RESUMEN
The PathfinderTG biomarker panel is useful in the evaluation of pancreatic cysts that have clinical features suspicious for malignancy, but its utility in classifying fine-needle aspiration biopsies from small pancreatic cystic lesions is yet to be proven. We used morphology to classify 20 pancreatic cyst cytology aspirates, all of which met radiographic criteria for close observation. Cases were cytologically classified as consistent with pseudocyst, serous cystadenoma, or mucinous neoplasm with low-grade, intermediate-grade, or high-grade dysplasia and analyzed for carcinoembryonic antigen. Redpath Integrated Pathology Inc. rendered diagnoses of nonmucinous (reactive/indolent or serous) or mucinous (low-risk or at risk) cyst on the basis of results of the PathfinderTG panel (KRAS mutations, DNA content, and loss of heterozygosity at microsatellites linked to tumor suppressor genes). Cytologic and commercial laboratory diagnoses were concordant in only 7 (35%) cases. Seven cysts classified as mucinous with low-grade dysplasia by cytology were interpreted as nonmucinous on the basis of the PathfinderTG panel, 2 of which were resected mucinous cysts. Two pancreatitis-related pseudocysts were misdiagnosed as low-risk mucinous cysts; 1 mucinous cyst with low-grade dysplasia was considered at risk for neoplastic progression using the PathfinderTG panel. Only 1 cyst misclassified as pseudocyst by cytology, but low-risk mucinous cyst by molecular analysis, proved to be a mucinous cystic neoplasm with low-grade dysplasia after surgical resection. We conclude that the PathfinderTG panel may aid the classification of pancreatic lesions, but is often inaccurate and should not replace cytologic evaluation of these lesions.
Asunto(s)
Biomarcadores de Tumor/metabolismo , Cistadenoma Seroso/clasificación , Tumores Neuroendocrinos/clasificación , Quiste Pancreático/clasificación , Neoplasias Pancreáticas/clasificación , Seudoquiste Pancreático/clasificación , Adulto , Anciano , Desequilibrio Alélico , Cistadenoma Seroso/genética , Cistadenoma Seroso/metabolismo , ADN de Neoplasias/análisis , Diagnóstico Diferencial , Biopsia por Aspiración con Aguja Fina Guiada por Ultrasonido Endoscópico , Femenino , Humanos , Masculino , Repeticiones de Microsatélite/genética , Persona de Mediana Edad , Mucinas/metabolismo , Tumores Neuroendocrinos/genética , Tumores Neuroendocrinos/metabolismo , Quiste Pancreático/genética , Quiste Pancreático/metabolismo , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/metabolismo , Seudoquiste Pancreático/genética , Seudoquiste Pancreático/metabolismo , Estudios Prospectivos , Proteínas Proto-Oncogénicas/genética , Proteínas Proto-Oncogénicas p21(ras) , Proteínas ras/genéticaRESUMEN
Syncytiotrophoblastic knots or syncytial knots are aggregates of syncytial nuclei at the surface of terminal villi. In the term placenta, most syncytial knots are thought to be artifacts from tangential sectioning while the minority are syncytial sprouts, bridges, or apoptotic knots. Syncytial knots are consistently present, increasing with increasing gestational age, and can be used to evaluate villous maturity. Increased syncytial knots are associated with conditions of uteroplacental malperfusion and are important in placental examination. Although 30% of terminal villi with syncytial knots at term are often reported, no reference values have been developed for the percentage of villi with syncytial knots at different gestational ages. We counted the percentage of chorionic villi with syncytial knots at different gestational ages from 20 to 40 weeks using cases with no history of malperfusion or clinical conditions known to be associated with malperfusion. We provide normal reference data for the average percentage of syncytial knots for gestational ages ranging from 20 to 40 weeks. There was a significant positive correlation of gestational age with percentage of villi with syncytial knots. Term placentas (37-40 weeks) showed an average of 28% syncytial knots. A drop-off to a mean of 22.5% was noted at 36 weeks; at 26 to 33 weeks, syncytial knots varied from 10.8% to 14.7%; between 20 and 25 weeks, syncytial knots ranged between 5.2% and 9.l%. These reference data can facilitate histologic assessment of normal placental maturation as well as evaluation of placental morphology in placental malperfusion.
