n-n-dimethyl-n-(18f)fluoromethyl-2-hydroxyethylammonium and Thyroid-Neoplasms

A 67-year-old man was diagnosed with primary hyperparathyroidism and normofunctioning left nodular goiter. Fine-needle aspiration cytology showed thyroid (Thy) 4 (suspicious of malignancy). After first-line imaging proved negative, integrated 18F-choline PET/4D contrast-enhanced CT revealed uptake by the thyroid nodule and by 3 nodules of the left central compartment. Thyroidectomy and lymphadenectomy were performed. Histopathology revealed a collision tumor (ie, 2 histologically distinct tumors occurring at the same anatomic site) composed of both PTC (papillary thyroid carcinoma) and parathyroid carcinoma within the left thyroid nodule. Lymph nodes showed PTC metastases. Primary hyperparathyroidism and calcium levels normalized, and the patient underwent radioiodine therapy.

Topics: Aged; Choline; Humans; Hyperparathyroidism, Primary; Iodine Radioisotopes; Male; Positron Emission Tomography Computed Tomography; Thyroid Neoplasms; Thyroid Nodule

An 85-year-old man with a 2-year history of prostate cancer, treated with radiotherapy and hormonal therapy, presented increased prostatic-specific antigen levels. F-choline PET/CT showed focal prostatic uptake consistent with known local recurrence, increased uptake of 2 hypodense thyroid nodules and of 2 left cervical lymph nodes, suspected as thyroid cancer. Neck ultrasound confirmed the high risk of malignancy, and a guided biopsy (of a thyroid nodule and cervical lymph node) revealed cellular infiltrates thyroid transcription factor-1 (TTF-1) negative and prostatic-specific antigen positive, confirming intrathyroid and cervical lymph node metastases of prostate cancer. PET/CT changed the disease staging. Chemotherapy was initiated.

Topics: Aged, 80 and over; Choline; Humans; Incidental Findings; Male; Positron Emission Tomography Computed Tomography; Prostatic Neoplasms; Thyroid Neoplasms

A 77-year-old woman underwent thyroidectomy and (131)I remnant ablation for tall-cell differentiated cancer (DTC) of the left lobe. Detectable Tg levels (4.1 μg/L) under TSH suppression, with undetectable serum Tg-antibody levels, prompted neck ultrasonography, which revealed a lymph node in the left laterocervical region and in the right retroclavicular region. (18)F-FDG PET/CT showed uptake by the left lymph node. (18)F-choline PET/CT showed increased uptake by both lymph nodes. Histopathology revealed DTC solid metastasis in the left lymph node and solid and cystic metastasis in the right one. (18)F-choline PET/CT can locate virulent DTC recurrence, thereby increasing (18)F-FDG PET/CT information.

Topics: Aged; Choline; Female; Fluorodeoxyglucose F18; Humans; Lymphatic Metastasis; Multimodal Imaging; Positron-Emission Tomography; Radiopharmaceuticals; Thyroid Neoplasms; Tomography, X-Ray Computed

We report a case of thyroid incidentaloma detected by 18F-choline PET/CT. A 66-year-old male patient with a history of prostate cancer underwent a 18F-choline PET/CT for restaging. PET/CT revealed a focal area of increased 18F-choline uptake corresponding to a hypodense nodule in the right lobe of the thyroid. Based on PET/CT findings, the patient underwent a ultrasonography guided fine-needle aspiration biopsy which demonstrated the presence of a benign thyroid nodule.

Topics: Aged; Choline; Humans; Incidental Findings; Male; Multimodal Imaging; Positron-Emission Tomography; Thyroid Neoplasms; Tomography, X-Ray Computed