Primary Large Diffuse B Cell Lymphoma Presenting as Rapidly Enlarging Thyroid Mass with Compressive Symptoms: A Case Report

Background: Primary thyroid lymphoma are seen occasionally accounting for 5% among thyroid tumors. Commonest of these lymphomas is diffuse large B cell type. Case report: A 66 years old female presented to our Department with rapidly enlarging thyroid mass having difficulty in swallowing as well as breathing. She underwent left hemithyroidectomy 30 years ago for a benign disease. Clinicallly it was a large mass 20 × 20 cm hard inconsistency and clinically attached to sternocleidomastoid muscles with no skin and lymph node involvement. Computed Tomography (CT) scan of neck with contrast showed large ill-defined mass noted arising from the right lobe of the thyroid gland encasing the common carotid with loss of fat planes between the mass and the right jugular vein, sternocleidomastoid, trachea, esophagus suggesting involvement. She underwent incisional biopsy of mass which showed Diffuse Large B Cell Lymphoma (DLBCL). Discussion: Most of thyroid lymphomas originate from B cells. Fine Needle Aspiration Cytology (FNAC) can diagnose 80-85% of cases but definitive diagnosis can be made by biopsy only. Surgery has a limited role in treatment and main modality is chemoradiotherapy. Conclusion: A rapidly enlarged thyroid swelling should be suspected of having lymphoma specially on the background of lymphocytic thyroiditis and multidisciplinary team approach should be used for management.