Assessment of cytologic differentiation in high-grade pancreatic neuroendocrine neoplasms: A multi-institutional study

作者：Sigel Carlie S; Silva Vitor Werneck Krauss; Reid Michelle D; Chhieng David; Basturk Olca; Sigel Keith M; Daniel Tanisha D; Klimstra David S; Tang Laura H

来源：Cancer Cytopathology, 2018, 126(1): 44-53.

DOI：10.1002/cncy.21934

<jats:sec><jats:title>BACKGROUND</jats:title><jats:p>Well‐differentiated (WD) and poorly differentiated (PD) pancreatic neuroendocrine neoplasms are biologically distinct entities with different therapies and prognoses. WD neoplasms with elevated proliferation (Ki‐67 &gt; 20%) have been shown to have an overlapping histology with PD neuroendocrine carcinomas. This study compared expert cytomorphologic assessments of differentiation in pancreatic neuroendocrine neoplasms in a multi‐institutional study.</jats:p></jats:sec><jats:sec><jats:title>METHODS</jats:title><jats:p>Fine‐needle aspiration specimens from pancreatic neuroendocrine neoplasms (grade 2 [G2] and grade 3 [G3] according to the 2017 World Health Organization classification; n = 72) were diagnosed independently by 3 cytopathologists as WD or PD (poorly differentiated large cell type [PD‐L] or poorly differentiated small cell type [PD‐S]) purely on the basis of cytomorphology. Their diagnoses were compared with a final classification supported by immunohistochemistry (retinoblastoma (RB), death domain‐ associated protein (DAXX), and α thalassemia/mental retardation syndrome X‐linked (ATRX) protein expression), targeted mutation analysis (Memorial Sloan Kettering–Integrated Mutation Profiling of Actionable Cancer Targets), prior history of G1/G2 histology, and consensus.</jats:p></jats:sec><jats:sec><jats:title>RESULTS</jats:title><jats:p>The rate of agreement on differentiation was 38% (15 WD cases and 12 PD cases) for the 70 cases included (55 WD cases [n = 19 G2, n = 31 G3, and n = 5 could not be graded] and 15 PD cases [n = 6 PD‐S, n = 6 PD‐L, and n = 3 PD, not otherwise specified). Two cases could not be classified by the employed methods. PD carcinomas had a higher rate of agreement (10 of 15 [67%]) than WD neoplasms (15 of 55 [27%]). Round nuclei and plasmacytoid cells were associated with agreement for WD cases, whereas apoptosis and angulated nuclei were associated with disagreement. Necrosis was associated with agreement for PD cases.</jats:p></jats:sec><jats:sec><jats:title>CONCLUSIONS</jats:title><jats:p>A purely morphologic approach to the distinction between G2 and G3 pancreatic neuroendocrine neoplasms based on cytology can be challenging, with disagreement found among experienced cytopathologists. <jats:bold><jats:italic>Cancer Cytopathol</jats:italic> 2018;126:44‐53.

• 出版日期2018-1