Molecular Imaging and Radionuclide Therapy最新文献

Neoplastic infiltration of the omentum is mostly caused by metastatic ovarian, gastric, colon, or pancreatic cancer. Lymphomatous infiltration of the omentum is rare because the omentum lacks a lymphoid component. To date, lymphomatous involvement of the omentum has only been reported in patients with non-Hodgkin lymphoma. Peritoneal lymphomatosis remains a rare presentation of malignant lymphoma characterized by diffuse peritoneal lesions and is frequently accompanied by ascites and mesenteric lesions. In this review, we aimed to illustrate the case of a 72 year old mal patient diagnosed with aggressive large B-cell lymphoma, adressed for initial extension assessment in whom ¹⁸F-fluorodeoxyglucose positron emission tomograph/computed tomography found unusual omental and mesenteric involvement.

Primary liposarcoma of the lung is extremely rare. To date, only 24 cases have been reported in the English literature. Herein, we present a case of well-differentiated pulmonary liposarcoma that was misdiagnosed as teratoma on positron emission tomography/computed tomography (CT) and contrast-enhanced CT. Radical surgery with left superior lobectomy and mediastinal lymph node dissection were performed. The patient experienced recurrence and distant metastases 33 months after surgery. He was alive at the time of writing this report (36 months postoperatively). To our knowledge, this is the first case report of pulmonary well-differentiated liposarcoma.

A Chemoport is frequently utilized in oncological patients for administering chemotherapy. However, inadequate care can lead to various infectious and non-infectious complications. Infection commonly presents as a local infection that can lead to life-threatening septicemia. Early diagnosis and intervention are necessary to reduce morbidity and mortality. We report a patient with breast cancer who underwent ¹⁸F-fluorodeoxyglucose positron (¹⁸F-FDG) positron emission tomography/computed tomography (PET/CT) due to suspicion of metastatic disease. ¹⁸F-FDG-PET/CT revealed pyomyositis involving multiple skeletal muscles and septic emboli in the lungs and identified the chemoport as a possible source of infection. The infection source was confirmed and the patient responded to anti-microbiological therapy.

Objectives: This study aimed to evaluate the potential efficacy of ⁶⁸Ga-fibroblast activation protein inhibitor (FAPi) positron emission tomography/computed tomography (PET/CT) for detecting, staging, and restaging digestive system malignancies that are ¹⁸F-fluorodeoxyglucose (¹⁸F-FDG) negative or show equivocal ¹⁸F-FDG uptake.

Methods: We conducted a prospective analysis of 30 patients with pathologically confirmed primary tumors or metastases of the digestive system. Participants underwent ⁶⁸Ga-FAPi PET/CT and ¹⁸F-FDG PET/CT imaging for staging or restaging purposes within the same week. The efficacy of ⁶⁸Ga-FAPi PET/CT was assessed by comparing its ability to detect lesions and influence disease staging with that of ¹⁸F-FDG PET/CT.

Results: ⁶⁸Ga-FAPi PET/CT imaging was performed in 30 patients with ¹⁸F-FDG-negative or indeterminate lesions. Of the 30 patients, 23 had gastric cancer and 7 had colorectal cancer. Among all patients, histopathological diagnosis of signet ring cell carcinoma was present in 15 (50%) patients. Primary tumor or local recurrence was detected in 19 (63%) patients, lymph node metastasis in 8 (27%) patients, visceral metastasis in 4 (13%) patients, peritoneal metastasis in 14 (47%) patients, and bone metastasis in 3 (10%) patients on ⁶⁸Ga-FAPi PET/CT images. All patients underwent histopathological confirmation on ⁶⁸Ga-FAPi PET/CT images. The disease stage was upgraded in 20 patients (67%) after ⁶⁸Ga-FAPi PET/CT imaging. Of the 20 patients, 12 had no evidence of recurrence or metastasis on ¹⁸F-FDG PET/CT.

Conclusion: Based on our study, ⁶⁸Ga-FAPi PET/CT alters the disease stage in the majority of gastrointestinal malignancies with negative or equivocal ¹⁸F-FDG PET/CT findings. ⁶⁸Ga-FAPi PET/CT appears to be effective in both staging and restaging of gastrointestinal malignancies, such as signet-ring cell carcinomas of the stomach that frequently show low ¹⁸F-FDG -avidity.

A 39-year-old woman presented with left neck masses for 4 months and epiphora of the left eye for 3 weeks. Ultrasonography revealed a mass in the left parotid gland and multiple cervical lymph nodes. Biopsy of the mass in the left parotid gland revealed infiltrating ductal carcinoma. ¹⁸F-fluorodeoxyglucose positron emission tomography/computed tomography scan was undertaken, which showed a mass in the left parotid gland and multiple cervical lymph nodes with high metabolism. A nodule in the left nasolacrimal duct with high metabolism was observed. The nodule was surgically removed and pathologically confirmed as metastatic parotid ductal carcinoma.

Objectives: Positron emission tomography/computed tomography (PET/CT) and magnetic resonance imaging (MRI) are widely used in the diagnosis and follow-up of liver metastases. Both modalities provide anatomical and functional information and have advantages and disadvantages. The objective of this study was to investigate the correlation between apparent diffusion coefficient (ADC) and standardized uptake value (SUV) values in metastatic liver lesions.

Methods: Abdominal magnetic resonance (MR) scans performed between April 2021 and 2024 using the 3T MR scanner were retrospectively evaluated. Thirty-three patients with liver metastases, less than one month between magnetic resonance imaging (MRI) and PET/CT, no treatment during this period, and lesions larger than 1 cm were included in the study. In each MRI scan, an index lesion was selected for ADC measurement. The radiologist and nuclear medicine specialist measured the same index lesion without the patient being informed of the results.

Results: The mean age of the 33 patients was 59±12 years, with 17 (51%) men and 16 (49%) women. The mean size of the index lesions was 27±9 mm. In MRI, mean ADC_min: (0.54±0.2) ×10^-3mm²/s; ADC_mean: (1.02±0.2) ×10^-3mm²/s; ADC_max: (1.48±0.44) ×10^-3mm²/s; and region of interest area was calculated as 6±4.6 cm². In PET/CT, mean SUV_mean: 5.8±3.3; SUV_peak: 6.8±4.3; SUV_max: 10.7±5.6; and metabolic tumor volume: 12.1 (7.4-20.7) cm³. No statistically significant correlation was found between ADC and SUV values.

Conclusion: There was no correlation between ADC and SUV values in liver metastases. Prospective studies with a large patient group are needed.

A 57-year-old man diagnosed with a metastatic bladder tumor was initiated on pembrolizumab treatment. ¹⁸F-fluorodeoxyglucose (¹⁸F-FDG) positron emission tomography/computed tomography (PET/CT) imaging performed to evaluate treatment response showed numerical-dimensional and metabolic increase in the metastatic lesions. In the ¹⁸F-FDG PET/CT imaging performed 8 weeks later due to suspicion of pseudoprogression, a significant regression of the lesions was observed, and the patient was diagnosed with pseudoprogression. Pseudoprogression should be kept in mind when ¹⁸F-FDG PET/CT is performed after the use of immunotherapy, and evaluation with follow-up PET/CT is recommended to confirm that the patient has hyperprogression or pseudoprogression.

Objectives: This study aimed to evaluate the relationship between the degree of bone marrow involvement, hematological parameters, and ¹⁸F-fluorodeoxyglucose (¹⁸F-FDG)-positron emission tomography/computed tomography (PET/CT) data in patients diagnosed with multiple myeloma.

Methods: A total of 71 patients [19 females, 52 males, mean age 67 (36-83) years] who were diagnosed with multiple myeloma between 2014 and 2021, had not received any treatment yet, and underwent ¹⁸F-FDG-PET/CT for staging were included in the study.

Results: No significant correlation was observed between bone marrow standardized uptake value (SUV)_max and plasma cell infiltration (p=0.07). However, we found that patients with visually increased bone marrow counts also had higher plasma cell infiltration rates (p=0.037). No significant correlation was found between plasma cell infiltration rates and bone marrow SUV_max and systemic inflammatory index (SII) (p=0.187 and p=0.446, respectively). However, there was a significant correlation between the SUV_max of lytic lesions showing increased ¹⁸F-FDG uptake in bone and SII (p=0.025, r=0.330).

Conclusion: We believe that ¹⁸F-FDG PET/CT may be an advantage over bone marrow biopsy in the diagnosis and evaluation of multiple myeloma recurrence and may prevent repeated bone marrow biopsies.

Objectives: Delayed [⁶⁸Ga]Ga-prostate-specific membrane antigen (PSMA) positron emission tomography/computed tomography (PET/CT) images show reduced PSMA uptake in benign lesions and increased PSMA uptake in malignant lesions. This study investigated the efficacy of PRIMARY scoring on [⁶⁸Ga]Ga-PSMA PET/CT images at standard versus delayed time points and assessed the potential added value of delayed imaging in PRIMARY scoring.

Methods: A total of 140 patients with biopsy results of International Society of Urological Pathology grade groups (ISUP) 1-2 who had standard (median 60 min) and delayed images (median 138 min) with [⁶⁸Ga]Ga-PSMA PET/CT before radical prostatectomy were included. Results were confirmed in pathological reports. For diagnostic parameters, two experienced nuclear medicine physicians, who were blinded to clinical data, independently reviewed the images, and a third physician provided consensus in cases of disagreement. PRIMARY scoring was also conducted by four nuclear medicine physicians on both images, with a 1-month interval between assessments for intraobserver agreement analyses.

Results: The percentage of lesions scored as 1-2 in PRIMARY scoring decreased from 29% to 10% in delayed images compared with standard images, whereas lesions scored as 3-5 increased from 71% to 90%. Additionally, agreement between two experienced nuclear medicine physicians regarding scoring was 66% for standard imaging and 77% for delayed imaging. The number of patients with PRIMARY score 5 increased from 31 to 46 in delayed imaging. All patients were confirmed to have clinically significant prostate cancer (csPCa). Furthermore, no csPCa of ISUP grade 3 or higher was detected in patients with a delayed PRIMARY score (dPRIMARY). The sensitivity of standard PRIMARY scoring was 71%, which increased to 92% with dPRIMARY scoring, with a consistent positive predictive value of 87% for both. Intraobserver agreement Cohen's kappa values for all observers were higher for delayed images than for standard images. Inter-observer agreement, assessed by Fleiss kappa, was 0.47 and 0.52 for standard images in rounds 1 and 2, respectively, and 0.61 and 0.72 for delayed images, respectively.

Conclusion: Decreased background activity and increased primary tumor uptake in delayed images improved differentiation between primary tumors and benign lesions, leading to better primary tumor identification. Enhanced reliability was also observed in both intraobserver and interobserver assessments of delayed images.