Primary Thyroid Diffuse Large B-Cell Lymphoma: Clinical Features, Treatment Outcomes and Literature Review — A Brief Report

Background: Primary thyroid lymphoma (PTL) is a rare extranodal malignancy accounting for 1%–5% of all thyroid neoplasms, with diffuse large B-cell lymphoma (DLBCL) being the most common and aggressive subtype. Due to its low incidence, clinical data remain limited. This study aims to describe the clinical features, diagnostic approaches, treatment and outcomes of primary thyroid DLBCL in a single-center case series. Methods: We retrospectively enrolled four consecutive patients with histopathologically verified primary thyroid DLBCL who received treatment at our institution between 2021 and 2026. All relevant clinical data were extracted from archived electronic medical records. No statistical comparative analyses were performed given the limited sample size. Results: The cohort comprised four females, with a mean age of 73.5 years (range, 50–88 years). All patients presented with a rapidly enlarging painless neck mass, and two (50%) exhibited compressive symptoms. Elevated thyroid autoantibodies (TPO-Ab and/or TG-Ab) were detected in three patients (75%), indicating underlying Hashimoto’s thyroiditis. Diagnostic procedures varied among individuals: fine-needle aspiration cytology (FNAC) and/or core-needle biopsy (CNB), partial thyroidectomy were applied for pathological confirmation. All cases were classified as DLBCL. One patient received R-CHOP immunochemotherapy, one received Pola-R-CHP, and two opted for observation management. Conclusion: This case series provides descriptive real-world observations of primary thyroid DLBCL among elderly Chinese with underlying Hashimoto’s thyroiditis. Findings from this small cohort cannot be generalized. Immunochemotherapy regimens including R-CHOP and Pola-R-CHP may be considered within individualized multidisciplinary strategies; further large-scale studies are required to validate therapeutic performance.