Thyroid Sporadic Goiter with Adult Heterotopic Bone Formation

Table 2

Main morphological characteristics of the 5 thyroidectomy specimens.

Number	Thyroid weight (grams)	Thyroid volume (mm^3)	Number of HBF foci (size, mm)	Number of ossification foci	Thyroid calcifications	Thyroid fibrosis	Thyroid inflammation	Vascular calcifications	Thyroid adipose involution
1	48	93.75	1 (2.5 mm)	0	1	Severe	Moderate	No	Multifocal
2	32	72	27 (2–10 mm)	11	1	Severe	Moderate	No	Multifocal
3	38	51	1 (10)	0	1	Mild	Mild	Intra-, perithyroid	No
4	115	195	2 (1 and 9.5 mm)	14	1	Mild	Moderate	Intra-, perithyroid	No
5	43	180	1 (8 mm)	0	1	Mild	Mild to moderate	Intra-, perithyroid	Multifocal

Cases 3, 4, and 5 showed also reticular and perivascular calcifications in hyperplastic nodules.
Normal parathyroid tissue was seen in the perithyroid adipose tissue in Case 1.