Primary Thyroid Lymphoma Diagnosed on Rapid Onsite and Cytology: A Rare Case Report

Introduction Rapid on-site evaluation (ROSE) is an essential component of thyroid cytopathology, particularly important in thyroid lymphoma, anaplastic carcinoma, metastasis to avoid unnecessary surgery. Follicular epithelial neoplasms are the most common tumors arising from the thyroid, whereas primary thyroid lymphomas are uncommon, accounting for less than 5% of all thyroid malignancies.Case description A 45-year-old male patient presented to our ENT outpatient department with swelling in the anterior neck for 3 years duration. Non-aspirational needling was done along with rapid on-site evaluation using 1% aq. toluidine blue and was reported as Malignant thyroid neoplasm- possibility of Non-Hodgkin lymphoma (NHL). Cellblock sample also confirmed as B-cell NHL followed by Immunohistochemistry.Discussion Primary thyroid lymphomas (PTL) are uncommon malignant neoplasms. They represent < 5% of all thyroid malignancies and 1-2% of all extra-nodal lymphomas. If diagnosed cytologically, unnecessary surgery can be avoided in thyroid lymphoma. ROSE helps in the rapid diagnosis and sample adequacy. Cellblock can avoid the biopsy procedure used for confirmation and subtyping of lymphoma.