Clinical performance of calcitonin and procalcitonin Elecsys^® immunoassays in patients with medullary thyroid carcinoma

Abstract

ObjectivesMedullary thyroid carcinoma (MTC) is caused by a malignant transformation in the parafollicular C-cells of the thyroid, where calcitonin (CT) is released. Nowadays, CT is the main tumor marker used in the diagnosis and follow-up of MTC patients. Nonetheless, procalcitonin (PCT) has recently been proposed as a useful complementary/alternative biomarker in MTC. Our aims were to investigate the diagnostic performance of CT and PCT and their combination in the differential diagnosis between active and inactive MTC and between MTC and non-MTC thyroid diseases, respectively.MethodsSerum samples were collected from 16 patients with active (i.e. primary tumour before surgery or post-surgical recurrent disease) and 23 with inactive (i.e. complete remission) MTC, 125 patients with non-MTC benign thyroid disease and 62 patients with non-MTC thyroid cancers, respectively. Elecsys® CT and PCT measurements were simultaneously performed on the Cobas e601 platform (Roche Diagnostics, Rotkreutz, Switzerland).ResultsBoth CT and PCT median values in active MTC (94 pmol/L and 1.17 ng/mL, respectively) were significantly higher compared with inactive MTC (0.28 and 0.06) and either benign (0.37 and 0.06) or malignant (0.28 and 0.06) non-MTC. Undetectable PCT was found in five non-MTC patients with false positive CT results.ConclusionsElecsys® PCT assay is a highly sensitive and specific alternative MTC marker. At the very least it appears useful in patients with positive CT results as negative PCT values securely exclude active MTC. The availability of both markers on the same automated platform facilitates reflex or reflective strategies to refine the laboratory diagnosis.

Diagnostic Utility of Procalcitonin for Sporadic Medullary Thyroid Carcinoma in Patients with Nodular Disease and Mild or Moderate Hypercalcitoninemia

“…In our study, 5/9 patients without MTC and with Ctn between 20 and 50 ng/ml also had pro-Ctn > 0.1 ng/ml. In contrast, none of the patients without MTC with these Ctn concentrations had elevated pro-Ctn in the series of Giovanella et al [8][9][10] and Censi et al [5].…”

“…On the other hand, we did not have patients without MTC with Ctn ≥ 50 pg/ml and we do not know whether the specificity of pro-Ctn would also be high in these cases. In the series of Giovanella et al [8][9][10] in which pro-Ctn provided specificity close to 100 %, subjects without MTC had Ctn < 50 pg/ml. The same was observed in the study by Censi et al [5] in which all patients without MTC exhibited Ctn < 30 ng/ml and 94.3 % had < 20 ng/ml.…”

Clinical diagnostic value of American College of Radiology thyroid imaging report and data system in different kinds of thyroid nodules

“…The findings of this study might provide a reference for using ACR TI-RADS for newly diagnosed thyroid nodule patients to distinguish malignant nodules, benign nodules, PTC and MTC based on ultrasound data. For patients with highly-suspected MTC based on the results from ACR TI-RADS, CT assay was recommended as it is considered to be a sensitive and specific marker for the diagnosis of MTC [ 31 ]. Using of ACR TI-RADS might also help reduce the unnecessary biopsies in FNA, and decrease the waste of medical resources and the psychological burden to patients.…”

Molecular Imaging and Theragnostics of Thyroid Cancers

“…However, it is not sensitive enough for diagnostic purposes or early assessment following initial surgery [ 106 ]. Procalcitonin, the precursor of calcitonin, shows even superior results compared to calcitonin in the management of MTC [ 107 , 108 , 109 ].…”