Clinical History:
A 68-year-old woman presented with a small, hard thyroid lump. Over six weeks, the mass rapidly enlarged, causing laryngeal stridor and esophageal obstruction. No lymphadenopathy or splenomegaly was noted.

Pathology:
The specimen includes the larynx, thyroid, upper trachea, and esophagus. The enlarged left thyroid lobe, and to a lesser extent the right, is replaced by homogeneous pale tumor tissue. The tumor compresses the larynx and esophagus. Histology confirmed lymphoblastic lymphoma of the thyroid. Due to its rarity, anaplastic carcinoma and secondary lymphoma spread must be excluded.

Further Information:
Primary thyroid lymphoma is rare but important to consider in thyroid masses. Most are non-Hodgkin lymphomas; lymphoblastic lymphoma is aggressive and usually seen in children. The main known risk factor is chronic autoimmune (Hashimoto’s) thyroiditis, present in about 50% of cases.

Over 90% of patients present with a rapidly enlarging goitre causing compression of trachea, esophagus, and neck vessels, resulting in symptoms like stridor, hoarseness, dysphagia, and neck pain. Systemic ‘B-symptoms’ may include night sweats, fever, and weight loss.

Diagnosis requires an ultrasound with fine needle aspiration or biopsy. Cytology and immunohistochemistry are essential to differentiate lymphoma from Hashimoto’s thyroiditis or carcinoma.