MEIS1::NCOA1 Primitive Spindle Cell Sarcoma of the Kidney : Report of 7 Cases of a Distinctive Clinicopathologic Entity.

ABSTRACT: Primitive sarcomas harboring the MEIS1::NCOA2 gene fusion were originally described in the kidney in 2018, and subsequently reported in other organs. These variably cellular neoplasms feature monomorphic primitive plump spindle cells forming nodules and whorls in addition to nondescript fascicular, solid, and storiform patterns. They lack skeletal muscle differentiation in contrast to the primarily intraosseous rhabdomyosarcomas that harbor the same gene fusion. We describe 7 new primary primitive renal sarcomas with MEIS1::NCOA1 gene fusions. Although their morphology overlaps with that described in MEIS1::NCOA2 renal sarcoma, 3 of the 7 cases contained adipose tissue. The majority had intimately admixed entrapped cystic epithelial elements and demonstrated patchy immunoreactivity for est

SUBMITTER: Argani P 

PROVIDER: S-EPMC12715815 | biostudies-literature | 2025 Jun

REPOSITORIES: biostudies-literature