismatch repair gene defect in patients aged ⩽ 60 years, with early stage disease, and negative lymph node status than the other comparative groups: 59.2% vs 48.3% for age (p = 0.037), 58.2% vs 45.2% (p = 0.027) for stage, and 58.1% vs 44.6% (p = 0.048) for nodal status. The 5-year progression-free survival, overall survival, and endometrial cancer-specific survival of patients with mismatch repair gene defect was higher than those without gene defect. The differences were statistically significant for only progression-free survival and endometrial cancer-specific survival: 87.7% (95% confidence interval = 83.0%-92.4%) vs 81.5% (95% confidence interval = 75.4%-87.6%) (p = 0.049) for progression-free survival and 91.0% (95% confidence interval = 86.9%-95.1%) vs 85.5% (95% confidence interval = 80.0%-91.0%) (p = 0.044) for endometrial cancer-specific survival, respectively. In conclusion, more than half of Thai endometrial cancer patients had mismatch repair gene defect. The patients with mismatch repair gene defect had significantly younger age (⩽ 60 years) and better prognosis in terms of early stage, negative nodal status, and longer survivals.

Molecular Pathology: Predictive, Prognostic, and Diagnostic Markers in Uterine Tumors

This article focuses on the diagnostic, prognostic, and predictive molecular biomarkers in uterine malignancies, in the context of morphologic diagnoses. The histologic classification of endometrial carcinomas is reviewed first, followed by the description and molecular classification of endometrial epithelial malignancies in the context of histologic classification. Taken together, the molecular and histologic classifications help clinicians to approach troublesome areas encountered in clinical practice and evaluate the utility of molecular alterations in the diagnosis and subclassification of endometrial carcinomas. Putative prognostic markers are reviewed. The use of molecular alterations and surrogate immunohistochemistry as prognostic and predictive markers is also discussed.

Evaluation of Metachronous Breast and Endometrial Cancers: Preroutine and Postroutine Adjuvant Tamoxifen Use

BACKGROUND

The time interval between diagnoses of breast cancer (BC) and endometrial cancer (EC) is not well established in women with metachronous primary tumors. We sought to examine this interval and identify associations with treatment-related and clinicopathologic factors.

METHODS

We identified 141 patients who developed both cancers during 1966 to 2013. Patients were divided into 2 groups: group 1, BC first, and group 2, EC first. Subanalysis performed of group 1 (59 patients) stratified around adjuvant tamoxifen use: pre-1990 BC diagnosis and post.

RESULTS

Fifty-nine and 82 patients were in groups 1 and 2, respectively. The mean time interval was comparable (76 vs 74 months, P = 0.861). Subanalysis divided group 1 into pre- (n = 27) and post- (n = 32) 1990 and resulted in different mean time intervals between diagnosis of metachronous cancers (106 vs 50 months, respectively [P = 0.042]). Median progression-free survival (PFS) and overall survival (OS) for EC were longer in the pre group (PFS, 51 vs 26 months [P = 0.169]; OS, 59 vs 27 months [P = 0.190]). Median PFS and OS for BC were also longer in this group (PFS, 147 vs 109 months [P = 0.005]; OS, 166 vs 114 months [P < 0.001]).

CONCLUSIONS

Our data indicate the mean time interval between the diagnosis of EC and BC was approximately 6 years. Disease-specific EC survival was worse for patients with a previous diagnosis of BC. Stratification around implementation of tamoxifen use shows comparable grade and stage but different time interval and survival, suggesting resulting effects from adjuvant therapy for BC. These results are useful in counseling women at risk.

The genetic prediction of risk for gynecologic cancers

Salient to the intent of personalized medicine, hereditary cancer syndromes present significant opportunities in the treatment and prevention of some gynecologic cancers. Mutations in BRCA1, BRCA2, and DNA mismatch repair genes: MLH1, MSH2, MSH6, and PMS2 are important causal agents in hereditary breast and ovarian cancer (HBOC) and Lynch syndromes. Though they only account for an estimated 10-18% of ovarian, tubal, peritoneal, and endometrial cancer cases, inherited cancers are imminently preventable if mutation carriers are identified in a timely manner. Population level screening is currently impractical due to low prevalence of disease, cost of testing, and ethical issues associated with testing, so diagnosis of these mutations is limited. Being affected by one of the heritable gynecologic malignancies is a logical entry point into the genetic counseling and testing pipeline for the patient and her family members. Thus, gynecologic cancer providers are uniquely positioned to diagnose germline mutations that can inform prognosis and treatment for their patients in addition to enabling prevention for patients' cancer-unaffected blood relatives, or "previvors". The purpose of this review is to describe our current perspective on testing for and implications of heritable cancer syndromes in the women with ovarian, tubal, peritoneal, and endometrial cancers.

Hereditary Syndromes Manifesting as Endometrial Carcinoma: How Can Pathological Features Aid Risk Assessment?

Endometrial carcinoma is the most common gynecological tumor worldwide. It can be the presenting malignancy, acting as the harbinger, of an undiagnosed hereditary syndrome. Up to 50% of females with Lynch syndrome present in this manner. Differentiation between Lynch, Muir-Torre, and Cowden syndromes can at times be challenging due to the overlapping features. Our review emphasizes on the strengths, pitfalls, and limitations of microscopic features as well as immunohistochemical and polymerase chain reaction- (PCR-) based tests used by laboratories to screen for DNA mismatch repair (MMR) and PTEN gene mutations in patients to enable a more targeted and cost effective approach in the use of confirmatory gene mutational analysis tests. This is crucial towards initiating timely and appropriate surveillance measures for the patient and affected family members. We also review the evidence postulating on the possible inclusion of uterine serous carcinoma as part of the spectrum of malignancies seen in hereditary breast and ovarian carcinoma syndrome, driven by mutations in BRCA1/2.

The mutational landscape of endometrial cancer

Globally, endometrial carcinoma causes about 74000 deaths annually. Endometrial carcinomas can be classified into several histological subtypes including endometrioid and serous histologies. Over the course of the past two years, a number of studies have decoded the exomes of endometrioid and serous endometrial carcinomas revealing novel somatically mutated genes that are likely to drive their development. Moreover, an integrated genomic analysis of these two histological subtypes by The Cancer Genome Atlas has led to their molecular reclassification into four discrete molecular subgroups. Collectively, these genomic advances set the stage for future biological and clinical studies to determine their relevance for patient care.

Mismatch repair protein expression in 1049 endometrial carcinomas, associations with body mass index, and other clinicopathologic variables

OBJECTIVE

Links between obesity, with its attendant estrogen abnormalities, and the endometrial carcinoma (EC) DNA Mismatch Repair Protein (MMR) system have recently been proposed. We investigated relationships between body mass index (BMI) and clinicopathological correlates including MMR expression in a large single institution EC cohort.

METHODS

Clinical and pathological databases from 2007 to 2012 were used to identify consecutive hysterectomy specimens with EC. Univariate and multivariate analyses were used to explore relationships between BMI, age, stage, tumor type and immunohistochemical results for MLH1, PMS2, MSH2 and MSH6.

RESULTS

1049 EC were identified. Overall, BMI was higher amongst women with normal MMR (p=0.002). However, when stratified by age and specific MMR, statistically significant differences localized exclusively to women <50years old with loss of MSH2 and/or MSH6 (p=0.003 and p=0.005 respectively). Higher BMI correlated with endometrioid FIGO 1 and 2 tumors (p<0.001) and with stage 1a (p<0.001). Conversely, MMR abnormalities did not show significant associations with stage (p=0.302) or histologic grade (p=0.097).

CONCLUSIONS

BMI showed statistically significant associations with MMR expression, tumor grade and stage amongst 1049 consecutive EC. Obesity correlates with lower grade and stage EC. A link between BMI and maintenance of the MMR system is not supported by our data because the only statistically significant association occurred in women <50years old with MSH2 and/or MSH6 abnormalities where Lynch syndrome related cases are expected to cluster.

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.