Expert consensus of the Spanish Society of Pathology and the Spanish Society of Medical Oncology on the determination of biomarkers in pancreatic and biliary tract cancer / Consenso de Expertos de la Sociedad Española de Patología y la Sociedad Española de Oncología Médica sobre la determinación de biomarcadores en el cáncer de páncreas y vías biliares

Pancreatic cancer and biliary tract cancer have a poor prognosis. In recent years, the development of new diagnostic techniques has enabled the identification of the main genetic alterations involved in the development of these tumours. Multiple studies have assessed the ability to predict response to treatment of certain biomarkers, such as BRCA in pancreatic cancer, IDH1 or FGFR2 in biliary tract cancer and microsatellite instability or NTRK fusions in an agnostic tumour fashion. In this consensus, a group of experts selected by the Spanish Society of Medical Oncology (SEOM) and the Spanish Society of Pathology (SEAP) reviewed the role played by these mutations in the process of carcinogenesis and their clinical implications. Based on their results, a series of recommendations are made to optimize the determination of these biomarkers and thus help standardize the diagnosis and treatment of these tumours.

El cáncer de páncreas y el de vías biliares son tumores de mal pronóstico. En los últimos años, el desarrollo de nuevas técnicas diagnósticas de biología molecular ha permitido conocer las principales alteraciones génicas implicadas en el desarrollo de estos tumores. Múltiples estudios han evaluado el carácter predictivo de respuesta a tratamiento de determinados biomarcadores, como BRCA en cáncer de páncreas, IDH1 y FGFR2 en tumores de vía biliar; y la inestabilidad de microsatélites y las fusiones de NTRK, para predecir la respuesta al tratamiento. En este consenso, un grupo de expertos seleccionado por la Sociedad Española de Oncología Médica (SEOM) y la Sociedad Española de Anatomía Patológica (SEAP) ha revisado el papel que desempeñan estas mutaciones en el proceso de carcinogénesis y sus implicaciones clínicas. Como resultado, en este artículo se proponen una serie de recomendaciones para optimizar la determinación de estos biomarcadores, con el fin de fomentar la estandarización en el diagnóstico y el tratamiento de estos tumores.(AU)

Pathological features and diagnosis of intraductal papillary mucinous neoplasm of the pancreas.

Intraductal papillary mucinous neoplasm (IPMN) of the pancreas is a noninvasive epithelial neoplasm of mucin-producing cells arising in the main duct (MD) and/or branch ducts (BD) of the pancreas. Involved ducts are dilated and filled with neoplastic papillae and mucus in variable intensity. IPMN lacks ovarian-type stroma, unlike mucinous cystic neoplasm, and is defined as a grossly visible entity (≥ 5 mm), unlike pancreatic intraepithelial neoplasm. With the use of high-resolution imaging techniques, very small IPMNs are increasingly being identified. Most IPMNs are solitary and located in the pancreatic head, although 20%-40% are multifocal. Macroscopic classification in MD type, BD type and mixed or combined type reflects biological differences with important prognostic and preoperative clinical management implications. Based on cytoarchitectural atypia, IPMN is classified into low-grade, intermediate-grade and high-grade dysplasia. Based on histological features and mucin (MUC) immunophenotype, IPMNs are classified into gastric, intestinal, pancreatobiliary and oncocytic types. These different phenotypes can be observed together, with the IPMN classified according to the predominant type. Two pathways have been suggested: gastric phenotype corresponds to less aggressive uncommitted cells (MUC1 -, MUC2 -, MUC5AC +, MUC6 +) with the capacity to evolve to intestinal phenotype (intestinal pathway) (MUC1 -, MUC2 +, MUC5AC +, MUC6 - or weak +) or pancreatobiliary /oncocytic phenotypes (pyloropancreatic pathway) (MUC1 +, MUC 2-, MUC5AC +, MUC 6 +) becoming more aggressive. Prognosis of IPMN is excellent but critically worsens when invasive carcinoma arises (about 40% of IPMNs), except in some cases of minimal invasion. The clinical challenge is to establish which IPMNs should be removed because of their higher risk of developing invasive cancer. Once resected, they must be extensively sampled or, much better, submitted in its entirety for microscopic study to completely rule out associated invasive carcinoma.