Primary Thyroid Lymphomas: A Decade of Clinical Experience through Eight Case Reports

Background: Primary thyroid lymphoma (PTL) is a rare malignancy, accounting for less than 5% of all thyroid cancers and less than 2% of extranodal lymphomas. It typically affects elderly individuals and is often associated with chronic lymphocytic thyroiditis, particularly Hashimoto’s disease. The diagnosis can be challenging due to overlapping clinical and imaging features with other aggressive thyroid malignancies such as anaplastic carcinoma. Objective: This study aims to present and analyze eight cases of primary thyroid lymphoma managed in our department, highlighting the clinical presentations, radiological features, histopathological subtypes, therapeutic approaches, and patient outcomes. Methods: We conducted a retrospective analysis of eight patients diagnosed with PTL over a five-year period. Clinical symptoms, imaging findings (ultrasound and CT scan), histopathological and immunohistochemical results, treatment modalities, and follow-up outcomes were documented. EU-TIRADS classification was used to stratify the ultrasound features of the thyroid lesions. Results: The patients (5 men and 3 women) ranged in age from 45 to 78 years. All presented with a rapidly enlarging neck mass, with compressive symptoms in six cases and systemic B symptoms in three. Two patients had superior vena cava syndrome, and one had Claude Bernard-Horner syndrome. Ultrasound revealed hypoechoic, heterogeneous lesions with irregular margins in all cases, and EU-TIRADS scores ranged from 4 to 5. CT imaging showed large thyroid masses with mediastinal extension in four cases. Histological analysis identified diffuse large B-cell lymphoma (DLBCL) in all eight cases. All patients received R-CHOP chemotherapy, and three received adjunctive radiotherapy. Despite treatment, two patients died due to severe local complications before completing therapy. The remaining six showed good clinical and radiological response with long-term remission in four.