Lynch syndrome in women less than 50 years of age with endometrial cancer

The Role of Immunohistochemistry Markers in Endometrial Cancer with Mismatch Repair Deficiency: A Systematic Review

The objective of this systematic review was to summarize our current knowledge of the role of immunohistochemistry (IHC) markers for identifying mismatch repair-deficient (MMRd) tumors in endometrial cancer (EC). Identification of MMRd tumors, which occur in 13% to 30% of all ECs, has become critical for patients with colorectal and endometrial cancer for therapeutic management, clinical decision making, and prognosis. This review was conducted by two authors applying the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines using the following terms: “immunohistochemistry and microsatellite instability endometrial cancer” or “immunohistochemistry and mismatch repair endometrial cancer” or “immunohistochemistry and mismatch repair deficient endometrial cancer”. Among 596 retrieved studies, 161 fulfilled the inclusion criteria. Articles were classified and presented according to their interest for the diagnosis, prognosis, and theragnostics for patients with MMRd EC. We identified 10, 18, and 96 articles using IHC expression of two, three, or four proteins of the MMR system (MLH1, MSH2, MHS6, and PMS2), respectively. MLH1 promoter methylation was analyzed in 57 articles. Thirty-four articles classified MMRd tumors with IHC markers according to their prognosis in terms of recurrence-free survival (RFS), overall survival (OS), stage, grade, and lymph node invasion. Theragnostics were studied in eight articles underlying the important concentration of PD-L1 in MMRd EC. Even though the role of IHC has been challenged, it represents the most common, robust, and cheapest method for diagnosing MMRd tumors in EC and is a valuable tool for exploring novel biotherapies and treatment modalities.

Comprehensive Clinicopathologic Analysis for Mismatch Repair Protein Expression in Unselected Endometrial Carcinoma Patients With an Emphasis on the Role of MLH1 Deficiency

Screening for mismatch repair (MMR) deficiency in unselected patients with endometrial carcinoma (EC) and the clinicopathologic descriptions of ECs with MMR deficiency have been well demonstrated in Western populations, but studies on Asian populations are relatively scarce. In this study, we described the clinicopathologic features of ECs according to MMR status in unselected Taiwanese patients. We also conducted subgroup analysis of MMR-deficient (dMMR) cases according to the presence or absence of MLH1. Patients diagnosed with ECs between January 2017 and February 2020 at our institution were included. Immunohistochemistry analysis of MLH1, PMS2, MSH2, and MSH6 proteins on endometrial primary tumors and clinicopathologic variables were assessed retrospectively. A total of 231 EC patients were enrolled, of whom 50 (21.6%) had dMMR tumors. Of these 50 cases, 39 had tumors that lacked MLH1 expression and 11 were positive for MLH1. The overall dMMR group was significantly related to older age, parity, and high histologic grade compared with the MMR-proficient (pMMR) group. ECs with MLH1 deficiency were obviously associated with several poor pathologic features, including high histologic grade, lymph node metastasis, and lymphovascular space invasion. Moreover, we first reported that parity and the late age at menopause are strongly correlated with MLH1-related dMMR EC group compared with pMMR group. In conclusion, triaging EC patients into pMMR, MLH1-related dMMR and non-MLH1-related dMMR groups by immunohistochemistry analysis may help clinicians to predict disease behavior and guide further management. The strong association between parity and MLH1-related dMMR ECs warrants further investigation on the underlying mechanism.

Using amide proton transfer-weighted MRI to non-invasively differentiate mismatch repair deficient and proficient tumors in endometrioid endometrial adenocarcinoma

OBJECTIVES

To investigate the utility of three-dimensional (3D) amide proton transfer-weighted (APTw) imaging to differentiate mismatch repair deficient (dMMR) and mismatch repair proficient (pMMR) tumors in endometrioid endometrial adenocarcinoma (EEA).

METHODS

Forty-nine patients with EEA underwent T1-weighted imaging, T2-weighted imaging, 3D APTw imaging, and diffusion-weighted imaging at 3 T MRI. Image quality and measurement confidence of APTw images were evaluated on a 5-point Likert scale. APTw and apparent diffusion coefficient (ADC) values were calculated and compared between the dMMR and pMMR groups and among the three EEA histologic grades based on the Federation of Gynecology and Obstetrics (FIGO) grading system criteria. Student's t-test, analysis of variance with Scheffe post hoc test, and receiver operating characteristic analysis were performed. Statistical significance was set at p < 0.05.

RESULTS

Thirty-five EEA patients (9 with dMMR tumors and 26 with pMMR tumors) with good image quality were enrolled in quantitative analysis. APTw values were significantly higher in the dMMR group than in the pMMR group (3.2 ± 0.3% and 2.8 ± 0.5%, respectively; p = 0.019). ADC values of the dMMR and pMMR groups were 0.874 ± 0.104 × 10^-3 mm²/s and 0.903 ± 0.100 × 10^-3 mm²/s, respectively. No significant between-group difference was noted (p = 0.476). No statistically significant differences were observed in APTw values or ADC values among the three histologic grades (p = 0.766 and p = 0.295, respectively).

CONCLUSIONS

APTw values may be used as potential imaging markers to differentiate dMMR from pMMR tumors in EEA.

Endometrial cancer in Lynch syndrome

Lynch syndrome (LS) is an autosomal dominant inherited disease caused by germline pathogenic variants (PVs) in mismatch repair (MMR) genes. LS-associated endometrial cancer (LS-EC) is the most common extraintestinal sentinel cancer caused by germline PVs in MMR genes, including MLH1, MSH2, MSH6 and PMS2. The clinicopathologic features of LS-EC include early age of onset, lower body mass index (BMI), endometrioid carcinoma and lower uterine segment involvement. There has been significant progress in screening, diagnosis, surveillance, prevention and treatment of LS-EC. Many studies support universal screening for LS among patients with EC. Screening mainly involves a combination of traditional clinical criteria and molecular techniques, including MMR-immunohistochemistry (MMR-IHC), microsatellite instability (MSI) testing, MLH1 promoter methylation testing and gene sequencing. The effectiveness of endometrial biopsy and transvaginal ultrasound (TVS) for clinical monitoring of asymptomatic women with LS are uncertain yet. Preventive strategies include hysterectomy and bilateral salpingo-oophorectomy (BSO) as well as chemoprophylaxis using exogenous progestin or aspirin. Recent research has revealed the benefits of immunotherapy for LS-EC. The NCCN guidelines recommend pembrolizumab and nivolumab for treating patients with advanced or recurrent microsatellite instability-high (MSI-H)/mismatch repair-deficient (dMMR) EC.

Genome profiling of mismatch repair genes in eight types of tumors

Mismatch repair (MMR) plays an important role in the occurrence and development of tumors. At present, it is widely believed that MMR is a protective mechanism of tumors that plays a critical role in the progresses of cancer. In this study, 34 genes related to MMR selected from Gene Ontology (GO) database were scored by single sample Gene sets enrichment analysis (ssGSEA), and eight cancers were screened from 23 TCGA solid cancers to investigate the clinical significance of MMR score. MMR had different effects on the prognosis of the eight tumors, with a protective effect in three cancers and functioning as a risk factor in the remaining five cancers. We used unsupervised clustering to divide the patients into four clusters. We found that the immune and metabolic status of the four clusters were extremely different, among which cluster1 had the lowest tumor purity and the most complex microenvironment; this may explain its poor prognosis and immunotherapy effect. In summary, MMR scores can improve the predictive ability and provide effective guidance for immunotherapy in individual type of tumors.

Wise Management of Ovarian Cancer: On the Cutting Edge

Epithelial ovarian cancer (EOC) is the fifth leading cause of cancer mortality among women. Two-thirds of patients present at advanced stage at diagnosis, and the estimated 5 year survival rate is 20-40%. This heterogeneous group of malignancies has distinguishable etiology and molecular biology. Initially, single-gene sequencing was performed to identify germline DNA variations associated with EOC. However, hereditary EOC syndrome can be explained by germline pathogenic variants (gPVs) in several genes. In this regard, next-generation sequencing (NGS) changed clinical diagnostic testing, allowing assessment of multiple genes simultaneously in a faster and cheaper manner than sequential single gene analysis. As we move into the era of personalized medicine, there is evidence that poly (ADP-ribose) polymerase (PARP) inhibitors exploit homologous recombination (HR) deficiency, especially in breast cancer gene 1 and 2 (BRCA1/2) mutation carriers. Furthermore, extensive preclinical data supported the development of aurora kinase (AURK) inhibitors in specific tumor types, including EOC. Their efficacy may be optimized in combination with chemotherapeutic or other molecular agents. The efficacy of metformin in ovarian cancer prevention is under investigation. Certain mutations, such as ARID1A mutations, and alterations in the phosphatidylinositol 3-kinase (PI3K)/AKT/mTOR pathway, which are specific in ovarian clear cell carcinoma (OCCC) and endometrioid ovarian carcinoma (EnOC), may offer additional therapeutic targets in these clinical entities. Malignant ovarian germ cell tumors (MOGCTs) are rare and randomized trials are extremely challenging for the improvement of the existing management and development of novel strategies. This review attempts to offer an overview of the main aspects of ovarian cancer, catapulted from the molecular mechanisms to therapeutic considerations.

Endometrial cancer in young women: prognostic factors and treatment outcomes in women aged ≤40 years

OBJECTIVE

Endometrial cancer in pre-menopausal patients aged ≤40 years is rare and poses both diagnostic and management challenges. The goal of this study was to investigate the clinical and pathologic factors associated with endometrial cancer in this group and their impact on survival.

METHODS

Patients with endometrial cancer treated between January 2004 and August 2016 were retrospectively reviewed. Patients who underwent either primary surgical treatment or fertility-sparing therapy were included. Exclusion criteria were age >60 years and patients who received neoadjuvant chemotherapy or primary radiation. Age at diagnosis was used to classify patients into two groups: ≤40 and 41-60 years. Clinical and pathologic variables were compared between the groups. Progression-free survival and overall survival were estimated using Cox proportional hazards.

RESULTS

A total of 551 patients were evaluated, of which 103 (18.7%) patients were ≤40 years and 448 (81.3%) were 41-60 years. Age ≤40 years was associated with higher body mass index (38.8 vs 35.8 kg/m², p=0.008), non-invasive cancers (54.2% vs 32.6%, p<0.001), lower uterine segment involvement (27.2% vs 22.5%, p<0.001), and less lymphovascular space invasion (16.8% vs 29.1%, p=0.015). The rate of synchronous ovarian cancer was 9.2% vs 0.7% in age 41-60 years (p<0.001), and 19% of women with endometrial cancer aged ≤40 years underwent fertility-sparing therapy. Grade, stage, myometrial invasion, lymphovascular space invasion, and lymph node status were associated with survival, and fertility-sparing therapy adversely affected the recurrence rate of the age ≤40 years cohort. Among all patients aged ≤60 years, mismatch repair deficiency due to MLH1 methylation was associated with worse progression-free survival, 48.6% vs 83.3% (HR 1.98, 95% CI 1.06 to 3.17, p=0.032), and overall survival, 56.5% vs 90.0% (HR 2.58, 95% CI 1.13 to 5.90, p=0.025).

CONCLUSIONS

Patients aged ≤40 years with endometrial cancer have more favorable prognostic factors and higher rates of synchronous tumors. Fertility-sparing therapy was associated with higher recurrence rates. The prognostic value of MLH1 methylation in this population warrants further investigation.

Mismatch repair deficiency/microsatellite instability-high as a predictor for anti-PD-1/PD-L1 immunotherapy efficacy

Immunotherapies have led to substantial changes in cancer treatment and have been a persistently popular topic in cancer research because they tremendously improve the efficacy of treatment and survival of individuals with various cancer types. However, only a small proportion of patients are sensitive to immunotherapy, and specific biomarkers are urgently needed to separate responders from nonresponders. Mismatch repair pathways play a vital role in identifying and repairing mismatched bases during DNA replication and genetic recombination in normal and cancer cells. Defects in DNA mismatch repair proteins and subsequent microsatellite instability-high lead to the accumulation of mutation loads in cancer-related genes and the generation of neoantigens, which stimulate the anti-tumor immune response of the host. Mismatch repair deficiency/microsatellite instability-high represents a good prognosis in early colorectal cancer settings without adjuvant treatment and a poor prognosis in patients with metastasis. Several clinical trials have demonstrated that mismatch repair deficiency or microsatellite instability-high is significantly associated with long-term immunotherapy-related responses and better prognosis in colorectal and noncolorectal malignancies treated with immune checkpoint inhibitors. To date, the anti-programmed cell death-1 inhibitor pembrolizumab has been approved for mismatch repair deficiency/microsatellite instability-high refractory or metastatic solid tumors, and nivolumab has been approved for colorectal cancer patients with mismatch repair deficiency/microsatellite instability-high. This is the first time in the history of cancer therapy that the same biomarker has been used to guide immune therapy regardless of tumor type. This review summarizes the features of mismatch repair deficiency/microsatellite instability-high, its relationship with programmed death-ligand 1/programmed cell death-1, and the recent advances in predicting immunotherapy efficacy.

The proportion of endometrial cancers associated with Lynch syndrome: a systematic review of the literature and meta-analysis

Purpose

Endometrial cancer (EC) is often the sentinel cancer in women with Lynch syndrome (LS). However, efforts to implement universal LS screening in EC patients have been hampered by a lack of evidence detailing the proportion of EC patients that would be expected to screen positive for LS.

Methods

Studies were identified by electronic searches of Medline, Embase, Cochrane CENTRAL and Web of Science. Proportions of test positivity were calculated by random and fixed-effects meta-analysis models. I² score was used to assess heterogeneity across studies.

Results

Fifty-three studies, including 12,633 EC patients, met the inclusion criteria. The overall proportion of endometrial tumors with microsatellite instability or mismatch repair (MMR) deficiency by immunohistochemistry (IHC) was 0.27 (95% confidence interval [CI] 0.25–0.28, I²: 71%) and 0.26 (95% CI 0.25–0.27, I²: 88%), respectively. Of those women with abnormal tumor testing, 0.29 (95% CI 0.25–0.33, I²: 83%) had LS-associated pathogenic variants on germline testing; therefore around 3% of ECs can be attributed to LS. Preselection of EC cases did increase the proportion of germline LS diagnoses.

Conclusion

The current study suggests that prevalence of LS in EC patients is approximately 3%, similar to that of colorectal cancer patients; therefore our data support the implementation of universal EC screening for LS.

Endometrial cancer risk and survival by tumor MMR status

Objective

The risk of developing endometrial cancer (EC) and/or survival following a diagnosis of EC might differ by tumor DNA mismatch repair (MMR) status. We assessed the association between tumor MMR status (classified as MMR-proficient, somatic MMR-deficient, germline MMR-deficient) and the risk of developing EC and survival following a diagnosis of EC.

Methods

We analyzed data from women who participated in the Australian National Endometrial Cancer Study (ANECS) conducted between 2005 and 2007. Risk analyses (698 cases/691 population controls) utilized sociodemographic and lifestyle information obtained from telephone interviews at recruitment. For survival analyses (728 cases), patients' clinical data was abstracted from medical records, and survival data were obtained via linkage with the Australian National Death Index. We used logistic regression analysis to evaluate the associations between tumor MMR status and EC risk, and proportional hazards models to perform survival analyses with adjustment of known prognostic factors.

Results

Established risk factors for EC did not differ significantly by tumor MMR status. In analyses including all EC subtypes, overall and EC-specific survival did not differ by tumor MMR status. Among women with the most common endometrioid subtype, EC-specific survival was worse for women with somatic MMR-deficient EC compared to women with MMR-proficient EC (hazard ratio [HR]=2.18; 95% confidence interval [CI]=1.19–4.01).

Conclusion

The risk of EC is not associated with MMR status. Accurate separation of germline from somatic causes of MMR deficiency suggests that patients with endometrioid subtype somatic MMR-deficient tumors have poorer EC-specific survival than those with MMR-proficient tumors, after accounting for other prognostic factors.

Somatic Testing on Gynecological Cancers Improve the Identification of Lynch Syndrome

OBJECTIVE

Recent data from the literature indicate gynecological cancers (GCs) as sentinel cancers for a diagnosis of Lynch syndrome (LS). Clinical approaches to identifying LS have low sensitivity, whereas somatic tests on GCs may be a more sensitive and cost-effective strategy.

METHODS

A series of 78 GCs belonging to 74 patients sent to the Genetic Counselling Service were investigated using microsatellite instability, immunohistochemical expression of mismatch repair (MMR) genes, and MLH1 promoter methylation.

RESULTS

The presence of microsatellite instability was observed in 67.5% of GCs, and the absence of immunohistochemical expression of at least 1 of the 4 MMR proteins was observed in 71.4% of GCs, showing 96.1% concordance between the methods. Methylation analysis using methylation specific multiplex ligation-dependent probe amplification performed on 35 samples revealed MLH1 promoter hypermethylation in 18 cases (54%). Molecular analysis identified 36 LS carriers of MMR variants (27 pathogenetic and 9 variants of uncertain significance), and, interestingly, 3 LS patients had MLH1 methylated GC.With regard to histological features, LS-related GCs included endocervical cancers and also histological types different from the endometrioid cancers. The presence of peritumoral lymphocytes in GCs was statistically associated with LS tumors.

CONCLUSIONS

Somatic analysis is a useful strategy to distinguish sporadic from LS GC. Our data allow the identification of a subset of LS patients otherwise unrecognized on the basis of clinical or family history alone. In addition, our results indicate that some clinicopathological features including age of GC diagnosis; presence of peritumoral lymphocytes; isthmic, endocervical sites, and body mass index value could be useful criteria to select patients for genetic counseling.

Molecular classification and precision therapy of cancer: immune checkpoint inhibitors

On May 23, 2017, the US Food and Drug Administration (FDA) approved a treatment for cancer patients with positive microsatellite instability-high (MSI-H) markers or mismatch repair deficient (dMMR) markers. This approach is the first approved tumor treatment using a common biomarker rather than specified tumor locations in the body. FDA previously approved Keytruda for treatment of several types of malignancies, such as metastatic melanoma, metastatic non-small-cell lung cancer, recurrent or metastatic head and neck cancer, refractory Hodgkin lymphoma, and urothelial carcinoma, all of which carry positive programmed death-1/programmed death-ligand 1 biomarkers. Therefore, indications of Keytruda significantly expanded. Several types of malignancies are disclosed by MSI-H status due to dMMR and characterized by increased neoantigen load, which elicits intense host immune response in tumor microenvironment, including portions of colorectal and gastric carcinomas. Currently, biomarker-based patient selection remains a challenge. Pathologists play important roles in evaluating histology and biomarker results and establishing detection methods. Taking gastric cancer as an example, its molecular classification is built on genome abnormalities, but it lacks acceptable clinical characteristics. Pathologists are expected to act as "genetic interpreters" or "genetic translators" and build a link between molecular subtypes with tumor histological features. Subsequently, by using their findings, oncologists will carry out targeted therapy based on molecular classification.

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.

Comparison of lifestyle, hormonal and medical factors in women with sporadic and Lynch syndrome-associated endometrial cancer: A retrospective case-case study

Data available on lifestyle-associated hormonal and medical factors among endometrial cancer (EC)-affected women who carry the Lynch Syndrome (LS) mutation is limited. The aim of the present retrospective case study was to compare the reproductive and medical history, as well as lifestyle-associated factors, among patients with LS and sporadic EC. The study population consisted of 50 verified germline mismatch repair (MMR) gene mutation carriers diagnosed with EC, and 110 sporadic EC patients. Data were collected using postal questionnaires. Apart from the mean age at the time of the EC diagnosis (LS, 48.7 years compared with sporadic patients, 55.2 years; P<0.0001), the characteristics of sporadic and LS EC patients were similar with regard to body mass index (BMI) at age 18, 40 or at the time of the survey, and smoking and alcohol consumption. LS women reported a significantly lower rate of spontaneous abortion (P=0.043) and also more frequent use of contraceptives (P=0.004). The prevalence of co-morbidities, including diabetes, atherosclerosis, hypercholesterolemia and hypertension, was similar between the LS and the sporadic groups. A trend for a higher prevalence of endometriosis among mutation carriers was detected (16.0 vs. 8.1%, P=0.137). As anticipated, the prevalence of gastrointestinal tract, urinary tract and ovarian cancer was higher among the LS women (P<0.0001, P=0.006 and P=0.056, respectively). Co-morbidity and lifestyle-associated factors appeared to be comparable among patients with LS and sporadic EC. The reported difference in the use of contraceptives warrants further investigation. Future studies are also required to address the possible association between LS and endometriosis.

Abnormal mismatch repair and other clinicopathologic predictors of poor response to progestin treatment in young women with endometrial complex atypical hyperplasia and well-differentiated endometrial adenocarcinoma: a consecutive case series

OBJECTIVE

To report the response to progestin therapy in young women with endometrial complex atypical hyperplasia (CAH) or FIGO grade 1 endometrial adenocarcinoma (FIGO 1 EAC) based on clinicopathologic features, including abnormal DNA mismatch repair (MMR) by immunohistochemistry (IHC).

DESIGN

Consecutive case series.

SETTING

Olive View-UCLA Medical Center in Sylmar, CA, USA, and Cedars-Sinai Medical Center in Los Angeles, CA, USA.

POPULATION

Women ≤55 years old with CAH or FIGO 1 EAC.

METHODS

Response to progestin therapy in 84 consecutive patients was assessed based on clinicopathologic factors, including age, body mass index (BMI), initial histology, and IHC staining for MMR proteins.

MAIN OUTCOME MEASURES

Rates of abnormal MMR protein expression and response to progestin therapy were determined.

RESULTS

Six (7%) patients had abnormal IHC staining, of whom five (83%) had FIGO 1 EAC at initial diagnosis. Following progestin treatment, none of the endometrial lesions in patients with abnormal IHC for MMR proteins had resolution of hyperplasia or malignancy, in contrast to 41 (53%) with normal staining (P = 0.028). Age ≤40 years and initial lesion (CAH versus FIGO 1 EAC) were predictors of response to progestin; BMI was not.

CONCLUSIONS

In this cohort, 7% of women ≤55 years of age with CAH or FIGO 1 EAC had loss of MMR proteins by IHC. These patients had a higher incidence of invasive cancer and a lower incidence of resolution with progestin therapy.

TWEETABLE ABSTRACT

Abnormal MMR protein expression predicts poor response to progestins in young women with CAH or FIGO 1 EAC.

The Significance of Mismatch Repair Deficiency in Young Patients With Endometrial Cancer

The objective of this study was to identify the tumor characteristics associated with mismatch repair deficiency in young patients with endometrial carcinoma. Young patients (45 yr old or younger) with endometrial carcinoma treated by hysterectomy in our institution between July 2001 and June 2009 were identified. The clinical and pathologic data were obtained by review of clinical records. Among the 122 cases identified, paraffin sections were available in 67 cases for immunohistochemical staining and frozen tissue available in 62 cases for microsatellite instability (MSI) analysis. Both paraffin sections and frozen tissue were available in 36 cases. Among the 67 cases with immunohistochemical staining, 22 (32.8%) showed loss of expression of at least 1 mismatch repair protein. Defective MLH1 or MSH2 expression was associated with poor prognostic factors, including a higher incidence of pelvic lymph nodes metastasis (P=0.018) and higher stage (P=0.022) for MLH1, and an increased risk of lymphovascular permeation (P=0.015) for MSH2. On the contrary, defective MSH6 protein expression was associated with a lower incidence of high-grade tumors (P=0.04). Among the 62 cases with MSI analysis, 12 (19.4%) tumors were classified as microsatellite-high (MSI-H), whereas 2 (3.2%) were classified as microsatellite-low (MSI-L). There was no difference in the pathologic characteristics between MSI-stable and MSI-H tumor. We concluded that defective mismatch repair expression is important in young patients with endometrial carcinoma, with MSH6 protein being most commonly affected. The phenotype resulting from defective MSH6 expression was different from that caused by MLH1 or MSH2 loss.

Efficient screening strategy for Lynch syndrome in Japanese endometrial cancer

Lynch syndrome (LS) is an inherited disorder caused by a germline mutation in the DNA mismatch repair (MMR) genes and is associated with increased risk of various cancers, particularly colorectal cancer and endometrial cancer (EC). It is significant to identify LS in EC patients for prediction and prevention of the succeeding other associated cancers. However, useful LS screening guidelines for EC have not been established. The purpose of our study is to devise an efficient and practical screening strategy for LS in EC. We designed original criteria, named "APF criteria," with lenient terms (Age of onset < 50, or Personal or Family history of associated cancers) and applied it to unselected EC patients. We performed immunohistochemistry (IHC) and the methylation assay of MutL homolog 1 (MLH1) gene promoter using the tumors of patients who met our criteria, and thus selected "suspected LS" as the candidates for genetic analyses. Of 360 EC patients, 187 (51.9%) met the APF criteria, and the tumor specimens were available from 182 out of the 187 patients. IHC revealed that expression of at least one MMR protein was absent in cell nuclei of 54 (29.6%) tumors. Of 20 tumors lacking MLH1 protein expression, 14 cases were judged sporadic EC because of the hypermethylated MLH1 promoter. We thus selected 40 (11.1%) of 360 EC patients as "suspected LS." Our strategy that consists of clinical triage and the molecular analyses is expected to improve the screening efficiency and reduce the cost of LS identification in EC.

Deficient mismatch repair: Read all about it (Review)

Defects in the DNA mismatch repair (MMR) proteins, result in a phenotype called microsatellite instability (MSI), occurring in up to 15% of sporadic colorectal cancers. Approximately one quarter of colon cancers with deficient MMR (dMMR) develop as a result of an inherited predisposition syndrome, Lynch syndrome (formerly known as HNPCC). It is essential to identify patients who potentially have Lynch syndrome, as not only they, but also family members, may require screening and monitoring. Diagnostic criteria have been developed, based primarily on Western populations, and several methodologies are available to identify dMMR tumours, including immunohistochemistry and microsatellite testing. These criteria have provided evidence supporting the introduction of reflex testing. Yet, it is becoming increasingly clear that tests have a limited sensitivity and specificity and may yet be superseded by next generation sequencing. In this review, the limitations of diagnostic criteria are discussed, and current and emerging screening technologies explained. There is now useful evidence supporting the prognostic and predictive value of dMMR status in colorectal tumours, but much less is known about their value in extracolonic tumours, that may also feature in Lynch syndrome. This review assesses current literature relating to dMMR in endometrial, ovarian, gastric and melanoma cancers, which it would seem, may benefit from large-scale clinical trials in order to further close the gap in knowledge between colorectal and extracolonic tumours.

Screening for Lynch syndrome among patients with newly diagnosed endometrial cancer: a comprehensive review

Lynch syndrome (LS) is an autosomal dominant condition characterized by an increased risk of hereditary colorectal, endometrial, ovarian, pancreatic, urinary tract, and gastric cancer.It is estimated that around 5% of all endometrial cancer (EC) cases are due to an inherited predisposition, of which LS might be the most frequent. The lifetime risk of developing EC in women with LS ranges between 40% and 71% depending on the type of mutation. In many cases, this risk may even exceed their risk of developing colon cancer. Moreover, in 60% of these women, EC will be the first primary malignancy diagnosed and the sentinel diagnosis of the syndrome. Therefore, it is essential to identify which women with EC have LS in order to allow implementation of individualized screening and preventive strategies.

Role of endometrial cancer abnormal MMR protein in screening Lynch-syndrome families

OBJECTIVE

To identify patients with endometrial cancer with potential Lynch-related DNA mismatch repair (MMR) protein expression defects and to explore the role of these defects in screening for LS.

METHODS

Endometrial cancers from 173 patients recruited to the Nanchong Central Hospital were tested for MMR (MLH1, MSH2, PMS2, and MSH6) protein expression using immunohistochemistry (IHC).

RESULTS

In the 173 tumor tissue samples, the expression loss rates of MSH6, MSH2, PMS2 and MLH1 protein were 16.18% (28/173), 12.14% (21/173), 7.51% (13/173) and 5.78% (10/173), respectively. The total loss rate of MMR protein was 29.89% (27/87). There were 19 patients with a family history of cancer, of which 18 patients demonstrated loss of expression of MMR protein. In the 22 abnormal MMR patients without family history, five families were found to have Lynch-associated cancer (colorectal cancer, endometrial cancer, ovarian cancer, stomach cancer) after follow-up for two years.

CONCLUSION

MMR proteins play an important role in the progress of endometrial cancer. The routine testing of MMR proteins in endometrial cancer can contribute to the screening of LS families, especially small families.

Endometrial Carcinoma in Women Aged 40 Years and Younger

Context.—Endometrial carcinoma is a disease of older postmenopausal women, and is relatively uncommon in patients younger than 40 years. Endometrial carcinomas in this age group may be familial, associated with Lynch syndrome, or sporadic.

Objectives.—To present our current knowledge of endometrial carcinomas in women younger than 40 years.

Data Sources.—The review is based on previously published articles on this topic.

Conclusions.—Most endometrial carcinomas that occur in this age group are associated with estrogen excess. They are usually low-grade endometrioid carcinomas that present at low stages and are associated with favorable clinical outcomes. Tumors associated with mismatch repair abnormalities and Lynch syndrome appear to be distinct, with worse prognostic factors and, possibly, clinical behavior. Conservative hormonal therapy and ovarian conservation are reasonable considerations in the management of these young patients, but carry the risk of tumor progression, recurrence, and an occult synchronous or metachronous ovarian carcinoma.

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.

Development of an integrated support system for hereditary cancer and its impact on gynecologic services

OBJECTIVE

Patients with hereditary cancer need an integrated support system. A recently launched project was evaluated in terms of its efficacy in screening patients with hereditary cancer at the gynecologic service.

METHODS

The project team comprised gynecologists, surgeons, medical geneticists, and certified genetic counselors (CGCs) in our hospital. At the gynecologic service, a newly developed self-administered family history questionnaire (SAFHQ) was given to patients with ovarian, endometrial, or breast cancer as well as a history of multiple cancers. After an interview, a CGC constructed a pedigree and evaluated the risk for hereditary cancer. Patients at risk were recommended by a gynecologist to receive further genetic counseling at the Department of Genetics according to the modified Bethesda criteria, Amsterdam II criteria, and National Comprehensive Cancer Network (NCCN) guidelines 2012 for breast-ovarian cancer syndrome (HBOC). The numbers of newly screened patients were compared before and after the project launch.

RESULTS

The SAFHQ was administered to 131 patients and 106 (81 %) pedigrees were constructed between August 2012 and July 2013. The number of newly screened patients according to the Bethesda criteria was 4 and 8 at 10 years before and 1 year after the project launch, respectively. Two and 31 patients met the NCCN criteria for HBOC excluding ovarian cancer alone, respectively, at these 2 time points. Of 54 patients who were recommended to undergo further counseling, 10 (19 %) visited the Department of Genetics.

CONCLUSION

After the launch of an integrated support system, the number of patients with hereditary cancers who were screened increased. The gynecologic service played a pivotal role in patient and family care.

Tissue identity testing of cancer by short tandem repeat polymorphism: pitfalls of interpretation in the presence of microsatellite instability

Tissue identity testing by short tandem repeat (STR) polymorphism offers discriminating power in resolving tissue mix-up or contamination. However, one caveat is the presence of microsatellite unstable tumors, in which genetic alterations may drastically change the STR wild-type polymorphism leading to unexpected allelic discordance. We examined how tissue identity testing results can be altered by the presence of microsatellite instability (MSI). Eleven cases of MSI-unstable (9 intestinal and 2 endometrial adenocarcinomas) and 10 cases of MSI-stable tumors (all colorectal adenocarcinomas) were included. All had been previously tested by polymerase chain reaction testing at 5 National Cancer Institute (NCI) recommended MSI loci and/or immunohistochemistry for DNA mismatch repair proteins (MLH1, MSH2, MSH6, and PMS2). Tissue identity testing targeting 15 STR loci was performed using AmpF/STR Identifiler Amplification. Ten of 11 MSI-unstable tumors demonstrated novel alleles at 5 to 12 STR loci per case and frequently with 3 or more allelic peaks. However, all affected loci showed identifiable germline allele(s) in MSI-high tumors. A wild-type allelic profile was seen in 7 of 10 MSI-stable tumors. In the remaining 3 cases, isolated novel alleles were present at a unique single locus in addition to germline alleles. Loss of heterozygosity was observed frequently in both MSI-stable (6/11 cases) and MSI-unstable tumors (8/10 cases). In conclusion, MSI may significantly alter the wild-type allelic polymorphism, leading to potential interpretation errors of STR genotyping. Careful examination of the STR allelic pattern, high index of suspicion, and follow-up MSI testing are crucial to avoid erroneous conclusions and subsequent clinical and legal consequences.

Cancerous 'floater': a lesson learned about tissue identity testing, endometrial cancer and microsatellite instability

A 46-year-old woman presented with endometrial cells on a pap smear and underwent endometrial curettage. The specimen revealed secretory endometrium and a possible endometrial polyp. In addition, a single 4 mm fragment of well-differentiated adenocarcinoma was found. Tissue identity DNA genotyping was performed and the adenocarcinoma tissue fragment showed a drastically different allelic pattern from that of the background endometrium. To confirm tissue contamination, genotyping of three other tumor specimens-probable sources for a contaminant-was performed but failed to identify a match. Without confirmation of contamination, a second endometrial curettage was obtained from the patient, in which similar adenocarcinoma tissue was once again found. Further workup demonstrated that the patient had a microsatellite unstable (MSI) endometrial adenocarcinoma by immunohistochemistry and molecular testing. The patient subsequently underwent staging surgery, which revealed an early-stage, well-differentiated endometrioid adenocarcinoma. This case study illustrates an uncommon, yet important caveat of tissue identity testing by DNA genotyping, where MSI instability can significantly alter the allelic pattern of DNA polymorphisms in the tumor genome, leading to erroneous conclusion regarding the tissue identity. Awareness of this phenomenon is crucial for a molecular pathologist to avoid interpretation errors of tissue identity testing in a cancer diagnostic workup.

Women 50 Years Or Younger With Endometrial Cancer: The Argument for Universal Mismatch Repair Screening and Potential for Targeted Therapeutics

Objective

To identify young patients with endometrial cancer with potential Lynch-related DNA mismatch repair (MMR) protein expression defects and stathmin (STMN1) expression (part of the phosphoinositol 3-kinase pathway) and to correlate clinical data.

Methods

This retrospective study included women with endometrial cancer who were 50 years or younger at diagnosis. Clinical data were abstracted from chart review. Immunohistochemistry for MMR protein expression, STMN1, and pSTMN1 was performed and univariate analyses performed.

Results

The mean age of 111 patients was 43 years, and the mean body mass index was 39.6 kg/m2. The majority of the endometrial cancers were endometrioid histology (87.4%), International Federation of Gynecology and Obstetrics stage I (73%) and grade 1 (58.6%). Loss of at least one MMR protein on immunohistochemistry was identified in 26% to 41% of patients depending on stringency. Women with loss of MMR protein expression were compared to women with intact tumor protein expression and were less likely to be stage I (58.6% vs 78.0%; P = 0.043), more likely to have grade 3 tumors (32.1% vs 13.9%; P = 0.034), had larger tumors (6.2 vs 3.7 cm; P < 0.001), had positive lymph nodes more often (24.1% vs 3.7%; P < 0.001), and more often reported a first-degree relative with colon cancer (17.2% vs 1.2%; P < 0.001). There were no significant differences in age, weight, body mass index, medical comorbidities, recurrence, or survival. Women with high STMN1 staining had significantly more grade 3 tumors (56.3% vs 15.8%; P = 0.001), more stage III/IV disease (37.5% vs 15.8%; P = 0.04), had higher mean percentage of myometrial invasion (38.9% vs 16.7%; P = 0.003), and more lymphovascular space invasion (43.8% vs 13.7%; P = 0.004).

Conclusions

Clinical factors failed to differentiate between patients with intact or missing MMR protein expression, which supports universal screening for Lynch-associated protein defects in young women with endometrial cancer. Additionally, STMN1 staining may identify more aggressive tumors, which might benefit from more aggressive treatments or targeted treatment options.

Histologic evaluation of prophylactic hysterectomy and oophorectomy in Lynch syndrome

Women with Lynch syndrome (LS) are at increased risk for endometrial (EC) and ovarian carcinoma (OC). Current surveillance recommendations for detection of EC and OC in LS patients are not effective. Small studies have shown that prophylactic hysterectomy and bilateral salpingo-oophorectomy (P-TH-BSO) are the most effective and least expensive preventive measures in these patients. Data regarding histologic findings in prophylactic specimens in these patients are lacking. All LS patients who underwent P-TH-BSO at the Memorial Sloan-Kettering Cancer Center from 2000 to 2011 were identified. Slides were evaluated for the presence of endometrial hyperplasia (EH), EC, OC, or any other recurrent histologic findings. Twenty-five patients were identified, with an age range of 36 to 61 years. Fifteen patients had a synchronous or prior colorectal carcinoma, and 2 patients had a history of sebaceous carcinoma. Focal FIGO grade 1 endometrioid ECs were detected in 2 patients; 1 was 54 years of age (MSH2 mutation; superficially invasive), and the other was 56 years of age (MLH1 mutation; noninvasive). Focal complex atypical hyperplasia, unassociated with carcinoma, was seen in 3 patients, ages 35 and 45 (MLH1 mutations) and 53 years (MSH2 mutation). One patient (44 y, with MSH2 mutation) was found to have a mixed endometrioid/clear cell OC and simple EH without atypia. The OC was adherent to the colon but did not show distant metastasis. In our study, P-TH-BSOs performed because of the presence of LS revealed incidental EC and/or EH in 24% of cases and OC in 4%. The ECs were low grade, confined to the endometrium, and seen in patients older than 50 years. Prophylactic hysterectomy allows detection of early lesions in LS; these lesions appear to be small and focal. This small series of prophylactic hysterectomies may provide some clues about LS-associated endometrial carcinogenesis.

Survival of endometrial cancer patients with lymphatic invasion and deficient mismatch repair expression

OBJECTIVE

This study examines patients under the age of 70 with endometrial cancer and lymphatic invasion or lymph node metastases. Survival of patients with loss of tumor mismatch repair expression is compared to survival of patients with normal mismatch repair expression.

METHODS

This is a retrospective review of patients treated from 1998-2009 for carcinoma of the endometrium. All patients with lymphatic invasion, including lymph node metastases, had immunohistochemical staining of the primary tumor for loss of expression of the mismatch repair genes MLH1, PMS2, MSH6, and MSH2. Overall survival and disease specific survival were compared using Kaplan-Meier plots.

RESULTS

Sixty-six patients were identified for inclusion; 26 demonstrated loss of mismatch repair expression and 40 demonstrated normal mismatch repair expression. Overall survival and disease specific survival were significantly better in the group with defective mismatch repair expression. Subgroup analysis of FIGO stage 3C patients also showed significantly better survival in patients with deficient mismatch repair expression.

CONCLUSION

For patients with endometrial cancer and lymphatic invasion, patients demonstrating loss of mismatch repair expression in the primary tumor appear to have a significantly better survival than patients with normal mismatch repair expression. Further investigation appears warranted to examine a possible role of mismatch repair expression as a prognostic marker for high risk patients with endometrial cancer.

Correlation between body mass index and prevalence of hereditary nonpolyposis colorectal cancer in Korean patients with endometrial cancer

OBJECTIVE

The purpose of the study was to investigate the relationship between body mass index (BMI) and hereditary nonpolyposis colorectal cancer (HNPCC) in Korean women with endometrial cancer.

METHODS

Among 227 patients with endometrial cancer in the study population, 20 patients (8.8%) had HNPCC. The patients were divided into 2 groups based on the BMI: nonobese (BMI ≤25 kg/m) and obese (BMI >25 kg/m); then the nonobese group was subdivided into 2 groups: normal weight (BMI <23 kg/m) and overweight (BMI, 23-25 kg/m). The distributions of BMI categories were compared between patients with sporadic endometrial cancer and with HNPCC-related endometrial cancer.

RESULTS

Among 207 patients with sporadic endometrial cancer, 119 (57.5%) were nonobese and 88 patients (42.5%) were obese. Of 20 patients with endometrial cancer related to HNPCC, 10 (50.0%) were nonobese and 10 (50.0%) were obese. In a subgroup analysis of only nonobese patients, 68 patients with sporadic endometrial cancer had normal weight and 51 were overweight. On the other hand, all 10 patients with HNPCC related to endometrial cancer had normal weight. There was no significant difference between the group with HNPCC-related endometrial cancer and the group with sporadic endometrial cancer according to BMI (P = 0.221). However, BMI proportions in HNPCC related to endometrial cancer were significantly different from those in sporadic endometrial cancer (P = 0.016). Among a subgroup of nonobese patients, the proportion of normal weight was significant higher in patients with HNPCC-related endometrial cancer compared to those in sporadic endometrial cancer (P = 0.006).

CONCLUSION

Body mass index was not different between sporadic endometrial cancer and HNPCC-related endometrial cancer in Koreans. However, BMI proportions in the patients with HNPCC related to endometrial cancer was significantly different from those in sporadic endometrial cancer. Specifically, among nonobese patients, the proportion of normal weight was significantly high in Korean women with HNPCC.

Hereditary colon cancer syndromes

Colon cancer is associated with a family history in up to 25% of cases. As many as 5% are associated with an established hereditary syndrome, demonstrating the profound influence of inheritable genetic mechanisms in the development of this disease. These syndromes confer a diverse spectrum of risk, age of presentation, endoscopic and histological findings, extracolonic manifestations, and modes of inheritance. As the molecular characteristics of these disorders become better described, enhanced genotype-phenotype correlations may offer a more targeted approach to diagnosis, screening, and surveillance. While the strategies for diagnosis and management of familial adenomatous polyposis (FAP) and Lynch syndrome are more established, the approach to newly recognized syndromes such as MUTYH-associated polyposis (MAP) and hyperplastic polyposis syndromes continues to evolve. Effective cancer prevention in affected individuals and at-risk family members first requires timely recognition of these hereditary colon cancer syndromes followed by integration of genetic testing and clinical examinations.

Clinical cancer genetics: Part I: Gastrointestinal

There is an increasing recognition of the importance of genetic and familial cancer syndromes in routine clinical practice. Although most of gastrointestinal cancers are sporadic, a number of important cancer predisposition syndromes are now recognized and well characterized. In this review, we discuss some of the basic principles of clinical cancer genetics and clinically relevant aspects of the more common gastrointestinal cancer syndromes from the perspective of practicing radiation oncologists.

When brachytherapy met genetic oncology. Can radiation oncologists improve the detection of hereditary non-polyposis colorectal cancer?

Between January 1994 and December 2004, 696 patients with localized endometrial carcinoma have been treated at the Institute Jean-Godinot. Patients were selected on the following criteria: histologically proven adenocarcinoma of the endometrium; age at onset under 60 years; patient not deceased at the time of the study. One hundred twelve patients met these criteria and received a mailed specific questionnaire to establish their pedigree. Thirty-one patients (35.5%) were eventually found eligible for a genetic counselling but only 13 patients agreed to be informed later on. According to the obtained pedigrees and MSI test results, 7 genetic tests have been carried out and so far, 3 MMR mutations were detected. This study suggested the feasibility of a step by step screening of endometrial cancers to select patients at risk for Lynch syndrome and for whom a genetic test would be recommended. Authors suggest that either Amsterdam or Bethesda criteria should be systematically used prospectively in every newly diagnosed endometrial cancer and retrospectively using clinical databases available on endometrial cancers.

Clinical and histomolecular endometrial tumor characterization of patients at-risk for Lynch syndrome in South of Brazil

Lynch syndrome is an autosomal dominant cancer predisposition syndrome caused by germline mutations in one of the mismatch repair (MMR) genes: MLH1, MSH2, MSH6 and PMS2. Clinically, Lynch syndrome is characterized by early onset (45 years) of colorectal cancer (CRC), as well as extra-colonic cancer. Male and female carriers of Lynch syndrome-associated mutations have different lifetime risks for CRC and in women endometrial cancer (EC) may be the most common tumor. Whenever Amsterdam criteria are not fulfilled, the currently recommended laboratory screening strategies involve microsatellite instability testing and immunohistochemistry staining of the tumor for the major MMR proteins. The aim of this study was to estimate the frequency of MMR deficiencies in women diagnosed with EC who are at-risk for Lynch syndrome. Thirty women diagnosed with EC under the age of 50 years and/or women with EC and a first degree relative diagnosed with a Lynch syndrome-associated tumor were included. To assess MMR deficiencies four methods were used: multiplex PCR, Single Strand Conformation Polymorphism, Immunohistochemistry and Methylation Specific-Multiplex Ligation-dependent Probe Amplification. Twelve (40%) patients with EC fulfilling one of the inclusion criteria had results indicative of MMR deficiency. The identification of 5 women with clear evidence of MMR deficiency and absence of either Amsterdam or Bethesda criteria among 10 diagnosed with EC under the age of 50 years reinforces previous suggestions by some authors that these women should be considered at risk and always screened for Lynch syndrome after informed consent.

Hereditary breast and ovarian cancer (HBOC): clinical features and counseling for BRCA1 and BRCA2, Lynch syndrome, Cowden syndrome, and Li-Fraumeni syndrome

This article provides an overview of the molecular changes associated with inherited gynecologic malignancies and the incorporation of this information in the counseling of individuals at increased risk for developing malignancies, as well as conventional and emerging approaches to the screening of the general population. Cancer genetic counseling and its role in women's health care is examined. The focus is hereditary breast and ovarian cancer; however, cancer predisposition caused by genes other than BRCA1 and BRCA2 is also considered. The aim is to provide a foundation for counseling based on fundamental knowledge of the genes and their clinical consequences. The reader is then guided through the mechanics of risk assessment for individual patients, concluding with the psychosocial implications of counseling.

Clinicopathological features in endometrial carcinoma associated with Lynch syndrome in China

OBJECTIVE

To study the clinicopathological characteristics of Lynch syndrome-associated endometrial carcinoma in China.

METHODS

Twenty-seven patients who fulfilled Amsterdam criteria II were classified as having Lynch syndrome-associated endometrial carcinoma (group A), and 331 patients without a family history of cancer were classified as having sporadic endometrial carcinoma (group B).

RESULTS

There were 81 malignancies in 27 families with Lynch syndrome-associated endometrial carcinoma, including colorectal cancer (24.7%), endometrial carcinoma (21.0%), and liver (12.3%), stomach (9.9%), lung (6.2%), and breast (6.2%) cancers. Mean age at the time of diagnosis was 49.7 years in group A and 56.3 years in group B (P = 0.004). Second primary cancers occurred in 33.3% of patients in group A and 5.1% in group B (P = 0.000). The most common second primary cancers were colorectal cancer (44%) and ovarian cancer (22%). The percentage of obese patients was higher in group A (P= 0.013). There was no difference between the 2 groups in incidence of diabetes mellitus or hypertension or in histological type and International Federation of Gynecology and Obstetrics stage. The 5-year survival rates for groups A and B were 96.2% and 79.6%, respectively. Prognosis for group A was better than for group B (P = 0.045).

CONCLUSIONS

Some clinicopathological features of Lynch syndrome-associated endometrial carcinoma, such as early onset and multiple primary carcinomas are similar in the Chinese and American/European populations. However, the Chinese population had a unique family cancer distribution that included lung and breast cancers. Well-differentiated grade and good prognosis imply better biobehavior of Lynch syndrome-associated endometrial carcinoma in the Chinese population.

Insights into selected genetic diseases affecting the female reproductive tract and their implication for pathologic evaluation of gynecologic specimens

CONTEXT

Recent advances in the understanding of genetic conditions involving the female genital tract and mechanisms of carcinogenesis in this setting affect patient management and thus necessitate appropriate pathologic evaluation of specimens. In the past, specimens from prophylactic surgery were a rarity; however, they are now more frequently encountered and often require a significant variation from routine processing methods. Pathologists also receive more specimens requiring prospective workup for possible underlying genetic conditions such as microsatellite instability.

OBJECTIVE

To summarize the current knowledge of important genetic and hereditary conditions affecting the female reproductive organs while highlighting the resulting practical significance for specimen handling, "grossing," and microscopic evaluation in gynecologic pathology.

DATA SOURCES

This update is based on a review of recent peer-reviewed literature and the experience with cases at the parent institutions.

CONCLUSIONS

Gynecologic specimens received from patients with certain genetic conditions require specific clinicopathologic knowledge for appropriate pathologic examination. The evaluation of prophylactic resection specimens focuses on the detection of cancer precursors and possible occult disease, which may require a more thorough and detailed examination than an obvious carcinoma. Standardized protocols for handling prophylactic gynecologic resection specimens are available for some, but not all, types of specimens. The prospective evaluation of a gynecologic pathology specimen for potential genetic conditions such as microsatellite instability is a very recent subject. Currently, well-established protocols are not available; however, as clinical and prognostic significance has become more clearly elucidated, familiarity with this evolving field is increasingly important to properly assess these pathologic specimens.

Current and emerging trends in Lynch syndrome identification in women with endometrial cancer

OBJECTIVE

Lynch syndrome is a heritable, cancer susceptibility syndrome. This study aims to review current and emerging trends in the identification of Lynch syndrome in the endometrial cancer patient population.

METHODS

We performed a comprehensive review of past and present screening algorithms for Lynch syndrome, including a review of the utility of both the Amsterdam criteria and Bethesda guidelines. Because non-colon cancers have historically not been the focus of Lynch syndrome research, current literature is ripe with questions regarding screening among this patient population. Low BMI, age less than 50, positive family history and pathologic features have all been identified as risk factors in endometrial cancer patients who might benefit from Lynch screening. Additionally, based on experience at our own institution we offer a feasible screening algorithm for these patients.

RESULTS

A comprehensive review of the data demonstrated that immunohistochemistry is becoming an efficient, inexpensive way to screen tumors at risk for mismatch repair deficiency. The sensitivity and specificity of immunohistochemistry for predicting Lynch syndrome approaches 100%. Ideally, prospective screening of all endometrial cancer patients with IHC is a feasible, cost-efficient way to detect Lynch in this patient population given the limitations of using personal/family history of malignancy as well as pathologic risk factors.

CONCLUSION

It is imperative that clinicians be mindful of the risk of Lynch syndrome in women with endometrial cancer. Given the opportunity for colon cancer screening and prevention strategies to be initiated, the identification of probands with endometrial cancer as a result of Lynch syndrome will lead to a reduction in morbidity and mortality for these patients and their families.

Towards identification of hereditary DNA mismatch repair deficiency: sebaceous neoplasm warrants routine immunohistochemical screening regardless of patient's age or other clinical characteristics

Although the significance of immunohistochemical detection of DNA mismatch repair proteins and/or microsatellite instability testing in identifying patients at risk for germline deficiency in DNA mismatch repair genes is well established in colorectal carcinomas, the proper use of such techniques in sebaceous neoplasms, another tumor type that has been implicated in patients with hereditary DNA mismatch repair deficiency, has not been clearly defined. In this study, we stratified a series of 27 patients with 1 or more sebaceous neoplasms based on the pattern of immunohistochemical expression of MLH1, MSH2, MSH6, and PMS2, and comparatively analyzed their clinical and pathologic characteristics, including tumor-infiltrating lymphocytes and peritumoral lymphocytic response as determined by immunohistochemical staining for CD3. The study tissue samples included 30 sebaceous carcinomas, 14 sebaceous adenomas, and 7 sebaceous hyperplasias, along with 8 concurrent nonsebaceous lesions from 6 patients. Overall, 12 of the 27 (44%) patients showed abnormal IHC staining with mismatch repair proteins in their sebaceous tumors, the most commonly seen abnormality being concurrent loss of MSH2 and MSH6 (8/12, 67%). Sebaceous adenomas and carcinomas occurring in the same patients showed an identical staining pattern, as did hereditary nonpolyposis colorectal cancer-related nonsebaceous tumors in the same patients. When compared with cases that had normal expression of the mismatch repair proteins, cases with abnormal expression tended to be younger (median age, 56.5 y vs. 68 y), more likely to involve sites outside the head and neck (9/12 vs. 0/15), and more likely to have synchronous or metachronous visceral malignancies (8/12 vs. 3/15) and a positive family history. Furthermore, sebaceous tumors with abnormal expression had significantly higher CD3-positive tumor-infiltrating lymphocytes and peritumoral lymphocytic response. Thus, all these factors (age less than 60 y, involvement of nonhead and neck sites, visceral malignancy, family history fulfilling at least Bethesda guidelines, and lymphocytic infiltration) bore informative value in predicting abnormal expression of DNA mismatch repair proteins. However, their sensitivity was only modest, being 58%, 75%, 67%, 78%, and 75%, respectively. On such a premise, given that sebaceous neoplasms are only infrequently encountered, and that immunohistochemistry is easily available and reasonably reliable, we recommend that, when there exists a desire to identify hereditary DNA mismatch repair deficiency, routine immunohistochemical detection of DNA mismatch repair proteins be performed in all sebaceous neoplasms regardless of patient's age or other clinical characteristics.