Thyroid adenolipoma: a case report

Comprehensive guidance on the diagnosis and management of primary mesenchymal tumours of the thyroid gland

Most primary thyroid tumours are of epithelial origin. Primary thyroid mesenchymal tumours are rare but are being increasingly detected. A vast majority of thyroid mesenchymal tumours occur between the fourth and seventh decades of life, presenting as progressively enlarging thyroid nodules that often yield non-diagnostic results or spindle cells on fine needle aspiration biopsy. Surgery is the preferred mode of treatment, with adjuvant chemoradiotherapy used for malignant thyroid mesenchymal tumours. Benign thyroid mesenchymal tumours have excellent prognosis, whereas the outcome of malignant thyroid mesenchymal tumours is variable. Each thyroid mesenchymal tumour is characterised by its unique histopathology and immunohistochemistry. Because of the rarity and aggressive nature of malignant thyroid mesenchymal tumours, a multidisciplinary team-based approach should ideally be used in the management of these tumours. Comprehensive guidelines on the management of thyroid mesenchymal tumours are currently lacking. In this Review, we provide a detailed description of thyroid mesenchymal tumours, their clinical characteristics and tumour behaviour, and provide recommendations for the optimal management of these tumours.

Lipoma of the Neck

BACKGROUND:

Lipomas are benign formations with the mesenchymal origin, which are found in the head and neck region in a very small percentage of cases. In these cases, they usually occur in the posterior neck and usually grow very slowly without causing complaints. However, when they cover the front of the neck, it is necessary to confirm the adipose origin of a tumour and to exclude the connection with the thyroid gland. Although in principle, lipomas are benign, there are three more unfavourable possibilities of 1) malignancy of lipomas, 2) the occurrence of de novo liposarcomas or 3) the association of lipomas with other tumours, such as retinoblastoma.

CASE REPORT:

We present a 74-year-old woman with a painless subcutaneous formation in the neck. A Fine Needle Aspiration Biopsy (FNA) was performed, with the conclusion of the cytological result for lipoma. Surgical removal was planned under general anaesthesia.

CONCLUSION:

Usually, lipomas do not require surgery, but when they engage muscles they become indicative of surgical treatment.

Phantom Nodules Detected by Ultrasound Examination of the Neck: The Possibility of Ectopic Cervical Thymic Tissue in Adults

Purpose

The aim of this study was to investigate the ultrasound characteristics and clinical significance of slightly hyperechoic lesions, referred to as phantom nodules, in the perithyroidal area in patients.

Materials and Methods

A total of 128 patients who underwent thyroidectomy with central neck lymph node dissection at Kuma Hospital in Hyogo, Japan were included in the study. We detected 16 phantom nodules during preoperative ultrasound examinations, defined as slightly hyperechoic masses located in the perithyroidal areas, in 13 of these 128 patients (10.2%; mean age: 55.6 years, range: 36–75 years).

Results

All phantom nodules were located in the caudal region of the thyroid gland, and the mean maximum dimension was 7.2 mm. 12 of the 16 nodules were round or oval, while the remaining 4 were fusiform and molded by the surrounding tissue. All nodules were well-defined, solid, homogeneous, hyperechoic masses. No speckled echo pattern, internal linear echo, or vascular flow signal was observed. All 4 nodules subjected to histological examination were composed of ectopic thymic tissue. In 2 of these 4, the parenchyma was severely involuted and almost entirely replaced by adipose tissue.

Conclusion

To the best of our knowledge, this is the first report wherein some of the detected hyperechoic perithyroidal masses were composed of ectopic thymic tissue, and some were primarily composed of adipose tissue that completely replaced involuted ectopic thymic tissue. The results of the study suggest that these so-called phantom nodules are clinically insignificant and do not require fine needle aspiration cytology or further investigation.