Low-cost colonoscopic simulator and colonoscope to train basic skills in colonoscopy during undergraduate studies

Objective: To develop a low-cost simulator model and a colonoscope with materials that are easily accessible to offer training on colonoscopy skills during undergraduate studies. Since this is the procedure of choice for colorectal cancer screening, the general practitioner must be able to recognize its main indications, preparation, and complications. Methods: Using materials such as a mannequin, a vehicle inspection camera, a conduit, polyvinyl chloride (PVC) pipe, acrylic, wood, and red paint, we built a simulator and a 150-cm long and 20-to-25-mm thick colonoscope. The colonoscope's handle and handhold were made of acrylic, the colonoscope's mobile end was made with articulated PVC rings, and the up and down movements were performed according to the traction of the steel cables. The camera attached to its distal end enables connection to a smartphone to view the image. In the simulator, the conduit was inserted into the mannequin to simulate the curvatures of the colon. Red spray paint was used to simulate the staining of the colonic mucosa in the inner region of the mannequin and the adventitial layer in the outer region. Results: We were able to build a simulator and a colonoscope with a total amount of R $ 182.82 (roughly US$ 36.50). Both were tested and proved to be useful in the acquisition of psychomotor and cognitive skills in colonoscopy. Conclusion The simulator and colonoscope developed by us are cost-effective, useful in the acquisition of psychomotor and cognitive skills in colonoscopy, and can facilitate the structuring of a training program for undergraduate students. (AU)

Watch and wait, worth It?

Background: The surgery with total mesorectal excision recommended by R. J. Heald in 1982 is the gold standard. Rectal cancer (RC) surgery has a morbidity rate ranging from 6 to 35%, and it can cause functional issues such as sexual, urinary, and bowel dysfunction in the long term. Neoadjuvant chemoradiotherapy (CRT) has been gaining ground in patients with lesions in the middle and lower rectum. The aim of the present study is to present the experience of a reference service in the treatment of RC. Patients and Methods: A retrospective study involving 53 patients diagnosed with RC between January 2017 and December 2019 with follow-up until December 2020. We examined tumor location, disease stage, digital rectal exam findings, carcinoembryonic antigen (CEA), therapeutic modality offered, and follow-up time. Results: A total of 32% of the patients were men and 68% were women, with a mean age of 60 years old. Location: upper rectum in 6 cases, middle rectum in 21 cases, and lower rectum in 26 cases with evolution from 9.8 to 13.5 months. The most frequent complaints were hematochezia and constipation. A total of 36 patients underwent neoadjuvant therapy: 11 complete clinical response (CCR) (30.5%), 20 (55.5%) partial clinical response (PCR), and no response in 5 patients (14%). The follow-up ranged from 12 to 48 months, with a mean of 30.5 months. A total of 25% of the patients had RC that went beyond the mesorectal fascia, and 22.64% had metastases in other parts of the body when they were diagnosed. Conclusion: Neoadjuvant radio and chemotherapy present themselves as an alternative in the treatment of rectal cancer. In 36 patients, 30.5% had a complete clinical response, 55.5% had a partial clinical response, and 14% had no response. It was worth doing the "Watch and Wait" (W&W) to sample. A definitive colostomy was avoided. However, it is necessary to expand the study to a larger follow-up and more patients. Additionally, it is necessary to implement a multicenter study. (AU)

Serum long-noncoding RNA H19 and beta-catenin as biomarkers for early diagnosis of colorectal cancer in egyptian patients: a case control study

Colorectal cancer (CRC) is the third most prevalent cancer and the second most common cause of cancer death; however, its early detection can improve the survival. Colonic polyps are considered one of the CRC's major risk factors. Throughout many biological processes and malignancies, the non-coding RNAs have essential functions. Certain long noncoding RNAs (lncRNAs), including H19, were supposed to be CRC possible biomarkers. Also, H19 has been reported to play a role in regulating the activity of beta-catenin, a protein that regulates cell-to-cell adhesion, as well as gene transcription. The current work aimed to investigate the potential significance of LncRNA H19 relative serum expression level by quantitative polymerase chain reaction (q-PCR) and beta-catenin by enzyme-linked immunosorbent assay (ELISA) as noninvasive biomarkers to discriminate between colorectal cancer and colonic polyps. The statistical analysis of the studied factors revealed that the serum expression of H19 and beta-catenin in cancer cases were substantially greater than colonic polyp cases and normal control. Conclusion: The relative expressions of H19 and beta-catenin in the serum can significantly discriminate patients with CRC from those with polyp and normal controls, which could help when screening for CRC. (AU)

Expression Levels of the CA9, WT1, and PRAME genes and genotyping-associated antigens for the diagnosis and prognosis of colorectal cancer

Background: Colorectal cancer (CRC) is the third most prevalent type of cancer worldwide, and is one of the major health problems in Asia, Africa, Europe, and America. The tumor antigens recently are of interesting indicators as diagnostic and prognostic tools, The aim of the present study is to detect the expression levels of carbonic anhydrase IX (CA9), the Wilms tumor gene (WT1), and the preferentially expressed antigen in melanoma (PRAME) in the peripheral blood of CRC patients in comparison with healthy controls. Methods: A prospective case-control study of CRC patients was conducted. We included 25 newly-diagnosed CRC eligible patients and obtained peripheral blood samples of them as well as 10 blood samples from the control group. All samples were then submitted to deoxyribonucleic acid (DNA) extraction and a molecular study through real-time polymerase chain reaction (PCR). Results: The CRC group consisted of 15 (60%) female and 10 (40%) male patients with a mean age of 50.52 ± 9.8 years, while the control group included 4 (40%) female and 6 (60%) male patients with a mean age of 47.7 ± 7.9 years. The CRC group, 24 (96%) of patient samples were CA9-positive with strong statistically significant differences (p < 0.00001; sensitivity: 96%; specificity: 90%). Regarding the WT1 gene, there were 11 (44%) positive samples in the CRC group, with no statistically significant differences (p = 0.055; sensitivity: 44%; specificity: 90%). The PRAME gene was positive in 9 (36%) samples in the CRC group, with no statistically significant differences (p = 0.357; sensitivity: 36%; specificity: 80%. Among CA9 (24 patients; 96%) of patients with CRC expressed positive results, in WT1 11(91.6%) CRC patients expressed gene, and in PRAME gene, 9 patients with CRC (81.8%) expressed positive results. Conclusion: Overexpression of the CA9 gene in CRC of high sensitivity and specificity to be used as a tool to discriminate CRC from benign associate with high accuracy compare to WT1 and PRAME genes. (AU)

Risk factors associated with colorectal cancer in octogenarians can help stratify the need for colonoscopy

Objective: Colonoscopy is increasingly performed in octogenarians for the detection of colorectal cancer (CRC), but its benefits may be outweighed by its risks. The aim of the present study was to identify the risk factors for CRC in octogenarians presenting for colonoscopy to help stratify the need for this procedure. Methods: A retrospective analysis of 434 patients aged ≥ 80 years referred for a colonoscopy between January 2018 and December 2019. Comparisons were made between those with and without CRC and advanced adenoma (AA). The primary endpoint was to identify the clinical variables predictive of CRC and AA, and the secondary endpoints were complications and death 30 days after the procedure. Results: Colonoscopy was performed in 434 octogenarians, predominantly for symptoms, with CRC in 65 (15.0%) patients. Iron deficiency was associated with a higher risk of having CRC identified on colonoscopy (odds ratio [OR]: 2.33; 95% confidence interval [95%CI] = 1.36-4.00), but not symptoms such as bleeding, weight loss, or diarrhea. A colonoscopy in the last 10 years was protective, with a lower risk of CRC (OR: 0.45; 95% CI = 0.22-0.93). Patients with both normal iron stores and a colonoscopy within 10 years had a 92.5% chance of not having CRC. No variables were predictive of AA. Patients with complications, including death, were older and more likely to have underlying cardiorespiratory disease. Conclusion: Iron status and colonoscopy within 10 years can be used to predict the risk of CRC in octogenarians. Those with low predicted risk, especially if older and with cardiorespiratory disease, should be considered for non-invasive tests, such as computed tomography (CT) colonography, over colonoscopy. (AU)

Surgical approach of megacecum secondary to descending colon tumor / Abordagem cirúrgica de megaceco secundário a tumor de cólon descendente

Intestinal obstruction is the most frequent clinical manifestation of colon tumors, most of which are located in the descending and recto-sigmoid colon. Emergency bowel obstruction surgery is associated with high mortality and morbidity risks and the ideal approach remains controversial. Multi-stage procedures and the use of stents as bridges for surgery are promising options. A case of a 61-year-old patient with an acute obstructive abdomen secondary to colorectal neoplasm is presented, with emphasis on its diagnosis and treatmen (AU)

Obstrução intestinal é a manifestação clínica mais frequente de tumores de cólon sendo esses, em sua maioria, localizados no cólon descendente e reto-sigmoide. A cirurgia de emergência para obstrução intestinal é associada a altos riscos de mortalidade e de morbidade e a abordagem ideal permanece controversa. Procedimentos em vários estágios e o uso de stents como ponte para cirurgia são opções promissoras. É apresentado um caso de paciente de 61 anos, com abdome agudo obstrutivo secundário à neoplasia colorretal, com ênfase em seu diagnóstico e tratamento (AU)

Analysis of patients undergoing colonoscopies and the importance of exam quality for colorectal cancer screening

Objective: To determine the impact of the quality of colonoscopy examination for colorectal cancer screening. Methods: Retrospective observational study ofmedical records from patients treated at the endoscopy and colonoscopy service of Hospital Universitário Evangélico Mackenzie (Curitiba, PR, Brazil) from January 2019 to January 2020. Results: The analysis was based on 337 medical records from patients with adenomas identified during colonoscopy, and 1,385 medical records from patients without adenomas. The estimated occurrence rate of diagnosis of adenoma during colonoscopy in the target population of the study was of 19.6%, with a 95% confidence interval ranging from 17.7 to 21.5%. Of the 337 patients with adenoma, 136 (40.4%) presented the advanced form. Statistical analysis indicated a significant association between the quality of colonoscopy preparation and test completion. Conclusion: The quality of colonoscopy images is a critical factor for colorectal cancer screening, as it leads to higher rates of adenoma detection and test completion. (AU)

Current status, controversy and challenge in the neoadjuvant immunotherapy of colorectal cancer / 中华胃肠外科杂志

Neoadjuvant therapy for colorectal cancer is widely used in rectal cancer, locally advanced colon cancer, and resectable metastatic and recurrent colorectal cancer. Mismatch repair deficient(dMMR) and microsatellite instablity-high (MSI-H) colorectal cancer patients who benefit from the efficacy of immune checkpoint inhibitors are expected to further improve the efficacy of traditional neoadjuvant therapy based on radiotherapy and chemotherapy. In this paper, the current status of immunotherapy (with emphasis on immune checkpoint inhibitors) is elucidated, and the opportunities of its application in neoadjuvant therapy are analyzed, including poor sensitivity of dMMR tumors to traditional therapy, good immune response of early tumors, predictable, manageable and controllable toxicity of immune checkpoint inhibitors. Colorectal cancer patients have growing and diverse needs to be met. Current controversies and challenges are analyzed, and the future directions are pointed out, including active screening of benefit groups, exploration of efficacy prediction markers, optimization of neoadjuvant immunotherapy models, attention to efficacy evaluation and new therapeutic endpoints. Neoadjuvant therapy should be effective, moderate and accurate based on the treatment target. It is the prerequisite and basis to guarantee medical safety and improve therapeutic effect to attach importance to the standardization and safety of clinical research and to pay attention to patients' interests and legal and ethical demands.

Artificial intelligence-assisted colonoscopy: a narrative review of current data and clinical applications

Colonoscopy is the reference standard procedure for the prevention and diagnosis of colorectal cancer, which is a leading cause of cancer-related deaths in Singapore. Artificial intelligence systems are automated, objective and reproducible. Artificial intelligence-assisted colonoscopy has recently been introduced into clinical practice as a clinical decision support tool. This review article provides a summary of the current published data and discusses ongoing research and current clinical applications of artificial intelligence-assisted colonoscopy.

Neoplasia primaria sincrónica de estómago, colon y recto: reporte de un caso / Synchronous stomach, colon and rectum primary neoplasias: a case report

Presentamos el caso de un paciente masculino de 40 años de edad, con estreñimiento de un año de evolución y antecedentes de enfermedad por reflujo gastroesofágico, se realiza endoscopia digestiva alta y baja y se realiza diagnóstico sincrónico de adenocarcinoma de estómago, recto y colon descendente, realizamos tomografía por emisión de positrones con tomografía computarizada pre quirúrgico y cirugía como tratamiento primario. Mostramos una descripción del caso y una revisión de la bibliografía.

We present the case of a 40-year-old man with a one year evolution constipation and a history of GERD. An upper and lower digestive endoscopy was performed and a synchronous diagnosis of adenocarcinoma of the stomach, rectum and descending colon was established. A PET-CT pre-surgical was performed and the surgery was carried out as primary treatment. We show a description of the case and a bibliographic review.

Postcolonoscopy colorectal cancer: an overview and future directions

Over the past decade, there has been a great interest in postcolonoscopy colorectal cancer (PCCRC). Its etiology is complex and multifactorial. Monitoring for PCCRC is even more complex. The strategies to decrease the incidence of PCCRC start by defining the problem, identifying the factors contributing to its development, followed by an attempt to define methods to decrease its incidence.We believe that the quality of the colonoscopy and the endoscopist's expertise are the key factors in decreasing the incidence of PCCRC. (AU)

Hemofilia adquirida como manifestación inicial de recidiva de adenocarcinoma colorrectal / Acquired hemophilia as the initial manifestation of colorectal cancer's recurrence

Resumen Presentamos el caso de un varón de 86 años con un hematoma espontáneo en el músculo ilíaco izquierdo y diagnóstico previo de cáncer de colon en 1998 (estadio pT3N0M0), tratado quirúrgicamente mediante colectomía transversal, considerado en remisión completa. Tras realización de estudios complementarios se demostró la presencia de autoanticuerpos inhibidores del Factor VIII que confirmaron el diagnóstico de hemofilia adquirida. Durante el ingreso el paciente presentó un sangrado digestivo bajo que conllevó al descubrimiento de recidiva del adenocarcinoma colorrectal tratado previamente. Respondió de forma favorable a la terapia inicial con corticoides sistémicos y el complejo coagulante anti inhibidor que incluye el Factor VII activado [FEIBA].

Abstract We report the case of an 86-year-old man presenting with a spontaneous hematoma in the left iliac muscle and previous diagnosis of colon cancer in 1998 (stage pT3N0M0) treated with transverse colectomy and considered in complete remission. After a complete study, it was possible to identify the presence of Factor VIII inhibitors antibodies that confirmed the presence of acquired hemophilia. During hospitalization the patient presented a lower gastrointestinal bleeding leading to the diagnosis of recurrence of a previously treated colorectal adenocarcinoma. He responded to initial therapy with systemic corticoids and anti-inhibitory coagulant complex which includes activated VII Factor [FEIBA].

Carcinoma colorrectal en niños y adolescentes / Colorectal carcinoma in children and adolescent

Si bien el carcinoma colorrectal (CCR) es la tercera enfermedad oncológica más frecuente en adultos, solo el 1-4 % ocurre en menores de 25-30 años. Su presentación suele confundirse con otras patologías, lo cual lleva a significativas demoras diagnósticas. Dada su baja incidencia, pocos pediatras se enfrentarán con algún caso a lo largo de su carrera. Sin embargo, existen en la niñez múltiples síndromes hereditarios que predisponen al CCR. El objetivo de esta revisión es brindar una actualización sobre los síndromes predisponentes al CCR. Se revisarán las indicaciones de tamizaje, dado que el diagnóstico precoz en estadios localizados es el principal factor pronóstico. Además, se fortalecerán las herramientas de consejería genética para el paciente y su familia. A su vez, se discutirán las manifestaciones clínicas e histológicas y los factores pronósticos propios del CCR en la población pediátrica. Si bien las guías de tratamiento se extrapolan de la experiencia en adultos, se resumirán los lineamientos terapéuticos.

Although colorectal carcinoma (CRC) is the third most common type of cancer in adults, only 1-4 % of cases are reported in individuals younger than 25-30 years. Its presentation is usually confused with other diseases, leading to significant delays in diagnosis. Given its low incidence, few pediatricians will see a case throughout their practice. However, multiple hereditary syndromes during childhood predispose to CRC.The objective of this review is to provide an update on syndromes predisposing to CRC. Screening indications will be reviewed because an early diagnosis during localized stages is the main prognostic factor. In addition, patient and family genetic counseling tools will be enhanced. In turn, the clinical and histological manifestations and prognostic factors typical of CRC in the pediatric population will be discussed. Although treatment guidelines are extrapolated from the adult experience, therapy guidelines will be summarized here.

Assessment of Quality Indexes in Colonoscopy in the Coloproctology Service of a Tertiary Private Hospital in Southern Brazil / Avaliação de índices de qualidade em colonoscopia em um serviço de coloproctologia de um hospital terciário privado do Sul do Brasil

Abstract Background Colorectal cancer (CRC) is the third most common cancer among men, and the second among women worldwide. In Brazil, the incidence andmortality of CRC continues to increase. In colonoscopies, adenoma detection rates (ADRs) higher than 25% are associated linearly with better outcomes and lower rates of interval cancer. Objective To assess the colonoscopy quality indexes. Methods This is a cross-sectional retrospective study in which anatomopathological data and data regarding the colonoscopies were collected from the patient records of Hospital Moinhos de Vento, in Southern Brazil. The exams were performed by doctors from the Colorectal Service from June to August 2015. Results A total of 430 exams were included. Most patients were women (60.9% [262]), with a mean age of 56.96 years. The cecal intubation rate was of 96.7% (416). The quality of the bowel preparation was excellent or good in 92.95% (396) of the cases. The average time of removal of the colonoscope in normal exams was of 6.15 minutes. Polyps were detected in 201 patients (46.7%), and adenomas, in 125 patients (29.1%); 12 patients (2.8%) had advanced adenomas, and 6 (2.3%) had malignant neoplasms. The proximal serrated lesion detection rate (PSLDR) was of 6.7% (29). The prevalence ratio (PR) of adenomas among men was 1.78 times greater than in women (95% confidence interval [95%CI]: 1.16-2.75). The PR of adenomas among people aged 50 years or older was 2.41 times that of those under 50 years of age (95%CI: 1.43-4.06). Conclusion The data obtained are in line with international quality criteria in colonoscopy. More studies are needed to assess the ADR in the Brazilian population.

Resumo Introdução O câncer colorretal (CCR) é o terceiro mais comum em homens e o segundo mais comum em mulheres em todo o mundo. A incidência e mortalidade do CRC continuam a aumentar no Brasil. Taxas de detecção de adenoma superiores a 25% em colonoscopias estão associadas linearmente a melhores resultados emenores taxas de câncer de intervalo. Objetivo Avaliar a qualidade das colonoscopias analisadas. Métodos Este é um estudo transversal e retrospectivo no qual dados anatomopatológicos e relacionados às colonoscopias foram coletados de registros dos pacientes do Hospital Moinhos de Vento, no Sul do Brasil. Os exames foram realizados por médicos do Serviço de Coloproctologia de junho a agosto de 2015. Resultados Foram incluídos 430 exames. A maioria dos pacientes era do sexo feminino (60,9% [262]), com idade média de 56,96 anos. A taxa de intubação cecal foi de 96,7% (416). A qualidade do preparo intestinal foi excelente ou boaem92,95% (396) dos casos.O tempomédio de retirada do colonoscópio emexames normais foi de 6,15 minutos. Pólipos foram detectados em 201 pacientes (46,7%), e adenomas, em 125 (29.1%); 12 pacientes (2,8%) tinhamadenomas avançados, e 6 (2,3%), neoplasias malignas. A taxa de detecção de lesões serrilhadas foi de 6,7% (29). A razão prevalência (RP) de adenomas emhomens foi de 1,78 vezes emrelação amulheres (intervalo de confiança de 95% [IC95%]: 1,16-2,75). A RP de adenomas entre pacientes com 50 anos ou mais foi 2,41 vezes maior do que a daqueles com mais de 50 anos (IC95%: 1,43-4,06). Conclusão Os dados obtidos estão de acordo com os critérios internacionais de qualidade em colonoscopia. Mais estudos são necessários para avaliar as taxas de detecção de adenoma na população brasileira.

Computed Tomography Colonography as a Sensible Option for Colorectal Cancer Screening: Evidence Based on Metanalysis / Colonografia por tomografia computadorizada como uma opção sensível para o rastreamento do câncer colorretal: Evidências baseadas em metanálise

Abstract Objective This metanalysis aimed to evaluate the sensitivity and specificity of computed tomography colonography in colorectal polyp detection. Methods A literature search was performed in the PubMed and Web of Science databases. Results A total of 1,872 patients (males 57.2%, females 42.8%) aged 49 to 82 years old (mean age 59.7 ± 5.3 years) were included in this metanalysis. The estimated sensitivity of computed tomography colonography was 88.4% (46.3-95.7%, coefficient of variation [CV]=28.5%) and the estimated specificity was 73.6% (47.4-100.0%, CV=37.5%). For lesions up to 9mm, the sensitivity was 82.5% (62.0-99.9%, CV =25.1%) and the specificity was 79.2% (32.0-98.0%, CV=22.9%). For lesions>9mm, the sensitivity was 90.2% (64.0-100.0%, CV=7.4%) and the specificity was 94.7% (80.0-100.0%, CV=6.2%). No statistically significant differences in sensitivity according to the size of the lesion were found (p=0.0958); however, the specificity was higher for lesions>9mm (p<0.0001). Conclusions Most of the studies analyzed in the present work were conducted before 2010, which is about a decade after computed tomography colonography started being indicated as a screening method by European and American guidelines. Therefore, more studies aimed at analyzing the technique after further technological advancements are necessary, which could lead to the development of more modern devices.

Resumo Objetivo Esta meta-análise teve como objetivo avaliar a sensibilidade e especificidade da colonografia por tomografia computadorizada na detecção de pólipos colorretais. Métodos Foi realizada uma pesquisa bibliográfica nas bases de dados da PubMed e da Web of Science. Resultados Um total de 1.872 pacientes, 57,2% homens e 42,8% mulheres, com idades entre 49 a 82 anos de idade (média de 59,7 ± 5,3 anos) foram incluídos nesta meta análise. A sensibilidade da colonografia por tomografia computadorizada foi estimada em 88,4% (46,3-95,7%; coeficiente de variância [CV]=28,5%) e a especificidade em 73,6% (47,4%-100,0%; CV=37,5%). Para lesões de até 9mm, a sensibilidade foi de 82,5% (62,0-99,9%; CV=25,1%) e a especificidade de 79,2% (32,0-98,0%; CV=22,9%). Para lesõesmaiores que 9mm, a sensibilidade foi de 90,2% (64,0-100,0%; CV=7,4%) e a especificidade de 94,7% (80,0-100,0%; CV=6,2%). Não houve diferença estatisticamente significante entre as sensibilidades por tamanho da lesão (p=0,0958), porém a especificidade foi maior em lesões acima de 9mm (p<0,0001). Conclusão A maioria dos estudos analisados no presente trabalho foi realizada antes de 2010, cerca de uma década depois que a colonografia por tomografia computadorizada passou a ser indicada como método de triagem pelas diretrizes europeias e americanas. Portanto, são necessários mais estudos com o objetivo de analisar a técnica apósmaiores avanços tecnológicos, o que poderia levar ao desenvolvimento de dispositivos mais modernos.

Investigación formativa para el diseño e implementación de una estrategia para aumentar el rastreo de cáncer colorrectal en el ámbito laboral en Argentina / Formative research for the design and implementation of a strategy to increase colorectal cancer screening in the workplace in Argentina / Pesquisa formativa para a estruturação e implementação de uma estratégia para aumentar o rastreamento do câncer colorretal no local de trabalho na Argentina

Resumen: El ámbito laboral tiene un gran potencial para difundir información e implementar actividades de promoción de la salud, como la prevención y detección temprana del cáncer. Debido al desafío de implementar intervenciones sanitarias en este ámbito, se necesitan investigaciones formativas para adecuar el diseño y la implementación de las estrategias para que sean exitosas. Con el objetivo de informar el diseño e implementación de la intervención, para mejorar la tasa de adherencia al tamizaje con el test de sangre oculta en materia fecal, en un ámbito laboral en Argentina, se realizó una investigación formativa para identificar potenciales barreras y facilitadores. La investigación formativa siguió un diseño metodológico cualitativo. Se realizaron entrevistas con 10 responsables de áreas clave de la institución en que se desarrolló el estudio y 8 grupos focales con trabajadores mayores de 50 años. Se identificaron desafíos para la implementación de la intervención en el nivel institucional, como la dispersión geográfica de los trabajadores y la complejidad del organigrama de la institución, y en el nivel de la población objetivo, como el bajo conocimiento del cáncer colorrectal y de los test diagnósticos, así como la baja percepción de riesgo. Entre los facilitadores se destacaron la aceptabilidad de la intervención, además de la disponibilidad de recursos humanos y materiales para llevar adelante la intervención, como canales de comunicación institucional para la diseminación de información, así como la logística para la distribución de kits diagnósticos. La investigación formativa permitió relevar recursos e identificar potenciales barreras que informaron el diseño y la implementación de la intervención.

Abstract: The workplace has great potential to disseminate information and implement health promotion activities such as cancer prevention and early detection. Due to the challenges of deploying health interventions in this setting, formative studies are needed to adjust the design and implementation of successful strategies. To inform the intervention's design and implementation and improve the adherence rate to screening with fecal occult blood test in a workplace in Argentina, a formative study was conducted to identify potential barriers and facilitators. The formative study adopted a qualitative methodological design. Interviews were held with 10 individuals in charge of key areas in the institution where the main study was conducted, besides 8 focus groups with workers over 50 years of age. Challenges were identified at the institutional level for the intervention's implementation, such as workers' geographic dispersion and the complexity of the institution's flowchart, as well as at the population level, such as low knowledge about colorectal cancer and diagnostic tests and low risk perception. The facilitators featured the intervention's acceptability and the availability of human and material resources to proceed with the intervention, such as institutional communications channels for disseminating the information and logistics for distribution of diagnostic kits. The formative study allowed identifying resources and potential barriers that informed the intervention's design and implementation.

Resumo: O local de trabalho possui grande potencial para divulgar informação e implementar atividades de promoção da saúde, como a prevenção e detecção precoce do câncer. Frente ao desafio de implementar ações sanitárias naquele ambiente, são necessárias pesquisas formativas para adequar a estruturação e a implementação das estratégias para que sejam bem-sucedidas. Com o objetivo de subsidiar a concepção e a implementação da ação, visando melhorar a taxa de aderência ao screening com o teste de sangue oculto nas fezes no ambiente de trabalho na Argentina, foi desenvolvida uma pesquisa formativa para identificar potenciais barreiras e facilitadores. A pesquisa formativa seguiu um formato metodológico qualitativo. Foram realizadas entrevistas com 10 gerentes de áreas chaves da entidade onde foi desenvolvido o estudo e 8 grupos focais, com trabalhadores acima de 50 anos de idade. Foram identificados alguns desafios para a implementação de uma ação em nível institucional, como a dispersão geográfica dos trabalhadores e a complexidade do organograma da entidade, e em termos de população objetiva, como o baixo conhecimento a respeito do câncer colorretal e dos testes diagnósticos, além da baixa percepção de risco. Entre os facilitadores, destacaram-se a aceitabilidade da ação e a disponibilidade de recursos humanos e materiais para levar a cabo a ação, como canais de comunicação institucional, para a divulgação da informação e a logística, para a distribuição dos kits diagnósticos. A pesquisa formativa revelou recursos e identificou potenciais barreiras, ajudando na estruturação e implementação da ação.

Rendimiento del antígeno carcinoembrionario como prueba diagnóstica del cancer colorrectal / Effectiveness of carcinoembryonic antigen to diagnose colorectal cancer / Desempenho do antígeno carcinogênico embrionário como teste diagnóstico do câncer colorretal

Resumen: Introducción: el antígeno carcinoembrionario (CEA) es un marcador tumoral de seguimiento y no una prueba de tamizaje y diagnóstico en cáncer colorrectal (CCR). Sin embargo, en la práctica clínica habitual se continúa solicitando con fines de diagnóstico inicial. Objetivo: evaluar el rendimiento del CEA para el diagnóstico de CCR en el Hospital Maciel y en la Cooperativa Médica de Florida, en el período 2000-2019. Material y método: se trata de un estudio prospectivo de evaluación del CEA como prueba diagnóstica del CCR. Los criterios de inclusión fueron: 1) videocolonoscopía total en los usuarios sin CCR y videocolonoscopía total o parcial para aquellos con CCR y la confirmación histológica de adenocarcinoma; 2) contar con determinación de CEA dentro de los 30 días previos o posteriores a la videocolonoscopía, y 3) para la estadificación, el informe anatomopatológico de la pieza quirúrgica y la confirmación histológica de metástasis a distancia. El número de casos incluidos se determinó por un mínimo de diez casos en cada celda de la tabla de contingencia. Resultados: se analizaron 211 casos. El análisis general determinó una sensibilidad de 33,6%, especificidad 70,4%, valor predictivo positivo (VPP) 69,1%, valor predictivo negativo (VPN) 35%, exactitud 45,9%. Para el estadio II, sensibilidad 18,8%, especificidad 70,4%, VPP 30%, VPN 56,2%, exactitud 49,5%. Estadio III: sensibilidad 31,6%, especificidad 70,4%, VPP 36,4%, VPN 65,8%, exactitud 56,8%. Estadio IV: sensibilidad 65%, especificidad 70,4%, VPP 55,3%, VPN 78,1%, exactitud 68,4%. Conclusiones: el CEA como prueba de confirmación diagnóstica del CCR muestra un bajo rendimiento, siendo aun menor en estadios precoces de la enfermedad.

Summary: Introduction: carcinoembryonic antigen (CEA) is a tumor marker used for follow up rather than a screening and diagnostic test for colorectal cancer (CCR). However, it continues to be requested in the regular clinical practice for initial diagnosis. Objective: to evaluate the effectiveness of CEA to diagnose colorectal cancer at Maciel Hospital and Cooperativa Medica de Florida Hospital from 2000 to 2019. Method: prospective study to evaluate CEA as a diagnostic test for colorectal cancer. The following inclusion criteria were used: 1) total videocolonoscopy in all users without CLC and total or partial videocolonoscopy for those with CRC and histologic confirmation of adenocarcinoma; 2) CEA determination within 30 days before or after videocolonoscopy and 3) for the purpose of staging, pathology report of the surgical piece and histological confirmation of distant metastases. The number of cases included was defined by a 10-case minimum in each cell of the contingency table. Results: 211 cases were analysed. The general analysis revealed 33.6% sensitivity, 70.4% specificity, VPP 69.1%, VPN 35%, accuracy 45.9%. In the case of staging II, sensitivity was 18.8%, specificity 70.4%, VPP 30%, VPN 56.2%, accuracy 49.5%. In the case of staging III, sensitivity 31.6%, specificity 70.4%, VPP 36.4%, VPN 65.8%, accuracy 56.8%. In the case of staging IV, sensitivity 65%, specificity 70.4%, VPP 55.3%, VPN 78.1%, accuracy 68.4%. Conclusions: CEA evidences low effectiveness to diagnose colorectal cancer, and it is still less effective in early stages of the disease.

Resumo: Introdução: o antígeno carcinogênico embrionário (CEA) é um marcador tumoral de acompanhamento e não um teste de rastreamento e diagnóstico em câncer colorretal (CRC). No entanto, na prática clínica de rotina, continua a ser solicitado nos diagnósticos iniciais. Objetivo: avaliar o desempenho do CEA no diagnóstico de câncer colorretal nos Hospitais Maciel de Montevidéu e da Cooperativa Médica de Florida, no período 2000-2019. Material e método: este é um estudo prospectivo avaliando o CEA como teste diagnóstico para câncer colorretal. Os critérios de inclusão foram: 1) videocolonoscopia total em usuários sem CCR e videocolonoscopia total ou parcial naqueles com CCR e confirmação histológica de adenocarcinoma; 2) determinação do CEA 30 dias antes ou após a videocolonoscopia e 3) estadiamento, laudo anatomopatológico da peça cirúrgica e confirmação histológica de metástases à distância. O número de casos incluídos foi determinado por um mínimo de 10 casos em cada célula da tabela de contingência. Resultados: foram analisados 211 casos. A análise geral determinou uma sensibilidade de 33,6%, especificidade 70,4%, VPP 69,1%, VPN 35%, precisão 45,9%. Para o estágio II, sensibilidade 18,8%, especificidade 70,4%, PPV 30%, NPV 56,2%, precisão 49,5%. Estágio III, sensibilidade 31,6%, especificidade 70,4%, PPV 36,4%, NPV 65,8%, precisão 56,8%. Estágio IV, sensibilidade 65%, especificidade 70,4%, PPV 55,3%, NPV 78,1%, precisão 68,4%. Conclusões: o CEA como teste de confirmação diagnóstica do câncer colorretal apresenta baixo desempenho, sendo ainda menor nos estágios iniciais da doença.