MEDULLARY THYROID CARCINOMA (MTC) with REMARKABLE CALCIFICATIONS

Various patterns of calcifications may be seen in thyroid cancers  on ultrasonography  (USG)  of thyroid. Coarse calcifications seen in medullary thyroid carcinoma (MTC) are generally associated with posterior shadowing  on thyroid ultrasound.

 We briefly report this case  of MTC with an emphasis on its radiological features.

A  45-year-old  post-menopausal  female presented with  a goiter  (8  cm  ×  7  cm)  of  ten years duration. History was uneventful otherwise. Thyroid function tests were: free T3-2.20 pg/ml  (ref.  range: 1.71-  3.71), free T4-1.18  ng/100ml (ref. range: 0.7-1.48) and TSH-1.42 µIU/ml (ref. range: 0.35-4.94)  respectively. Subsequently,  thyroid  ultrasound revealed prominent  calcifications and increasedvascularity  (Figure 1), (Figure 2).

Computed Tomography (CT) scan  of neck showed large (80 mm × 78 mm) well defined, calcified mass lesion in the left lobe of the thyroid (Figure  3).  Fine  needle aspiration biopsy  (FNAB) confirmed evidence of MTC. A highly elevated calcitonin (20,000  pg/ml) (ref. range: < 5 pg/ml) was consistent with the diagnosis of  MTC.

MTC  may be associated with dense, irregular foci  of calcifications which  are in contrast with  homogeneous calcifications of other thyroid  tumors.  MTC,  first described by Hazard et al. in 1959, has become the focus of increasing clinical and experimental investigations.

However,  in thyroid carcinomas,  ultrasonographic evidence of an  abundance of calcifications may be  rarely seen nowadays due to improved health awareness and earlier diagnosis. To conclude, in an asymptomatic patient with long  standing goiter, coarse macrocalcifications in imaging findings should make the physician vigilant in ruling out MTC.