The Diagnostic Performance of 2-[18F]FDG PET/CT in Identifying Richter Transformation in Chronic Lymphocytic Leukemia: An Updated Systematic Review and Bivariate Meta-Analysis.

Richter transformation is a rare phenomenon characterized by the transformation of cell chronic lymphocytic leukemia (CLL) into a more aggressive lymphoma variant. The early identification of CLLs with a high risk of RT is fundamental. In this field, 2-deoxy-2-[18F]-fluoro-D-glucose positron emission tomography/computed tomography (2-[18F]FDG PET/CT) has been shown to be a non-invasive and promising tool, but apparently, unclear data seem to be present in the literature. This systematic review and bivariate meta-analysis aimed to investigate the diagnostic performance of 2-[18F]FDG PET/CT and its parameters in predicting RT. Between 2006 and 2024, 15 studies were published on this topic, including 1593 CLL patients. Among semiquantitative variables, SUVmax was the most investigated, and the best threshold derived for detecting RT was five. With this cut-off value, a pooled sensitivity of 86.8% (95% CI: 78.5-93.3), a pooled specificity of 48.1% (95% CI: 27-69.9), a pooled negative predictive value of 90.5% (95% CI: 88.4-92.4), a pooled negative likelihood ratio of 0.35 (95% CI: 0.17-0.70), a pooled positive likelihood ratio of 1.8 (95% CI: 1.3-2.4), and a pooled diagnostic odds ratio of 6.7 (3.5-12.5) were obtained. With a higher cut-off (SUVmax = 10), the specificity increased while the sensitivity reduced. The other metabolic features, like metabolic tumor volume, total lesion glycolysis, and radiomic features, were only marginally investigated with controversial evidence.

The Clinical Role of CXCR4-Targeted PET on Lymphoproliferative Disorders: A Systematic Review.

Background/Objectives: We conducted a comprehensive investigation to explore the pathological expression of the CXCR4 receptor in lymphoproliferative disorders (LPDs) using [68Ga]Ga-Pentixafor PET/CT or PET/MRI technology. The PICO question was as follows: What is the diagnostic role (outcome) of [68Ga]Ga-Pentixafor PET (intervention) in patients with LPDs (problem/population)? Methods: The study was written based on the reporting items for systematic reviews and meta-analyses (PRISMA) 2020 guidelines, and it was registered on the prospective register of systematic reviews (PROSPERO) website (CRD42024506866). A comprehensive computer literature search of Scopus, MEDLINE, Scholar, and Embase databases was conducted, including articles indexed up to February 2024. To the methodological evaluation of the studies used the quality assessment of diagnosis accuracy studies-2 (QUADAS-2) tool. Results: Of the 8380 records discovered, 23 were suitable for systematic review. Fifteen studies (on 571 LPD patients) focused on diagnosis and staging, and eight trials (194 LPD patients) assessed treatment response. Conclusions: The main conclusions that can be inferred from the published studies are as follows: (a) [68Ga]Ga-Pentixafor PET may have excellent diagnostic performance in the study of several LPDs; (b) [68Ga]Ga-Pentixafor PET may be superior to [18F]FDG or complementary in some LPDs variants and settings; (c) multiple myeloma seems to have a high uptake of [68Ga]Ga-Pentixafor. Overall, this technique is probably suitable for imaging, staging, and follow-up on patients with LPD. Due to limited data, further studies are warranted to confirm the promising role of [68Ga]Ga-Pantixafor in this context.

[The telephone follow-up by a nurse case manager in major surgery. A prospective observational study]. / Il follow-up infermieristico telefonico nell'ambito del case management in chirurgia maggiore. Uno studio osservazionale prospettico.

. The telephone follow-up by a nurse case manager in major surgery. A prospective observational study. INTRODUCTION: One of the methods used in case management is a structured telephone follow-up, helpful in improving patient satisfaction, supporting autonomy, and addressing information needs post-discharge. OBJECTIVE: To describe the experience of nursing case management and post-hospital telephone follow-up in patients undergoing major abdominal surgery. METHOD: Single-centre prospective observational study. All consecutive patients undergoing major abdominal surgery from April 2021 to May 2022 were included. Symptoms and nursing care needs during the post-discharge period, along with case management interventions, were described. RESULTS: Of the 205 patients included in the study, 89.8% underwent elective surgery and 135 (65.9%) did not develop postoperative complications, with a median hospital stay of 8 days. 182 (88.8%) patients reported at least one postoperative symptom, with fatigue, altered bowel movements, pain, and lack of appetite being the most common. Interventions provided by the case manager decreased progressively over time, from 149 at the first telephone contact (72%) to 44 at the third (25%). A total of 22 patients (10.7%) were readmitted to the hospital, 12 of whom on the recommendation of the case manager. CONCLUSIONS: After discharge, patients experience numerous issues: although the symptoms encountered are common during the post-operative period, they often require support beyond the patient's capacity. The intervention of the case manager with information and support for self-management of symptoms enabled the early identification of risk situations.

Diagnostic yield of FAP-guided positron emission tomography in thyroid cancer: a systematic review.

Background: Several recent studies have proposed the possible application of positron emission tomography/computed tomography (PET/CT) administering radiolabelled fibroblast-activation protein (FAP) inhibitors for various forms of thyroid cancer (TC), including differentiated TC (DTC), and medullary TC (MTC). Methods: The authors conducted an extensive literature search of original studies examining the effectiveness of FAP-guided PET/CT in patients with TC. The papers included were original publications exploring the use of FAP-targeted molecular imaging in restaging metastatic DTC and MTC patients. Results: A total of 6 studies concerning the diagnostic yield of FAP-targeted PET/CT in TC (274 patients, of which 247 DTC and 27 MTC) were included in this systematic review. The included articles reported high values of FAP-targeted PET/CT detection rates in TC, ranging from 81 to 100% in different anatomical sites and overall superior to the comparative imaging method. Conclusion: Although there are promising results, the existing literature on the diagnostic accuracy of FAP-guided PET in this context is still quite limited. To thoroughly evaluate its potential significance in TC patients, it is needed to conduct prospective randomized multicentric trials.

Implementation of an enhanced recovery after surgery protocol for colorectal cancer in a regional hospital network supported by audit and feedback: a stepped wedge, cluster randomised trial.

BACKGROUND: Enhanced recovery after surgery (ERAS) protocols are known to potentially improve the management and outcomes of patients undergoing colorectal surgery, with limited evidence of their implementation in hospital networks and in a large population. We aimed to assess the impact of the implementation of an ERAS protocol in colorectal cancer surgery in the entire region of Piemonte, Italy, supported by an audit and feedback (A&F) intervention. METHODS: A large, stepped wedge, cluster randomised trial enrolled patients scheduled for elective surgery at 29 general surgery units (clusters). At baseline (first 3 months), standard care was continued in all units. Thereafter, four groups of clusters began to adopt the ERAS protocol successively. By the end of the study, each cluster had a period in which standard care was maintained (control) and a period in which the protocol was applied (experimental). ERAS implementation was supported by initial training and A&F initiatives. The primary endpoint was length of stay (LOS) without outliers (>94th percentile), and the secondary endpoints were outliers for LOS, postoperative medical and surgical complications, quality of recovery and compliance with ERAS items. RESULTS: Of 2626 randomised patients, 2397 were included in the LOS analysis (1060 in the control period and 1337 in the experimental period). The mean LOS without outliers was 8.5 days during the control period (SD 3.9) and 7.5 (SD 3.5) during the experimental one. The adjusted difference between the two periods was a reduction of -0.58 days (95% CI -1.07, -0.09; p=0.021). The compliance with ERAS items increased from 52.4% to 67.3% (estimated absolute difference +13%; 95% CI 11.4%, 14.7%). No difference in the occurrence of complications was evidenced (OR 1.22; 95% CI 0.89, 1.68). CONCLUSION: Implementation of the ERAS protocol for colorectal cancer, supported by A&F approach, led to a substantial improvement in compliance and a reduction in LOS, without meaningful effects on complications. Trial registration number NCT04037787.

Implementing Enhanced Recovery After Surgery for hysterectomy in a hospital network with audit and feedback: A stepped-wedge cluster randomised trial.

OBJECTIVE: To evaluate the effectiveness of implementing the Enhanced Recovery After Surgery (ERAS) protocol in patients undergoing elective hysterectomy in a network of regional hospitals, supported by an intensive audit-and-feedback (A&F) approach. DESIGN: A multi-centre, stepped-wedge cluster randomised trial (ClinicalTrials.gov NCT04063072). SETTING: Gynaecological units in the Piemonte region, Italy. POPULATION: Patients undergoing elective hysterectomy, either for cancer or for benign conditions. METHODS: Twenty-three units (clusters), stratified by surgical volume, were randomised into four sequences. At baseline (first 3 months), standard care was continued in all units. Subsequently, the four sequences implemented the ERAS protocol successively every 3 months, after specific training. By the end of the study, each unit had a period in which standard care was maintained (control) and a period in which the protocol, supported by feedback, was applied (experimental). MAIN OUTCOME MEASURES: Length of hospital stay (LOS), without outliers (>98th percentile). RESULTS: Between September 2019 and May 2021, 2086 patients were included in the main analysis with an intention-to-treat approach: 1104 (53%) in the control period and 982 (47%) in the ERAS period. Compliance with the ERAS protocol increased from 60% in the control period to 76% in the experimental period, with an adjusted absolute difference of +13.3% (95% CI 11.6% to 15.0%). LOS, moving from 3.5 to 3.2 days, did not show a significant reduction (-0.12 days; 95% CI -0.30 to 0.07 days). No difference was observed in the occurrence of complications. CONCLUSIONS: Implementation of the ERAS protocol for hysterectomy at the regional level, supported by an A&F approach, resulted in a substantial improvement in compliance, but without meaningful effects on LOS and complications. This study confirms the effectiveness of A&F in promoting important innovations in an entire hospital network and suggests the need of a higher compliance with the ERAS protocol to obtain valuable improvements in clinical outcomes.

The prognostic role of next-generation imaging-driven upstaging in newly diagnosed prostate cancer patients.

PURPOSE: Phase III evidence showed that next-generation imaging (NGI), such as prostate-specific membrane antigen positron emission tomography/computed tomography (PSMA PET/CT), provides higher diagnostic accuracy than bone scan and contrast-enhanced computed tomography (conventional imaging, CI) in the primary staging of intermediate-to-high-risk prostate cancer (PCa) patients. However, due to the lack of outcome data, the introduction of NGI in routine clinical practice is still debated. Analysing the oncological outcome of patients upstaged by NGI (though managed according to CI) might shed light on this issue, supporting the design of randomised trials comparing the effects of treatments delivered based on NGI vs. CI. METHODS: We prospectively enrolled a cohort of 100 biopsy-proven intermediate-to-high-risk PCa patients staged with CI and PSMA PET/CT (though managed according to the CI stage), to assess the frequency of the stage migration phenomenon. Stage migration was then assessed as biochemical recurrence-free survival (bRFS) predictor. RESULTS: Three patients were lost at follow-up after imaging. PSMA PET/CT upstaged 26.8% of patients compared to CI, while it downstaged 6.1% of patients. Notably, 50% of patients excluded from surgery due to the presence of bone metastases at CI would have been treated with radical-intent approaches if PSMA PET/CT had guided the treatment choice. After a median follow-up of 6 months of surgically treated patients, 22/83 (26.5%) had biochemical recurrence (BCR). PSMA PET/CT-driven upstaging determined a significant risk increase for BCR (HR:3.41, 95%CI:1.21-9.56, p = 0.019). Including stage migration in a univariable and multivariable model identified PSMA PET/CT-upstaging as an independent predictor of bRFS. CONCLUSIONS: In conclusion, implementing NGI for staging purposes improves the prediction of bRFS. Although phase III evidence is still needed, this advancement suggests that NGI may better identify patients who would benefit from local treatments than those who may achieve better oncological outcomes through systemic treatment.

Diagnostic Accuracy of PET with 18F-Fluciclovine ([18F]FACBC) in Detecting High-Grade Gliomas: A Systematic Review and Meta-Analysis.

BACKGROUND: 18F-Fluciclovine ([18F]FACBC) has been recently proposed as a synthetic radiolabeled amino acid for positron emission tomography (PET) imaging in patients with brain neoplasms. Our aim is to evaluate the diagnostic performance of [18F]FACBC PET in high-grade glioma (HGG) patients, taking into account the literature data. METHODS: A comprehensive literature search was performed. We included original articles evaluating [18F]FACBC PET in the detection of HGG before therapy and for the suspicion of tumor recurrence. Pooled sensitivity, specificity, positive and negative likelihood ratios (LR+ and LR-), and diagnostic odds ratios (DOR), including 95% confidence intervals (95% CI), were measured. Statistical heterogeneity and publication bias were also assessed. RESULTS: ten studies were included in the review and eight in the meta-analysis (113 patients). Regarding the identification of HGG, the sensitivity of [18F]FACBC PET ranged between 85.7% and 100%, with a pooled estimate of 92.9% (95% CI: 84.4-96.9%), while the specificity ranged from 50% to 100%, with a pooled estimate of 70.7% (95% CI: 47.5-86.5%). The pooled LR+, LR-, and DOR of [18F]FACBC PET were 2.5, 0.14, and 37, respectively. No significant statistical heterogeneity or publication bias were found. CONCLUSIONS: evidence-based data demonstrate the good diagnostic accuracy of [18F]FACBC PET for HGG detection. Due to the still limited data, further studies are warranted to confirm the promising role of [18F]FACBC PET in this context.

Diagnostic Accuracy of [68Ga]Ga Labeled Fibroblast-Activation Protein Inhibitors in Detecting Head and Neck Cancer Lesions Using Positron Emission Tomography: A Systematic Review and a Meta-Analysis.

Several studies have examined the use of positron emission tomography (PET) using [68Ga]Ga-radiolabeled fibroblast-activation protein inhibitors (FAPi) across multiple subtypes of head and neck cancer (HNC). The purpose of the present study was to evaluate the diagnostic accuracy of a newly developed molecular imaging approach in the context of HNC through a comprehensive review and meta-analysis. A thorough literature review was conducted to identify scholarly articles about the diagnostic effectiveness of FAP-targeted PET imaging. The present study incorporates original publications assessing the efficacy of this innovative molecular imaging test in both newly diagnosed and previously treated HNC patients. This systematic review examined eleven investigations, of which nine were deemed suitable for inclusion in the subsequent meta-analysis. The quantitative synthesis yielded a pooled detection rate of 99% for primary HNC lesions. Additionally, on a per patient-based analysis, the pooled sensitivity and specificity for regional lymph node metastases were found to be 90% and 84%, respectively. The analysis revealed a statistical heterogeneity among the studies for the detection rate of primary HNC lesions. The quantitative findings presented in this study indicate a favorable diagnostic performance of FAP-targeted PET imaging in detecting primary HNC tumors. In contrast, discordant results concerning the diagnostic accuracy of lymph node metastases were found. However, further multicentric trials are required to validate the efficacy of FAP-targeted PET in this specific group of patients.

18F-Fluorocholine PET/CT in the Detection of Hyperfunctioning Transplanted Parathyroid Tissue.

ABSTRACT: A 54-year-old woman diagnosed with multiple endocrine neoplasia syndrome type 1 and primary hyperparathyroidism underwent total parathyroidectomy with autotransplantation of parathyroid tissue fragments in the right forearm in 1999. Since several years later, follow-up laboratory examinations showed the relapse of hypercalcemia; the patient started cinacalcet therapy. To exclude the presence of hyperfunctioning parathyroid glands in ortotopic or ectopic sites, a PET/CT scan with 18F-fluorocholine was performed. The PET/CT scan excluded the presence of ortotopic and ectopic parathyroid glands but showed a hyperplastic parathyroid fragment in the right forearm, responsible for the patient's persistent hypercalcemia.

Prevalence of Incidental Findings Suspicious for Transthyretin Cardiac Amyloidosis among Patients Undergoing Bone Scintigraphy: A Systematic Review and a Meta-Analysis.

BACKGROUND: The myocardial uptake of bone-seeking tracers suspicious for transthyretin cardiac amyloidosis (ATTR-CA) can be incidentally detected in patients undergoing bone scintigraphy for noncardiac reasons. We conducted a systematic review and meta-analysis to assess the prevalence of these scintigraphic findings. METHODS: A comprehensive literature search was performed using two bibliographic databases (PubMed/MEDLINE and Cochrane Library), searching for articles related to the review question. Eligible articles were selected, and relevant data were extracted by two authors. The pooled prevalence of incidental findings suspicious for ATTR-CA among patients undergoing bone scintigraphy was calculated on a per-patient-based analysis using a random-effects model. The pooled measure was provided with 95% confidence interval (95% CI) values. RESULTS: Among 219 records, 11 articles were selected for the systematic review and 10 for the meta-analysis. The pooled prevalence of incidental findings suspicious for ATTR-CA was 1.1% (95% CI: 0.7-1.4%) with heterogeneity due to the characteristics of the included studies, patients, and index tests. These findings are more prevalent in older men. CONCLUSIONS: The prevalence of incidental findings of ATTR-CA among patients undergoing bone scintigraphy is low but not negligible. Nuclear medicine physicians should suggest, in the scintigraphic report, further clinical investigations when these findings are detected. Prospective studies are warranted.

Assessing the role of colonic and other anatomical sites uptake by [18 F]FDG-PET/CT and immune-inflammatory peripheral blood indexes in patients with advanced non-small cell lung cancer treated with first-line immune checkpoint inhibitors.

BACKGROUND: Inflammation in non-small cell lung cancer (NSCLC) may impair the response to immune checkpoint inhibitors (ICIs) and can be indicated by peripheral blood inflammatory indexes. 2-deoxy-2-[18 F]fluoro-D-glucose positron emission tomography/computed tomography ([18 F] FDG-PET/CT) may be used as a marker of inflammation by measuring glucose metabolism in different colonic sites. METHODS: This retrospective analysis aimed to investigate the correlation between [18 F] FDGPET/CT SUVratio in six gastrointestinal districts, the spleen, the pharynx and the larynx alongside the most avid tumor lesion with peripheral blood inflammatory indexes, including the neutrophil-to-lymphocyte ratio (NLR), systemic immune-inflammatory index (SII, i.e., NLR times platelets) and lactate dehydrogenase (LDH), in patients with [18 F] FDG-PET/CT staged IV NSCLC who received first-line immune checkpoint inhibitors (ICIs). The role of SUVratios and peripheral blood inflammatory indexes in predicting overall survival (OS) and progression-free survival (PFS) was then explored. RESULTS: A total of 43 patients were treated with first-line ICI alone (58%) or in combination with chemotherapy (42%). A significant correlation was only found between the rectosigmoid SUVratio and NLR (p = 0.0465). NLR >5.5 and LDH > 333.5 were associated with a worse OS (p = 0.033 and p = 0.009, respectively). The SII was associated with a worse PFS in patients treated with ICI alone (p = 0.033). None of the SUVratios were significantly associated with OS or PFS, although a high left colon SUVratio showed a trend toward a worse PFS. CONCLUSION: There was no significant correlation between [18 F]FDG PET/CT uptake in different anatomical sites, and in the tumor, and systemic immune-inflammatory indexes. The prognostic role of high left colon SUVratio deserves further investigation.

Diagnostic Performance of Positron Emission Tomography with Fibroblast-Activating Protein Inhibitors in Gastric Cancer: A Systematic Review and Meta-Analysis.

Various papers have introduced the use of positron emission tomography (PET) with [68Ga]Ga-radiolabeled fibroblast-activation protein inhibitor (FAPi) radiopharmaceuticals in different subtypes of gastric cancer (GC). Our aim was to assess the diagnostic performance of this novel molecular imaging technique in GC with a systematic review and meta-analysis. A straightforward literature search of papers concerning the diagnostic performance of FAP-targeted PET imaging was performed. Original articles evaluating this novel molecular imaging examination in both newly diagnosed GC patients and GC patients with disease relapse were included. The systematic review included nine original studies, and eight of them were also eligible for meta-analysis. The quantitative synthesis provided pooled detection rates of 95% and 97% for the assessment of primary tumor and distant metastases, respectively, and a pooled sensitivity and specificity of 74% and 89%, respectively, for regional lymph node metastases. Significant statistical heterogeneity among the included studies was found only in the analysis of the primary tumor detection rate (I2 = 64%). Conclusions: Beyond the limitations of this systematic review and meta-analysis (i.e., all the included studies were conducted in Asia, and using [18F]FDG PET/CT as a comparator of the index test), the quantitative data provided demonstrate the promising diagnostic performance of FAP-targeted PET imaging in GC. Nevertheless, more prospective multicentric studies are needed to confirm the excellent performances of FAP-targeted PET in this cluster of patients.

Dose-response Analysis in Hepatic Tumors Treated with 90Y-TARE According to a Personalized Dosimetric Workflow: Preliminary Results.

BACKGROUND: Transarterial Radioembolization (TARE) is a widespread radiation therapy for unresectable hepatic lesions, but a clear understanding of the dose-response link is still missing. The aim of this preliminary study is to investigate the role of both dosimetric and clinical parameters as classifiers or predictors of response and survival for TARE in hepatic tumors and to present possible response cut-off. METHODS: 20 patients treated with glass or resin microspheres according to a personalized workflow were included. Dosimetric parameters were extracted from personalized absorbed dose maps obtained from the convolution of 90Y PET images with 90Y voxel S-values. RESULTS: D95 ≥ 104 Gy and tumor mean absorbed dose MADt ≥ 229 Gy were found to be optimal cut-off values for complete response, while D30 ≥ 180 Gy and MADt ≥ 117 Gy were selected as cut-off values for at least partial response and predicted better survival. Clinical parameters Alanine Transaminase (ALT) and Model for End-Stage Liver Disease (MELD) didn't show sufficient classification capability for response or survival. CONCUSION: These preliminary results highlight the importance of an accurate dosimetric evaluation and suggest a cautious approach when considering clinical indicators. Dosimetric cut-off values could be a support tool in both planning and post-treatment phases. Larger multi-centric randomized trials, with standardized methods regarding patient selection, response criteria, Regions of Interest definition, dosimetric approach and activity planning are needed to confirm these promising results.

18F-FDG PET/CT Maximum Tumor Dissemination (Dmax) in Lymphoma: A New Prognostic Factor?

Recently, several studies introduced the potential prognostic usefulness of maximum tumor dissemination (Dmax) measured by 2-deoxy-2-fluorine-18-fluoro-D-glucose positron-emission tomography/computed tomography (18F-FDG PET/CT). Dmax is a simple three-dimensional feature that represents the maximal distance between the two farthest hypermetabolic PET lesions. A comprehensive computer literature search of PubMed/MEDLINE, Embase, and Cochrane libraries was conducted, including articles indexed up to 28 February 2023. Ultimately, 19 studies analyzing the value of 18F-FDG PET/CT Dmax in patients with lymphomas were included. Despite their heterogeneity, most studies showed a significant prognostic role of Dmax in predicting progression-free survival (PFS) and overall survival (OS). Some articles showed that the combination of Dmax with other metabolic features, such as MTV and interim PET response, proved to better stratify the risk of relapse or death. However, some methodological open questions need to be clarified before introducing Dmax into clinical practice.

The Role of Theragnostics in Breast Cancer: A Systematic Review of the Last 12 Years.

BACKGROUND: Breast cancer is the most common malignancy in women, with high morbidity and mortality. Molecular alterations in breast cancer involve the expression or upregulation of various molecular targets that can be used for diagnostic nuclear medicine imaging and radiopharmaceutical treatment. Theragnostics is based on the binding of radionuclides to molecular targets. These radionuclides can induce a cytotoxic effect on the specific tumor cell (target) or its vicinity, thus allowing a personalized approach to patients with effective treatment and comparably small side effects. AIM: This review aims to describe the most promising molecular targets currently under investigation for theragnostics and precision oncology in breast cancer. METHODS: A comprehensive literature search of studies on theragnostics in breast cancer was performed in the PubMed, PMC, Scopus, Google Scholar, Embase, Web of Science, and Cochrane library databases, between 2010 and 2022, using the following terms: breast neoplasm*, breast, breast cancer*, theragnostic*, theranostic*, radioligand therap*, RLT, MET, FLT, FMISO, FES, estradiol, trastuzumab, PD-L1, PSMA, FAPI, FACBC, fluciclovine, FAZA, GRPR, DOTATOC, DOTATATE, CXC4, endoglin, gastrin, mucin1, and syndecan1. RESULTS: Fifty-three studies were included in the systematic review and summarized in six clinical sections: 1) human epidermal growth factor receptor 2 (HER2); 2) somatostatin receptors (SSTRS); 3) prostate-specific membrane antigen radiotracers (PSMA); 4) fibroblast activation protein-α targeted radiotracers; 5) gastrin-releasing peptide receptor-targeted radiotracers; 6) other radiotracers for theragnostics. CONCLUSION: The theragnostic approach will progressively allow better patient selection, and improve the prediction of response and toxicity, avoiding unnecessary and costly treatment.

Potential Role of PSMA-Targeted PET in Thyroid Malignant Disease: A Systematic Review.

BACKGROUND: Recently, several studies introduced the potential use of positron emission tomography/computed tomography (PET/CT) with prostate-specific membrane antigen (PSMA)-targeting radiopharmaceuticals in radioiodine-refractory thyroid cancer (TC). METHODS: The authors accomplished a comprehensive literature search of original articles concerning the performance of PSMA-targeted PET/CT in TC patients. Original papers exploring this molecular imaging examination in radioiodine-refractory TC patients undergoing restaging of their disease were included. RESULTS: A total of 6 documents concerning the diagnostic performance of PSMA-targeted PET/CT in TC (49 patients) were included in this systematic review. The included articles reported heterogeneous values of PSMA-targeted PET/CT detection rates in TC, ranging from 25% to 100% and overall inferior to [18F]-fluorodeoxyglucose PET/CT when the two molecular imaging examinations were compared. Two studies reported the administration of [177Lu]PSMA-radioligands with theragnostic purpose in three patients. CONCLUSIONS: The available literature data in this setting are limited and heterogeneous. The employment of PET with PSMA-targeting radiopharmaceuticals in this setting did not affect patient management. Nevertheless, prospective multicentric studies are needed to properly assess its potential role in TC patients.

The Emerging Role of PET/CT with PSMA-Targeting Radiopharmaceuticals in Clear Cell Renal Cancer: An Updated Systematic Review.

BACKGROUND: Recent articles proposed the employment of positron emission tomography/computed tomography (PET/CT) with prostate-specific membrane antigen (PSMA)-targeting radiopharmaceuticals in clear cell renal cell carcinoma (ccRCC). METHODS: The authors performed a comprehensive literature search of studies on the performance of PET/CT with PSMA-targeting radiopharmaceuticals in ccRCC. Original articles concerning this imaging examination were included in newly diagnosed ccRCC patients and ccRCC patients with disease recurrence. RESULTS: A total of sixteen papers concerning the diagnostic performance of PSMA-targeted PET/CT in ccRCC (331 patients) were included in this systematic review. The included articles demonstrated an excellent detection rate of PSMA-targeting PET/CT in ccRCC. CONCLUSIONS: PSMA-targeted PET/CT seems promising in detecting ccRCC lesions as well as in discriminating the presence of aggressive phenotypes. Prospective multicentric studies are warranted to strengthen the role of PSMA-targeting PET/CT in ccRCC.

18F-FDG PET/CT concurrent with first radioiodine post-therapeutic scan in high risk differentiated thyroid cancer: a useful tool or just an expensive diversion?

BACKGROUND: Aim of the present study was to evaluate the clinical impact of fluorine-18F-fluorodeoxyglucose PET/CT (18F-FDG-PET/CT) concurrent with post-therapeutic whole-body radioiodine scan (TxWBS) after first radioiodine (RAI) treatment in patients with high-risk differentiated thyroid carcinoma (DTC). METHODS: This was a retrospective, single-center study including 39 patients with DTC (22 females, 17 males, median age 54; IQR: 35-60 years, 87% papillary thyroid cancer, 13% follicular thyroid cancer). All patients underwent 18F-FDG-PET/CT and RAI treatment, both performed off L-T4 about 3 months after total thyroidectomy. TxWBS was obtained 3 days afterwards using planar technique and SPECT/CT of neck and thorax regions. Semiquantitative analysis was performed on positive 18F-FDG-PET/CT scans to assess SUVmax, SUVratio, MTV and TLG values in target lesions (hottest 18F-FDG-positive lesion present in each patient). Receiver operating characteristics (ROC) curve analysis was obtained to establish a cut-off point for SUVmax able to predict the presence of RAI nonavid lesions. Univariate and multivariate analyses were executed to find out predictive factors for abnormal 18F-FDG-PET/CT imaging. RESULTS: In 11 (28%) patients 18F-FDG-PET/CT and TxWBS were both negative and in 9 (23%) both positive, showing loco-regional or distant metastases. In 14 patients (36%) 18F-FDG-PET/CT showed more lesions than TxWBS, while in 5 (13%) patients more lesions were present at TxWBS than 18F-FDG-PET/CT. Overall, 23 patients (59%) showed 18F-FDG avid lesions and 18F-FDG-PET/TC changed the management in 14 (36%), including the choice to perform RAI therapy with higher activities than expected, lymph-node dissection for loco-regional metastases, direct therapy for solitary bone metastases. Through ROC curve analysis, a value superior to 7.25 of SUVmax was able to predict the presence of RAI non-avid lesion at TxWBS. Serum stimulated thyroglobulin and extranodal invasion resulted to be risk factors for abnormal 18F-FDG-PET/CT imaging. However, only extranodal invasion turned out to be an independent risk factor for abnormal 18F-FDG-PET/CT. CONCLUSIONS: The present study demonstrated the clinical value of RAI-concurrent 18F-FDG-PET/CT in patients with high-risk DTC. However, some questions remain open, including the pretherapeutic thyroglobulin level to use as indication to 18F-FDG-PET/CT and the predictive value of 18F-FDG-PET/CT semiquantitative parameters.