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Cytologic specimens categorized as atypical demonstrate cytologic and architectural alterations that are greater than reactive atypia, but less than that of suspicious for malignancy. It is not trivial to repeat pancreatic FNAs diagnosed as atypical as there are a number of individuals involved and use of expensive equipment makes the resource utilization and costs of operative biopsy even greater. The appropriate course of action is dependent on a multidisciplinary review, the functional status of the patient, and the wishes of the patient after clinical consultation [30]. An atypical interpretation on cytology may require additional diagnostic tests such as loss of immunohistochemical staining for the Dpc4/SMAD4 suppressor gene and detection of mutant KRAS that may contribute to management decisions when imaging is suspicious for adenocarcinoma. Ancillary tests such as fluorescent in situ hybridization (FISH) and next-generation sequencing have shown promise in improving diagnostic sensitivity for the detection of malignancy [39, 40]. The related malignancy risk of the atypical category for EUS-FNAs of solid pancreatic masses is 25–100% (mean 58%) [41–43].