Adrenocorticotropic hormone-dependent hypercortisolism caused by pancreatic neuroendocrine carcinoma: A thought-provoking but remorseful case of delayed diagnosis

INTRODUCTION AND IMPORTANCE: Definitive diagnosis of functioning neuroendocrine neoplasms (NENs) in the pancreas is challenging. Adrenocorticotropic hormone (ACTH) regulates adrenal cortisol production. Ectopic ACTH secretion by functioning NENs may cause hypercortisolism. PRESENTATION OF CASE: A 62-year-old woman who was receiving medications for hypertension and hyperlipidemia was referred to our hospital because of abnormal blood tests. Diabetes mellitus was initially diagnosed. Dynamic computed tomography and endoscopic ultrasound revealed a 35-mm diameter hypovascular tumor in the distal pancreas and multiple liver metastases. Endoscopic ultrasound-guided fine-needle aspiration resulted in a diagnosis of neuroendocrine carcinoma. The patient developed pancreatic leakage progressing to peritonitis, abscess formation, pleural effusion, and ascites after the fine-needle aspiration biopsy. Her clinical condition deteriorated to a septic state, necessitating emergency surgery comprising distal pancreatectomy, intraperitoneal lavage, and drainage. Wound healing was protracted and accompanied by ongoing high white blood cell counts and neutrophilia. She also developed a gastric ulcer postoperatively. Systematic endocrine investigations were performed because hypercortisolism caused by a functioning NEN was suspected. Eventually, a definitive diagnosis of an ACTH-producing NEN in the pancreas was made. Systemic chemotherapy was proposed; however, the patient and her family opted for palliative treatment only. She died 42 days after the initial diagnosis. CLINICAL DISCUSSION: We here present a patient with ACTH-dependent hypercortisolism attributable to a pancreatic NEN who died of progressive cancer after a delay in definitive diagnosis. CONCLUSION: Detailed investigation, including systematic endocrine examination and functional imaging studies, are important for precise diagnosis of, and appropriate treatment for, NENs.