Colorectal Cancer Diagnostic Methods: The Present and Future.

To meet the needs of the colorectal cancer (CRC) patient population, colorectal cancer screening is continuously updated. The most significant advice is to start CRC screening exams at age 45 for people at average risk for CRC. CRC testing is divided into two categories: stool-based tests and visual inspections. High-sensitivity guaiac-based fecal occult blood testing, fecal immunochemical testing, and multitarget stool DNA testing are stool-based assays. Colon capsule endoscopy and flexible sigmoidoscopy are visualization examinations. There have been arguments about the importance of these tests in detecting and managing precursor lesions because of the lack of validation of screening results. Recent advancements in artificial intelligence and genetics have prompted the creation of newer diagnostic tests, which require validation in diverse populations and cohorts. In this article, we have discussed the present and emerging diagnostic tests.

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

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

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

CEA DNA vaccine induces special cellular and humoral immune response to a carcinoembryonic antigen in mice / 中国癌症杂志

Purpose:To identify the expression of the DNA v accine in mice muscles and detect its ability to induce special cellular and hum oral immune response to carcinoembryonic antigens. Methods:Using cloning technique,the cDNA fragments of CEA gene and mouse co-stimulatory molecule IL-2 gene were constructed into the mammali an co-expression plasmid vector pIRES.Tongue muscle of mice were injected with our plasmid. The expression of CEA molecules in muscle was identified by immunoh istochemitry technique .The humoral responses were detected by ELISA technique, the special celluar immuse responses were detected by CTL and NK cytotoxity assa y. Results:We identified that our plasmids can express the CEA and IL-2 molecules in muscles of mice.CEA-antibody and IL-4 molecules appear in blood serum of mice,CTL activities and NK cytotoxity were much stronger in immun ized mice. Conclusions:The constructed mammalian co-expression plasmid pI RES-CEA , pIRES-IL-2,pIRES-CEA- IL-2 can express CEA and IL-2 molecules i n muscles and can generate cellular and humoral immunological responses to CEA p ositive carcinoma.