Acute tetraparesis in a labrador retriever with suspected ectopic insulinoma and paraneoplastic polyneuropathy

Abstract

Summary: This case report describes a 10‐year‐old, male, neutered labrador retriever that was presented with acute non‐ambulatory tetraparesis, later diagnosed with an ectopic insulinoma and paraneoplastic polyneuropathy. Clinical evaluation revealed severe hypoglycaemia, generalised neuromuscular signs and electromyography findings were consistent with a polyneuropathy. Imaging identified a contrast‐enhancing mass near the ileocecal junction, additional lesions in the liver and enlarged lymph nodes. Surgical excision of the mass, adjacent lymph node and liver biopsies revealed a metastatic neuroendocrine carcinoma. Post‐operative care included glucose monitoring, corticosteroid therapy and recumbency care management. The diagnosis of paraneoplastic polyneuropathy was supported by exclusion of other differentials and clinical response to treatment. The patient showed improvement over the following weeks on steroid therapy, regaining full ambulation and marked improvement of neurological deficits. This case highlights the importance of considering insulinoma and its paraneoplastic complications in dogs presenting with neuromuscular symptoms and hypoglycaemia, even in the absence of a pancreatic mass.