Nasal Tumor With Widespread Cutaneous Metastases in a Golden Retriever

Abstract

An intact, 8-year-old, male Golden Retriever dog was presented for evaluation of a nasal mass and approximately 30 firm, raised, variably ulcerated dermal and subcutaneous masses. Histopathology of both nasal and multiple skin masses revealed multiple nonencapsulated, infiltrative masses comprising clusters, anastomosing trabeculae, and packets of neoplastic, round to ovoid, hyperchromatic cells with marked nuclear molding. Surrounding the neoplastic cells was a marked stromal response in which many of the spindle-shaped cells expressed muscle-specific actin and had ultrastructural features consistent with myofibroblasts. A literature search indicates that this is the first report in a peer-reviewed journal of cutaneous metastasis of a nasal neuroendocrine tumor in any domestic animal species.

What is your diagnosis? Fine‐needle aspirate from a nasal mass in a dog

“…Among the tumors that can arise in the nasal and paranasal cavities in dogs, neuroendocrine carcinoma (NEC) is rarely reported . Cytologically, neuroendocrine tumors often appear as naked nuclei embedded in a background of pale cytoplasm, and distinct cytoplasmic borders are rarely apparent .…”

“…Histopathologically, a poorly differentiated NEC can be difficult to distinguish from other types of neoplasia including, but not limited to, lymphoma, some neuroectodermal tumors, and embryonal rhabdomyosarcoma . These are part of a group sometimes referred to as “small blue round cell tumors.” As indicated above, lymphoma and rhabdomyosarcoma were ruled out based on the immunohistochemical findings.…”

“…In the nasal cavity, specifically, NEC often closely resembles olfactory neuroblastomas (ON; synonymous with esthesioneuroblastoma) as they share many histologic and immunohistochemical features, and are both part of the “small cell carcinoma” group of neoplasms referred to more commonly in human medicine . NECs in the nasal cavity arise from dispersed neuroendocrine cells of endoderm origin, whereas ON are of neuroectoderm origin . The prognosis for canine ON and NEC is similar, and both will ultimately have a poor prognosis over the long term.…”

“…They are both uncommon to rare neoplasms with a relatively small number of cases reported. Both are locally infiltrative and can involve invasion of the brain, and both have the potential for widespread metastases, though it has been rarely reported in ON with a few more individual cases reported for NEC . Longer term control has been achieved using a combination of surgery and radiation with survival times up to 20 months reported in an ON case …”

Peripheral nerve sheath tumor invading the nasal cavities of a 6-year-old female Pointer dog

“…Among the mesenchymal tumors, chondrosarcoma is the most reported (Ogilvie & LaRue 1992;Wilson & Dungworth 2002). Rarely reported tumors are melanoma (Hicks & Fidel 2006), olfactory neuroblastoma (Brosinski et al 2012), neuroendocrine carcinoma (Sako et al 2005;Ninomiya et al 2008;Koehler et al 2012), and lymphosarcoma (Robertson 1998). Nasal tumors are locally aggressive with a tendency to infiltrate the underlying tissues, to extend into the forebrain or to destroy the septum causing a bilateral involvement.…”