Case 3
A 70-year-old female was found to have incidental enlargement of the
thyroid gland on a routine outpatient visit. Thyroid ultrasound showed
multiple heterogeneous nodules in the right and left lobes and isthmus.
No neck adenopathy was seen. Thyroid function tests were normal (TSH
0.73 mIU/L, free T4 1.25 ng//dL), and the patient was asymptomatic. Fine
needle aspiration of the two largest thyroid nodules was done, and
pathology showed scattered highly atypical epithelioid cells suspicious
for carcinoma. The patient underwent total elective thyroidectomy for a
definitive diagnosis. Pathology showed large pleomorphic B-cells in
small vascular channels in both thyroid lobes. Cells were positive for
CD10, CD5, BCL-6, and partially positive for MUM1. BCL-2 was negative.
No primary thyroid malignancy was found. Staging PET/CT and MRI brain
were negative for systemic involvement. CSF analysis was deferred given
the lack of clinical and radiological evidence of CNS involvement. The
patient continues to be monitored off chemotherapy with serial imaging
and remains disease-free.