Rare Neural Crest Tumor in Teleost Species: Neuroblastoma in a Spotted Pike-Characin (Boulengerella maculata)
Abstract
Olfactory neuroblastoma (ONB) is rarely diagnosed in teleosts.1 Clinical signs in affected fish vary depending on severity, environmental pressures, and dependence on olfactory processes.1-3 One Boulengerella maculata (spotted pike-characin), managed in a captive collection for seven years, developed a small unilateral pink growth associated with the right nare. The growth eventually extended through both nares after five months. Spotted pike-characin are a species of piscivorous fish that rely on visual acuity when hunting prey, and the rapidly-growing bilateral tumor would have impeded vision if left untreated.4,5 The fish was managed for ten months using only surgical debulking, topical liquid nitrogen, and occasional nonsteroidal anti-inflammatory medications as needed. During that time, diagnosis proved challenging due to superimposed inflammation, cellular inconsistencies within the mass, and a lack of proven immunohistochemical stains (IHC) or other diagnostic stains in fish.6,7 Using tumor location and appearance, histopathology, advanced imaging, and immunohistochemistry, the ultimate diagnosis confirmed ONB, or esthesioblastoma. Though long-term prognosis is poor due to the locally aggressive nature of this type of neuroectodermal neoplasm,6 hunting strategy of the affected species may dictate quality of life as appetite, body condition, and behavior remained largely unchanged in this animal until time of euthanasia.
Acknowledgements
The authors wish to thank the Vancouver Aquarium for financial support of this project as well as the aquarists and Animal Health team for maintaining a focus on quality of life for each animal in their care while advancing our understanding of rare afflictions in captive populations.
* Presenting author
+ Student presenter
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