Researchers in the US reported the case of a man aged 64 years with type 2 diabetes mellitus and obesity who was medically evaluated because he wanted to increase his life insurance policy. 

The evaluation showed that he had elevated levels of carcinoembryonic antigen (CEA) but no other symptoms or gastrointestinal complaints.

Imaging techniques showed that he had a nodule in his left thyroid, which had features consistent with medullary carcinoma. Based on this finding, he underwent a thyroidectomy and histopathological analysis confirmed he had medullary thyroid carcinoma (MTC).

Continue Reading

The researchers concluded that this new case underscores the importance of considering MTC in patients with persistently elevated levels of CEA even if they do not have any gastrointestinal symptoms or nodules. The study is published in The American Journal of Medicine.

Read more about the treatment of MTC

CEA is not only a marker for malignancies of the gastrointestinal tract but it can also be elevated in other diseases such as peptic ulcer disease, inflammatory bowel disease, pancreatitis, liver disease, and other epithelial tumors as well as in people who are tobacco users or have started adjuvant chemotherapy.

If case levels are higher than 10 ng/mL, malignancies related to the gastrointestinal tract should be evaluated using colonoscopy, esophagogastroduodenoscopy, and computed tomography. If these come back negative, other rarer malignancies should be considered.

MTC is a rare type of neuroendocrine tumor of the thyroid gland arising from the parafollicular cells, accounting for around 3% to 10% of all thyroid carcinomas. Malignant parafollicular cells secrete high levels of CEA as well as calcitonin, which can help identify the disease. 

If the disease is caught early and is localized, the 5-year survival rate is almost 100%. However, in cases where the disease has metastasized to distant sites, the 5-year survival is reduced to around 38%.


Urquhart SA, Guo R, Alexander GL. Elevated carcinoembryonic antigen as initial presenting sign of medullary thyroid carcinoma. Am J Med. 2023;2:S0002-9343(23)00063-3. doi:10.1016/j.amjmed.2023.01.008