@entity4847 of the gastrointestinal tract: a clinicopathologic study of 2 cases and reappraisal of perineurial cells in XXXX .

@entity808 @entity1 @entity698 @entity5 @entity2281 @entity3670 @entity344 @entity4786 @entity413 @entity2280 @entity4847 @entity356
Soft tissue neoplasms with features of both @entity808 and @entity4847 ( @entity4847 ) have been increasingly recognized in recent years. To date, only a single case of this entity has been documented in the gastrointestinal tract (sigmoid colon). We herein describe 2 new cases of this entity. For comparison, we reevaluated 12 classic @entity344 for the perineurial cell component. The 2 hybrid @entity4847 were detected incidentally in the gastric antrum and the vermiform appendix in a 50-year-old @entity1 and a 17-year-old @entity1 during surgery for @entity356 and @entity698 -like symptoms, respectively. None of the @entity1 had @entity4786 1 or 2. @entity1 were alive with no evidence of recurrence or new @entity5 at 8 and 12 months, respectively. The @entity5 measured 1.2 cm and 1.5 cm in size. Histologically, they showed prominent storiform, lamellar, and fascicular patterns. Notably, both lacked peripheral lymphoid cuffs and the trabecular pattern of @entity344 . Both @entity5 coexpressed protein @entity2281 (>= 80%), @entity2280 (80%), and the perineurial cell markers (20% to 40% of @entity5 cells). The perineurial cell component formed alternating fascicles with @entity2281 -positive cells throughout the @entity5 . Reevaluation of 12 classic @entity344 showed isolated @entity3670 /epithelial membrane antigen-positive cells. However, 4 @entity808 (33%) strongly expressed @entity413 transporter-1 in most of the @entity5 cells indicating its limited specificity in this setting. Compared with @entity344 , @entity2280 expression was stronger and more diffuse in hybrid @entity4847 . We conclude that hybrid @entity4847 are distinct from @entity344 , both histologically and immunohistochemically.
