Thresholds of Basal- and Calcium-Stimulated Calcitonin for Diagnosis of Thyroid Malignancy

Horm Metab Res. 2021 Dec;53(12):779-786. doi: 10.1055/a-1661-4420. Epub 2021 Oct 22.


Since medullary thyroid carcinoma is an aggressive cancer, it is important to have an early detection based on stimulated calcitonin (CT), especially when basal-CT is slightly elevated. The objective of this work was to set specific thresholds for basal-CT- and calcium-stimulated calcitonin for prediction of thyroid malignancy in female population. The study included 2 groups: group A-women with elevated basal-CT (>9.82 pg/ml) and group B-women with normal basal-CT (control group). After calcium stimulation test precise protocol, histopathological reports of those that required surgery were correlated with both basal and stimulated calcitonin. The best basal and stimulated calcitonin cut-offs for distinguishing female patients with medullary thyroid carcinoma or C-Cell-hyperplasia from other pathologies or normal cases were: 12.9 pg/ml, respectively 285.25 pg/ml. For basal-CT above 30 pg/ml, malignancy was diagnosed in 9/9 patients (100%): 9 MTC. For stimulated calcitonin above 300 pg/ml, malignancy was diagnosed in 17/21 patients (80.95%): 12 MTC and 5 papillary thyroid carcinomas. The smallest nodule that proved to be medullary thyroid carcinoma had only 0.56/0.34/0.44 cm on ultrasound, with no other sonographic suspicious criteria. In conclusion, we have identified in Romanian female population basal and stimulated calcitonin thresholds to discriminate medullary thyroid carcinoma or C-Cell-hyperplasia from other cases. We recommend thyroid surgery in all women with stimulated calcitonin above 285 pg/ml. Further studies on larger groups are necessary to establish and confirm male and female cut-offs for early diagnosis of medullary thyroid carcinoma, and interestingly, maybe for macro-papillary thyroid carcinomas alike. The calcium administration has minimum side-effects, but continuous cardiac monitoring is required.

MeSH terms

  • Adult
  • Aged
  • Biomarkers, Tumor / blood*
  • Calcitonin / blood*
  • Calcium / administration & dosage*
  • Calcium / blood
  • Carcinoma, Neuroendocrine / blood
  • Carcinoma, Neuroendocrine / diagnosis*
  • Female
  • Humans
  • Longitudinal Studies
  • Middle Aged
  • Prospective Studies
  • Thyroid Neoplasms / blood
  • Thyroid Neoplasms / diagnosis*
  • Young Adult


  • Biomarkers, Tumor
  • Calcitonin
  • Calcium

Supplementary concepts

  • Thyroid cancer, medullary