Comparison of 18F-NaF PET/CT with Other Imaging Methods in the Detection of Bone Metastases in Patients with Medullary Thyroid Cancer: a Report of a Series of 31 Cases / 대한핵의학회잡지

Purpose@#To compare the 18F-NaF PET/CT studies (18F-NaF) with other imaging methods in the detection of skeletal metastases (SM) in patients with medullary thyroid cancer (MTC). @*Methods@#We retrospectively analyzed 31 patients with MTC who performed 18F-NaF to assess SM. The results of the 18F-NaF were compared with other imaging methods performed for metastasis detection: 99Tc-MDP bone scan (BS), magnetic resonance imaging (MRI), contrast-enhanced CT (CT), and 68Ga-Dotatate and 18F-FDG PET/CT studies. A qualitative analysis comparing the 18F-NaF findings with the ones of the other methods was performed, and the results were classified as superior (>), equal (=), and inferior ( BS and in 3 188F-NaF = BS), 1 performed 18F-FDG (18F-NaF >18F-FDG), 4 performed 18Ga-Dotatate (in 2 18F-NaF >18Ga-Dotatate and in 2 18F-NaF = 18Ga-Dotatate), 20 performed CT of at least one body segment (in 15 18F-NaF = CT and in 5 18F-NaF > CT), and 16 performed MRI of at least one body segment, and in all of them, the 18F-NaF was equal to the MRI. Beside this, the 18F-NaF detected SM in body segments not routinely scanned in MRI and CT. @*Conclusion@#In patients with MTC, the 18F-NaF seems to be equal or superior to other imaging modalities in the detection of SM and allows the analysis of the whole skeletal in a single study.

Intramastoid Phosphaturic Mesenchymal Tumor Causing Hypophosphatemic Osteomalacia Detected on ⁶⁸Ga-DOTATATE PET/CT But Not on (99m)Tc-Sestamibi and ¹⁸F-FDG Scans / 대한핵의학회잡지

⁶⁸Ga-DOTATATE uptake in mesenchymal tumors causing hypophosphatemic osteomalacia has been recently described. Herein, we present a case of ⁶⁸Ga-DOTATATE uptake in an intramastoid phosphaturic mesenchymal tumor that had not been depicted in previous (99m)Tc-Sestamibi and ¹⁸F-FDG scans. The lesion was surgically removed and the phosphorus level increased to the normal range.

Intramastoid Phosphaturic Mesenchymal Tumor Causing Hypophosphatemic Osteomalacia Detected on ⁶⁸Ga-DOTATATE PET/CT But Not on (99m)Tc-Sestamibi and ¹⁸F-FDG Scans / 대한핵의학회잡지

⁶⁸Ga-DOTATATE uptake in mesenchymal tumors causing hypophosphatemic osteomalacia has been recently described. Herein, we present a case of ⁶⁸Ga-DOTATATE uptake in an intramastoid phosphaturic mesenchymal tumor that had not been depicted in previous (99m)Tc-Sestamibi and ¹⁸F-FDG scans. The lesion was surgically removed and the phosphorus level increased to the normal range.

Bone and Calcified Soft Tissue Metastases of Medullary Thyroid Carcinoma Better Characterized on ¹⁸F-Fluoride PET/CT than on ⁶⁸Ga-Dotatate PET/CT / 대한핵의학회잡지

Herein, we report a case of a 19-year-old man with multiple endocrine neoplasia type 2B (MEN2B) and medullary thyroid carcinoma (MTC) diagnosed when he was 12 years of age. The patient had previously undergone total thyroidectomy, cervical radiotherapy, and chemotherapy. He progressed with known bone, pulmonary, and lymph node metastases and was scanned with ¹⁸F-fluoride (¹⁸F-NaF) and ⁶⁸Ga-dotatate whole-body positron emission tomography/computed tomography (PET/CT) for metastatic disease monitoring.We found that the MTC bone metastases and soft tissue calcified metastases were better characterized on ¹⁸F-NaF PET/CT than on ⁶⁸Ga-dotatate PET/CT. This case illustrates that the ¹⁸F-NaF PET/CT could be helpful not only to the detection of bone metastases but also to the detection of calcified soft tissue metastases in patients with MTC.

Bone and Calcified Soft Tissue Metastases of Medullary Thyroid Carcinoma Better Characterized on ¹⁸F-Fluoride PET/CT than on ⁶⁸Ga-Dotatate PET/CT / 대한핵의학회잡지

Herein, we report a case of a 19-year-old man with multiple endocrine neoplasia type 2B (MEN2B) and medullary thyroid carcinoma (MTC) diagnosed when he was 12 years of age. The patient had previously undergone total thyroidectomy, cervical radiotherapy, and chemotherapy. He progressed with known bone, pulmonary, and lymph node metastases and was scanned with ¹⁸F-fluoride (¹⁸F-NaF) and ⁶⁸Ga-dotatate whole-body positron emission tomography/computed tomography (PET/CT) for metastatic disease monitoring.We found that the MTC bone metastases and soft tissue calcified metastases were better characterized on ¹⁸F-NaF PET/CT than on ⁶⁸Ga-dotatate PET/CT. This case illustrates that the ¹⁸F-NaF PET/CT could be helpful not only to the detection of bone metastases but also to the detection of calcified soft tissue metastases in patients with MTC.