Pineal parenchymal tumor in a domestic rabbit.

ABSTRACT: An 11-y-old male lionhead rabbit (Oryctolagus cuniculus) was presented with progressive hindlimb weakness and right-sided neurologic deficits, and was subsequently euthanized due to poor prognosis. Autopsy revealed a 1.6 × 1.1 × 1.0-cm, well-circumscribed, extra-axial mass compressing the occipital lobe and affecting both telencephalic hemispheres. Histologic and immunohistochemical analyses demonstrating positivity for synaptophysin and neuron-specific enolase, along with a Ki67 proliferative index of ~20%, were highly suggestive of a high-grade pineal parenchymal tumor (PPT). The tumor was densely cellular with marked atypia and frequent binucleation, and lacked pineocytomatous rosettes-features most consistent with a pineal parenchymal tumor of intermediate differentiation in hum

SUBMITTER: Crakes KR 

PROVIDER: S-EPMC12463860 | biostudies-literature | 2026 Jan

REPOSITORIES: biostudies-literature