Publication:

Diagnosis of metachronous papillary thyroid cancer with elevated carcino-embryonic antigen levels in tracking rectal carcinoma

Carcinoembryonic antigen (CEA) is a tumor marker that is mostly used to track patients with colorectal cancer (CRC). CEA is an indirect tumor marker that can be useful in both malignant and benign diseases. We presented the case of a 49-year-old man who had been monitored for a lower rectal adenocarcinoma since 2010. In 2010, he had an abdominoperineal resection. Previously completed both neoadjuvant and adjuvant chemo-radiotherapy. In 2019, he was planned to undergo parastomal hernia (PS) repair, but studies have shown elevated CEA levels. The CEA concentration was 27.6 ng/ml. Although there were no signs of recurrence, positron emission tomography (PET) and computed tomography (PET/CT) revealed considerable uptake in the left lobar thyroid. Papillary thyroid carcinoma (PCT) was found on fine needle aspiration cytology (FNAc). He underwent total thyroidectomy and CEA level reached the baseline after thyroidectomy.