Unusually aggressive rectal carcinoid metastasizing to larynx, pancreas, adrenal glands, and brain

Rectal carcinoids are slow-growing tumors. They metastasize when their size is more than 2 cm. Common sites of metastasis are the liver, lungs, and bones. Metastases to thyroid, pancreas, kidneys, adrenal glands, pituitary glands, posterior fossa, and spleen are very rare. We present the case of a 79-year-old white man with dysphagia and left vocal cord paralysis from a rapidly growing mass in his neck. Needle biopsy suggested thyroid anaplastic carcinoma, and the patient underwent total laryngectomy, total thyroidectomy, and left radical neck dissection. Pathology showed undifferentiated carcinoid of the larynx. Biopsy of a rectal mass suggested poorly differentiated carcinoma. Postoperatively the patient developed cardiac arrhythmias and died after 5 weeks. Autopsy showed a 5-cm carcinoid of the rectum with extensive vascular invasion extending into the perirectal fat. There was metastatic disease to both lungs, liver, pancreas, both adrenal glands, peritoneum, subcutaneous tissues of thorax and abdomen, ribs, vertebrae, skull, and the leptomeninges of the cerebrum. Rectal carcinoids may present a variable histologic picture. Poorly differentiated tumors can present with widespread metastases and have poor prognosis. Extensive surgery may not improve the survival of patients with this pattern of unusually aggressive carcinoid.