The Importance of Imaging Procedures in Evaluating Painful Neck Masses: Two Patients with a Painful Internal Jugular Vein Thrombosis

Dear Editor:

Internal jugular vein thrombosis (IJVT) is a rare but potentially life-threatening status, as it can lead to fatal pulmonary embolism. One of its clinical manifestations is a painful anterior neck mass (1). Here, we report two patients with IJVT in whom a painful anterior neck mass initially suggested subacute thyroiditis (SAT).

The first patient was a 68-year-old woman with Graves' disease, in remission after antithyroid drug treatment, who consulted our hospital for right anterior neck pain. Palpation revealed a painful firm 6.5 cm × 4.0 cm nodule on the right side of her neck. It extended from the level of the laryngeal prominence to the supraclavicular region. Since the mass was painful and appeared consistent with an enlarged right thyroid lobe, SAT was considered. Unexpectedly, thyroid function tests indicated she was euthyroid and the serum thyroglobulin (Tg) was normal but the serum C-reactive protein level was high (4.5 mg/dL). Thyroid ultrasonography (US) revealed a diffuse hypoechoic and moderately heterogeneous thyroid gland, consistent with treated Graves' disease, but no features of SAT. US also showed a hypoechoic spindle-shaped mass of 6.3 cm × 2.0 cm in the noncompressible right internal jugular vein (IJV) that was laterally adjacent to the thyroid lobe (see Supplementary Data, available online at www.liebertonline.com/thy). D-dimer (normal range <1.0 μg/mL) was 6.3 μg/mL and fibrinogen (normal range 150–400 mg/dL) was 449 mg/dL. She was hospitalized and diagnosed with IJVT associated with stomach cancer after examinations that included contrast-enhanced computed tomography (CT) and endoscopic biopsy.

The second patient was a 51-year-old woman referred to our hospital because of suspected SAT. She complained of a one-week history of right anterior neck pain and vague right shoulder and brachial discomfort. A painful, firm, 8.0 cm × 4.0 cm nodule was palpable in the region of the right thyroid lobe. Although SAT was suspected, thyroid function tests and serum Tg were normal. As US indicated a hypoechoic thrombus of 7.4 cm × 3.2 cm in the right IJV (see Supplementary Data), and since both D-dimer and fibrinogen were high (6.0 μg/mL and 429 mg/dL, respectively), she was admitted to our hospital. Thrombosis of the IJV and subclavian vein caused by a Pancoast tumor was diagnosed using US, contrast-enhanced CT, and subsequent transbronchial lung biopsy.

Deep vein thrombosis (DVT) occurs most commonly in the lower extremities or pelvis. IJVT is uncommon in the whole DVT because only about 10% of DVT develops in the internal jugular, axillary, and subclavian veins in the upper torso. Pulmonary embolism, a life-threatening complication, occurs with similar frequency in patients with DVT in the lower and upper extremities, at rates of 3%–36% (2). Since the mortality rate of pulmonary embolism is as high as 10%–30%, the early identification and treatment of DVT are mandatory. The location of an upper torso DVT is not important in this regard, as the mortality is similar among thromboses of the subclavian, axillary, and IJV (3).

Central venous catheters and malignant neoplasms are two leading causes of IJVT. Two mechanisms have been suggested for the positive relationship between thrombogenesis and malignant neoplasms. One is the occurrence of a hypercoagulable state in malignancy and the other is venous stasis due to compression or direct tumor invasion of veins (1). Patients 1 and 2 appeared to have the former and latter factors, respectively.

Painful anterior neck masses are usually associated with thyroid-related lesions, such as SAT, acute infectious thyroiditis, or hemorrhage in a thyroid nodule. Other very rare painful neck lesions include cervical lymphadenitis and infected cysts (4). Our two cases were confused with SAT because the palpation findings closely resembled those of SAT, and because initial imaging procedures were not performed. US is an easily available and useful noninvasive method for evaluating such conditions. It is widely accepted that noncompressibility of a normally compressible vein with or without a visible thrombus is definitive proof of IJVT. The sensitivity and specificity of US for IJVT is 78%–100% and 82%–100%, respectively. CT has also been useful for the assessment of IJVT, the main advantage of which is the detection of pulmonary embolism, together with IJVT (2).

In conclusion, we encountered two patients with IJVT whose clinical findings resembled SAT. Imaging modalities such as US and CT are important for the close evaluation of painful neck masses.