Prevalence of sporadic medullary thyroid carcinoma: the importance of routine measurement of serum calcitonin in the diagnostic evaluation of thyroid nodules

Abstract

This study demonstrates a surprisingly high prevalence of sporadic forms of medullary thyroid carcinoma in patients with nodular thyroid disease. Such forms of medullary thyroid carcinoma seem to be unrelated to iodine intake and may be pure or mixed with a follicular carcinoma. In these mixed thyroid carcinomas, only the neoplastic follicular pattern was seen on both cytological and histological examination. Routine measurements of serum calcitonin levels should therefore be considered an integral part of the diagnostic evaluation of thyroid nodules. Indeed, increasing the accuracy of diagnosis of medullary thyroid carcinoma encourages the surgeon to perform more radical treatment, thus achieving more frequent normalization of post-operative serum calcitonin levels.

Reference range of serum calcitonin levels in humans: influence of calcitonin assays, sex, age, and cigarette smoking

“…The prevalence of hypercalcitoninemia not due to MTC varies from 0.3 to 4.5% (2)(3)(4)(5)(6)(7)(8)(9). The assay's high cost and lack of specificity (25) has dissuaded health authorities in the USA from adopting systematic testing (1,26).…”

“…It occurs in 5-10% of thyroid tumors (1) and has a prevalence of between 0.3 and 1.37% in nodular thyroid disease (2)(3)(4)(5)(6)(7)(8)(9). Calcitonin (C T ) is a marker for both initial diagnosis and monitoring of patients with residual or recurrent MTC (10,11).…”

“…Serum C T assays are indicated in nodular thyroid patients if there is a family history of MTC, multiple endocrine neoplasia type 2, or non-defined thyroid cancer (1). In Europe, several researchers have recommended the systematic use of serum C T assays in all nodular thyroid patients, in order to identify sporadic MTC as early as possible (2)(3)(4)(5)(7)(8)(9), optimize surgical treatment (12), and obtain better survival (13).…”

Nodular disease and parafollicular C-cell distribution: results from a prospective and retrospective clinico-pathological study on the thyroid isthmus

“…Actually, two diagnostic tools are available for the evaluation of patients with NTD, including those with MTC: FNAC and measurement of human C t concentrations. Previous European studies recruiting large series of patients with NTD (6)(7)(8)(9)(10)(11)(12) demonstrated that it is possible to diagnose MTC earlier with C t screening than FNAC, particularly in patients with nodules smaller than 10 mm (microMTCs). Hence, the ETA has recommended C t screening in all subjects with NTD (13).…”

“…Several studies (6)(7)(8)(9)(10)(11)(12) on sporadic MTC have demonstrated that the earlier the diagnosis the better the prognosis of MTC. C t has been shown to represent a sensitive marker for MTC, leading to the early diagnosis of the neoplasm even when fine needle aspiration cytology (FNAC) discloses benign features (as occurs in nodules smaller than 10 mm).…”