Occlusion of the internal jugular vein in differentiated thyroid carcinoma: Causes and diagnosis

A Comprehensive Review and Insights into the New Entity of Differentiated High-Grade Thyroid Carcinoma

Differentiated high-grade thyroid carcinoma (DHGTC) is a new subset within the spectrum of thyroid malignancies. This review aims to provide a comprehensive overview of DHGTC, focusing on its historical perspective, diagnosis, clinical characteristics, molecular profiles, management, and prognosis. DHGTC demonstrates an intermediate prognosis that falls between well-differentiated thyroid carcinoma and anaplastic thyroid carcinoma. Previously unenumerated, this entity is now recognized for its significant impact. Patients with DHGTC often present at an older age with advanced disease and exhibit aggressive clinical behavior. Molecularly, DHGTC shares similarities with other thyroid malignancies, harboring driver mutations such as BRAFV600E and RAS, along with additional late mutations. The unique behavior and histologic features of DHGTC underscore the necessity of precise classification for prognostication and treatment selection. This highlights the critical importance of accurate diagnosis and recognition by pathologists to enrich future research on this entity further.

Intraluminal extension of papillary thyroid carcinoma into the Internal Jugular Vein; a case report

BACKGROUND

Papillary thyroid carcinoma (PTC), being the most common thyroid malignancy, is a slow-growing tumor and is usually limited to the thyroid. Extra thyroid extension is uncommon; besides, invasion to the vasculature seems to be extremely rare and usually indicates aggressive nature of the disease.

CASE PRESENTATION

We present a case of a 40-year-old lady who referred with a palpable neck mass a month after total thyroidectomy which its histopathologic examination revealed follicular variant of PTC; the same variant as prior thyroidectomy. Preoperative ultrasonography failed to comment on the intravascular component of the mass. Surgical procedure confirmed a mass attaching and infiltrating to the internal jugular vein, which turned out to be persistent disease.

CONCLUSIONS

Awareness of this entity is important for surgeons, oncologists and radiologist as it can influence patient management.

Metastatic renal cell carcinoma to the thyroid with cervicothoracic venous tumor thrombosis

INTRODUCTION

Metastatic renal cell carcinoma (RCC) represents 25%-42% of metastatic thyroid malignancies. Propensity for RCC to demonstrate intravascular extension to the inferior vena cava is well documented. We present an analogous phenomenon of intravascular extension to the internal jugular vein (IJV) from thyroid gland metastasis.

METHODS

A 69-year-old male presented with metastatic RCC of the right thyroid lobe. Imaging demonstrated tumor thrombosis of the ipsilateral IJV, extending inferiorly to the junction of the brachiocephalic, subclavian, and internal jugular veins within the mediastinum.

RESULTS

Surgical excision required control of both the IJV in the neck and mediastinal venous great vessels via sternotomy, prior to subtotal thyroidectomy and venotomy for en bloc resection.

CONCLUSION

This case report describes metastatic RCC to the thyroid gland with cervicothoracic venous tumor thrombosis successfully treated with subtotal thyroidectomy, sternotomy for venotomy and tumor thrombectomy, and preservation of IJV conduit.