Unusual metastasis of papillary thyroid cancer to the pancreas, liver, and diaphragm: a case report with review of literature

BACKGROUND: Papillary thyroid cancer (PTC) is the most common form of well-differentiated endocrine malignancy. Distant metastases of PTC are rare and usually occur in the bones, lungs, and thoracic lymph nodes despite the common locoregional metastases to the lymph nodes of the neck. The metastasis of PTC to the pancreas is extremely rare. Here, we present a patient with PTC that had simultaneously metastasized to the pancreas, liver, and diaphragm. CASE PRESENTATION: A 47-year-old male patient suffering from mild abdominal pain for 2 months was admitted to our hospital. The ultrasound (US) and computed tomography (CT) scan of the abdomen revealed a pancreatic space-occupying lesion and pancreatic duct dilatation, and the patient underwent exploratory laparotomy. Intraoperative examination identified a hard mass (approximately 4.0 cm × 3.0 cm) in the body and tail of the pancreas and a mass (1.5 cm in diameter) in the diaphragm. Three light masses were also noted on the surface of his liver. The patient underwent radical distal pancreatectomy, splenectomy, diaphragm, and liver mass resection. After surgery, the pathological report revealed that the masses resected from the pancreas, liver, and diaphragm were PTC metastases. Then, the patient had a thyroid US and an endoscopic US-guided fine needle aspiration biopsy of the thyroid mass. Pathology showed papillary cancer. Subsequently, the patient received a complete thyroidectomy, a cervical lymphadenectomy, bilateral parotidectomy, and bilateral submandibular gland resection. CONCLUSIONS: Aggressive surgeries, such as pancreaticoduodenectomy (PD), should be considered for selected patients with metastatic diseases from PTC to alleviate the symptoms and prolong their survival.