biostudies-literatureUnknown81(12)Ueda KHere, we describe the clinical and histopathological characteristics of a malignant peripheral nerve sheath tumor (MPNST) extending from the dorsal subcutis to the periphery of the spine in a female guinea pig aged 3 years 7 months. The patient presented with pleural and blood-like pericardial effusion and died. The tumor had invaded the spine and the surrounding muscles and had grown in hypercellular and hypocellular arrangements of round, broad-spindle, and elongated-spindle cells. We observed a fascicular growth pattern, nuclear palisading, and perivascular accumulations of cells that responded positively to anti-S100, sox10, and CD56 antibodies. This is the first report of a MPSNT in a guinea pig.The Journal of veterinary medical science1859-1862https://www.ebi.ac.uk/biostudies/studies/S-EPMC6943309biostudies-literatureA case of a malignant peripheral nerve sheath tumor in a guinea pig.PMC6943309Ueda KUeda AOzaki KfalseA case of a malignant peripheral nerve sheath tumor in a guinea pig.Here, we describe the clinical and histopathological characteristics of a malignant peripheral nerve sheath tumor (MPNST) extending from the dorsal subcutis to the periphery of the spine in a female guinea pig aged 3 years 7 months. The patient presented with pleural and blood-like pericardial effusion and died. The tumor had invaded the spine and the surrounding muscles and had grown in hypercellular and hypocellular arrangements of round, broad-spindle, and elongated-spindle cells. We observed a fascicular growth pattern, nuclear palisading, and perivascular accumulations of cells that responded positively to anti-S100, sox10, and CD56 antibodies. This is the first report of a MPSNT in a guinea pig.2019-01-01T00:00:00Z2019 Dec2024-02-15T21:48:54.839Z2020-05-22T07:28:04ZS-EPMC69433093164552110.1292/jvms.19-0464