Elevated Level of Serum Carcinoembryonic Antigen (CEA) and Search for a Malignancy: A Case Report

Abstract

Carcinoembryonic antigen (CEA) has been shown to be associated with tumor burden in patients with colorectal cancer. However, it is also elevated to a significant degree in a number of other malignant and non-malignant conditions. We report a case of reversible CEA elevation in a patient using lithium for bipolar disorder.A 58-year-old female with a longstanding smoking history and a past medical history of chronic obstructive pulmonary disease (COPD), bipolar illness, hypothyroidism, and obesity was found to have an elevated CEA level of 11.2 ng/ml (normal level <5 ng/ml) in the workup for postmenopausal bleeding. Her history was not positive for malignancy of colorectum, ovaries, thyroid, or breast. She underwent a large number of imaging and endoscopic studies to evaluate for colorectal, breast, ovarian, and lung cancer; however, it did not reveal any evidence of malignancy. Upon review of her medications, she reported that she had recently started lithium for her bipolar illness. We followed up her CEA level while her dose of lithium was reduced from 450 to 300 mg per day. Her CEA level decreased from 25 mg/dl to 6.1 mg/dl and remained stable over the course of the next eight months.Our case is the first case report that identifies lithium as a potential cause of reversible CEA elevation. The underlying mechanism is yet to be elucidated, but it underscores the importance of investigating the medications as part of the workup.

A Remarkable Case of Elevated Carcinoembryonic Antigen after Surgical Treatment of Rectal Cancer: A Search for its Mysterious Cause

“…In the present case the more commonly known conditions that cause an elevated CEA were excluded: ovarian cancer, pancreatic cancer, gastric cancer and thyroid cancer [3]. In addition, a literature search revealed several case reports presenting rare entities that cause elevated CEA levels, such as head and neck cancer, mucinous adenocarcinoma of the lip, hypothyroidism, a apocrine hidrocystoma and lithium use, but none of these were helpful for our patient [7][8][9][10][11][12]. With elevated CEA levels as high as in our patient, distant or local recurrence of the rectal cancer was on the top of our differential diagnosis list, followed by a second primary tumour.…”

Comparison of chemiluminescent microparticle immunoassay (CMIA) with electrochemiluminescence immunoassay (ECLIA) for Carcinoembryonic antigen (CEA)

“…The CEA cut-off point is below 3.0 ng/mL, grey zone between 5.0 and 10.0 ng/ mL and cancer between 10.0 and 20.0 ng/mL. (3,4) The Cobas ECLIA limit of detection for CEA was 0.2 ng/mL and for Architect CMIA was 0.5 ng/ mL. The difference in the limit of detection could be one of the explanations of result differences in CEA determination using ECLIA and CMIA technology.…”

“…CEA is the most widely used tumor marker for colorectal cancer and is also frequently elevated in a lung, breast, and gastrointestinal tumors (2). Most studies have adopted a CEA cutoff point <3.0 ng/mL for healthy non-smokers, between 3.0 and 5.0 ng/mL for healthy smokers, gray zone for levels between 5.0 and 10.0 ng/mL, cancer for levels between 10.0 and 20.0 ng/mL, and metastasis for levels >20.0 ng/mL (3,4). In colon cancer, CEA is used for prognosis, postsurgery surveillance, and chemotherapy response monitoring (5).…”

Graphene Quantum Dot-Based Electrochemical Immunosensors for Biomedical Applications

“…Carcinoembryonic antigen (CEA) is one of the major tumor markers associated with the diagnosis and controlling of malignant tumors, such as pancreatic, colorectal, lung, liver, breast, and gastric cancers [113][114][115][116][117][118]. It is an oncofetal glycoprotein with a molecular weight of 180-200 kDa [119], which is generally expressed by mucosal cells and overexpressed by various malignancies [120,121]. Elevated level of CEA in human blood (>5 ng mL −1 ) is an indication of cancer cell formation [116].…”