Journal of nuclear medicine : official publication, Society of Nuclear Medicine最新文献

Chemotherapy-induced cognitive impairment is increasingly recognized in leukemia survivors. Its underlying neurobiologic correlations remain unclear. This study investigated voxel-based alterations in brain glucose metabolism after chemotherapy using high-resolution [¹⁸F]FDG PET/CT. Methods: This retrospective study included 100 adults with leukemia, both newly diagnosed and relapsed, who underwent [¹⁸F]FDG PET/CT brain imaging. Patients were grouped by chemotherapy exposure: recent (≤1 y), prior (>1 y), and none (chemotherapy-naïve controls). Brain metabolism was quantified using MIM software and normalized to reference regions. Statistical analysis included t tests and ANOVA, adjusted for age and sex. Results: Among 100 patients (49 recent, 22 prior, and 29 control), chemotherapy-exposed individuals showed significant metabolic alterations compared with controls. Decreased uptake was found in the posterior cingulate gyrus (1.33 vs. 1.36; P = 0.04), anterior orbital gyrus (1.05 vs. 1.11; P = 0.05), and thalami (1.19 vs. 1.24; P = 0.05). In patients aged 55 y or older, reduced metabolism was observed in the Rolandic operculum (1.12 vs. 1.19; P < 0.001) and inferior frontal gyrus (1.16 vs. 1.19; P = 0.05). Recent chemotherapy recipients showed increased metabolism in the fusiform gyrus (1.34 vs. 1.27; P = 0.04) and insula, whereas long-term survivors did not. Intrathecal chemotherapy was linked to reduced thalamic metabolism (1.11 vs. 1.15; P = 0.02). Conclusion: Chemotherapy is associated with voxel-based brain metabolic alterations, particularly in areas governing cognition and emotion. Effects are more pronounced in older adults and those receiving intrathecal treatment. These findings support research into metabolic imaging biomarkers for early detection and intervention in chemotherapy-induced cognitive impairment.

The field of theranostics dates back over 80 y, when Hertz and Roberts first used radioactive iodine to treat thyroid disease. Recent theranostic approvals for neuroendocrine tumors and prostate cancer have expanded the use of radiopharmaceutical therapy (RPT), and there is significant near-term potential for further expansion across multiple tumor types. This Society of Nuclear Medicine and Molecular Imaging (SNMMI) position paper emphasizes the leadership role of nuclear medicine and nuclear medicine professionals in the high-quality and safe delivery of RPT through specific training, education, regulatory guidance, and collaborations. The rapidly increasing demand for access to and delivery of radiopharmaceuticals has the potential to spur hundreds of thousands of cycles of RPT, with the resultant need for hundreds of new centers and more experts to deliver these therapies. Such an expansion would involve the entire SNMMI membership, including physicians, technologists, radiochemists, physicists, radiopharmacists, scientists, and allied health professionals. All nuclear medicine team members are accredited by specific training programs covering the selection and use of radiopharmaceuticals for theranostics to minimize risks and tailor procedures to the needs of individual patients. The administration of RPT without appropriate training and experience poses significant risks in terms of patient outcomes, impacting safety, efficacy, and overall quality of care. For over 70 y, SNMMI has set comprehensive standards and clinical guidelines for the entire field of nuclear medicine, including RPT, which undergo continual review and updating. Recently, SNMMI established RPT Centers of Excellence and, in collaboration with the International Accreditation Commission (IAC), an accreditation program for facilities administering RPT. Through the Clinical Trials Network (CTN) and Therapy Clinical Trials Network (TCTN), the SNMMI also supports research and quality assurance for imaging cameras used to evaluate patients receiving RPT in clinical trials. Furthermore, collaborations with other international nuclear medicine societies ensure the continual promotion of best practices and knowledge sharing to advance the field of nuclear medicine globally.

Prostate-specific membrane antigen (PSMA) PET/CT has become a common staging modality for newly diagnosed high-risk and unfavorable intermediate-risk prostate cancer after showing improved sensitivity and specificity compared with conventional imaging in clinical trials. We aimed to assess the causal impact of PSMA PET staging on initial treatment selection in real-world practice. Methods: We used observational data from the U.S. Veterans Health Administration to emulate a randomized controlled trial in which patients with newly diagnosed, unfavorable intermediate-, high-, and very-high-risk prostate cancer from January 2022 to December 2023 would have been randomized to undergo either upfront ¹⁸F- or ⁶⁸Ga-PSMA PET staging or conventional imaging (^99mTc bone scan and pelvic CT or MRI). Outcomes of interest included use of frontline androgen deprivation therapy (ADT), second-generation androgen receptor pathway inhibitors (ARPIs), radiotherapy, and radical prostatectomy. Weighted univariable Cox regression was performed to assess the effect of treatment group on each outcome, and 95% CIs were generated from 1,000 bootstrap replicates. Results: In total, 9,049 patients met the criteria for inclusion. PSMA PET staging was associated with higher rates of any ADT use relative to conventional staging (adjusted hazard ratio [aHR], 1.26; 95% CI, 1.19-1.44), higher rates of ARPI use (aHR, 1.52; 95% CI, 1.33-1.78), lower rates of prostatectomy (aHR, 0.69; 95% CI, 0.56-0.83), and no significant effect on the use of radiotherapy (aHR, 1.10; 95% CI, 0.99-1.25). Compared with patients with PSMA stage N0M0, ARPI use was more common in patients with PSMA stage N1M0 (aHR, 6.87; 95% CI, 5.41-8.73) and PSMA stage M1 (aHR, 10.13; 95% CI, 8.16-1.2.58). Patients with PSMA N1M0 disease were much less likely to undergo prostatectomy compared with PSMA N0M0. Conclusion: PSMA PET staging may be leading to fewer prostatectomies and higher use rates of ADT and ARPIs in the Veterans Health Administration.

Cytokines are small proteins that directly regulate immune cell proliferation and signaling. An improved understanding of cytokine expression in specific microenvironments provides critical insights into essential physiologic and pathophysiologic responses to disease and infection. Standard methods used to detect and quantify cytokines are not fully suitable for this purpose, given their limited sensitivity and capacity to address cytokine heterogeneity and short biologic half-lives. In contrast, nuclear imaging modalities (e.g., PET, SPECT) can be used to detect cytokine binding in situ in real time. In this review, we discuss some of the most promising preclinical nuclear imaging agents that have been developed to target specific cytokines. These agents may ultimately be used in the clinical setting to monitor disease progression and responses to treatments for cancer and autoimmune and inflammatory diseases.

Standardized prostate-specific membrane antigen (PSMA) PET/CT evaluation and reporting was introduced to aid interpretation, reproducibility, and communication. Artificial intelligence may enhance these efforts. This study aimed to evaluate the performance of aPROMISE, a deep learning segmentation and reporting software for PSMA PET/CT, compared with a standard image viewer (IntelliSpace Portal [ISP]) in patients undergoing PSMA-radioguided surgery. This allowed the correlation of target lesions with histopathology as a standard of truth. Methods: [⁶⁸Ga]Ga-PSMA-I&T PET/CT of 96 patients with biochemical persistence or recurrence after prostatectomy (median prostate-specific antigen, 0.56 ng/mL; interquartile range, 0.31-1.24 ng/mL), who underwent PSMA-radioguided surgery, were retrospectively analyzed (twice with ISP and twice with aPROMISE) by 2 readers. Cohen κ with 95% CI was calculated to assess intra- and interrater agreement for miTNM stages. Differences between miTNM codelines were classified as no difference, minor difference (change of lymph node region without N/M change), and major difference (miTNM change). Results: Intrarater agreement rates were high for all categories, both readers, and systems (≥91.7%) with moderate to almost perfect κ values (reader 1, ISP, ≥0.51; range, 0.21-0.9; aPROMISE, ≥0.64; range, 0.41-0.99; reader 2, ISP, ≥0.83; range, 0.69-1; aPROMISE, ≥0.78; range, 0.63-1). Major differences occurred more frequently for reader 1 than for reader 2 (ISP, 26% vs. 13.5%; aPROMISE, 22.9% vs. 12.5%). Interrater agreement rates were high with both systems (≥92.2%), demonstrating substantial κ values (ISP, ≥0.73; range, 0.47-0.99; aPROMISE, ≥0.74; range, 0.54-1) with major miTNM staging differences in 21 (21.9%) cases. Readers identified 140 lesions by consensus, of which aPROMISE automatically segmented 129 (92.1%) lesions. Unsegmented lesions either were adjacent to high urine activity or demonstrated low PSMA expression. Agreement rates between imaging and histopathology were substantial (≥86.5%), corresponding to moderate to substantial κ values (≥0.6; range, 0.45-1) with major staging differences in 33 (34.4%) patients. This included 13 (13.5%) cases with metastases distant from targets identified on imaging. One of these lesions was automatically segmented by aPROMISE. Conclusion: Intra- and interreader agreement for PSMA PET/CT evaluation were similarly high with ISP and aPROMISE. The algorithm segmented 92.1% of all identified lesions. Software applications with artificial intelligence could be applied as support tools in PSMA PET/CT evaluation of early prostate cancer.