ESOPHAGEAL SQUAMOUS CELL CARCINOMA IN SIX HARBOR SEALS (PHOCA VITULINASPP.)

Abstract

Six cases of esophageal squamous cell carcinoma were identified in six captive adult Pacific (Phoca vitulina richardsii; n = 2) and Atlantic (Phoca vitulina concolor; n = 4) harbor seals. These seals presented with intermittent dysphagia, regurgitation, inappetence, and abnormal posturing. Common clinical pathology findings in these seals included azotemia, hyperproteinemia, hyperglobulinemia, and leukocytosis. Gastrointestinal endoscopy commonly revealed an ulcerated mass near the gastroesophageal junction. Each seal was euthanized (n = 3) due to poor prognosis, subsequently died while undergoing an anesthetic procedure (n = 2), or found dead (n = 1). The diagnosis of squamous cell carcinoma was confirmed via biopsy of esophageal mucosa during endoscopy or histopathologic examination of affected tissues after necropsy. On the basis of clinical and postmortem findings, esophageal squamous cell carcinoma should be considered as a differential diagnosis in aged harbor seals exhibiting clinical signs of regurgitation, decreased appetite or anorexia, vomiting, and/or abnormal posturing.

Pinnipediae

“…In captive CSLs, mammary carcinoma, lymphoma, and laryngeal squamous cell carcinoma are among the most common. Neoplasia is less common in captive harbor and gray seals, though Flower et al (2014) documented esophageal squamous cell carcinoma in six aged harbor seals possibly associated with regurgitation. Uterine leiomyomas can be seen in aged pinnipeds.…”

Giant cell sarcoma managed with forelimb amputation in a harbour seal (Phoca vitulina geronimensis)

“…Most reports of neoplasia in marine mammals are from necropsy data with little information regarding treatments 3 6 7. Where medical treatments are described, they are typically limited to palliative care and have been associated with poor long‐term outcomes 8 9. In domestic veterinary species medical treatment of soft tissue sarcomas include doxorubicin, cyclophosphamide, and vincristine, although use of such therapeutics are uncommon in marine mammals 10 11.…”

Patología comparada de neoplasias en carnívoros salvajes

“…En seis focas (Phoca vitulina spp) fue diagnosticado carcinoma de células escamosas mediante biopsia de la mucosa del esófago durante la endoscopia o al examen histopatológico de los tejidos afectados después de la necropsia. Los signos clínicos que presentaron las seis focas fueron disfagia intermitente, regurgitación, inapetencia, postura anormal, malestar gastrointestinal (Flower et al, 2014).…”