Clinical Nuclear Medicine最新文献

A comparative evaluation using both 18 F-FDG-PET/CT and 68 Ga-FAPI-04 PET/CT in primary staging of a treatment-naïve anterior mediastinal seminoma is illustrated in this report. A 30-year-old man presented with elevated human chorionic gonadotropin levels and biopsy-proven seminoma of the anterior mediastinum. The investigation was performed for primary staging, considering that both tracers may show uptake in the germ cell tumors in the anterior mediastinum, and the potential role of 68 Ga-FAPI-04 PET/CT in treatment-naïve mediastinal seminoma would be examined. The germ cell tumors comprise 1%-4% of mediastinal tumors, and seminomas are less frequent than non-seminomatous tumors.

Pheochromocytomas are rare catecholamine-secreting tumors arising from the adrenal medulla, often presenting with episodic hypertension, palpitations, and diaphoresis. Meanwhile, undifferentiated carcinoma of the uterine corpus is an aggressive and poorly differentiated endometrial malignancy with a high propensity for metastasis and poor prognosis. The incidental detection of such an aggressive malignancy in a patient undergoing evaluation for pheochromocytoma is exceedingly rare and poses significant diagnostic and therapeutic challenges. Here, we present a case of a 63-year-old woman who was being evaluated for right pheochromocytoma and underwent 131 I-MIBG scan for the same, which led to incidental detection of synchronous uterine carcinoma.

Von Hippel-Lindau (VHL) disease is a rare, autosomal dominant, multisystem cancer syndrome. A variety of benign and malignant tumors can develop in VHL, including cranial and spinal hemangioblastomas, retinoblastoma, endolymphatic sac tumor, pheochromocytoma, renal cell carcinoma, pancreatic neuroendocrine tumors, and renal, pancreatic, and genital cysts. Here we present a 57-year-old woman who was diagnosed with VHL and, in the same 68 Ga-DOTATATE PET/CT, exhibits all these components of the syndrome: pheochromocytoma, pancreatic neuroendocrine tumor, pancreatic cysts, renal cysts, liver hemangioma, and hemangioblastoma in the medulla oblongata.

We presented the imaging findings of 18 F-FDG and 68 Ga-HER2 affibody PET/CT in a 52-year-old woman with HER2-positive accessory breast cancer in the right axilla. 18 F-FDG and HER2 PET/CT showed avid uptake of multiple axillary lesions. HER2 PET/CT identified extensive bone metastases with intense uptake, while the ⁹⁹ᵐTc-MDP whole bone scan was negative, and only a few bone lesions with mild tracer uptake were detected by 18 F-FDG PET/CT. Following 6 cycles of the TCbHP regimen, the axillary lesions markedly reduced. This case demonstrates that HER2 PET/CT enables more sensitive detection of HER2-positive lesions, thereby allowing for precise staging and guiding HER2-targeted therapy.

PSMA-targeted radioligand therapies with 177 Lu-PSMA-617 have shown promising response rates with favorable toxicity in patients with metastasized castration-resistant prostate cancer. We report a case of a 72-year-old man with metastatic castration-resistant prostate cancer having comorbidities of DM, HTN, and end-stage renal disease (ESRD) on regular hemodialysis. The patient received 2 doses of 7.4GBq of 177 Lu-PSMA-617, 6 weeks apart. There was complete resolution of prior 68 Ga-PSMA avid lesions, a significant decrease in serum PSA level, and symptomatic response after therapy. We suggest that patients with ESRD on dialysis can be safely treated with 177 Lu-PSMA radionuclide therapy.

Follicular dendritic cell sarcoma (FDCS) of the duodenum is extremely rare. We describe the contrast-enhanced CT and FDG PET/CT findings in a case of duodenal FDCS. Contrast-enhanced CT revealed a large, irregular mass originating from the horizontal portion of the duodenum. The mass demonstrated heterogeneous enhancement, with internal areas of low-attenuation necrosis and coarse calcifications. The mass showed significantly increased FDG uptake. The patient underwent surgical resection, and histopathologic examination revealed a spindle cell tumor positive for CD21 and CD35, confirming the diagnosis of FDCS.

A 58-year-old woman presented with disabling bone pain and muscle weakness. Laboratory tests were unremarkable, except for decreased serum phosphate and elevated urine phosphate levels. A 99m Tc-MDP scan revealed multiple sites of bone fractures. Both 18 F-FDG PET/CT and 99m Tc-FAPI-46 scans identified a lesion in the left heel, which was later resected and diagnosed as phosphaturic mesenchymal tumor on pathologic evaluation. This case represents a pioneering experience in utilizing FAPI for detecting the origin of tumor-induced osteomalacia. It underscores the potential utility of various radiopharmaceuticals in the diagnostic workup of these patients.

A 68-year-old man with a history of abdominal aortic aneurysm presented with incidental coronary artery thickening on coronary CT angiography (CCTA). Eight years later, increased thickening was noted on CCTA and cardiac MRI, with PET/CT showing FDG avidity. Serology revealed elevated IgG4 and ESR. High-dose prednisone led to decreased wall thickening and FDG avidity; rituximab was initiated following relapse. This case highlights the challenges of diagnosing IgG4-related coronary arteritis and underscores the essential role of advanced imaging in guiding surveillance and therapy, especially in asymptomatic patients.

Purpose: To evaluate the radioactive distribution patterns of [ 68 Ga]Ga-FAPI-04 in primary hepatocellular carcinoma (HCC).

Methods: Twenty-three primary HCC patients (26 lesions) from a prospective trial (ChiCTR2000039099) underwent both [ 18 F]FDG and [ 68 Ga]Ga-FAPI-04 PET/CT within 1 week. Uptake at tumor margins versus centers was compared.

Results: FAPI-04 uptake was significantly higher at tumor margins than centers (SUVmax, P <0.001; SUVmean, P <0.01). As SUVmax thresholds increased, FAPI volume of interest concentrated at the margins and decreased sharply in the centers.

Conclusions: [ 68 Ga]Ga-FAPI-04 PET/CT demonstrated higher marginal uptake and pronounced central heterogeneity (low-SUV centers) in HCC. Strong peripheral uptake supports the use of FAP-targeted fluorescence-guided surgery and targeted treatment of marginal residual/recurrent disease, while low central uptake may limit FAP-targeted therapy.

Background: Effective surgical management of persistent air leaks (PAL) after thoracic surgery depends on their quick and reliable localization, which has been hitherto limited to the intraoperative water submersion test (iWST). We present a case series of 20 patients examined for PAL using technetium-99m Technegas ventilation SPECT/CT (vSPECT).

Patients and methods: Technegas was prepared and administered according to the manufacturer's instructions using a Cyclomedica TechnegasPlus generator. SPECT projections were acquired on a Siemens Symbia Intevo Bold gamma camera equipped with a low-energy high-resolution (LEHR) collimator. We reviewed patient records, correlating imaging with intraoperative assessment and the subsequent clinical course.

Results: The median age at the time of surgery was 68.5 years. Surgical indications were pulmonary neoplasm (n = 16, lobectomy/segmentectomy), chronic obstructive pulmonary disease (n = 2, lung volume reduction surgery), solitary fibrous tumor of the pleura (n = 1, fissural pleurectomy), and thymoma (n = 1, thymectomy/pericardectomy). In 10/20 cases, vSPECT successfully located PAL subsequently confirmed by iWST. In 4/20 cases, vSPECT located PAL without confirmation by iWST, however, surgical intervention at the site indicated on vSPECT curbed the leak. In 4/20 cases, PALs identified on vSPECT were managed conservatively as thoracic drainage volumes decreased. In 2/20 cases, vSPECT did not display a PAL; in 1 case, a trocar hernia was found responsible, in another case, revision surgery was deferred, and fistulation resolved without intervention.

Conclusions: Technegas ventilation SPECT/CT appears to be a useful and remarkably accurate modality for the assessment of patients with clinical suspicion of PAL.