Endoscopic Approach to Duodenal Adenomas in Familial Adenomatous Polyposis: A Retrospective Cohort.

Introduction: Over 90% of the patients with familial adenomatous polyposis (FAP) will develop duodenal adenomas. Aim: The aim of this study was to evaluate the effectiveness and safety of endoscopic excision of large duodenal adenomas in FAP patients. Methods: All FAP patients from a familial risk clinic submitted to endoscopic therapy for duodenal adenomas ≥10 mm between January 2010 and February 2021 were included. Results: From 151 FAP families, 22 patients (50 lesions) were included: 54.5% female; median follow-up 8.5 (IQR: 5.8-12.3) years after the first endoscopy. First therapeutic endoscopy occurred at a median age of 41.0 years (IQR: 33.0-58.2). Repeat therapeutic endoscopy was required in 54.5% of patients. Median size of the largest adenoma was 15 mm (IQR: 10-18 mm); resection was piecemeal in 63.1% and en bloc in the remaining. In 2 cases, the resection was incomplete (fibrosis due to previous resection and difficult positioning). Complications occurred in 6.3% of the resected lesions (4 patients): 2 immediate (bleeding, perforation); 4 in the first week (1 bleeding, 2 mild pancreatitis, 1 perforation requiring surgery; the latter two after ampullectomy). Histology revealed low-grade dysplasia adenomas in 90.1%; no adenocarcinomas were found. One patient with Spigelman stage IV disease not amenable to endoscopic control underwent elective duodenopancreatectomy (without duodenal cancer). Conclusion: Endoscopic surveillance and treatment of duodenal adenomas in FAP patients was safe and effective in the prevention of duodenal cancer.

Introdução: Mais de 90% dos doentes com Polipose Adenomatosa Familiar (PAF) desenvolvem adenomas duodenais. Objetivo: Avaliar a eficacia e seguranca da excisao endoscopica de adenomas duodenais em doentes com PAF. Métodos: Incluidos todos os doentes com PAF submetidos a terapeutica endoscopica de adenomas duodenais ≥10 mm entre janeiro/2010-fevereiro/2021. Resultados: Em 151 familias com PAF, incluidos 22 doentes (50 lesoes): 54.5% mulheres; mediana do follow-up 12.3 (IQR: 6.0­19.0) anos. Primeira endoscopia terapeutica (ressecao de polipos duodenais ≥10 mm) ocorreu numa mediana de idades 41.0 (IQR: 33.0­58.2) anos. Em 54.5% dos casos, foi necessaria uma nova endoscopia terapeutica. Dimensao mediana do maior adenoma: 15 mm (IQR: 10­18 mm); ressecao realizada em piecemeal em 63.1% e em bloco nos restantes. Em dois casos, a ressecao endoscopica foi incompleta (fibrose em local de ressecao previa:1; posicionamento: 1). Complicacoes em 6.3% das lesoes ressecadas (4 doentes): 2 imediatas (hemorragia e perfuracao, manejadas endoscopicamente); 4 na primeira semana (1 hemorragia controlada endoscopicamente, 2 pancreatites ligeiras tratadas conservadoramente, 1 perfuracao com necessidade de cirurgia; as duas ultimas apos ampulectomia). A avaliacao histologica revelou adenomas com displasia de baixo grau em 90.1%; nenhum adenocarcinoma. Um doente com doenca Spigelman IV nao controlavel endoscopicamente realizou duodenopancreatectomia (sem cancro). Conclusão: A vigilancia e tratamento endoscopicos de adenomas duodenais em doentes com PAF revelaram-se seguros e eficazes na prevencao de cancro duodenal.

Routine Immunohistochemical Analysis of Mismatch Repair Proteins in Colorectal Cancer-A Prospective Analysis.

Recognition of a hereditary colorectal cancer (CRC) syndrome is crucial and Lynch Syndrome (LS) is the most frequent immunohistochemistry (IHC)-screening for mismatch repair proteins (MMR) deficiency in CRC is therefore advocated. An unicentric cohort study was conducted in a central Oncological Hospital to assess its results. All patients under 70 years-old admitted between July 2017-June 2019 and submitted to surgery for CRC were included. Of 275 patients, 56.0% were male, median age 61.0 (IQR:54.5-65.0), with synchronous tumors in six. Histology revealed high grade adenocarcinoma in 8.4%; mucinous and/or signet ring differentiation in 11.3%; and lymphocytic infiltration in 29.8%. Amsterdam (AC) and Bethesda (BC) Criteria were fulfilled in 11 and 74 patients, respectively. IHC revealed loss of expression of MMR proteins in 24 (8.7%), mostly MLH1 and PMS2 (n = 15) and PMS2 (n = 4). Among these, no patients fulfilled AC and 13 fulfilled BC. BRAF mutation or MLH1 promoter hypermethylation was found in four patients with MLH1 loss of expression. Genetic diagnosis was performed in 51 patients, 11 of them with altered IHC. LS was diagnosed in four, and BC was present in three. One patient would not have been diagnosed without routine IHC screening. These results strengthen the important role of IHC screening for MMR proteins loss of expression in CRC.

Pediatric Colorectal Cancer: A Heterogenous Entity.

INTRODUCTION: Colorectal cancer (CRC) is extremely rare in pediatric age. A poor outcome has been reported. AIMS: We aimed to characterize a group of pediatric CRC patients. MATERIALS AND METHODS: All patients with CRC below 18 years old registered in our Familial Cancer Risk Clinic (2002-2016) were included. Clinical and histologic features were evaluated. Germline mutations, microsatellite instability, and DNA mismatch repair proteins expression were analyzed. RESULTS: Five patients were included (3 males; mean age at diagnosis: 14.2 years (range, 9 to 17 y) and 4/5 had family history of cancer in second-degree relatives. With a maximum follow-up of 5.6 years, 2/5 patients died after 10 and 24 months, and 1 recurred after 15 months. All tumors were ≥pT3N2 and 3/5 presented signet ring cells/mucinous histology, corresponding to cases with stronger family history of cancer. Nevertheless, all CRCs analyzed (n=4) were microsatellite stable and/or expressed all mismatch repair proteins. Loss of heterozygosity for the 3 Bethesda dinucleotide markers was detected in 1/3 informative CRCs. A likely pathogenic germline MSH2 mutation was identified in only 1 patient. CONCLUSIONS: Pediatric CRC presented advanced disease and poor prognosis. These tumors had distinct histologic and molecular presentations, resembling features from different carcinogenic pathways, thus suggesting a heterogenous nature.

Real-Time Optical Diagnosis of Colorectal Polyps in the Routine Clinical Practice Using the NICE and WASP Classifications in a Nonacademic Setting.

BACKGROUND: Narrow-band imaging (NBI) allows "in vivo" classification of colorectal polyps. OBJECTIVES: We evaluated the optical diagnosis by nonexpert community-based endoscopists in routine clinical practice, the impact of training, and whether the endoscopists could achieve the threshold for the "do not resect" policy. METHODS: This was an observational study performed in two periods (P1 and P2). Endoscopists had no prior experience in NBI in P1 and applied the technique on a daily basis for 1 year before participation in P2. Lesions were classified by applying the NBI International Colorectal Endoscopic (NICE) and Workgroup serrAted polypS and Polyposis (WASP) classifications, simultaneously. RESULTS: A total of 290 polyps were analyzed. The overall accuracy of optical diagnosis was 0.75 (95% CI 0.68-0.81) in P1, with an increase to 0.82 (95% CI 0.73-0.89) in P2 (p = 0.260). The accuracy of the NICE/WASP classifications to differentiate adenomatous from nonadenomatous histology was 0.78 (95% CI 0.72-0.84) in P1 and 0.86 (95% CI 0.77-0.92) in P2 (p = 0.164); assignments made with a high confidence level achieved statistical significance (13% improvement, 95% CI 3-22%; p = 0.022). The negative predictive value for adenomatous histology of diminutive rectosigmoid polyps was 81% (95% CI 64-93%) and 80% (95% CI 59-93%) in P1 and P2, respectively. CONCLUSIONS: Nonexpert endoscopists achieved moderate accuracy for real-time optical diagnosis of colorectal lesions with the NICE/WASP classifications. The overall performance of the endoscopists improved after sustained use of optical diagnosis, but did not achieve the standards for the implementation of the "do not resect" strategy.

INTRODUÇÃO: O narrow-band imaging (NBI) permite a classificação "in-vivo" dos pólipos colo-rectais. OBJECTIVOS: Avaliámos o diagnóstico óptico na prática clínica diária em endoscopistas da comunidade, sem experiência prévia em NBI, o impacto do treino e se estes conseguiam atingir o limiar da estratégia de "não ressecar". MÉTODOS: Estudo observacional, realizado em dois períodos (P1 e P2). Os endoscopistas não apresentavam experiência prévia em NBI em P1 e aplicaram a técnica diariamente durante um ano antes da participação em P2. As lesões foram classificadas aplicando as classificações NBI International Colorectal Endoscopic (NICE) e Workgroup serrAted polypS and Polyposis (WASP), simultaneamente. RESULTADOS: Foram analisados 290 pólipos. A acuidade global do diagnóstico óptico foi de 0.75 (IC 95%, 0.68-0.81) em P1, aumentando para 0.82 (IC 95%, 0.73-0.89) em P2 (p = 0.260). A acuidade das classificações de NICE/WASP na diferenciação de histologia adenomatosa de não-adenomatosa foi de 0.78 (IC 95%, 0.72-0.84) em P1, e 0.86 (IC 95%, 0.77-0.92) em P2 (p = 0.164); as predições realizadas com alto grau de confiança alcançaram significado estatístico (melhoria de 13%, IC 95%, 3-22%; p = 0.022). O valor preditivo negativo para histologia adenomatosa dos pólipos diminutos recto-sigmóides foi de 81% (IC 95%, 64-93%) e 80% (IC 95%, 59-93%), em P1 e P2, respetivamente. CONCLUSÕES: Endoscopistas sem experiência em NBI alcançaram acuidade moderada no diagnóstico óptico em tempo real de lesões colo-rectais, utilizando as classificações de NICE/WASP. O desempenho global melhorou após a utilização contínua do diagnóstico óptico, mas não alcançou o limiar definido para a implementação da estratégia de "não ressecar".

The nonsense mutation MSH2 c.2152C>T shows a founder effect in Portuguese Lynch syndrome families.

The mutational spectrum of the MMR genes is highly heterogeneous, but specific mutations are observed at high frequencies in well-defined populations or ethnic groups, due to founder effects. The MSH2 mutation c.2152C>T, p.(Gln718*), has occasionally been described in Lynch families worldwide, including in Portuguese Lynch syndrome families. During genetic testing for Lynch syndrome at the Portuguese Oncology Institutes of Porto and Lisbon, this mutation was identified in 28 seemingly unrelated families. In order to evaluate if this alteration is a founder mutation, haplotype analysis using microsatellite and SNP markers flanking the MSH2 gene was performed in the 28 probands and 87 family members. Additionally, the geographic origin of these families was evaluated and the age of the mutation estimated. Twelve different haplotypes were phased for 13 out of the 28 families and shared a conserved region of ∼3.6 Mb. Based on the mutation and recombination events observed in the microsatellite haplotypes and assuming a generation time of 25 years, the age estimate for the MSH2 mutation was 273 ± 64 years. The geographic origins of these families were mostly from the Northern region of Portugal. Concluding, these results suggest that the MSH2 c.2152C>T alteration is a founder mutation in Portugal with a relatively recent origin. Furthermore, its high proportion indicates that screening for this mutation as a first step, together with the previously reported Portuguese founder mutations, may be cost-effective in genetic testing of Lynch syndrome suspects of Portuguese ancestry.

Bilateral breast fibromatosis after silicone prosthetics in a patient with classic familial adenomatous polyposis: A case report.

Breast fibromatosis is a benign fibroblastic proliferation accounting for less than 0.2% of breast tumors. It presents sporadically or as a manifestation of familial adenomatous polyposis (FAP). Fibromatosis in FAP may develop in patients with adenomatous polyposis coli (APC) gene mutations at any location through the gene. Notably, there is an increased risk if mutation is downstream codon 1400. The present case report described a 33-year-old woman with recurrent bilateral breast fibromatosis after breast implants in a context of classic FAP. APC mutation (codon-935) was detected at the age of 16. In the same year, a thyroidectomy for a cribriform-morular papillary thyroid carcinoma (pT1) was performed. Seven years later, a prophylactic total colectomy with >100 adenomas without invasive carcinoma was performed and the patient was kept under surveillance. At the age of 30 years old, she underwent breast silicone implantation for cosmetic reasons. One year later, bilateral breast tumors were diagnosed in core biopsy as fibromatosis (nuclear ß-catenin+, estrogen receptors-). After no success with medical treatment with tamoxifen, bilateral mastectomy was performed. The patient relapsed one year later and a fibromatosis lesion in the right thoracic wall was excised again. The patient demonstrated no signs of relapse 24 months after the surgery. This rare case illustrates that the increased risk of developing fibromatosis in patients with FAP, even in the classic form, should be considered before deciding to place breast implants.

Colorectal cancer surveillance in Portuguese families with lynch syndrome: a cohort study.

PURPOSE: Lynch syndrome (LS) is associated with a high risk of colorectal cancer (CRC). The aim of this study was to assess the cumulative risk for the development of colorectal adenomas or carcinomas in a LS CRC surveillance program and to audit the quality of the endoscopic procedures. METHODS: We evaluated 147 asymptomatic LS mutation carriers, without previous CRC, in a surveillance program with colonoscopy every 12-18 months, between 2005 and 2016. Data was obtained by retrospective review of colonoscopy reports and hospital clinical files. The main outcome was assessed using Kaplan-Meier curves. Logistic regression was used to study the risk of developing adenomas. RESULTS: Patients were under surveillance for 1092 observation years (mean, 7.7 years/patient). Most exams presented adequate bowel preparation (83.5%) and 99.2% achieved cecal intubation. The estimated risk for adenomas at age 60 was 75.6% in men (95%CI, 60.5-88.3) and 65.5% in women (95%CI, 50.8-79.7). Male gender (OR 2.4; 95%CI, 1.2-4.9; p = 0.018) and age at start of surveillance > 40 years (OR 3.7; 95%CI, 1.8-7.7; p < 0.001) were independent risk factors for adenoma detection. CRC was diagnosed in 11 patients with an estimated cumulative risk at age 60 of 18.4% (95%CI, 9.2-34.8%); 72.7% of CRC were classified as stage I; no patient died from CRC. CONCLUSION: A colonoscopic surveillance program in LS patients allowed the detection of adenomas in a large group of mutation carriers and diagnosis of early-stage carcinomas. Our findings may help other teams to adopt similar strategies or to refer patients early to specialized centers.

Gastric malt lymphoma: Analysis of a series of consecutive patients over 20 years.

INTRODUCTION AND AIMS: Gastric mucosa-associated lymphoid tissue (MALT) lymphoma is closely associated with Helicobacter pylori (HP) infection. Our aim was to evaluate demographic, clinical and endoscopic characteristics of gastric MALT lymphoma patients, as well as to analyse response to treatment and factors that affect complete remission (CR) and relapse. We also assessed the long-term prognosis. METHODS: The study involved a retrospective evaluation of consecutive patients admitted with gastric MALT lymphoma (1993-2013). RESULTS: A total of 144 patients (76 men; mean age 56) were included. At stage EI, 94/103 patients (92%) received HP eradication and 78 (83%) achieved CR after a mean period of 7 months (2-63 months) and 67 (86%) remained in CR after a mean follow-up time of 105 months. HP infection status (p = 0.004) and lymphoma localisation to the antrum plus body (p = 0.016) were associated with higher and lower CR rates, respectively. Relapse occurred in 11/78 (14%) patients after a mean period of 21 months. The absence of HP re-infection (p = 0.038), the need of only one eradication regimen (p = 0.009) and antrum lymphomas (p = 0.031) correlated with lower relapse rates. At stage EII, HP eradication was performed in 17/24 patients but only five experienced CR (30%). Among 16 patients diagnosed at stage EIV, nine achieved CR after chemotherapy ± surgery and 3/7 without remission died due to disease progression. The 5- and 10-year overall disease free survival rates were 90.5% and 79.1%, respectively. CONCLUSIONS: Most patients were diagnosed at an early stage. Eradication therapy was highly effective in inducing complete remission. Long-term evaluation showed that the long-term prognosis was very favourable.

Serrated polyposis associated with a family history of colorectal cancer and/or polyps: The preferential location of polyps in the colon and rectum defines two molecular entities.

Serrated polyposis (SPP) is characterized by the development of multiple serrated polyps and an increased predisposition to colorectal cancer (CRC). In the present study, we aimed to characterize, at a clinical and molecular level, a cohort of SPP patients with or without a family history of SPP and/or polyps/CRC (SPP-FHP/CRC). Sixty-two lesions from 12 patients with SPP-FHP/CRC and 6 patients with sporadic SPP were included. The patients with SPP-FHP/CRC presented with an older mean age at diagnosis (p=0.027) and a more heterogeneous histological pattern of lesions (p=0.032) than the patients with sporadic SPP. We identified two molecular forms of SPP-FHP/CRC, according to the preferential location of the lesions: proximal/whole-colon or distal colon. Mismatch repair (MMR) gene methylation [mutS homolog 6 (MSH6)/mutS homolog 3 (MSH3)] or loss of heterozygosity (LOH) of D2S123 (flanking MSH6) were detected exclusively in the former (p=3.0x10-7), in most early lesions. Proximal/whole­colon SPP-FHP/CRC presented a higher frequency of O-6-methylguanine-DNA methyltransferase (MGMT) methylation/LOH, microsatellite instability (MSI) and Wnt mutations (19/29 vs. 7/17; 16/23 vs. 1/14, p=2.2x10-4; 15/26 vs. 2/15, p=0.006; 14/26 vs. 4/20, p=0.02) but a lower frequency of B-raf proto-oncogene, serine/threonine kinase (BRAF) mutations (7/30 vs. 12/20, p=0.0089) than the distal form. CRC was more frequent in cases of Kirsten rat sarcoma viral oncogene homolog (KRAS)-associated proximal/whole-colon SPP-FHP/CRC than in the remaining cases (4/4 vs. 1/8, p=0.01). Thus, SPP-FHP/CRC appears to be a specific entity, presenting two forms, proximal/whole-colon and distal, which differ in the underlying tumor initiation pathways. Early MGMT and MMR gene deficiency in the former may underlie an inherited susceptibility to genotoxic stress.

Esophageal stenosis with sloughing esophagitis: A curious manifestation of graft-vs-host disease.

We report a case of a 56-year-old woman with a history of allogenic bone marrow transplantation for two years, complaining with dysphagia and weight loss. Upper endoscopy revealed esophageal stenosis and extensive mucosa sloughing. Biopsies confirmed the diagnosis of graft-vs-host disease (GVHD). Balloon dilation, corticosteroids and cyclosporin resulted in marked clinical improvement. Gastrointestinal tract is involved in the majority of patients with chronic GVHD. Esophageal manifestations are rare and include vesiculobullous disease, ulceration, esophageal webs, casts or strictures. Sloughing esophagitis along with severe stenosis requiring endoscopic dilation has never been reported in this context.

Hyperplastic polyp? Look again... the impact of the new classification for serrated polyps.

INTRODUCTION: The World Health Organization reviewed the classification for serrated colonic polyps in 2010. A new entity, sessile serrated adenoma, was included with two variants: with and without cytological dysplasia. This lesion's malignant potential has been recognized and according to the new classification, many polyps may be reclassified. The impact of this change is yet to be assessed. OBJECTIVE: Analyze the proportion of lesions that were reclassified according to the new World Health Organization classification and the variables that influenced it. MATERIAL AND METHODS: Every patient with at least one sessile serrated adenoma diagnosed in a 5 year period was included. All polyps (regardless of type) resected during the study period were reviewed. Data concerning polyp's characteristics and patient variables were collected. Forty consecutive patients were included [13 female, mean age at 1st sessile serrated adenoma -59 yrs (34-80)]. RESULTS: Were reviewed 247 polyps: hyperplastic--42%; conventional adenomas--29%; sessile serrated adenoma--24%; serrated adenomas--5%. Sixty-three polyps were reclassified: 43 hyperplastic, 12 serrated adenomas, 7 sessile serrated adenoma and 1 conventional adenoma with low grade dysplasia. Reclassification was significantly greater for hyperplastic polyps when compared with the other subtypes. Forty-three of one hundred and four (41%) hyperplastic polyps were reclassified all as sessile serrated adenoma. In these polyps the probability of reclassification was independent from polyp location but was greater if polyp size ≥ 5 mm. DISCUSSION: This is a single center, rectrospective study. The fact that it was done in an Oncology Referral Institution with a Family Risk Clinic may have influenced the results. Nevertheless the impressive reclassification rate for Hyperplastic Polyps and the fact that they were reclassified mainly as Serrated Adenomas makes these results relevant to daily practice. CONCLUSION: Our results suggest that, according to the new World Health Organization classification for serrated colonic polyps, a considerable proportion of hyperplastic polyps will be reclassified. The serrated pathway of colorectal carcinogenesis has probably been underestimated and at-risk patients may have been under inappropriate surveillance.

Introdução: A Organização Mundial de Saúde reviu a classificação para os pólipos serreados do cólon em 2010. Uma nova entidade, o adenoma serreado séssil, foi incluída com duas variantes: com e sem displasia citológica. O potencial de malignização desta lesão foi reconhecido e, de acordo com a nova classificação, muitos pólipos poderão ser reclassificados. O impacto desta mudança ainda não foi aferido. Objectivo: Analisar a proporção de lesões reclassificadas de acordo com a nova classificação da Organização Mundial de Saúde e as variáveis que a influenciaram. Material e Métodos: Todos os doentes com pelo menos um adenoma serreado séssil diagnosticado num período de cinco anos foram incluídos. Todos os pólipos (independentemente do tipo histológico) ressecados durante o período considerado foram revistos. Recolhidas variáveis dos pólipos e dados dos doentes. Incluídos 40 doentes consecutivos [13 mulheres, idade média no diagnóstico do 1º adenoma serreado séssil - 59 anos (34-80)]. Resultados: Revistos 247 pólipos: hiperplásicos - 42%; adenomas convencionais - 29%; adenoma serreado séssil - 24%; adenomas serreados-5%. Reclassificados 63 pólipos: 43 hiperplásicos, 12 adenomas serreados, 7 adenoma serreado séssil e 1 adenoma convencional com displasia de baixo brau. A reclassificação foi significativamente mais provável para os pólipos hiperplásicos em relação aos outros subtipos. 41% (43/104) dos pólipos hiperplásicos foram reclassificados como adenoma serreado séssil. Para estes pólipos a probabilidade de reclassificação foi independente da localização mas maior se a dimensão ≥ 5 mm. Discussão: Este é um estudo rectrospectivo que foi conduzido num único Centro Oncológico de Referenciação com uma Clínica de Risco Familiar associada, o que pode ter influenciado os resultados. No entanto, a elevada taxa de reclassificação para os pólipos hiperplásicos e o facto de estes terem sido reclassificados quase sempre como adenomas serreados tornam estes resultados relevantes para a prática do dia a dia. Conclusão: Os nossos resultados mostram que, de acordo com a nova classificação da Organização Mundial de Saúde para os pólipos serreados, uma proporção considerável de pólipos hiperplásicos seria reclassificada. A via serreada de carcinogénese colorectal tem sido provavelmente subestimada e doentes em risco podem estar sob vigilância inadequada.

Dispositivo fotobiomodulador para prevenção e tratamento de hiperqueratose de teto em vacas leiteiras / Photobiomodulation device for prevention and treatment of teat hyperkeratosis in dairy cows

As mastites estão entre as principais causas de prejuízo para produtores de leite. Em casos graves de hiperqueratose, o canal do teto pode se tornar uma barreira mais fácil para que as bactérias penetrem na glândula mamária. Os objetivos deste estudo foram avaliar um dispositivo fotobiomodulador de LED para tratamento e prevenção de hiperqueratose de teto e prevenção da mastite subclínica em um rebanho de leite com alta prevalência de hiperqueratose (35,3 por cento de casos graves). Foram utilizadas 60 primíparas para o experimento de prevenção e 30 vacas com hiperqueratose para o experimento terapêutico. Em ambos os experimentos, metade dos animais foram tratados com o dispositivo fotobiomodulador três vezes por semana, durante 6 semanas. Os outros animais foram os controles. Imagens fotográficas digitalizadas foram realizadas na avaliação inicial e, semanalmente, por 6 semanas consecutivas. Nas primíparas, novas avaliações foram realizadas entre 6 e 7 meses de lactação. Para avaliação da mastite subclínica, contagem de células somáticas (CCS) foram feitas mensalmente. No experimento preventivo, o diâmetro externo das lesões permaneceu constante nos tetos do grupo tratado, enquanto houve aumento no grupo controle. No experimento terapêutico não foram observadas diferenças estatísticas entre as variáveis de hiperqueratose. Contudo, o grupo tratado apresentou menor incidência de mastites subclínicas (CCS < 250 células/mL) por lactação do que o grupo controle (P<0,05). Em conclusão, o tratamento não foi efetivo em prevenir o desenvolvimento ou reduzir lesões instaladas de hiperqueratose de teto. Contudo, o uso protótipo se mostrou útil e promissor como adjuvante na prevenção do aumento de tamanho das lesões de hiperqueratose de teto em primíparas e como forma de reduzir incidência de mastite subclínicas em vacas leiteiras já acometidas.

Mastitis consistis one of the main problems of milk production, mainly due to the production losses and the rising cost of milk. In case of severe hyperkeratosis, the teat canal can become an easier barrier for the bacteria to penetrate. The objeSctive of this study was to assess a phototherapy device construct with LED light for prevention and treatment of teat hyperkeratosis in a dairy cattle herd with high prevalence (35.3 percent of severe cases). 60 primiparous cows were used in the preventive experiment and 30 cows with hyperkeratosis were used in the therapeutic experiment. In both experiments, half of the cows started to be treated in early lactation using the phototherapy device three times per week for 6 weeks. The other cows were the controls. Hyperkeratosis was assessed by scoring and by morphometric analyses of teat images that were taken at baseline and then weekly for 6 consecutive weeks. In the preventive experiment, more images were taken later, between 6 and 7 months of the first lactation. Somatic cell counts (SCC) were performed monthly. In the preventive experiment, the outer diameter of the teat lesions remained constant in the treated group, whereas cows of the control group showed a significant increase at the end of lactation. In the therapeutic groups, no statistical differences for teat hyperkeratosis variables were seen between groups. However, the incidence of subclinical mastitis (SCC > 250 cells/mL) during lactation was lower in the treated group (P<0.05). In conclusion the phototherapy protocol did not prevent the development in primiparous or ameliorate previous hyperkeratosis lesions in cows. However, the prototype was considered useful as an adjunct in preventing the increase in the size of teat hyperkeratosis lesions and also as a way to reduce subclinical mastitis incidence in affected dairy cows.

Endoscopic mucosal resection of superficial colorectal neoplasms: review of 140 procedures.

INTRODUCTION AND AIMS: Endoscopic mucosal resection (EMR) has been shown to be useful in the removal of large colorectal sessile and flat lesions, avoiding the need for surgical resection. The aim of this study was to evaluate the efficacy and safety of EMR in colorectal lesions using the inject-and-cut technique. MATERIAL AND METHODS: Based on the review of colonoscopy reports, performed from February 2007 and February 2010, resected lesions = 10 mm in diameter were selected for the study. The endoscopic and histologic characteristics, complications, follow-up and surgical need were recorded. RESULTS: During the study period we performed 140 EMRs among 133 patients (82 men; mean age 64.4 ± 12.4 years). The majority of lesions were located proximal to the hepatic flexure (47.8%). Lesions mean size was 18.5 ± 8.5 mm. Morphologically lesions were classified as: Is-60; IIa-54; IIb-14; IIa+IIc-12. En-bloc resection was performed in 56.4% of cases. Lesions > 20mm in size were independently associated with a higher rate of piecemeal resection (OR: 13.7; 95% CI: 3.8-49.6; p < 0.0001) and residual lesion (OR: 7.3;95% CI: 1.6-34.2; p = 0.012). A complete endoscopic clearance was achieved in 91.4% of cases. Histological classification: non-specific alterations-1; hyperplastic polyp-8; adenoma-124; adenocarcinoma-7. The complication rate was 5.7% (6 intra-procedural bleeding; 1 delayed bleeding; 1 perforation). Until now, 144 follow-up colonoscopies were performed in 90 patients. Local recurrence occurred in 17/90 (18.9%), 10 of whom were managed with a new EMR. The recurrence rate was not affected by the lesion's dimension, location,and resection type. Twenty-one patients (15%) were referred for surgery, mainly because of incomplete resection of the index lesion. CONCLUSION: EMR was effective and safe in the treatment of colorectal sessile and flat lesions. Lesions larger than 20mm were frequently associated with piecemeal resections, which did not lead to a higher recurrence rate. EMR is feasible for managing local recurrence.

Bethesda criteria for microsatellite instability testing: impact on the detection of new cases of Lynch syndrome.

In 1997 Bethesda Guidelines (BG) were established and in 2004 those criteria were revised (RBG), with the main goal of selecting colorectal cancers (CRC) that should be subjected to microsatellite instability (MSI) testing. High microsatellite instability (MSI-H) is an intermediate marker for mutational analysis of the mismatch repair (MMR) genes involved in the genesis of Lynch Syndrome (LS). We aimed to evaluate and compare BG/RBG in the detection of MSI-H and subsequent identification of pathogenic MMR genes mutations. We included 174 patients with CRC and indication for MSI analysis according to BG or RBG. MSI testing was performed with the Bethesda markers and mutational analysis of MLH1, MSH2 and MSH6 genes undertaken with DGGE, MLPA and direct sequencing. One hundred fourteen of 174 patients (65.5 %) fulfilled BG and all of them RBG. With the BG, MSI-H was detected in 37/114 (32.5 %) CRCs and mutational analysis was positive in 14/37 (37.8 %) patients. The RBG led to detection of MSI-H in 49/174 (28.2 %) of the CRCs, having the mutational analysis been positive in 16/49 (32.7 %) patients. We could identify 14/114 (12.3 %) new cases of LS, through BG and 16/174 (9.2 %) via RBG. BG presented a similar overall percentage for the detection of MSI-H and mutations when compared with RBG. RBG implicated the analysis of more patients, though they gave rise to detection of two additional LS cases. This difference has a significant impact on the establishment of preventive measures, mainly for CRC, in all the mutation-carriers belonging to these families.

Familial colorectal cancer type X syndrome: two distinct molecular entities?

In a fraction of families fulfilling the Amsterdam criteria for hereditary non-polyposis colorectal cancer, colorectal cancers are microsatellite stable and DNA mismatch repair gene (MMR) mutations are not found. These families were designated as familial colorectal cancer type X (FCCTX). We aimed to characterise a group of FCCTX families defined by the Amsterdam criteria and MSS tumours at clinical and molecular level. Twenty-four tumours from 15 FCCTX families were analysed for loss of known tumour suppressor gene (TSG) loci (APC, TP53, SMAD4 and DCC), MGMT and MMR genes promoter methylation, and also APC and KRAS somatic mutations. FCCTX families presented specific clinical features: absence of endometrial tumours, high adenoma/carcinoma ratio (1.91) and prevalence of rectal cancers (13/27, 48%). New molecular features were found: the majority of FCCTX tumours (13/18; 72%) presented TSG loss. TSG loss positive tumours presented frequent APC and KRAS somatic mutations and MGMT methylation [10/13 (77%), 7/13 (54%) and 6/11 (54%), respectively]. In TSG loss negative tumours (5/18; 28%), the same molecular events were found in 2/5 (40%), 2/5 (40%) and 1/3 (33%) tumours, respectively. Transition mutations in KRAS were more frequent among MGMT methylated tumours than in unmethylated [5/8 (63%) vs. 1/10 (10%), P = 0.03]. Although sharing similar clinical features, at least two different molecular entities should exist among FCCTX families, one whose tumours present frequent TSG loss, APC and KRAS somatic mutations, and MGMT promoter methylation, and a second, lesser predominant, with no evidence of TSG loss and rarely presenting promoter methylation.

Colorectal cancers show distinct mutation spectra in members of the canonical WNT signaling pathway according to their anatomical location and type of genetic instability.

It is unclear whether the mutation spectra in WNT genes vary among distinct types of colorectal tumors. We have analyzed mutations in specific WNT genes in a cohort of 52 colorectal tumors and performed a meta-analysis of previous studies. Notably, significant differences were found among the mutation spectra. We have previously shown that in familial adenomatous polyposis, APC somatic mutations are selected to provide the "just-right" level of WNT signaling for tumor formation. Here, we found that APC mutations encompassing at least two beta-catenin down-regulating motifs (20 a.a. repeats) are significantly more frequent in microsatellite unstable (MSI-H) than in microsatellite stable (MSS) tumors where truncations retaining less than two repeats are more frequent (P = 0.0009). Moreover, in cases where both APC hits are detected, selection for mutations retaining a cumulative number of two 20 a.a. repeats became apparent in MSI-H tumors (P = 0.001). This type of mutations were also more frequent in proximal versus distal colonic tumors, regardless of MSI status (P = 0.0008). Among MSI-H tumors, CTNNB1 mutations were significantly more frequent in HNPCC than in sporadic lesions (28% versus 6%, P < 10-6) and were preferentially detected in the proximal colon, independently of MSI status (P = 0.017). In conclusion, the observed spectra of WNT gene mutations in colorectal tumors are likely the result from selection of specific levels of beta-catenin signaling, optimal for tumor formation in the context of specific anatomical locations and forms of genetic instability. We suggest that this may underlie the preferential location of MMR deficient tumors in the proximal colon.

[Familial colorectal cancer type X: clinical, pathological and molecular characterization]. / Carcinoma colorectal familiar de tipo X: caracterização clínica, patológica e molecular.

BACKGROUND: Some families fulfilling the Amsterdam Criteria (AC) differ from the Lynch syndrome (LS) in that colorectal cancers (CRC) do not present microsatellite instability (MSI) and DNA mismatch repair gene mutations are not found. These families have been designated as Familial Colorectal Cancer type X (XS) and their genetic basis remains unknown. AIMS: In families fulfilling AC for LS: 1) To perform MSI testing in CRC and to correlate it with clinical and pathological characteristics and with the mutational analysis in the DNA mismatch repair genes; 2) In cases suggestive of XS, to study the suppressor pathway (SP) of carcinogenesis. PATIENTS AND METHODS: 45 patients with CRC, from 41 families fulfilling AC, were included. Clinical and pathological data were recorded. MSI testing was performed with the Bethesda marker panel and mutational analysis in MLH1, MSH2 and MSH6 genes was undertaken by DGGE, MLPA and direct sequencing. To study the SP, loss of heterozigoty was evaluated at the following loci: APC, p53, DCC and SMAD4 genes. RESULTS: 33/41 (80%) and 8/41 (20%) families presented high-grade microsatellite instability (MSI-H) and microsatellite stable (MSS) CRC, respectively. In families suggestive of XS, a smaller number of CRC and less frequent spectrum associated tumors were detected. In comparison with MSI-H CRC, MSS CRC were preferentially located at the distal colon/rectum and less often presented mucous production or lymphocytic infiltrate. In 70% of families with MSI-H CRC, a pathogenic mutation in one of the DNA mismatch repair genes was identified, as opposed to none in the group with MSS CRC. The SP was followed in 2 cases and an alternative one in other two. The remaining 4 cases were noninformative; however, 5/8 (63%) presented allelic losses in the APC gene. CONCLUSIONS: 1) Families fulfilling AC and harbouring MSS CRC presented particular characteristics, which reinforce the existence of a new entity, different from LS; 2) The designation of Familial Colorectal Cancer type X seems appropriate to classify an entity whose CRC follow an unclear carcinogenesis pathway and that presents an unknown genetic basis; 3) The designation of LS should be restricted to families with an identified pathogenic DNA mismatch repair gene mutation.

APC somatic mosaicism in a patient with Gardner syndrome carrying the E1573X mutation: report of a case.

We report a case of somatic APC mosaicism in an person with a clinical diagnosis of Gardner syndrome with features of attenuated polyposis coli and with an uninformative family history. In initial screening for APC mutations, the germline mutation E1573X was detected in a lower proportion than that predicted by a heterozygous mutation indicating the presence of somatic mosaicism. Pyrosequencing confirmed this hypothesis and quantified the presence of the mutation in approximately 18% of the blood lymphocytes. Mutational analysis performed in the offspring revealed a fully heterozygous E1573X mutation in 2 of the 3 individuals tested. The milder colonic phenotype exhibited by the index patient could be a consequence of the presence of the mosaicism in the colon mucosa. The detection of the mutation in other tissues and in the offspring suggests that it may have occurred early during embryogenesis, before the separation of the embryonic layers. The E1573X mutation is the most distal mutation in the APC sequence reported to date as a mosaic and, interestingly, in the context of Gardner syndrome with extensive extracolonic features. Mosaicism is an important consequence of de novo APC mutations and it should be considered in the management of apparently sporadic or de novo cases, particularly in the evaluation of the risk of siblings and offspring.

Aggressive phenotype of MYH-associated polyposis with jejunal cancer and intra-abdominal desmoid tumor: report of a case.

MYH-associated polyposis is an inherited autosomal recessive disease, linked to biallelic germline MYH mutations, which predisposes to the development of multiple colorectal adenomas and cancer. The colonic and extracolonic phenotype of this syndrome is very heterogeneous. We report the case of a young male patient with an aggressive MYH-associated polyposis phenotype. He presented at aged 30 years with more than 100 colonic polyps and 4 colonic adenocarcinomas. At aged 35 years, Spigelman Stage IV duodenal adenomatosis was detected. When he was 39 years old, he developed three synchronous jejunal adenocarcinomas and a mesenteric desmoid tumor. Based on this report, we believe that screening of the entire small bowel should be recommended in MYH-associated polyposis patients, especially in those with duodenal adenomas. Similar to patients with familial adenomatous polyposis, desmoid tumors also may be part of the clinical spectrum of MYH-associated polyposis and may prove to be a significant clinical problem in patients submitted to prophylactic colectomy.

Colorectal adenomas in young patients: microsatellite instability is not a useful marker to detect new cases of Lynch syndrome.

PURPOSE: Original Bethesda Guidelines proposed microsatellite instability analysis in colorectal adenomas from patients younger than aged 40 years to identify new cases of Lynch syndrome. We intended to evaluate the characteristics of colorectal adenomas from patients younger than aged 40 years to determine their microsatellite instability status and to correlate it with germline mutations in MLH1 and MSH2 genes. METHODS: Seventy-two adenomas from 58 patients were analyzed. Family history of colorectal cancer, location, and histology of adenomas were evaluated. Microsatellite instability testing was performed with BAT26 only or with the complete Bethesda panel. Germline mutational analysis was performed in MLH1 and MSH2 genes. RESULTS: Thirty-five patients had a family history of colorectal cancer and 16 of them belonged to Amsterdam Criteria positive families. The remaining 23 presented with sporadic adenomas. Microsatellite instability was found in seven adenomas from seven different patients, all belonging to Amsterdam Criteria-positive families. In six of these patients, a pathogenic germline mutation was identified. CONCLUSIONS: Adenomas diagnosed before aged 40 years presented microsatellite instability only in patients from families with clinical criteria for Lynch syndrome. According to our results, to detect new cases of Lynch syndrome, family history is more important than microsatellite instability testing in adenomas from young patients.