ROLE OF INCISURA ANGULARIS BIOPSY IN GASTRITIS STAGING AND RISK ASSESSMENT OF GASTRIC CÂNCER.

BACKGROUND: Gastric atrophy (GA) and intestinal metaplasia (IM) are early stages in the development of gastric cancer. Evaluations are based on the Updated Sydney System, which includes a biopsy of the incisura angularis (IA), and the Operative Link on Gastritis Assessment (OLGA) and Operative Link on Gastritis Assessment using Intestinal Metaplasia (OLGIM) gastric cancer risk staging systems. OBJECTIVE: To compare the OLGA and OLGIM classifications with and without IA biopsy. In addition, to determine the prevalence of Helicobacter pylori (HP) and pre-neoplastic changes (GA and IM) in different biopsied regions and to identify the exclusive findings of IA. METHODS: Observational, prospective, descriptive, unicentric study with 350 patients without a diagnosis of gastric cancer, who underwent upper digestive endoscopy with biopsies at Gastroclínica Itajaí, from March 2020 to May 2022. The histopathological classification of gastritis followed the Updated Sydney System, and the gastric cancer risk assessment followed the OLGA and OLGIM systems. The methodology applied evaluated the scores of the OLGA and OLGIM systems with and without the assessment of the IA biopsy. Statistical analysis was performed using descriptive measures (frequencies, percentages, mean, standard deviation, 95% confidence interval). Ranks were compared using the Kruskal-Wallis or Wilcoxon tests. To analyze the relationship between the frequencies, the bilateral Fisher's exact test was used. Wilson's score with continuity correction was applied to the confidence interval. RESULTS: The median age was 54.7 years, with 52.57% female and 47.43% male patients. The comparison between the used biopsies protocol (corpus + antrum [CA] vs corpus + antrum + incisura angularis [CAI]) and the OLGA and OLGIM stages showed a significant decrease in both staging systems when the biopsy protocol restricted to the corpus and antrum was applied (OLGA CAI vs CA; P=0.008 / OLGIM CAI vs CA; P=0.002). The prevalence of pre-malignant lesions (GA, IM and dysplasia) of the gastric mucosa was (33.4%, 34% and 1.1%, respectively) in the total sample. The antrum region exhibited significantly higher numbers of alteration (P<0.001), except for HP infection, which was present in 24.8% of the patients. CONCLUSION: Incisura angularis biopsy is important because it increased the number of cases diagnosed in more advanced stages of intestinal metaplasia and atrophy. The study had limitations, with the main one being the relatively small sample size, consisting mostly of healthy individuals, although mostly elderly.

Papel da biópsia da incisura angular no estadiamento da gastrite e na avaliação de risco do câncer gástrico / Role of incisura angularis biopsy in gastritis staging and risk assessment of gastric câncer

ABSTRACT Background: Gastric atrophy (GA) and intestinal metaplasia (IM) are early stages in the development of gastric cancer. Evaluations are based on the Updated Sydney System, which includes a biopsy of the incisura angularis (IA), and the Operative Link on Gastritis Assessment (OLGA) and Operative Link on Gastritis Assessment using Intestinal Metaplasia (OLGIM) gastric cancer risk staging systems. Objective: To compare the OLGA and OLGIM classifications with and without IA biopsy. In addition, to determine the prevalence of Helicobacter pylori (HP) and pre-neoplastic changes (GA and IM) in different biopsied regions and to identify the exclusive findings of IA. Methods: Observational, prospective, descriptive, unicentric study with 350 patients without a diagnosis of gastric cancer, who underwent upper digestive endoscopy with biopsies at Gastroclínica Itajaí, from March 2020 to May 2022. The histopathological classification of gastritis followed the Updated Sydney System, and the gastric cancer risk assessment followed the OLGA and OLGIM systems. The methodology applied evaluated the scores of the OLGA and OLGIM systems with and without the assessment of the IA biopsy. Statistical analysis was performed using descriptive measures (frequencies, percentages, mean, standard deviation, 95% confidence interval). Ranks were compared using the Kruskal-Wallis or Wilcoxon tests. To analyze the relationship between the frequencies, the bilateral Fisher's exact test was used. Wilson's score with continuity correction was applied to the confidence interval. Results: The median age was 54.7 years, with 52.57% female and 47.43% male patients. The comparison between the used biopsies protocol (corpus + antrum [CA] vs corpus + antrum + incisura angularis [CAI]) and the OLGA and OLGIM stages showed a significant decrease in both staging systems when the biopsy protocol restricted to the corpus and antrum was applied (OLGA CAI vs CA; P=0.008 / OLGIM CAI vs CA; P=0.002). The prevalence of pre-malignant lesions (GA, IM and dysplasia) of the gastric mucosa was (33.4%, 34% and 1.1%, respectively) in the total sample. The antrum region exhibited significantly higher numbers of alteration (P<0.001), except for HP infection, which was present in 24.8% of the patients. Conclusion: Incisura angularis biopsy is important because it increased the number of cases diagnosed in more advanced stages of intestinal metaplasia and atrophy. The study had limitations, with the main one being the relatively small sample size, consisting mostly of healthy individuals, although mostly elderly.

RESUMO Contexto: A atrofia gástrica (AG) e a metaplasia intestinal (MI) são estágios iniciais do desenvolvimento do câncer gástrico. As avaliações são baseadas no Sistema de Sydney Atualizado, que inclui uma biópsia da incisura angular (IA), e nos sistemas de estadiamento de risco de câncer gástrico Operative Link on Gastritis Assessment (OLGA) e Operative Link on Gastritis Assessment using Intestinal Metaplasia (OLGIM). Objetivo: Comparar as classificações OLGA e OLGIM com e sem biópsia da IA. Além disso, determinar a prevalência de Helicobacter pylori (HP) e alterações pré-neoplásicas (AG e MI) em diferentes regiões biopsiadas e identificar os achados exclusivos da IA. Métodos: Estudo observacional, prospectivo, descritivo, unicêntrico, com 350 pacientes sem diagnóstico de câncer gástrico, submetidos à endoscopia digestiva alta com biópsias na Gastroclínica Itajaí, no período de março de 2020 a maio de 2022. A classificação histopatológica da gastrite seguiu o Sistema de Sydney Atualizado, e a avaliação do risco de câncer gástrico seguiu os sistemas OLGA e OLGIM. A metodologia aplicada avaliou os escores dos sistemas OLGA e OLGIM com e sem a avaliação da biópsia da IA. A análise estatística foi realizada por meio de medidas descritivas (frequências, porcentagens, média, desvio padrão, intervalo de confiança de 95%). As classificações foram comparadas usando os testes de Kruskal-Wallis ou Wilcoxon. Para analisar a relação entre as frequências, foi usado o teste exato de Fisher bilateral. O escore de Wilson com correção de continuidade foi aplicado ao intervalo de confiança. Resultados: A idade média foi de 54.7 anos, com 52.57% de pacientes do sexo feminino e 47.43% do sexo masculino. A comparação entre o protocolo de biópsias utilizado (corpo + antro [CA] vs corpo + antro + incisura angular [CAI]) e os estágios OLGA e OLGIM mostrou uma diminuição significativa em ambos os sistemas de estadiamento quando o protocolo de biópsia restrito ao corpo e ao antro foi aplicado (OLGA CAI vs CA; P=0.008 / OLGIM CAI vs CA; P=0.002). A prevalência de lesões pré-malignas (GA, MI e displasia) da mucosa gástrica foi de (33.4%, 34% e 1.1%, respectivamente) na amostra total. A região do antro exibiu um número significativamente maior de alterações (P<0.001), com exceção da infecção por HP, que estava presente em 24.8% dos pacientes. Conclusão: A biópsia de IA é importante porque aumentou o número de casos diagnosticados em estágios mais avançados de MI e AG. O estudo teve limitações, sendo a principal delas o tamanho relativamente pequeno da amostra, composta principalmente por indivíduos saudáveis, embora em sua maioria idosos.

Prevalence and clinical implications of germline pathogenic variants in cancer predisposing genes in young patients across sarcoma subtypes.

BACKGROUND: Sarcomas are a rare and diverse group of cancers occurring mainly in young individuals for which an underlying germline genetic cause remains unclear in most cases. METHODS: Germline DNA from 177 children, adolescents and young adults with soft tissue or bone sarcomas was tested using multigene panels with 113 or 126 cancer predisposing genes (CPGs) to describe the prevalence of germline pathogenic/likely pathogenic variants (GPVs). Subsequent testing of a subset of tumours for loss of heterozygosity (LOH) evaluation was performed to investigate the clinical and molecular significance of these variants. RESULTS: GPVs were detected in 21.5% (38/177) of the patients (15.8% in children and 21.6% in adolescents and young adults), with dominant CPGs being altered in 15.2% overall. These variants were found in genes previously associated with the risk of developing sarcomas (TP53, RB1, NF1, EXT1/2) but also in genes where that risk is still emerging/limited (ERCC2, TSC2 and BRCA2) or unknown (PALB2, RAD50, FANCM and others). The detection rates of GPVs varied from 0% to 33% across sarcoma subtypes and GPV carriers were more likely to present more than one primary tumour than non-carriers (21.1%×6.5%; p=0.012). Loss of the wild-type allele was detected in 48% of tumours from GPV carriers, mostly in genes definitively associated with sarcoma risk. CONCLUSION: Our findings reveal that a high proportion of young patients with sarcomas presented a GPV in a CPG, underscoring the urgency of establishing appropriate genetic screening strategies for these individuals and their families.

SURVIVAL OF PATIENTS WITH COLORECTAL CANCER IN A CANCER CENTER.

BACKGROUND: Hospital-based studies recently have shown increases in colorectal cancer survival, and better survival for women, young people, and patients diagnosed at an early disease stage. OBJECTIVE: To describe the overall survival and analyze the prognostic factors of patients treated for colorectal cancer at an oncology center. METHODS: The analysis included patients diagnosed with colon and rectal adenocarcinoma between 2000 and 2013 and identified in the Hospital Cancer Registry at A.C.Camargo Cancer Center. Overall 5-year survival was estimated using the Kaplan-Meier method, and prognostic factors were evaluated in a Cox regression model. Hazard ratios (HR) are reported with 95% confidence intervals (CI). RESULTS: Of 2,279 colorectal cancer cases analyzed, 58.4% were in the colon. The 5-year overall survival rate for colorectal cancer patients was 63.5% (65.6% and 60.6% for colonic and rectal malignancies, respectively). The risk of death was elevated for patients in the 50-74-year (HR=1.24, 95%CI =1.02-1.51) and ≥75-year (HR=3.02, 95%CI =2.42-3.78) age groups, for patients with rectal cancer (HR=1.37, 95%CI =1.11-1.69) and for those whose treatment was started >60 days after diagnosis (HR=1.22, 95%CI =1.04-1.43). The risk decreased for patients diagnosed in recent time periods (2005-2009 HR=0.76, 95%CI =0.63-0.91; 2010-2013 HR=0.69, 95%CI =0.57-0.83). CONCLUSION: Better survival of patients with colorectal cancer improves with early stage and started treatment within 60 days of diagnosis. Age over 70 years old was an independent factor predictive of a poor prognosis. The overall survival increased to all patients treated in the period 2000-2004 to 2010-2013.

Sobrevida de pacientes com câncer colorretal em um Cancer Center / Survival of patients with colorectal cancer in a cancer center

ABSTRACT BACKGROUND: Hospital-based studies recently have shown increases in colorectal cancer survival, and better survival for women, young people, and patients diagnosed at an early disease stage. OBJECTIVE: To describe the overall survival and analyze the prognostic factors of patients treated for colorectal cancer at an oncology center. METHODS: The analysis included patients diagnosed with colon and rectal adenocarcinoma between 2000 and 2013 and identified in the Hospital Cancer Registry at A.C.Camargo Cancer Center. Overall 5-year survival was estimated using the Kaplan-Meier method, and prognostic factors were evaluated in a Cox regression model. Hazard ratios (HR) are reported with 95% confidence intervals (CI). RESULTS: Of 2,279 colorectal cancer cases analyzed, 58.4% were in the colon. The 5-year overall survival rate for colorectal cancer patients was 63.5% (65.6% and 60.6% for colonic and rectal malignancies, respectively). The risk of death was elevated for patients in the 50-74-year (HR=1.24, 95%CI =1.02-1.51) and ≥75-year (HR=3.02, 95%CI =2.42-3.78) age groups, for patients with rectal cancer (HR=1.37, 95%CI =1.11-1.69) and for those whose treatment was started >60 days after diagnosis (HR=1.22, 95%CI =1.04-1.43). The risk decreased for patients diagnosed in recent time periods (2005-2009 HR=0.76, 95%CI =0.63-0.91; 2010-2013 HR=0.69, 95%CI =0.57-0.83). CONCLUSION: Better survival of patients with colorectal cancer improves with early stage and started treatment within 60 days of diagnosis. Age over 70 years old was an independent factor predictive of a poor prognosis. The overall survival increased to all patients treated in the period 2000-2004 to 2010-2013.

RESUMO CONTEXTO: Estudos hospitalares recentes têm demonstrado aumento da sobrevida do câncer colorretal e melhor sobrevida para mulheres, jovens e pacientes diagnosticados em estágio precoce da doença. OBJETIVO: Descrever a sobrevida global e analisar os fatores prognósticos de pacientes tratados para câncer colorretal em um centro de oncologia. MÉTODOS: Foram incluídos pacientes com diagnóstico de adenocarcinoma de cólon e reto entre 2000 e 2013, identificados no Registro Hospitalar de Câncer do A.C.Camargo Cancer Center. A sobrevida global aos 5 anos foi estimada pelo método de Kaplan-Meier e os fatores prognósticos foram avaliados pelo modelo de Cox. As razões de risco (HR) são relatadas com intervalos de confiança (IC) de 95%. RESULTADOS: Dos 2.279 casos de câncer colorretal analisados, 58,4% eram de cólon. A taxa de sobrevida global aos 5 anos para pacientes com câncer colorretal foi de 63,5% (65,6% e 60,6% para câncer de cólon e retal, respectivamente). O risco de óbito foi elevado para pacientes na faixa etária de 50-74 anos (HR=1,24; IC95% =1,02-1,51) e ≥75 anos (HR=3,02; IC95% =2,42-3,78), para pacientes com câncer retal (HR=1,37; IC95% =1,11-1,69) e para aqueles cujo tratamento foi iniciado >60 dias após o diagnóstico (HR=1,22; IC95% =1,04-1,43). O risco diminuiu para pacientes diagnosticados em períodos recentes (2005-2009 HR=0,76; IC95% =0,63-0,91; 2010-2013 HR=0,69; IC95% =0,57-0,83). CONCLUSÃO: A sobrevida dos pacientes com câncer colorretal é maior naqueles em estágio inicial e com início do tratamento antes dos 60 dias.. Idade acima de 70 anos foi fator independente preditivo de mau prognóstico. A sobrevida global aumentou para todos os pacientes tratados no período de 2000-2004 a 2010-2013.

Development of patient-derived orthotopic xenografts from metastatic colorectal cancer in nude mice.

Liver metastasis is the major cause of death for patients with colorectal cancer. Despite treatment with surgery and chemotherapy, patient outcomes are quite unfavourable. Thus, there is an urgent need to develop new treatment strategies with the associated establishment of good animal models. Metastatic disease can be modelled using patient-derived orthotopic xenografts, which accurately replicate intra-tumoral heterogeneity so that various chemotherapeutic agents can be tested on individual tumours to aid in clinical decision-making. The objective of this study was to develop metastatic colorectal tumours in athymic nude mice by implanting fresh tumour fragments into mouse liver parenchyma. Metastatic tumours were successfully propagated in mice following transplantation from human patients, then serially implanted in second and third-generation mice. Morphologic and immunohistochemical characteristics indicate that xenografts recreate the tumour architecture and mismatch repair gene expression for MLH1, MSH2, MSH1, and PMS2. After tumour implantation during the first passage, the time of tumour growth decreased without loss of tumour identity. Post-transplantation lymphoproliferative disease was observed in one case. This pilot study was successful in establishing the institutional PDX preclinical platform to study new therapeutic strategies, disease progression biomarkers, and treatment responsiveness.

Gastrointestinal stromal tumors treated at a Brazilian Cancer Center: evaluation of clinical, epidemiological, and therapeutic profiles

Background: Gastrointestinal stromal tumors (GISTs) originate as precursor cells of the interstitial cells of Cajal in the myenteric plexus and generally have a mutation in the tyrosine kinase receptor, C-KIT (CD117). The objective is to evaluate the clinical, epidemiological, and therapeutic profiles of GIST cases available from a hospital specializing in cancer treatment. Methods: A retrospective, longitudinal study of 85 GIST cases in a Cancer Center (São Paulo, Brazil) was conducted. Results: The cases identified involved 40 men and 45 women and the average age at diagnosis was 55.7 ± 14. 8 years (median, 57). The symptoms present at diagnosis depended on the location and dimensions of each lesion. In 49 cases (57.6%), the tumors had a gastric location and the mean dimensions were 7.2 ± 2.3 cm (median, 3.4 cm). Recurrent metastatic disease presented in 27 cases (with the liver mainly affected). Locoregional recurrence was detected in 16 cases. C-KIT was positive in 79/81 (97.5%) of the cases examined. Most of the tumors were initially treated with surgery, while clinical treatment was applied to the recurrent cases. The overall survival rate was 76.4% 162 months after diagnosis. Conclusions: The GISTs examined most commonly originated in the stomach, while the liver was the main site affected by metastatic lesions. Most of the lesions appeared to be slow-growing neoplasms that were positive for C-KIT (CD117). Complications, as well as death, mostly affected the elderly patients that had comorbidities or more aggressive forms of the disease (AU)

A genomic case study of desmoplastic small round cell tumor: comprehensive analysis reveals insights into potential therapeutic targets and development of a monitoring tool for a rare and aggressive disease.

BACKGROUND: Genome-wide profiling of rare tumors is crucial for improvement of diagnosis, treatment, and, consequently, achieving better outcomes. Desmoplastic small round cell tumor (DSRCT) is a rare type of sarcoma arising from mesenchymal cells of abdominal peritoneum that usually develops in male adolescents and young adults. A specific translocation, t(11;22)(p13;q12), resulting in EWS and WT1 gene fusion is the only recurrent molecular hallmark and no other genetic factor has been associated to this aggressive tumor. Here, we present a comprehensive genomic profiling of one DSRCT affecting a 26-year-old male, who achieved an excellent outcome. METHODS: We investigated somatic and germline variants through whole-exome sequencing using a family based approach and, by array CGH, we explored the occurrence of genomic imbalances. Additionally, we performed mate-paired whole-genome sequencing for defining the specific breakpoint of the EWS-WT1 translocation, allowing us to develop a personalized tumor marker for monitoring the patient by liquid biopsy. RESULTS: We identified genetic variants leading to protein alterations including 12 somatic and 14 germline events (11 germline compound heterozygous mutations and 3 rare homozygous polymorphisms) affecting genes predominantly involved in mesenchymal cell differentiation pathways. Regarding copy number alterations (CNA) few events were detected, mainly restricted to gains in chromosomes 5 and 18 and losses at 11p, 13q, and 22q. The deletions at 11p and 22q indicated the presence of the classic translocation, t(11;22)(p13;q12). In addition, the mapping of the specific genomic breakpoint of the EWS-WT1 gene fusion allowed the design of a personalized biomarker for assessing circulating tumor DNA (ctDNA) in plasma during patient follow-up. This biomarker has been used in four post-treatment blood samples, 3 years after surgery, and no trace of EWS-WT1 gene fusion was detected, in accordance with imaging tests showing no evidence of disease and with the good general health status of the patient. CONCLUSIONS: Overall, our findings revealed genes with potential to be associated with risk assessment and tumorigenesis of this rare type of sarcoma. Additionally, we established a liquid biopsy approach for monitoring patient follow-up based on genomic information that can be similarly adopted for patients diagnosed with a rare tumor.

BRAZILIAN CONSENSUS FOR MULTIMODAL TREATMENT OF COLORECTAL LIVER METASTASES. MODULE 3: CONTROVERSIES AND UNRESECTABLE METASTASES.

In the last module of this consensus, controversial topics were discussed. Management of the disease after progression during first line chemotherapy was the first discussion. Next, the benefits of liver resection in the presence of extra-hepatic disease were debated, as soon as, the best sequence of treatment. Conversion chemotherapy in the presence of unresectable liver disease was also discussed in this module. Lastly, the approach to the unresectable disease was also discussed, focusing in the best chemotherapy regimens and hole of chemo-embolization.

Neste último módulo do consenso, abordou-se alguns temas controversos. O primeiro tópico discutido foi o manejo da doença após progressão na primeira linha de quimioterapia, com foco em se ainda haveria indicação cirúrgica neste cenário. A seguir, o painel debruçou-se sobre as situações de ressecção da doença hepática na presença de doença extra-hepática, assim como, qual a melhor sequência de tratamento. O tratamento de conversão para doença inicialmente irressecável também foi abordado neste módulo, incluindo as importantes definições de quando se pode esperar que a doença se torne ressecável e quais esquemas terapêuticos seriam mais efetivos à luz dos conhecimentos atuais sobre a biologia tumoral e taxas de resposta objetiva. Por último, o tratamento da doença não passível de ressecção foi discutida, focando-se nos melhores esquemas a serem empregados e seu sequenciamento, bem como o papel da quimioembolização no manejo destes pacientes.

Brazilian consensus for multimodal treatment of colorectal liver metastases. module 3: controversies and unresectable metastases / Consenso brasileiro de tratamento multidisciplinar de metástase hepática de origem colorretal módulo 3: controvérsias e metástases irressecáveis

ABSTRACT In the last module of this consensus, controversial topics were discussed. Management of the disease after progression during first line chemotherapy was the first discussion. Next, the benefits of liver resection in the presence of extra-hepatic disease were debated, as soon as, the best sequence of treatment. Conversion chemotherapy in the presence of unresectable liver disease was also discussed in this module. Lastly, the approach to the unresectable disease was also discussed, focusing in the best chemotherapy regimens and hole of chemo-embolization.

RESUMO Neste último módulo do consenso, abordou-se alguns temas controversos. O primeiro tópico discutido foi o manejo da doença após progressão na primeira linha de quimioterapia, com foco em se ainda haveria indicação cirúrgica neste cenário. A seguir, o painel debruçou-se sobre as situações de ressecção da doença hepática na presença de doença extra-hepática, assim como, qual a melhor sequência de tratamento. O tratamento de conversão para doença inicialmente irressecável também foi abordado neste módulo, incluindo as importantes definições de quando se pode esperar que a doença se torne ressecável e quais esquemas terapêuticos seriam mais efetivos à luz dos conhecimentos atuais sobre a biologia tumoral e taxas de resposta objetiva. Por último, o tratamento da doença não passível de ressecção foi discutida, focando-se nos melhores esquemas a serem empregados e seu sequenciamento, bem como o papel da quimioembolização no manejo destes pacientes.

Análise de CD10, BCL-6 e MUM1 em linfomas não Hodgkin de células B primários de mediastino / Analysis of CD10, BCL-6 and MUM1 im primary mediastinal large B cell lymphomas

INTRODUÇÃO: Os linfomas B atualmente podem ser agrupados de acordo semelhanças moleculares e imunoistoquímicas com o linfócito do centro germinativo (CG) ou linfócito ativado (LA/pós CG), sendo este de pior prognóstico. O objetivo deste trabalho foi analisar a expressão de CD10, BCL-6 e MUM1 em pacientes portadores de LBPM e correlacionar com prognóstico. MÉTODOS: análise retrospectiva das variáveis clínicas e de tratamento de 44 pacientes portadores de LBPM. Estudo imunoistoquímico de CD10, BCL-6 e MUM1 em 29 pacientes com material disponível. RESULTADOS: idade mediana foi de 28 anos e 70% eram do sexo feminino. A positividade para CD10, BCL-6 e MUM1 foi de: 24%, 65% e 58%. De acordo com o modelo de Hans, 38% foi classificado como CG e 62% como pós CG. A sobrevida global em 5 anos e sobrevida livre de doença foi de 47% e 81%, respectivamente. Resposta Completa após quimioterapia de primeira linha (p=0,0001), radioterapia de mediastino (p=0,004) e IPI (0,039) tiveram associação com a sobrevida. A positividade para MUM1 esteve associado a pior sobrevida global (p=0,014). Aplicando o modelo de Hans não foi observada nenhuma associação com sobrevida. Na análise multivariada apenas Resposta (RR 4,28 (IC 95% 1,3-13,6) e MUM1 (RR 3,54 (1,1-11,5) correlacionaram com a sobrevida. CONCLUSÃO: Para este grupo de pacientes com características clínicas homogêneas, resposta completa e expressão de MUM1 estiveram associados à sobrevida. A classificação deste linfoma em CG e pós-CG utilizando CD10, BCL-6 e MUM1 não se correlacionou com evolução. Estudos futuros com casuística maior são necessários para melhor definir os fatores prognósticos do LBPM.

INTRODUCTION: Primary Mediastinal Large B Cell Lymphoma (PMLBCL) is a distinct clinico-pathologic entity that differs from other Diffuse Large B Cell Lymphomas (DLBCL). Classification of DLBCL in GC and post-GC according can identify two subgroups of lymphomas with distinct prognosis. The aim of this study is to analyze the expression of CD10, BCL-6 and MUM1 in PMLBCL and correlate with prognosis. METHODS: retrospective analysis of clinical variables of 44 patients with PMLBCL and expression of CD10, BCL- 6 and MUM1 in 29 patients with available tissue. RESULTS: median age was 28 years and 70% of the patients were female. CD10, BCL-6 and MUM1 was positive in 24%, 65% and 58%, respectively. According to Hans classification, 38% were classified as GC and 62% as post-GC. Five year OS and DFS was 47% and 81%, respectively. In univariate analysis Complete Response (p=0.0001), Radiation therapy (p=0.004), IPI (0.039), and MUM1 expression (0.014) correlated with OS. No correlation was seen with Hans classification and survival. CONCLUSION: for this group of patients with homogeneous clinical features, response to therapy and MUM1 expression were associated with prognosis. The Hans algorithm proposed for aggressive lymphomas was not a predictive tool for survival in PMLBCL. Further studies are necessary to validate our finding and identify better prognostic variable for PMLBCL.