子宫内膜癌错配修复蛋白表达与临床病理特征的关系分析

目的探讨错配修复(mismatch repair, MMR)蛋白在子宫内膜癌组织中的表达及其与临床病理特征的关系。方法回顾性分析2013年1月至2018年1月在首都医科大学大兴教学医院行全子宫切除术并经病理诊断的81例子宫内膜癌患者的临床病理资料,采用免疫组织化学检测MSH2、MSH6、MLH1、PMS2表达,并分析其与患者预后指标的关系。结果 81例子宫内膜癌患者中,MMR蛋白总表达缺失率为14.8%(12/81),其中MLH1/PMS2配对表达缺失率最高(66.7%,8/12),MSH2/MSH6配对表达缺失次之(16.7%,2/12),MSH6或PMS2单独表达缺失最少(8.3%,1/12)。MMR表达缺失组与MMR表达正常组在脉管内癌栓、淋巴结转移、累及子宫下段、临床FIGO分期进行比较,差异均有统计学意义(P 0.05);而在患者年龄、肿瘤分化程度、组织学类型、浸润深度及有无复发比较,差异均无统计学意义(P0.05)。结论 MMR蛋白表达异常可辅助用于初步筛选子宫内膜癌相关Lynch综合征患者,并有助于子宫内膜癌的早期筛查和早期诊断。     

MMR蛋白在Lynch综合征相关子宫内膜癌初筛中的应用

目的:通过检测错配修复(MMR)蛋白在子宫内膜癌(EC)中的表达情况,探讨MMR蛋白在Lynch综合征相关EC中筛查的可行性。方法:收集2015年6月至2018年6月于青岛市市立医院行免疫组化法检测MMR蛋白(MLH1/MSH2/MSH6/PMS2)表达的EC患者80例,分析MMR蛋白表达缺失病例的临床资料及肿瘤组织病理学特点,其中2例行全外显子测序明确基因突变位点。结果:80例EC患者中,MMR蛋白表达缺失者22例(27.5%),其中以MLH1和PMS2蛋白缺失表达为主。MMR蛋白表达缺失者年龄相对更小,以子宫下段居多(P0.05)。其中2例经全外显子基因测序验证了相应MMR基因的突变。结论:免疫组化检测MMR蛋白表达缺失可用于Lynch综合征相关EC的初筛。MMR蛋白表达缺失与患者低龄及病灶部位相关。对于经济条件允许的患者,可进一步行全外显子测序确定相关基因的突变位点。     

子宫内膜癌组织错配修复基因MMR表达及其临床意义

目的:通过检测子宫内膜癌组织错配修复(MMR)蛋白表达缺失情况,探讨错配修复基因在子宫内膜癌中的临床意义。方法:回顾分析北京大学人民医院2018年5月至2019年7月收治的101例子宫内膜癌患者的完整临床病理资料。免疫组化法分析子宫内膜癌组织中MMR蛋白(MSH2、MSH6、MLH1、PMS2)及ER、PR、Ki67表达情况。结果:101例子宫内膜癌中MMR、MSH2、MSH6、MLH1、PMS2蛋白表达缺失率分别为40.6%(41/101)、8.9%(9/101)、10.9%(11/101)、14.9%(15/101)、31.7%(32/101)。MLHl/PSM2及MSH2/MSH6联合缺失率分别为13.9%(14/101)及4.0%(4/101)。BMI<24kg/m~2与MSH2表达缺失相关(P<0.05),24kg/m~2≤BMI<28kg/m~2与PMS2表达缺失相关(P<0.05);内科合并症(高血压病、糖尿病等)与MLH1表达缺失相关(8.2%vs 24.3%,P<0.05)。肌层浸润深度≥1/2与MMR、MSH6、MLH1及PMS2表达缺失相关(P<0.01)。肿瘤直径≥2cm与MMR及PMS2表达缺失相关(P<0.01)。结论:MMR蛋白表达缺失与预后不良相关。肿瘤组织MMR蛋白尤其是MLH1/PMS2检测有助于识别预后不良患者,特别是Lynch综合评估后进行辅助治疗,有助于改善预后。     

免疫组化检测子宫内膜癌中MMR蛋白的抗体组合优化

目的:比较MLH1、MSH2和PMS2、MSH6两种抗体组合在子宫内膜癌(EC)MMR蛋白表达缺失的敏感性,优化检测EC中MMR蛋白表达缺失的抗体组合。方法:选取126例EC肿瘤组织,应用免疫组化法检测EC中MLH1、MSH2、PMS2和MSH6蛋白的表达。结果:126例子宫内膜癌中MLH1和MSH2蛋白缺失的检出率为22.22%(28/126),PMS2和MSH6蛋白缺失的漏诊率为6.35%(8/126);PMS2和MSH6蛋白缺失的检出率为29.37%(37/126),MLH1和MSH2蛋白缺失的漏诊率为5.56%(7/126)。结论:应用MLH1、MSH2和PMS2、MSH6两种抗体组合均不能完全检测到MMR蛋白的表达缺失,仍需联合应用四种抗体检测EC中MMR蛋白的表达缺失,防止某一种MMR蛋白表达缺失病例的漏诊。     

Lynch综合征相关子宫内膜癌新进展

子宫内膜癌是女性Lynch综合征患者最常见的肠外肿瘤,与散发性子宫内膜癌不同,该病是常染色体显性遗传病,病因及发病机制是错配修复基因(MLH1、MSH2、MSH6及PMS2)的突变或异常表达。患者发病年龄年轻,病理类型多样,包括子宫内膜样癌、透明细胞癌、浆液性癌、未分化癌或癌肉瘤等。由于该病再次发生肿瘤的风险较高,危害大,因此及时治疗Lynch综合征相关的子宫内膜癌是有效预防该类患者再次发生肿瘤的关键。就Lynch综合征相关子宫内膜癌的病因、发病机制、临床病理特征及诊断、治疗和筛查新进展进行综述。     

曼彻斯特国际共识小组对Lynch综合征相关妇科癌症管理指南的解读

Lynch 综合征是一种常染色体显性遗传性癌症综合征,是由于 DNA 错配修复 (mismatch repair, MMR) 相关基因MLH1、MSH2、MSH6、PMS2的致病性突变所致,包括结直肠癌、子宫内膜癌及卵巢癌等[1-2].对Lynch综合征的诊断不仅可以为患者自身的治疗、随访及监测等提供有效的指导,而且可...     

MMR缺失型子宫内膜癌E-cadherin、N-cadherin表达与临床病理特征的相关性分析

目的:分析错配修复(MMR)蛋白缺失型子宫内膜癌患者临床病理特征与上皮型钙黏蛋白(E-cadherin)、神经型钙黏蛋白(N-cadherin)表达之间的相关性。方法:选择2016年1月至2018年6月在宁夏医科大学总医院手术治疗,术后病理确诊为子宫内膜癌伴MMR缺失即MMR(-)的子宫内膜癌患者40例,另选择同期MMR表达正常即MMR(+)的子宫内膜癌患者40例为对照组,E-cadherin、N-cadherin单克隆抗体行石蜡组织切片免疫组化染色,对比性分析其表达与临床病理特征的相关性。结果:MMR(-)型与MMR(+)型子宫内膜癌对比,在年龄、子宫肌层浸润深度、肿瘤累及子宫下段、阴道断端及宫旁软组织浸润、淋巴结转移中,差异无统计学意义(P 0.05),在病理类型、国际妇产科联盟(Federation of Obstetrics and Gynaecology,FIGO)分期、组织学分化程度和淋巴脉管浸润(lymph-vascular space invasion,LVSI)中,差异有统计学意义(P 0.05);MMR(-)型子宫内膜癌组织中,E-cadherin阳性率、总染色强度、阳性细胞数均低于MMR(+)型,而N-cadherin表达呈相反趋势,差异有统计学意义(P 0.01);MMR(-)型子宫内膜癌组织中,E-cadherin、N-cadherin表达呈负相关(r=-0.678,P 0.01)。结论:MMR(-)型子宫内膜癌与MMR(+)型子宫内膜癌组织E-cadherin/N-cadherin表达趋势不同,具有不同的上皮间质转化水平,可能导致临床病理特征差异的形成。     

p53和MMR联合检测在子宫内膜癌预后判断中的作用

目的:探讨错配修复(MMR)蛋白表达与p53表达联合检测在子宫内膜癌(EC)预后判断中的作用。方法:回顾分析95例EC患者的临床资料,收集蜡块进行p53和MMR (MLH1,PMS2,MSH2,MSH6)免疫组化。根据MMR及p53免疫组化结果将患者分为4组:MMR表达完整(MMR-p)/p53野生型表达(p53 wt),MMR-p/p53突变型(p53 abn),MMR缺失(MMR-d)/p53 wt,MMR-d/p53 abn。分析MMR、p53联合检测与患者总体生存率(OS)及各组间临床病理学特征的差异。结果:联合检测分组后可得到四条不同的生存曲线,结果有统计学意义(P0.01),其中MMR-d/p53 abn组预后最差,MMR-d/p53 wt组预后最好。四组的组织学类型和肿瘤分级比较,差异有统计学意义(P0.05)。结论:MMR和p53免疫组化检测在临床中操作简便,适用性强,为预后和治疗提供有用信息。     

MSH2基因13号外显子移码突变致Lynch综合征相关子宫内膜癌一例

子宫内膜癌是女性常见的恶性肿瘤之一,绝大部分子宫内膜癌为散发型,只有2%为遗传型,遗传型子宫内膜癌也称为Lynch综合征相关性子宫内膜癌(LS-EC)。本例患者43岁,因子宫下段赘生物活检提示子宫内膜低分化腺癌,行子宫内膜癌根治性手术,因肿瘤位于子宫下段,且病理特征提示子宫内膜样腺癌,因存在多个高危因素故行Lynch综合征筛查。根据2019年Manchester国际共识,妇科肿瘤筛查Lynch综合征的流程明确,首先采用免疫组化法检测丢失的蛋白,发现潜在的突变基因,最终通过高通量测序(NGS)技术确诊为MSH2基因13号外显子E701fs移码突变导致的LS-EC。     

“Lynch综合征相关妇科肿瘤监管的曼彻斯特国际共识”要点解读

正Lynch综合征(Lynch syndrome,LS)是一组常染色体显性遗传的癌症综合征,主要包括结直肠癌(colorectal cancer,CRC)、子宫内膜癌(endometrial cancer,EC)以及卵巢癌(ovarian cancer,OC)[1]。LS的发病根源是由于细胞DNA的错配修复(MMR)系统中的MLH1、MSH2、MSH6和PMS2的基因突变,其阻碍了细胞DNA合成过程中的错配修复[2]。早期及时诊断可以对癌症的预测及下一步治疗产生影响。目前,已证实LS患者进行CRC监管可以获得很好的生存获益[3],而国际上LS相关CRC监管的临床指南,并不完全适合妇科肿瘤。在女性中,LS的首发肿瘤多为EC,而且由于子宫内膜癌的前驱症状较明显,临床多早期发现,早     

Double somatic mismatch repair gene pathogenic variants as common as Lynch syndrome among endometrial cancer patients

ObjectiveLynch syndrome is the most common cause of inherited endometrial cancer, attributable to germline pathogenic variants (PV) in mismatch repair (MMR) genes. Tumor microsatellite instability (MSI-high) and MMR IHC abnormalities are characteristics of Lynch syndrome. Double somatic MMR gene PV also cause MSI-high endometrial cancers. The aim of this study was to determine the relative frequency of Lynch syndrome and double somatic MMR PV.Methods341 endometrial cancer patients enrolled in the Ohio Colorectal Cancer Prevention Initiative at The Ohio State University Comprehensive Cancer Center from 1/1/13–12/31/16. All tumors underwent immunohistochemical (IHC) staining for the four MMR proteins, MSI testing, and MLH1 methylation testing if the tumor was MMR-deficient (dMMR). Germline genetic testing for Lynch syndrome was undertaken for all cases with dMMR tumors lacking MLH1 methylation. Tumor sequencing followed if a germline MMR gene PV was not identified.ResultsTwenty-seven percent (91/341) of tumors were either MSI-high or had abnormal IHC indicating dMMR. As expected, most dMMR tumors had MLH1 methylation; (69, 75.8% of the dMMR cases; 20.2% of total). Among the 22 (6.5%) cases with dMMR not explained by methylation, 10 (2.9% of total) were found to have Lynch syndrome (6 MSH6, 3 MSH2, 1 PMS2). Double somatic MMR PV accounted for the remaining 12 dMMR cases (3.5% of total).ConclusionsSince double somatic MMR gene PV are as common as Lynch syndrome among endometrial cancer patients, paired tumor and germline testing for patients with non-methylated dMMR tumor may be the most efficient approach for LS screening.     

Mismatch repair protein deficiency in endometriosis: Precursor of endometriosis-associated ovarian cancer in women with lynch syndrome

ObjectiveWe aimed to elucidate the pathogenesis of ovarian cancer through the loss of mismatch repair (MMR) proteins in women with Lynch syndrome (LS) in this report.Case reportTwo women with LS underwent surgery for synchronous endometrial cancer and ovarian cancer. In both cases, immunohistochemical examination showed concomitant MMR protein deficiency in endometrial cancer, ovarian cancer, and contiguous ovarian endometriosis. In Case 1, the macroscopically normal ovary included multiple endometrioses with MSH2 and MSH6 expression, and FIGO grade 1 endometrioid carcinoma and contiguous endometriosis without MSH2 and MSH6 expression. In Case 2, all endometriotic cells contiguous with carcinoma in the lumen of the ovarian cyst showed loss of the expression of MSH2 and MSH6.ConclusionOvarian endometriosis with MMR protein deficiency may progress to endometriosis-associated ovarian cancer in women with LS. Diagnosing endometriosis in women with LS during surveillance is important.     

Lynch Syndrome in patients with clear cell and endometrioid cancers of the ovary

Objective

Patients with Lynch Syndrome are at an increased risk for a variety of malignancies, including ovarian cancer. Ovarian cancers associated with Lynch Syndrome are predominantly clear cell or endometrioid in histology. Lynch Syndrome is characterized by germline mutations in mismatch repair (MMR) genes. The current study aims to assess the prevalence of loss of MMR expression in patients with endometrioid and clear cell ovarian carcinoma.

Methods

A retrospective review identified 90 patients with endometrioid and/or clear cell carcinomas. Slides made from tumor tissue microarray blocks were evaluated using immunohistochemical stains with antibodies against MLH1, PMS2, MSH2, and MSH6. Statistical analysis was performed.

Results

Seven of the 90 cases (7.8%) had loss of MMR expression. The mean age of patients with loss of MMR expression (47 years) was significantly younger than those with retained MMR expression (p = 0.014). Loss of MMR expression was present in 20% of patients under the age of 53 with clear cell or endometrioid cancers. Genetic studies found that 3 of the 5 patients with loss of MMR expression carried mutations consistent with Lynch Syndrome; acquired hypermethylation of MLH1 was noted in one patient. Six of 7 patients (86%) whose tumors lacked MMR expression had synchronous or metachronous primary malignancies, a significantly greater prevalence than those with retained MMR expression (p < 0.001).

Conclusion

Patients under the age of 53 with clear cell or endometrioid ovarian carcinomas are at a clinically significant risk for loss of MMR expression and Lynch Syndrome; routine screening with immunohistochemical staining should be considered.     

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

OBJECTIVE: To estimate the frequency of mismatch repair deficiencies associated with hereditary nonpolyposis colorectal cancer, or Lynch syndrome, in women less than age 50 with endometrial cancer. METHODS: Consecutive patients less than age 50 diagnosed with endometrial adenocarcinoma were identified. Available pathologic specimens were freshly sliced, and protein expression for MLH1, MSH2, MSH6, and PMS2 was evaluated by immunohistochemistry. Slides were scored on a semiquantitative method with complete absence of any of the four proteins suggesting a deficiency. All results were confirmed by microsatellite instability testing. RESULTS: Sixty-one pathology specimens were analyzed. Twenty-one (34%) of the tumors had absence of staining of at least one of the four mismatch repair proteins determined by immunohistochemistry and confirmed by microsatellite instability testing. Obese patients were less likely than nonobese patients to have a mismatch repair deficiency (21% versus 59%, respectively). Non-obese patients had a relative risk for a mismatch repair deficiency of 5.5 (95% confidence interval 1.6-19.1; P=.01). CONCLUSION: Many women diagnosed with endometrial cancer before age 50 will have a mismatch repair deficiency discovered by immunohistochemistry and microsatellite instability testing. A number of young women diagnosed with endometrial cancer will require further genetic testing for mismatch repair mutations. LEVEL OF EVIDENCE: III.     

Evaluation of a nationwide Dutch guideline to detect Lynch syndrome in patients with endometrial cancer

ObjectiveIn the Netherlands a nationwide guideline was introduced in 2016, which recommended routine Lynch syndrome screening (LSS) for all women with endometrial cancer (EC) <70 years of age. LSS consists of immunohistochemical (IHC) staining for loss of mismatch repair (MMR) protein expression, supplemented with MLH1 methylation analysis if indicated. Test results are evaluated by the treating gynaecologist, who refers eligible patients to a clinical geneticist. We evaluated the implementation of this guideline.MethodsFrom the nation-wide pathology database we selected all women diagnosed with EC < 70 years of age, treated from 1.6.2016–1.6.2017 in 14 hospitals. We collected data on the results of LSS and follow up of cases with suspected LS.ResultsIn 183 out of 204 tumours (90%) LSS was performed. In 41 cases (22%) MMR protein expression was lost, in 25 cases due to hypermethylation of the MLH1 promotor. One patient was known with a pathogenic MLH1 variant. The option of genetic counselling was discussed with 12 of the 15 remaining patients, of whom three declined. After counselling by the genetic counsellor nine patients underwent germline testing. In two no pathogenic germline variant was detected, two were diagnosed with a pathogenic PMS2 variant, and five with a pathogenic MSH6 variant, in concordance with the IHC profiles.ConclusionCoverage of LSS was high (90%), though referral for genetic counselling could be improved. Gynaecologists ought to be aware of the benefits and possible drawbacks of knowing mutational status, and require training in discussing this with their patients.     

不同分子学筛查方法在Lynch综合征相关子宫内膜癌患者中的对比分析#br#

Objective?Compare the accuracy of immunohistochemical staining (IHC), microsatellite instability detection (MSI), and the combined detection of the two in the screening of Lynch Syndrome-related endometrial cancer (LS-EC), and analyze the advantages and disadvantages of actual clinical applications, to identify a routine and reasonable screening strategy. This study also reveals the incidence of LS-EC and the mutations of different mismatch repair (MMR) genes in the Chinese population in this region. Methods?IHC MMR protein detection and MSI detection were performed on the pathological tissues of diagnosed EC patients from the Second Hospital of Jilin University from November 2019 to November 2020, and the preoperative venous blood was subjected to next-generation sequencing (NGS) of Lynch syndrome-related mutations. Results?After NGS testing, 8 cases of LS were confirmed, with an incidence rate of 7.90%. 28 cases had lack of expression of MMR protein, 7 cases were diagnosed as LS, 1 case was missed diagnosis; 13 cases had high microsatellite instability (MSI-H), 3 cases were diagnosed as LS, 5 cases were missed; the combined detection of the two tests can screen out all LS patients. Conclusion?IHC combined with MSI screening is highly sensitive but not cost-effective. IHC alone is recommended as the first clinical screening method.     

Ovarian cancer linked to Lynch syndrome typically presents as early-onset, non-serous epithelial tumors

Objective

Heredity is a major cause of ovarian cancer and during recent years the contribution from germline mismatch repair (MMR) gene mutations linked to Lynch syndrome has gradually been recognized.

Methods

We characterized clinical features, tumor morphology and mismatch repair defects in all ovarian cancers identified in Swedish and Danish Lynch syndrome families.

Results

In total, 63 epithelial ovarian cancers developed at mean 48 (range 30-79) years of age with 47% being early stage (FIGO stage I). Histologically, endometrioid (35%) and clear cell (17%) tumors were overrepresented. The underlying MMR gene mutations in these families affected MSH2 in 49%, MSH6 in 33% and MLH1 in 17%. Immunohistochemical loss of the corresponding MMR protein was demonstrated in 33/36 (92%) tumors analyzed.

Conclusion

The combined data from our cohorts demonstrate that ovarian cancer associated with Lynch syndrome typically presents at young age as early-stage, non-serous tumors, which implicates that a family history of colorectal and endometrial cancer should be specifically considered in such cases.     

Nm23 expression in node-positive and node-negative endometrial cancer.

OBJECTIVE: To examine the relationships between the expression of protein Nm23 and surgical stage, histologic grade, histopathologic findings, and survival in women with endometrial carcinoma. METHODS: 19 patients with lymph node involvement were matched with 24 patients without lymph node involvement and the best paraffin-embedded blocks were selected for Nm23 immunohistochemical staining. The slides were evaluated semiquantitatively according to their degree of cytoplasmic staining. Statistical analysis was performed to determine whether there was a relationship between Nm23 expression and surgical stage, histologic grade, depth of myometrial invasion, lymph node metastasis, and/or lymphovascular space involvement. Survival analysis was also performed. RESULTS: Slides from 15 patients (79%) with lymph node involvement and 22 patients (88%) without lymph node involvement were found to be positive for Nm23 (P=0.01). No significant relations were observed between Nm23 expression and surgical stage, histologic grade, depth of myometrial invasion, or lymphovascular space involvement. Nm23 expression was found to be significantly related to lower rates of lymph node metastasis and longer survival (P=0.02). CONCLUSION: Elevated Nm23 expression is related to lower rates of lymph node metastasis and longer survival.     

Universal Testing to Identify Lynch Syndrome Among Women With Newly Diagnosed Endometrial Carcinoma

BackgroundLynch syndrome (LS) is an autosomal dominant cancer syndrome caused by a germline mutation in the mismatch repair (MMR) genes. Protocols based on immunohistochemical expression of MMR proteins in cancer are used to identify patients with LS.MethodsThe universal LS screening protocol of the Tom Baker Cancer Centre (Calgary, AB) of all patients diagnosed between April 1, 2013 and April 1, 2015 with endometrioid carcinoma of the endometrium was audited through a retrospective chart review. LS status and frequency of protocol compliance at each of the key steps were calculated (Canadian Task Force Classification II-2).ResultsThe cohort consisted of 375 patients. MMR immunohistochemical testing was requested for 321 (85.6%). Expression of at least one protein was lost in 86 (26.8%). Twenty-one (6.5%) patients were eligible for genetic counselling because PMS2, MSH2, or MSH6 protein expression was lost in 19, and two patients had a family history of LS. Eleven (91.7%) of 12 (57.1%) who attended had germline testing, and six (54.5%) showed a mutation diagnostic of LS. LS status among the cohort of 375 patients was positive in six (1.6%), negative in 294 (78.4%), and unknown in 75 (20%) because of protocol non-compliance. LS was confirmed in six (2%) of the 321 women who completed the protocol.ConclusionThis is the first audit of a Canadian-based universal LS screening protocol of patients with endometrial cancer. The success of the protocol is endorsed by the 80% compliance and by the 2% prevalence of LS, which is within the published range.