A cerebral primitive neuroectodermal tumor in a squirrel monkey (Saimiri sciureus)

Retroperitoneal extraosseous peripheral primitive neuroectodermal tumor in a Formosan serow: case report and literature review

A 10-y-old female captive Formosan serow (Capricornis swinhoei) was inactive and was azotemic. An autopsy was performed following her death, and multiple irregularly shaped, white-to-gray masses of 0.5-2 cm diameter were noted on both ureters, the left adrenal gland, urinary bladder, and uterus. Microscopically, organs were effaced by a poorly demarcated, highly infiltrative neoplasm, composed of neoplastic round cells arranged in islands, sheets, or nests with occasional rosette formation. The neoplastic cells were small: ≤2 red blood cell (≤ 15 μm) diameter. The neoplastic cells were positive for CD56, CK, FLI-1, and NSE, but negative for desmin, GFAP, melan A, NF, PAX-8, S100, synaptophysin, and vimentin. Therefore, the diagnosis of retroperitoneal extraosseous peripheral primitive neuroectodermal tumor (pPNET) was made. pPNET with FLI-1 expression has not been reported previously in animals, to our knowledge.

Retrobulbar primitive neuroectodermal tumor in a squirrel monkey (Saimiri sciureus)

BACKGROUND

A 2.8-year-old female captive-bred common squirrel monkey (Saimiri sciureus) showed exophthalmos of the right eye, and the eye was surgically enucleated. A tumor mass was found in the eye.

METHODS

Formalin-fixed tumor samples were examined histopathologically and immunohistochemically for diagnosis.

RESULTS

The retrobulbar tumor mass adhered to the sclera and infiltrated the choroid. Histopathologically, tumor cells were pleomorphic, arranged in a sheet pattern, and mimicked primitive neuroectodermal cells. The tumor cells were strongly positive for precursor neuronal cell markers (beta III tubulin, neuron-specific enolase, vimentin, nestin, doublecortin, oligo2, and S-100), but negative for mature cell markers (cytokeratin, neurofilament, and glial fibrillary acidic protein) and a retinoblastoma marker (rhodopsin).

CONCLUSIONS

This is the first reported case for the retrobulbar location of primitive neuroectodermal tumor in non-human primates.

Quantitation of sleep and spinal curvature in an unusually longevous owl monkey (Aotus azarae)

BACKGROUND

A table summarizing the primary literature on 19 species of longevous non-human primates, other than owl monkey, is presented.

METHODS

We prospectively quantitated the sleep of a longevous female owl monkey (Aotus azarae), aged >30 years, longitudinally for 2 years and also evaluated the senility-induced change in spinal curvature.

RESULTS

The mean daily total sleep time (TST) of this monkey ranged between 790 and 1106 minutes, and was markedly higher in comparison with its female progeny (aged 16 years and used as a control) whose daily TST during the same experimental period ranged between 612 and 822 minutes.

CONCLUSIONS

The calculated kyphotic index (KI) of 2.27 for this monkey, compared with the KIs 4.83 and 5.42, for its progeny and female grandprogeny (aged 1 year) respectively, confirmed the prominent spinal curvature.

Cerebral primitive neuroectodermal tumour in a heifer

A primitive neuroectodermal tumour (PNET) replacing the thalamus was discovered in an 18-month-old Prim'Holstein heifer. Microscopical examination of the tumour showed large sheets of densely packed cells with occasional Homer-Wright and perivascular rosettes. Neoplastic cells were small with ill-defined borders, scant cytoplasm and ovoid, irregularly shaped nuclei. Immunolabelling was positive for vimentin and neuron-specific enolase, in agreement with previous reports of PNETs in human beings and animals. This appears to be the first report of cerebral PNET in cattle.

A case of canine primitive neuroectodermal tumor (PNET)

A 2-year and 6 month-old, female, Golden Retriever showed circling behavior and seizure. By magnetic resonance imaging (MRI) examination, a mass was found on the surface of the left cerebral hemisphere, invading to the left temporal muscle. The skull bone between them was destroyed. The dog was euthanized and necropsied. Histologically, the mass contained a lot of undifferentiated anaplastic cells, forming Homer-Wright rosettes and pseudopalisading patterns. Thus, the case was diagnosed as primitive neuroectodermal tumor (PNET).