Partial Pancreatectomy

Partial pancreatectomy is recommended when:

• An insulinoma is identified — a small, usually malignant tumor that continuously secretes insulin regardless of blood sugar levels, causing recurrent seizures, weakness, and collapse
• A pancreatic mass is identified on imaging that is suspicious for cancer and appears resectable
• Severe, localized pancreatic abscess or pseudocyst does not respond to medical management and drainage

Medical management of insulinoma (frequent small meals, steroids, diazoxide) can stabilize patients but is not curative; surgery removes the tumor and typically provides months to over a year of improved quality of life. Abdominal CT is used to identify the number and location of lesions before proceeding, since insulinomas are often small and multiple lesions affect surgical planning.

Partial pancreatectomy is performed under general anesthesia with full monitoring. The steps:

• An abdominal incision provides access to the pancreas; the entire organ and surrounding lymph nodes are carefully inspected and palpated for nodules
• The affected segment is isolated and the blood vessels supplying it are ligated (tied off) before the tissue is divided
• Gentle closure of the pancreatic parenchyma (tissue) is performed to reduce leakage of digestive enzymes into the abdomen — a phenomenon called pancreatic leak, which can cause severe local inflammation
• Regional lymph nodes may be removed and submitted for staging if an insulinoma is confirmed
• The abdomen is closed, and the patient transitions to intensive monitoring for blood glucose stability

Pre-surgical preparation for an insulinoma patient focuses on stabilizing blood glucose to prevent a hypoglycemic episode during or immediately after anesthesia:

• Abdominal CT or ultrasound to localize and count the lesions
• Pre-anesthetic bloodwork including blood glucose, insulin-to-glucose ratio, liver values, and complete blood count
• Dextrose (glucose) supplementation via IV fluid during surgery to maintain blood sugar in a safe range
• Withhold food the evening before, but the anesthesia team administers glucose-containing fluids throughout to prevent hypoglycemia during the fast

Patients with pancreatic mass lesions of uncertain type also undergo chest X-rays for metastatic screening before proceeding.

Pancreatectomy patients are hospitalized for two to four days post-operatively. The critical monitoring priorities are:

• Blood glucose: checked every two to four hours in the first day — hypoglycemia from persistent tumor activity or rebound hyperglycemia from traumatized normal tissue can both occur
• Pancreatitis: inflammation of the remaining pancreas is the most common post-operative complication; managed with IV fluids, pain control, and anti-nausea medication
• At home: restricted activity for three weeks; a low-fat, easily digestible diet is often recommended initially; frequent small meals help stabilize glucose while the pancreas heals
• Blood glucose is rechecked at two and four weeks and again at three months; insulin levels are monitored to detect tumor recurrence

Pancreatectomy is a technically demanding procedure with meaningful perioperative risks. The most important are:

• Post-operative pancreatitis: inflammation of the remaining gland causes pain, vomiting, and anorexia; managed medically and usually resolves within a week
• Pancreatic leak: digestive enzyme leakage into the abdomen is uncommon but serious
• Diabetes mellitus: if a large portion of the pancreas is removed, the remaining tissue may not produce sufficient insulin; some dogs develop temporary or permanent diabetes after pancreatectomy
• Tumor recurrence: insulinomas are often malignant, and metastasis to lymph nodes or liver is common; median survival after surgery is typically one to two years, though some dogs do significantly better

Despite these risks, surgery consistently provides the most meaningful improvement in quality of life for insulinoma patients, and it remains the recommended first step in management when the tumor is localized and the patient is otherwise healthy.