A 79-year-old Taiwanese woman came to the otolaryngologic clinic of our hospital due to an enlarging painless mass over the right neck region in the past 3 months. She denied fever, night sweats, dyspnea, hoarseness, dysphagia, dysphasia, or stridor. On physical examination, the right thyroid lobe was noted to be enlarged and firm. There was a palpable mass in the front of her neck, which moved during swallowing. She had no history of Hashimoto's thyroiditis or cervical irradiation, and her thyroid function test was within the normal range (thyroid-stimulating hormone: 2.01 nIU/mL; free T4: 1.24 ng/dL; thyroglobulin: 1.62 ng/mL; anti-thyroperoxidase: 1.03 IU/mL; and thyroglobulin antibody: 1.81 IU/mL).\nThe patient had received computed tomography (CT) at hospital outside, which revealed a hypodense nodule with minimal enhancement on the right lobe of thyroid gland []. Its size was approximately 4.1 cm × 3.6 cm, with a longitudinal dimension of 4.5 cm. The trachea, vessels, and soft tissues in the right neck were under pressure and displaced toward the left side. She underwent fine-needle aspiration (FNA) at that hospital, and the cytologic results were suspicious of lymphoma.\nIn order to obtain more definite results, this woman was referred to the radiological department of our hospital for core needle biopsy. During core needle biopsy, the neck color Doppler ultrasound showed a large heterogeneous hypoechoic mass with an irregular border in the right lobe of thyroid gland. There were twisted and chaotic intranodular vessels, but no defined calcification, hemorrhage, or necrotic portion was observed within the mass, which exhibited indistinct margins and posterior acoustic enhancement [Figure and ]. The pathology revealed diffuse large B-cell lymphoma (DLBCL). For staging the disease, a fluorodeoxyglucose (FDG) positron emission tomography (PET) scan was performed, revealing high-grade hypermetabolic lymphomatous disease, confined in the right thyroid gland, suggesting PTL Ann Arbor stage I [].\nAfter consulting oncology specialists, she started rituximab-based chemotherapy and received serial sonographic follow-up. After three cycles of rituximab plus bendamustine – rituximab (375 mg/m2) and bendamustine (Innomustine®, 90 mg/m2) by intravenous administration on day 1 were administered every 3 weeks for each cycle – neck color Doppler ultrasound showed a significant reduction of twisted blood flow signals in the PTL but no significant decrease (<25% extent) of the tumor size []. Therefore, chemotherapy regimen was adjusted to rituximab, cyclophosphamide, vincristine, prednisone (R–COP). After three cycles of R–COP, i.e., rituximab (375 mg/m2), cyclophosphamide (750 mg/m2), and vincristine (2 mg/m2) by intravenous administration on day 1 and prednisone (100 mg/m2) by oral administration on day 1–5 were administered every 3 weeks for each cycle, the PTL disappeared on the color Doppler and gray-scale ultrasonography []. The patient was treated with R–COP regimen until complete remission of the disease, confirmed on the following FDG PET-CT and whole-body PET examination [].
A 52-year-old woman presented to our Endocrinology Unit with a growing thyroid mass, which had enlarged so rapidly she had become unable to wear her motorcycle helmet in the weeks prior to her visit. She suffered from Hashimoto’s thyroiditis for which she was taking levothyroxine. There was no history of neck irradiation or family history of thyroid cancer. On examination, there was a large, firm thyroid nodule on the right side of the neck, without palpable cervical lymphadenopathy. TSH was 4.79 μU/mL with FT3 and FT4 within the reference range. Otherwise, there was only a mild thrombocytopenia. Thyroid ultrasonography showed a solid hypoechoic nodule in the right lobe of the gland, with significant internal vascularity and absence of calcifications (Figure ). FNA cytology with rapid on-site evaluation of the material adequacy showed that there were only atypical lymphoid cells with no thyrocytes and the specimens were considered suggestive of a lymphoproliferative disorder but insufficient to make a diagnosis, such that a CNB was scheduled for the following day.\nAfter checking the blood coagulation profile, the patient underwent a CNB, which allowed histological/morphological tissue analysis. This showed that normal thyrocytes were virtually all replaced by homogeneous medium-sized lymphocytes with scanty blue cytoplasm, round nuclei, coarse chromatin, and multiple small nucleoli. There were frequent mitotic figures and scattered macrophages ingesting apoptotic cells, giving to the tissue section the so-called ‘starry sky’ appearance (Fig. ). Overall, these features were consistent with the presence of a thyroid Burkitt’s lymphoma, and further investigations were ordered to confirm the diagnosis and evaluate the disease extent. A CT of chest and abdomen showed the 44x43x87 mm thyroid nodule with left tracheal deviation (Figure ) without other visible masses or lymph nodes. Bone marrow biopsy showed almost 100% lymphoid infiltration, consisting of a population of intermediate-sized blast-like cells, with prominent nucleoli, which were replacing all normal cells. These cells expressed CD10, CD20, and were negative for Bcl2, CD34, and TdT. Altogether these results led us to the final diagnosis of stage IV Burkitt’s lymphoma [].\nThe patient was admitted to our hospital’s Haematology Unit and was successfully treated with 3 cycles of Hyper-CVAD chemotherapy (cyclophosphamide, vincristine, doxorubicin and dexamethasone) completed in five months. The thyroid mass disappeared (Fig. ) and the platelets returned to baseline levels. At 60 months after diagnosis the patient is alive, and remains disease-free at regular follow-up.