Endocrine Cancers In Dogs And Cats

Endocrine cancers develop in the body’s hormone-producing glands, including the thyroid, adrenal glands, pancreas, and parathyroid glands. These tumours may produce excess hormones that disrupt normal physiology or grow silently until advanced. Common endocrine tumours in dogs include thyroid carcinoma, insulinoma (pancreatic islet cell tumour), and adrenal tumours (pheochromocytoma, adrenocortical carcinoma).

Thyroid adenomas are frequent but typically benign in cats, while thyroid carcinomas and insulinomas are less common but clinically significant. Because endocrine tumours often behave differently from other cancers, combining hormonal testing with advanced imaging is essential to determine their impact.

Clinical signs vary depending on the gland and the hormone involved:

• Thyroid tumours present as neck swelling, coughing, weight loss, or hyperthyroidism (in cats).
• Adrenal tumours, signs of Cushing’s disease (excess cortisol), Addison’s disease (low cortisol), or episodic collapse with pheochromocytomas.
• Insulinomas, recurrent weakness, tremors, collapse, or seizures caused by low blood sugar.
• Parathyroid tumours, increased thirst and urination, weakness, and calcium imbalances.

Diagnosis typically involves blood and hormone testing, ultrasound, CT or MRI, and tissue sampling. However, because endocrine tumours may metastasise early or be multifocal, conventional imaging can underestimate the extent of the disease.

Endocrine cancers present unique diagnostic challenges, especially when small or metabolically active tumours evade standard imaging. PET-CT adds metabolic insight, showing where a tumour is and how active it is biologically.

The primary advantages include:

• Whole-body staging detects small or hidden metastases in the lungs, liver, or lymph nodes that may be missed on ultrasound or CT.
• Highlights hormonally active tissue, aiding in locating insulinomas, pheochromocytomas, or thyroid carcinomas.
• Maps tumour extent and metastatic spread before thyroidectomy, adrenalectomy, or pancreatic surgery.
• Assesses residual tumour activity after surgery, radiation, or medical therapy.
• Helps differentiate indolent versus aggressive disease, shaping treatment intensity and owner discussions.

Endocrine cancers can be complex to manage due to their dual impact: local tumour growth and systemic hormonal effects. Pet owners struggle to understand these diseases because signs may seem vague or unrelated. PET Theranostics provides vets with the highest level of diagnostic clarity, ensuring that endocrine tumours are not only located but fully staged and functionally assessed. Referrals for a comprehensive PET-CT scan and report are now available. Vets can use the online referral form. Pet owners can contact their primary vet and ask for a referral.