Progress of Lynch syndrome associated endometrial cancer / 肿瘤研究与临床

Lynch syndrome (LS) is a common hereditary tumor syndrome. Gynecological malignancy is usually the first tumor of LS in women, and endometrial cancer (EC) is the most closely associated with LS. Most patients with LS are unaware of this risk, and it is possible to cause misdiagnosis. Thus, early diagnosis helps patients to start tumor surveillance timely, as well as a cascade of family surveillance. This paper reviews the progress of LS associated with EC.

Clinical characteristics of elderly patients with Lynch syndrome-associated endometrial cancer and analysis of MSH2 gene variation in their families / 中华老年医学杂志

Objective:To study the clinical characteristics of Lynch syndrome-associated endometrial cancer in elderly patients and the relationship of the disease with MSH2 gene mutations in patients' families.Methods:Clinical data of 473 elderly patients with endometrial cancer admitted to our hospital between January 2016 and January 2021 were retrospectively analyzed.MSH2 gene mutations were detected and verified by DNA sequence analysis, real-time quantitative PCR and reverse transcription PCR.Patients were divided into a Lynch syndrome group and a non-Lynch syndrome group, and the clinicopathological features of the two groups were compared.Results:Of 473 endometrial carcinoma patients, 46(9.7%)had embryogenic mutations of the MMR gene and were diagnosed with Lynch syndrome, with 18, 6, 24 and 10 patients carrying MLH1, PMS2, MSH2 and MSH6 mutations, respectively.There were 3 mutations in the MSH2 gene, including exon 7 1380C>A, exon 12 2011A>G and exon 13 2756A→AC.The proportions of patients with G3 grade endometrioid adenocarcinoma, lower uterine segment involvement and a history of Lynch syndrome-associated malignant tumors in the Lynch syndrome group were significantly higher than those in the non-Lynch syndrome group( χ2=8.935, 8.303, 9.770, all P<0.05). Conclusions:Poorly differentiated endometrioid adenocarcinoma, predisposition to lower uterine segment involvement and familial inheritance are the main clinical manifestations of Lynch syndrome-associated endometrial carcinoma in elderly patients, with the most common mutations seen in the MSH2 gene.

Efficacy of B-Lynch compression suture for control of intractable hemorrhage during cesarean section

Background: Primary postpartum hemorrhage (PPH) due to atonicity during lower segment cesarean section is commonly seen in obstetric practice. Usually, it responds to uterotonics but at times it may lead to life-threatening complications. B-Lynch brace suture is a fertility-preserving alternative surgical technique used in patients with primary atonic PPH not responding to uterotonics. This study was conducted to find out the efficacy of B-Lynch sutures in the surgical management of atonic PPH and prevention of obstetric hysterectomy in the same patients. Materials and Methods: The study included 34 patients with primary atonic PPH during cesarean section refractory to oxytocics and managed with B-Lynch brace sutures. It was a cross-sectional observational study conducted over 1 year at a tertiary hospital. The amount of blood loss, any additional surgical procedure required, and associated complications were studied in these patients. Results: Fertility could be preserved in 100% of the patients undergoing B-Lynch sutures for primary atonic PPH, following the failure of the medical line of management. No major complications including uterine wall necrosis or pyometra were observed in any of these patients. Conclusion: B-Lynch suture is a safe, effective, simple, life-saving, and fertility-preserving surgical technique in the treatment of primary PPH that requires lesser expertise. So it can easily be used before major interventions such as uterine devascularization or obstetric hysterectomy.

Lynch syndrome: An unusal case of familial cancer unearthed

Lynch syndrome or hereditary nonpolyposis colorectal cancer (HNPCC) is a type of inherited cancer syndrome with a genetic predisposition to different types of cancer. There is an increased predisposition to cancers in the endometrium, colon, stomach, ovary, uterus, skin, kidney, and brain in patients of Lynch syndrome. We are reporting a 48-year-old male who presented with a pea-sized growth in his left arm which was found to be sebaceoma on histopathology. On further detailed history, examination, and genetic study, it was proved to be a familial case of Lynch syndrome. The case is being reported to stress the importance of knowledge about clinical manifestation, associated neoplasms, and molecular genetic profile of Lynch syndrome which will enable physicians and pathologists to provide highly targeted surveillance and management for patients with high cancer risk.

Evaluation of microsatellite instability in routine examinations of surgical samples

Context: Approximately 20%–30% of colon cancer cases have a hereditary basis. The genetic defect may involve mismatch repair (MMR) genes, which results in microsatellite instability (MSI). MMR-deficient colorectal cancer may occur due to germline mutation (Lynch syndrome) or be a sporadic one. A tumor's histological features, supported by a panel of immunohistochemistry stains, enables pathologists to assess the MMR status, which in turn has beneficial effects on clinical management. Aims: We aimed to show the relations between histopathological features identified during routine examinations and MMR genes' mutations. Methods and Material: We reviewed retrospectively the material of the Department of Pathology fulfilling the revised Bethesda Guidelines. Statistical Analysis Used: We used Chi-square test, Spearman test, and epidemiological analysis. Results: For the PMS2 gene, the positive predictive value (PPV) indicates that 91% of cases neither present any histological lesions nor have genetic abnormalities. The negative predictive value (NPV) indicates that only 50% of cases have both histological and genetic changes. For the MSH6 gene, the PPV indicates that 85% of tumors without specific histological features do not have genetic abnormalities. Conclusions: We advise universal staining for MLH1, MSH2, MSH6, and PMS2 in every newly diagnosed colon cancer, but due to costly analyses we suggest a protocol for the selection of cases for MMR examinations.

Caracterização clínica, molecular e genética de pacientes com câncer colorretal abaixo de 50 anos / Clinical, molecular and genetic characterization of colorectal cancer patients under 50 years of age

Introdução: Pacientes com câncer colorretal (CCR) em idade jovem (< 50 anos) apresentam maior risco de apresentar variantes germinativas em genes de predisposição ao câncer, entre eles os genes da Síndrome de Lynch (SL) (genes MMR - MLH1, MSH2, MSH6 e PMS2). Detectar a perda de expressão de proteínas de reparo de incompatibilidade de DNA (MMR) é altamente relevante para identificar pacientes com síndrome de Lynch. No entanto, a inativação de MLH1 devido à hipermetilação do promotor ocorre em 15% dos cânceres colorretais (CCRs) esporádicos e está correlacionada com mutações somáticas BRAF. Ainda, apesar das principais síndromes hereditárias de CCR representarem 15-19% dos casos de CCR de início precoce, a etiologia da maior parte dos CCRs nestes pacientes é desconhecida, mesmo com até 25% destes casos apresentando história familiar importante para essa neoplasia. Objetivo: Caracterizar o fenótipo clínico e molecular (somático e germinativo) de pacientes com CCR desenvolvido antes dos 50 anos tratados no A.C.Camargo Cancer Center. Materiais e Métodos: Pacientes com câncer colorretal <50 anos foram selecionados a partir do banco de dados do Departamento de Cirurgia Pélvica ou pelo encaminhamento do Departamento de Oncogenética. A análise de metilação do promotor de MLH1 foi realizada por sequenciamento de nova geração (NGS) a partir de DNA convertido por bissulfito de sódio, em uma metodologia desenvolvida e validada nesse estudo. A análise de mutação de BRAF foi realizada por NGS de amplicon. Para um subgrupo de pacientes com critérios clínicos e moleculares específicos (tumores MMR deficientes, história familiar positiva para CCR, mutação KRAS: G12C e/ou idade <40 anos) foi realizado o sequenciamento germinativo de genes de predisposição ao CCR. Na avaliação das variantes germinativas foi utilizado um painel multigênico com 62 genes de associação conhecida, emergente ou desconhecida para predisposição ao CCR. As variantes identificadas foram classificadas segundo os critérios sugeridos pelo American College of Medical Genetics (ACMG). Resultados: Para análise de metilação de MLH1 utilizamos DNA de tumores FFPE e saliva foi tratado com bissulfito, amplificado por PCR e avaliado por NGS. Em tumores deficientes em MLH1/PMS2, o estado de metilação de MLH1 foi concordante com o estado de mutação BRAF em 90% (18/20) dos casos. Nosso teste NGS baseado em amplicon mostrou uma grande sensibilidade e especificidade para detectar a metilação de MLH1 em amostras de CCR, com alta concordância com a avaliação da mutação BRAF. A avaliação das variantes germinativas foi realizada em 89 pacientes, e identificamos 24 (27%) pacientes com variantes patogênicas ou provavelmente patogênicas (P/PP). A maioria dos pacientes 53% (47/89) apresentaram variantes de significado incerto (VUS) e 18 (20%) pacientes apresentaram apenas variantes sem significado clínico para os 62 genes avaliados. Dos 24 pacientes com variantes patogênicas, 16 (66,6%) apresentaram variantes P/PP em genes da síndrome de Lynch. Cinco pacientes (20%) apresentaram variantes P/PP em MUTYH (3 bialélicos e 2 monoalélicos). Dois (8,3%) pacientes tinham variantes PP em FAN1. Um paciente apresentou uma variante PP em NTHL1 (monoalélica), e para os genes XRCC4 e RAD51C tivemos um paciente cada com alteração. Dois pacientes apresentaram variantes P/PP em mais de 1 gene (1 MLH1 com FAN1, 1 MUTYH com XRCC4). Conclusão: Em nosso trabalho fomos capazes de desenvolver com sucesso uma metodologia baseada em NGS para avaliação de metilação no promotor do gene MLH1, para caracterizar molecularmente as amostras tumorais do grupo de pacientes com deficiência nos genes de reparo relacionados a causas esporádicas (metilação de MLH1 e mutação de BRAF). Além disso, identificamos variantes germinativas com evidência definitiva de predisposição ao CCR em 1 a cada 4 pacientes da nossa coorte, além de termos identificado variantes patogênicas em genes com evidência limitada ou ausente de predisposição hereditária ao câncer CCR, como é o caso dos genes RAD51C, XRCC4 e FAN1.

Introduction: Patients with colorectal cancer (CRC) at a young age (< 50 years) are at greater risk of having germline variants in cancer predisposition genes, including Lynch Syndrome (LS) genes (MMR genes - MLH1, MSH2, MSH6 and PMS2). Detecting the loss of expression of DNA mismatch repair (MMR) proteins is highly relevant to identify patients with Lynch syndrome. However, inactivation of MLH1 due to promoter hypermethylation occurs in 15% of sporadic colorectal cancers (CRCs) and is correlated with somatic BRAF mutations. Also, although the main hereditary syndromes of CRC represent 15-19% of cases of early-onset CRC, the etiology of most CRCs in these patients is unknown, even with up to 25% of these cases presenting an important family history of this neoplasm. Objective: To characterize the clinical and molecular phenotype (somatic and germline) of patients with CRC developed before the age of 50 years treated at the A.C.Camargo Cancer Center. Materials and Methods: Colorectal cancer patients <50 years were selected from the database of the Department of Pelvic Surgery or by referral from the Department of Oncogenetics. MLH1 promoter methylation analysis was performed by next-generation sequencing (NGS) from DNA converted by sodium bisulfite, in a methodology developed and validated in this study. BRAF mutation analysis was performed by amplicon NGS. For a subgroup of patients with specific clinical and molecular criteria (MMR deficient tumors, positive family history for CCR, KRAS:G12C mutation, and/or age <40 years) germline sequencing of CRC predisposing genes was performed. In the evaluation of germline variants, a multigene panel with 62 genes of known, emerging or unknown association for CRC predisposition was used. The identified variants were classified according to the criteria suggested by the American College of Medical Genetics (ACMG). Results: For MLH1 methylation analysis we used DNA from FFPE tumors and saliva was treated with bisulfite, amplified by PCR and evaluated by NGS. In MLH1/PMS2 deficient tumors, MLH1 methylation status was concordant with BRAF mutation status in 90% (18/20) of cases. Our amplicon-based NGS test showed great sensitivity and specificity for detecting MLH1 methylation in CRC samples, with high agreement with the BRAF mutation assessment. The evaluation of germline variants was performed in 89 patients, and we identified 24 (27%) patients with pathogenic or probably pathogenic (P/PP) variants. Most patients 53% (47/89) had variants of uncertain significance (VUS) and 18 (20%) patients had only variants without clinical significance for the 62 genes evaluated. Of the 24 patients with pathogenic variants, 16 (66.6%) had P/PP variants in Lynch syndrome genes. Five patients (20%) had P/PP variants in MUTYH (3 biallelic and 2 monoallelic). Two (8.3%) patients had PP variants in FAN1. One patient had a PP variant in NTHL1 (monoallelic), and for the XRCC4 and RAD51C genes we had one patient each with alteration. Two patients had P/PP variants in more than 1 gene (1 MLH1 with FAN1, 1 MUTYH with XRCC4). Conclusion: In our work, we were able to successfully develop a methodology based on NGS for the evaluation of methylation in the promoter of the MLH1 gene, to molecularly characterize the tumor samples from the group of patients with deficiency in the repair genes related to sporadic causes (MLH1 methylation and BRAF mutation). In addition, we identified germline variants with definitive evidence of predisposition to CRC in 1 out of 4 patients in our cohort, in addition to having identified pathogenic variants in genes with limited or no evidence of hereditary predisposition to CRC cancer, such as the RAD51C genes, XRCC4 and FAN1.

Current management status of hereditary colorectal cancer / 中华胃肠外科杂志

Hereditary colorectal cancer accounts for approximately 5% of all colorectal cancer cases, mainly including familial adenomatous polyposis and Lynch syndrome. Total proctocolectomy plus ileal pouch-anal anastomosis and total colectomy plus ileorectal anastomosis are two major procedures for familial adenomatous polyposis, however, the exact impact of these two procedures on surgical efficacy, oncologic efficacy as well as functional results still remains uncertain. Segmental colectomy and total colectomy are two major procedures for Lynch syndrome, each of them both has advantages and disadvantages, and there still lacks a consensus about the optimal strategy because of the nature of retrospective study with a relatively insufficient evidence support. As a result, we would make a review about the current surgical treatment status and future perspectives of hereditary colorectal cancer.

Diagnosis and treatment of familial colorectal cancer type X / 中华消化外科杂志

About 1/3 of patients with colorectal cancer have a genetic background. Familial colorectal cancer type X refers to colorectal cancer clinically in line with Amsterdam criteria Ⅱ, but genetic testing of which does not show microsatellite instability or DNA mismatch repair gene mutations. Its tumor cell gene is microsatellite stable. Attention should be paid to the differen-tiation from Lynch syndrome. Familial colorectal cancer type X is highly heterogeneous, without unclear etiology so far. It is recommended to refer to sporadic colorectal cancer for diagnosis, treatment, follow-up and prevention. The authors introduce the diagnosis and treatment of a case of familial colorectal cancer type X, in order to provide references for clinical diagnosis of this disease.

Progress of Lynch-like syndrome / 肿瘤研究与临床

The functional loss of the mismatch repair system is related to the occurrence of colorectal cancer. Some colorectal cancers have mismatch repair defects, however, the methylation of the MLH1 promoter cannot be detected, and germline mutations of the mismatch repair genes are not detected. Because this part of the group is very similar to Lynch syndrome, it is named Lynch-like syndrome. Lynch-like syndrome has certain genetic characteristics, but the pathogenesis has not been fully understood; and it cannot be simply classified as sporadic colorectal cancer or Lynch syndrome, and there is a lack of genetic knowledge and monitoring standards of these patients. This article introduces the progress of Lynch-like syndrome.

Narrative review comparing the epidemiology, characteristics, and survival in sporadic colorectal carcinoma/Lynch syndrome / Revisão narrativa na comparação da epidemiologia, características e sobrevivência no Carcinoma Colorretal esporádico/Síndrome de Lynch

Abstract Introduction: Colorectal carcinoma is the third most prevalent neoplasm in the world, and the second cause of death by cancer. The most part of these neoplasms are sporadic by somatic mutations, but around 15% are hereditary, such as Lynch syndrome or hereditary nonpolyposis colorectal cancer (HNPCC). Despite being the same tumor, it has differences between these two contexts as well as different prognosis. In Lynch syndrome cases, the survival of these individuals was greater than that observed in sporadic cases. Methods: This review focuses on the different characteristics and development of colorectal carcinoma in sporadic and Lynch syndrome cases, in order to conclude what may motivate the greater survival in the tumors associated with this syndrome. Results: Although the histopathological features drive into a worse prognosis, the colorectal carcinoma in the Lynch Syndrome presents a greater survival comparing to sporadic colorectal carcinoma. Discussion: The greater survival in the colorectal carcinoma in the HNPCC compared to the sporadic carcinomas has been linked to factors such as high microsatellite instability, diploid predominance, earlier screening for colo-rectal carcinoma, deficient DNA repair mechanism, low p53 mutation rate, and presence of lymphoid aggregates involving the neoplasm. Conclusion: Further studies should be conducted to provide new insights about survival of colorectal carcinoma in Lynch syndrome, as well as the therapeutic alternatives for this neoplasia.

Resumo Introdução: O carcinoma colorretal é a terceira neoplasia mais prevalente no mundo, bem como a segunda causa de morte por câncer. A maioria destas neoplasias são esporádicas, devidas a mutações somáticas, mas cerca de 15% são hereditárias como a síndrome de Lynch ou Hereditary Nonpolyposis Colorectal Cancer (HNPCC). Apesar de ser a mesma neoplasia, esta apresenta características clinico-patológicas e moleculares distintas, bem como diferentes prognósticos. Nos casos de síndrome de Lynch, a sobrevida parece ser maior quando comparada com os carcinomas esporádicos. Métodos: Realizamos uma revisão bibliográfica sobre as diferentes características e desenvolvimentos do carcinoma colorretal esporádico e no contexto da síndrome de Lynch, para concluir o que causa a maior sobrevida no caso das neoplasias associadas a esta síndrome. Resultados: Apesar das características histopatológicas apontarem para um pior prognóstico, o HNPCC apresenta uma maior sobrevida em relação ao carcinoma colorretal esporádico. Discussão: A maior sobrevivência nos carcinomas colorretais associados ao HNPCC em comparação com os carcinomas colorretais esporádicos tem sido atribuída a fatores como a elevada instabilidade microssatélite, a predominância diploide, a realização de rastreio para o carcinoma colorretal mais precoce, deficiente mecanismo de reparação de DNA, menor taxa de mutação da p53 e existência de agregados linfoides a envolver a neoplasia. Conclusão: Consideramos que deve ser encorajado o estudo mais aprofundado dos fatores que levam à maior sobrevida do carcinoma colorretal na síndrome de Lynch, bem como de alternativas terapêuticas para esta neoplasia.

Extensive colectomy in colorectal cancer and hereditary nonpolyposis colorectal cancer - long-term results / Colectomia extensa em cancro colorretal e cancro colorretal hereditário sem polipose - resultados a longo prazo

ABSTRACT Background: Colorectal cancer survival is better in hereditary nonpolyposis colorectal cancer patients than in sporadic colorectal cancer patients and even for hereditary nonpolyposis colorectal cancer with colorectal cancer is not consensual that extensive colectomy is preferable to partial colectomy. This study analyzes and compares the long-term results of these two groups of patients submitted to curative subtotal colectomy or total colectomy. Methods: Between 2002 and 2018, 68 patients with colorectal cancer without familial adenomatous polyposis were submitted to a total or subtotal colectomy in a single tertiary center. The patients were divided in two groups: hereditary nonpolyposis colorectal cancer patients (with Amsterdam criteria) and sporadic colorectal cancer patients (the others). The presence of Amsterdam criteria for hereditary nonpolyposis colorectal cancer and germline mutation for mismatch repair genes was confirmed by clinical records. Results and survival were analyzed following surgery. Results: We obtained a sporadic colorectal cancer group with 31 patients and a hereditary nonpolyposis colorectal cancer group with 37 patients. The two groups differ in age but not in gender, tumor stage or surgical morbidity. The overall survival and disease-free survival were good in both groups but even better for hereditary nonpolyposis colorectal cancer group with statistical significance when comparing the two groups. Conclusion: Total or subtotal colectomy for colorectal cancer provides a good survival. These surgical procedures should be considered the first option for colorectal cancer in young hereditary non polyposis colorectal cancer patients. In those cases, they provide good long-term results, avoiding the risk of metachronous colorectal cancer and the surveillance is restricted only to the remaining need for rectum.

RESUMO Introdução: A sobrevivência do cancro colorretal é melhor em pacientes com cancro colorretal hereditário não associado a polipose do que em pacientes com cancro colorretal esporádico. Mesmo em casos de cancro colorretal hereditário sem polipose, a preferência pela colectomia total em relação à parcial não é consensual na literatura. Este estudo analisa e compara os resultados a longo prazo destes dois grupos de pacientes submetidos à colectomia curativa subtotal ou total. Métodos: Entre 2002 e 2018, 68 pacientes com cancro colorretal sem polipose adenomatosa familiar foram submetidos a colectomia total ou subtotal em um único centro terciário. Os pacientes foram divididos em dois grupos: aqueles com cancro colorretal hereditário sem polipose (de acordo com os critérios de Amsterdão) e os com cancro colorretal esporádico (os demais). Os critérios de Amsterdão para cancro colorretal hereditário sem polipose e a presença de mutação germinativa para os genes de reparação de ADN foram confirmados por consulta dos registros clínicos. Os resultados e a sobrevivência foram analisados após a cirurgia. Resultados: No presente estudo, 31 pacientes foram incluídos no grupo de cancro colorretal esporádico e 37 no grupo de cancro colorretal hereditário sem polipose. Diferenças significativas foram observadas em relação à idade, mas não ao gênero, estadio do tumor ou morbilidade cirúrgica. A sobrevivência global e a sobrevivência livre de doença foram boas em ambos os grupos, mas os resultados foram ainda melhores no grupo de cancro colorretal hereditário sem polipose, com significado estatístico. Conclusão: A colectomia total ou a colectomia subtotal para o cancro colorretal proporcionam uma boa sobrevivência e devem ser consideradas a primeira opção de tratamento em pacientes jovens com cancro colorretal hereditário sem polipose. Nestes pacientes, uma cirurgia cólica mais extensa permite a obtenção de bons resultados a longo prazo; reduz o risco de cancro colorretal metácrono e restringe a vigilância endoscópica ao reto remanescente.

B-lynch suture in the management of uterine atony during caesarean section section

Background: Third stage of labour is still the “sword of Damocle’s” hanging above an obstetrician , inspite  of  today’s advanced technologies and personal care .The importance in the management of this deadly stage lies in the anticipation of complications and being quick enough to treat them timely.  Hence in such scenarios, B-lynch suture is most popular method in treatment of uterine atony during caesarean section. The objective is to study and evaluate the cases in which the B-Lynch suture was used to treat the uterine atony during caesarean section.Methods: A prospective randomized study consisting of 50 women with high risk factors for atonic pph during caesarean section were included as study group patients were subjected to B-Lynch suture application when conventional drugs failed to control PPH. Blood loss was measured using a measuring jar. The fall in Hb% and the need for blood transfusion, and the need for hysterectomy as a last resort to save the life was evaluated.Results: The average blood loss was 1490 ml and the majority of patients had reduction in Hb% from 1.1-1.5 gm% (52%), 36% of the patients did not receive any blood transfusion after B-Lynch suture, and in 80% of cases hysterectomy was avoided.Conclusions: Our study shows cases treated with B-Lynch procedure showed that it is an effective method of containing pph.  It has the advantage of being applied easily and safely. It should be attempted when conservative management fails and before any radical surgery is considered.

Desenlaces con dos técnicas de sutura hemostática uterina en pacientes con hemorragia obstétrica / Results with two techniques of uterine hemostatic sutures in obstetric hemorrhage patients

Resumen OBJETIVO: Exponer los desenlaces de dos técnicas de sutura hemostática uterina para controlar la hemorragia obstétrica. MATERIALES Y MÉTODOS: Estudio prospectivo, observacional y longitudinal, llevado a cabo en tres unidades hospitalarias de Guanajuato, México, del 1 de enero al 30 de noviembre de 2018. Se incluyeron pacientes con hemorragia transcesárea y posparto. En las primeras se aplicó la técnica de B-Lynch y en las segundas la de Hayman. Se analizaron las variables: 1) cantidad de hemorragia antes y después de aplicar la sutura, 2) tiempo del procedimiento, 3) concentración de hemoglobina al ingreso a la unidad de atención, 1 hora después de la hemorragia y 24 horas posteriores a la intervención quirúrgica, 4) desenlace de las técnicas y 5) complicaciones. Para el análisis de los datos se utilizó el programa SPSS versión 22 para Windows. RESULTADOS: Se registraron 34 pacientes: 26 con aplicación de la técnica de sutura B-Lynch y 8 con la técnica de Hayman. La pérdida sanguínea después de la aplicación de las técnicas fue menor (p < 0.001). El tiempo entre el diagnóstico de hemorragia y la aplicación de la sutura fue de 11.5 ± 5.9 minutos. La concentración de hemoglobina al ingreso al hospital y 1 h posterior a la hemorragia fue significativamente menor (p < 0.01) versus 24 h después (p < 0.05) 30 de 34 pacientes tuvieron reacción favorable al tratamiento quirúrgico. Cuatro mujeres requirieron procedimientos adicionales para el control de la hemorragia. No se reportaron complicaciones ni muertes maternas asociadas con las técnicas de sutura. CONCLUSIONES: Las técnicas de sutura uterina representan un procedimiento útil, rápido y sin complicaciones para el control de la hemorragia obstétrica.

Abstract OBJECTIVE: To present the results obtained with two techniques of uterine hemostatic sutures for the control of obstetric hemorrhage. MATERIALS AND METHODS: Prospective, observational, longitudinal study in three hospital units of the 1st. from January to November 30, 2018. Thirty-four patients with postpartum and transcesarean hemorrhage were included. The postpartum patients underwent Hayman technique and the B-Lynch technique. The following were analyzed: 1) amount of hemorrhage before and after the sutures, 2) time between diagnosis and placement, 3) hemoglobin levels at admission to the care unit, 1 hour after the hemorrhage and 24 hours after treatment, 4) results with the two techniques and 5) complications. Statistical analysis of all these variables was performed with SPSS, 22 version. RESULTS: A total of 34 patients were registered: 26 sutures performed with B-Lynch technique and 8 with Hayman technique. The amount of bleeding after the application was lower (p <0.001). The time between diagnosis of bleeding and placement was 11.5 + 5.9 minutes. The hemoglobin levels at admission to the hospital and one hour after the hemorrhage were significantly lower (p <0.01) and 24 hours later (p <0.05). In 30/34 of cases, a favorable response to surgical treatment was achieved. In four cases, another procedure was required to control bleeding. There were no complications with the use of sutures or maternal deaths. CONCLUSIONS: The use of uterine sutures was a useful, fast and uncomplicated therapy for the control of obstetric hemorrhage.

A frameshift mutation in exon 19 of MLH1 in a Chinese Lynch syndrome family: a pedigree study / 浙江大学学报（英文版）（B辑：生物医学和生物技术）

Lynch syndrome (LS), an autosomal dominantly inherited disease previously known as hereditary non-polyposis colorectal cancer (HNPCC), leads to a high risk of colorectal cancer (CRC) as well as malignancy at certain sites including endometrium, ovary, stomach, and small bowel (Hampel et al., 2008; Lynch et al., 2009). Clinically, LS is considered the most common hereditary CRC-predisposing syndrome, accounting for about 3% of all CRC cases (Popat et al., 2005). LS is associated with mutations of DNA mismatch repair (MMR) genes such as MLH1, MSH2, MSH6, PMS2, and EPCAM (Ligtenberg et al., 2009; Lynch et al., 2009), which can trigger a high frequency of replication errors in both microsatellite regions and repetitive sequences in the coding regions of various cancer-related genes. Immunohistochemistry (IHC) tests followed by genetic analysis of these mutations play a significant role in diagnosis, treatment determination, and therapeutic response prediction of LS (Lynch et al., 2009; Alex et al., 2017; Ryan et al., 2017). Here, we report substitution of one base-pair in exon 1 of MLH3 (c.1397C>A) and a frameshift mutation in exon 19 of MLH1 (c.2250_2251ins AA) in a 43-year-old Chinese male with an LS pedigree.

Comprehensive application of various screening strategies of Lynch syndrome / 中华胃肠外科杂志

Lynch syndrome (LS), which is the most common hereditary colorectal cancer, accounts for about 3% of all colorectal cancers. However, due to its various clinical manifestations, it is difficult to be diagnosed. The diagnosis of LS requires comprehensive application of various screening criteria (such as the Amsterdam criteria, Bethesda criteria), predictive models, risk factors, immunohistochemistry test of mismatch repair (MMR) protein, microsatellite instability (MSI) detection, MLH1 methylation detection, BRAF gene mutation detection, germline gene mutation detection, and so on. LS can be diagnosed only after the identification of pathogenic germline mutation of MMR gene. The first-degree and second-degree relatives of LS patients are recommended to be tested for the identified mutant gene. For LS patients and gene mutation carriers, LS associated cancer can be detected early or even prevented by monitoring and preventive surgery. Reproductive techniques can be used to prevent this disease from being passed down to the next generation.

Síndrome de Lynch: aspectos genéticos, clínicos y diagnósticos / Lynch syndrome: genetic, clinical and diagnostic aspects

Esta revisión tiene como objetivo dar a conocer los aspectos genéticos, clínicos y diagnósticos del síndrome de Lynch, además de brindar la información más relevante acerca de la asesoría genética en estos pacientes y las recomendaciones actuales para su seguimiento.

This review aims to present the genetic, clinical and diagnostic aspects of Lynch syndrome, as well as providing the most relevant information about genetic counseling in these patients and the current recommendations for their surveillance.

Síndrome de Lynch: impacto de la caracterización de familias en base a estudios genéticos / Lynch syndrome: impact of the characterization of families based on genetic studies

El objetivo de este trabajo fue caracterizar demográfica y molecularmente las familias con diagnóstico de síndrome de Lynch en base a estudios genéticos. Se utilizó la base prospectiva del Registro de Epidemiología Molecular de Cáncer Colorrectal (REM-CCR) del Hospital Italiano de Buenos Aires (Clinical trials.gov NCT02781337). El criterio de inclusión fue que tuvieran hecho un estudio genético entre 1996 y 2017 (secuenciación y/o determinación de grandes rearreglos de al menos un gen reparador de error de apareamiento). Se analizaron 50 familias con los criterios de Amsterdam. En 23 (46%) se identificaron variantes patogénicas (n=19) y probablemente patogénicas (n=2). El 28.6% de las variantes patogénicas fueron originalmente descritas en esta serie, entre ellas la variante c.1911del en el exón 12 de MSH2 identificada en una familia con agregación de cáncer de mama. Fue identificada una mutación fundadora de Piamonte, Italia (c.2252_2253del). Los genes afectados incluyeron MSH2 (13 variantes) MLH1 (9 variantes) y PMS2 (1 variante). La tasa de detección de mutaciones fue del 46%. Entre las familias con mutación identificada (n=23), se detectó una edad mediana de inicio del cáncer menor (46 vs. 50 años, p=0.02) y mayor incidencia de tumores extra-colorrectales (90.5% vs. 45.8%, p <0.01), que las 27 sin mutaciones. La implementación de estudios genéticos permitió caracterizar variables demográficas en base a la identificación de mutaciones germinales asociadas al síndrome de Lynch, identificándose dos grupos diferenciados por la edad de afectación y la incidencia de tumores extracolónicos (AU)

The aim of this study was to characterize demographically and molecularly families diagnosed with Lynch syndrome based on genetic studies. Families with a genetic study performed between 1996 and 2017 (sequencing and/or determination of large rearrangements of a mismatch repair gene at least) were selected from the prospective database REM-CCR of Hospital Italiano de Buenos Aires (Clinical trials. Gov NCT02781337). Fifty families fulfilled Amsterdam criteria were analyzed. Pathogenic variants were found in 23 out of 50 (46%) families, being 21 pathogenic and 2 likely pathogenic. The 28.6% of the pathogenic variants were originally described in this series. Among them, the variant c.1911del in MSH2 in a family with breast cancer aggregation and a founder MLH1 mutation from Piedmont, Italy (c.2252_2253del) were identified. Affected genes include MSH2 (13 variants), MLH1 (9 variants), PMS2 (1 variant). Mutations detection rates was 46%. Those families with an identified mutation (n=23) had a lower median age of cancer onset (46 vs. 50 years, p=0.02) and a higher incidence of extra-colorectal tumors (90.5% vs. 45.8%, p<0.01) than those without identified mutations (n=27). The implementation of genetic studies allowed characterizing demographic variables based on the identification of germline mutations associated with Lynch syndrome. Two groups, Síndrome de Lynch: impacto de la caracterización de familias en base a estudios genéticos 3 differentiated by the age of cancer onset and the incidence of extracolonic tumors were characterized (AU)

Expression and clinical significance of mismatch repair gene in colorectal cancer / 中国肿瘤临床

Objective: To investigate the expression and clinical significance of mismatch repair genes (MMR) MLH1, MSH2, MSH6, and PMS2 in colorectal carcinoma. Methods: Colorectal cancer tissues, collected from 607 patients enrolled in Sichuan Provincial People's Hospital from January 2015 to September 2016, were assigned into two groups based on whether the samples were positive or nega-tive for MMR expression to determine the relationship between MMR expression and clinicopathology. We then evaluated the diag-nostic value of MMR expression in the screening of Lynch syndrome and sporadic colorectal cancer. Results: The deletion rate of MMR protein was 35.58%. No statistically significant difference in age, sex, tumor size, P53, CD34, and D2-40 expression was detected be-tween the negative group with MMR protein deficiency and the positive group with normal expression (P>0.05). Differences in tumor location, differentiation, TNM stage, lymph node metastasis, and VEGF and Ki-67 expression between the two groups were statistically significant (P<0.05). The combined detection of MLH1, MSH2, PSM2, and MSH6 proteins may serve as a simple and economical meth-od for screening patients with Lynch syndrome. Conclusions: The risk of colorectal cancer can be reduced by MMR detection of surgi-cal specimens from colorectal cancer patients, screening of patients with Lynch syndrome and their family members, and assisting with proper management and intervention.

Consensus on clinical diagnosis, treatment and pedigree management of hereditary colorectal cancer in China / 中华肿瘤杂志

Hereditary colorectal cancer can be divded into two categories based on the presence or absence of polyps. The first category is characterized by the development of polyposis, which includes familial adenomatous polyposis (FAP); The second category is nonpolyposis colorectal cancer, which is represented by Lynch syndrome. "Consensus on clinical diagnosis, treatment and pedigree management of hereditary colorectal cancer in China" developed by the Genetics Group of the Committee of Colorectal Cancer, Chinese Anti-cancer Association, is composed of three sections, including hereditary nonpolyposis syndrome, polyposis syndrome as well as genetic evaluation of hereditary colorectal cancer. The consensus aims to provide recommendations on management of the respective hereditary syndromes in terms of definition, clinical and pathological features, diagnostic standards, treatment, and follow-ups. In addition to describing diagnostic and treatment strategies, prophylactic treatment as well as genetic screening and pedigree monitoring is highly recommended. Through the establishment of this expert consensus, we hope to promote better understanding of hereditary colorectal cancer for clinicians and encourage standardized treatment through multidisciplinery approaches, eventually improving clinical treatment and pedigree management of hereditary colorectal cancer in China.

Consensus on clinical diagnosis, treatment and pedigree management of hereditary colorectal cancer in China / 中华肿瘤杂志

Hereditary colorectal cancer can be divded into two categories based on the presence or absence of polyps. The first category is characterized by the development of polyposis, which includes familial adenomatous polyposis (FAP); The second category is nonpolyposis colorectal cancer, which is represented by Lynch syndrome. "Consensus on clinical diagnosis, treatment and pedigree management of hereditary colorectal cancer in China" developed by the Genetics Group of the Committee of Colorectal Cancer, Chinese Anti-cancer Association, is composed of three sections, including hereditary nonpolyposis syndrome, polyposis syndrome as well as genetic evaluation of hereditary colorectal cancer. The consensus aims to provide recommendations on management of the respective hereditary syndromes in terms of definition, clinical and pathological features, diagnostic standards, treatment, and follow-ups. In addition to describing diagnostic and treatment strategies, prophylactic treatment as well as genetic screening and pedigree monitoring is highly recommended. Through the establishment of this expert consensus, we hope to promote better understanding of hereditary colorectal cancer for clinicians and encourage standardized treatment through multidisciplinery approaches, eventually improving clinical treatment and pedigree management of hereditary colorectal cancer in China.