Fig. 1Thyroid ultrasonography shows a well-defined hypoechoic mass in the left lobe.
Fig. 2Histologic examination. (A) The greater part of the area is a well-circumscribed lesion without capsulation. (B) Spindle cells show ovoid and slightly pleomorphic nuclei, and the nucleolus are small but distinct. There are also lymphocytes and a few plasma cells and mitosis is not clear. (C) Hemosiderin-loaded histiocytes and small lymphocytes are mixed with haphazardly scattered spindle cells. (D) The trapped residual thyroid follicular cells have no characteristic cytological findings of papillary carcinoma.
Fig. 3Immunohistochemistry. The spindle cells are positive for α-smooth muscle actin (A), but negative for thyroid transcription factor-1 (B), and anaplastic lymphoma kinase (C). (D) A few plasma cells are negative for immunoglobulin G4.
Table 1.Main clinicopathologic findings of thyroid inflammatory myofibroblastic tumors/plasma cell granulomas in the English literature
|
Age (yr)/Gender |
Histology |
Clinical presentation |
HT |
ALK |
Reference |
1 |
70/F |
PCG |
3-cm nodule, difficult breathing |
– |
NA |
- |
2 |
61/F |
PCG |
Symmetric goiter |
– |
NA |
- |
3 |
35/F |
PCG |
3-cm nodule, trachea compression |
– |
NA |
- |
4 |
51/F |
PCG |
5-cm painful nodule |
– |
NA |
- |
5 |
55/F |
PCG |
2.2-cm nodule |
– |
NA |
- |
6 |
65/F |
PCG |
Dyspnea, 5-cm nodule |
+ |
NA |
- |
7 |
29/M |
PCG |
Tiredness, fever, sore throat, painful 8-cm nodule, dysphagia |
– |
NA |
- |
8 |
46/F |
PCG |
Asymptomatic neck mass |
– |
Negative |
- |
9 |
46/M |
PCG |
Goiter with dominant left lobe nodule |
+ |
NA |
- |
10 |
35/F |
PCG |
Rapid thyroid enlargement with tracheal compression |
+ |
NA |
- |
11 |
41/M |
PCG |
Enlarging neck mass, dysphonia, anorexia, weight loss |
+ |
NA |
- |
12 |
50/M |
PCG |
Goiter, feeling of narrowness in the neck |
+ |
NA |
- |
13 |
65/M |
PCG |
Goiter, large painless neck mass; progressively growing neck mass |
– |
Negative |
- |
14 |
44/F |
PCG |
|
+ |
|
|
15 |
55/F |
PCG |
Enlarging goiter |
+ |
NA |
- |
16 |
18/F |
IMT |
3-cm firm nodule right lobe |
– |
Negative |
Trimeche et al. [3] |
17 |
75/F |
IMT |
1.5-cm painless nodule left lobe |
– |
Negative |
Kojima et al. [4] |
18 |
89/F |
PCG |
Large firm irregular mass left lobe |
+ |
NA |
Barber et al. [5] |
19 |
47/F |
PCG |
Subhyoid mass, subtotal thyroidectomy 20 years ago |
+ |
NA |
Cremonini et al. [2] |
20 |
50/F |
IMT |
0.6-cm thyroid mass |
– |
Negative |
Present case |