Primary neuroblastoma in the skin of an adult shih tzu dog

Rosettes and pseudorosettes in veterinary neuropathology

Rosettes and pseudorosettes are morphologic cell arrangements found in many neuroepithelial neoplasms in human medicine, including embryonal nervous system tumors (neuroblastoma, medulloblastoma, pineoblastoma, and retinoblastoma), non-embryonal nervous system tumors (ependymoma, astrocytoma, oligodendroglioma, and choroid plexus tumors), and other extraneural neuroepithelial neoplasms. Although these structures are also described in neuroepithelial neoplasms of domestic animals, their frequency is still poorly characterized or inconsistently documented in veterinary medicine. Furthermore, rosettes and pseudorosettes need to be interpreted with caution and within a clinical and pathologic context and should not be solely relied upon for diagnostic confirmation of a particular neoplasm. Here, we review the morphologic features and frequency of the most common types of rosettes and pseudorosettes described in neuroepithelial neoplasms of domestic animals, focusing primarily on those occurring in the nervous system and closely associated tissues.

Enteric peripheral neuroblastoma in a calf

An 11-month-old female Japanese Black calf had showed chronic intestinal symptoms. A large mass surrounding the colon wall that was continuous with the colon submucosa was surgically removed. After recurrence and euthanasia, a large mass in the colon region and metastatic masses in the omentum, liver, and lung were revealed at necropsy. Pleomorphic small cells proliferated in the mass and muscular layer of the colon. The cells were positively stained with anti-doublecortin (DCX), PGP9.5, nestin, and neuron specific enolase (NSE). Thus, the diagnosis of peripheral neuroblastoma was made. This is the first report of enteric peripheral neuroblastoma in animals. Also, clear DCX staining signal suggested usefulness of DCX immunohistochemistry to differentiate the neuroblastoma from other small cell tumors in cattle.

Footpad peripheral ganglioneuroblastoma in a dog

BACKGROUND

Peripheral neuroblastic tumours arising from primitive cells of the cranial and spinal ganglia and from sympathetic ganglion cells of the autonomic nervous system include, from most to least differentiated, ganglioneuroma, ganglioneuroblastoma and neuroblastoma. Canine ganglioneuroblastoma has been described in the mediastinum, nasal and oral cavities, as well as in the brain.

OBJECTIVE

To describe the clinical and histopathological findings, treatment and follow-up of a primary cutaneous ganglioneuroblastoma affecting the footpad of a dog.

ANIMAL

An 8-year-old male German shepherd dog, referred for left forelimb lameness and licking of the footpad, showed thickening of the footpad of digit V with a central nodular lesion.

METHODS AND RESULTS

Histopathological and immunohistochemical examination on a surgical skin biopsy specimen showed an infiltrative and highly cellular neoplasm in the deep dermis. The neoplasm was composed of large polyhedral cells with abundant cytoplasm containing Nissl substance that reacted strongly with neuron-specific enolase and neuronal nuclei antigen, spindle cells with indistinct cell borders suggestive of Schwann cells, with a mild S-100 and GFAP immunoreactivity, and rare nests of neuroblasts. The owner agreed to digit amputation. Histologically, a neoplastic multinodular proliferation with morphological findings like those detected in the biopsy was observed, not extended to the surgical margins and without involvement of skeletal bone. No recurrence or metastasis was observed over a period of one year.

CONCLUSIONS AND CLINICAL IMPORTANCE

To the best of the authors' knowledge, this is the first report of a primary cutaneous ganglioneuroblastoma in a dog. Ganglioneuroblastoma should be included in the differential diagnoses of canine footpad neoplastic diseases.