Follicular thyroid carcinoma (FTC) has metastasis in 10-15%; papillary thyroid carcinoma (PTC) rarely metastasizes. Bone metastasis are rare and can cause pain, fractures and spinal cord compression.
72 year-old male referred to the hospital with lower back pain. Imaging examination revealed lytic lumbar lesions. Thoracic-abdominal-pelvic-CT showed trachea compression by a multinodular right thyroid lobe. Thyroid-US revealed a 35 mm nodule in that lobe FNAC: Bethesda IV. Biopsy of one lytic lesion showed thyroid carcinoma metastasis. Total thyroidectomy was performed histology: PTC. Therapy with 131I took place; post-treatment 131I-scintigraphy revealed low back hyperfixation. During follow-up, he maintained signs of bone metastases, confirmed by FDG-PET-CT. Heunderwent radiotherapy and further 131I treatment. The disease progressed with bone and pulmonar lesions and eventually he lost his mobility. He declined TKI treatment and died 4 years after diagnosis.
59-year-old female referred to the hospital, in 2011, with inferior limb pain. Pelvic-CT revealed lesions around the left iliac bone: biopsy revealed FTC metastasis. A thyroid-US showed a 32 mm left lobe nodule FNAC: Bethesda V. She underwent total thyroidectomy (histology: FTC) and 131I; post-treatment 131I-scintigraphy showed hyperfixation of ileum, sacrum and scapula. Before any further treatment, she died with generalized bone metastatic disease.
76-year-old female (prior history of right hemithyroidectomy in 2014, for benign nodular goiter) sent to neurosurgery in 2018, with occipital headache. Brain-MRI showed lytic lesions of the occipital bone: biopsy revealed FTC metastasis. Thyroid-US showed 2 nodules on the remaining thyroid (18 mm; 7 mm) FNAC: Bethesda IV. Totalization of thyroidectomy was performed histology: NIFTP. She underwent 131I therapy. Post-treatment 131I-scintigraphy revealed hyperfixation of the thyroid bed, occipital bone (confirmed by brain-MRI), right ribs and lung. After another 131I therapy, scintigraphy showed persistent disease. Radiotherapy is on demand.
In 2015, a 82 year-old female was admitted to the hospital with thoracic pain. Thoracic-CT showed a 38 mm pulmonary nodule and sternum lytic lesion (histology compatible with FTC metastasis). ThyroidUS revealed a 22 mm left lobe nodule FNAC: Bethesda VI. Total thyroidectomy took place in 2016 histology: FTC. 131I therapy was proposed. Post-treatment 131I-scintigraphy revealed hyperfixation of the thyroid bed, sternum and lungs, confirmed by thoracic-CT. The patient underwent a second 131I therapy, but the disease progressed. She refused further treatment and died 1 year later.
These cases show rare presentations of differentiated thyroid carcinoma. We must pay attention to ostearticular complains, especially in the presence of thyroid nodules or previous thyroid surgery.
22 May 2021 - 26 May 2021