Aim: To investigate the prognostic value of quantitative assessment of skeletal tumor burden on bone scintigraphy (Bone Scan Index) in patients with advanced metastatic castration-resistant prostate cancer (mCRPC) receiving Radium-223-dichloride (²²³RaCl₂). We hypothesize that Bone Scan Index (BSI) can serve as a prognostic biomarker of overall survival (OS) and hematological toxicity, as well as a tool for response assessment in patients with mCRPC treated with ²²³RaCl₂. Methods: Retrospective study of the Danish cohort of mCRPC patients who received ²²³RaCl₂ therapy between March 2014 and October 2015 and for whom a baseline bone scintigraphy was available. Bone scintigraphies were reviewed and graded according to extent of disease (EOD). Furthermore, automated BSI (EXINI BoneBSI by EXINI Diagnostics, Lund, Sweden), was obtained for baseline scintigraphies and follow-up scans after three cycles as well as at end of therapy (EOT). Clinical outcomes were OS and occurrence of haematological toxicity grade 2-5. Associations between BSI and clinical outcomes were investigated in multivariate regression models including visual assessment of bone scintigraphy and other relevant covariates. Results: A total of 88 patients were included. Median number of completed ²²³RaCl₂ cycles was four and 27 patients (31%) completed six cycles. BSI was significantly associated with OS in multivariate analysis and median OS for patients with BSI > 5 was 8.2 months vs. 15.0 months for patients with BSI ≤ 5 (Hazard ratio 2.65 [95% CI: 1.5-4.71]; P = 0.001). Likewise, baseline BSI was prognostic for occurrence of hematological toxicity and patients with BSI > 5 had an odds ratio of 3.02 (95% CI: 1.2-7.8; P = 0.02) for toxicity. BSI declined during therapy in 44% of patients who completed three cycles of ²²³RaCl₂ (n = 52) and in 84% of patients after EOT (n = 32). There was no significant association between change in BSI during therapy and OS. Conclusion: BSI is a promising biomarker for late-stage mCRPC patients receiving ²²³RaCl₂ for prognostication of OS and hematological toxicity. Further prospective studies are needed to evaluate the potential for BSI in response assessment of ²²³RaCl₂ therapy.

Background: OligoG is a low molecular-weight alginate oligosaccharide that improves the viscoelastic properties of cystic fibrosis (CF) mucus and disrupts biofilms, thereby potentiating the activity of antimicrobial agents. The efficacy of inhaled OligoG was evaluated in adult patients with CF.Methods: A randomised, double-blind, placebo-controlled multicentre crossover study was used to demonstrate safety and efficacy of inhaled dry powder OligoG. Subjects were randomly allocated to receive OligoG 1050 mg per day (10 capsules three times daily) or matching placebo for 28 days, with 28-day washout periods following each treatment period. The primary end-point was absolute change in percentage predicted forced expiratory volume in 1 s (FEV₁) at the end of 28-day treatment. The intention-to-treat (ITT) population (n=65) was defined as randomised to treatment with at least one administration of study medication and post-dosing evaluation.Results: In this study, 90 adult subjects were screened and 65 were randomised. Statistically significant improvement in FEV₁was not observed in the ITT population. Adverse events included nasopharyngitis, cough and pulmonary exacerbation. The number and proportions of patients with adverse events and serious adverse events were similar between OligoG and placebo group.Conclusions: Inhalation of OligoG-dry powder over 28 days was safe in adult CF subjects. Statistically significant improvement of FEV₁was not reached. The planned analyses did not indicate a significant treatment benefit with OligoG compared to placebo.Post hocexploratory analyses showed subgroup results that indicate that further studies of OligoG in this patient population are justified.

Meta-[¹²³I]iodobenzylguanidine ([¹²³I]MIBG) scintigraphy with SPECT/CT is the standard of care for diagnosing and monitoring neuroblastoma. Replacing [¹²³I]MIBG with the new PET tracer meta-[¹⁸F]fluorobenzylguanidine ([¹⁸F]MFBG) and further improving sensitivity and reducing noise in a new long-axial-field-of-view (LAFOV) PET/CT scanner enable increased image quality and a faster acquisition time, allowing examinations to be performed without sedation or general anesthesia (GA). Focusing on feasibility, we present our first experience with [¹⁸F]MFBG LAFOV PET/CT and compare it with [¹²³I]MIBG scintigraphy plus SPECT/CT for imaging in neuroblastoma in children. Methods: A pilot of our prospective, single-center study recruited children with neuroblastoma who were referred for [¹²³I]MIBG scintigraphy with SPECT/CT. Within 1 wk of [¹²³I]MIBG scintigraphy and SPECT/low-dose CT, [¹⁸F]MFBG LAFOV PET/ultra–low-dose CT was performed 1 h after injection (1.5–3 MBq/kg) without sedation or GA, in contrast to the 24-h postinjection interval needed for scanning with [¹²³I]MIBG, the 2- to 2.5-h acquisition time, and the GA often needed in children less than 6 y old. Based on the spirocyclic iodonium-ylide precursor, [¹⁸F]MFBG was produced in a fully automated good manufacturing practice–compliant procedure. We present the feasibility of the study. Results: In the first paired scans of the first 10 children included (5 at diagnosis, 2 during treatment, 2 during surveillance, and 1 at relapse), [¹⁸F]MFBG PET/CT scan showed a higher number of radiotracer-avid lesions in 80% of the cases and an equal number of lesions in 20% of the cases. The SIOPEN score was higher in 50% of the cases, and the Curie score was higher in 70% of the cases. In particular, intraspinal, retroperitoneal lymph node, and bone marrow involvement was diagnosed with much higher precision. None of the children (median age, 1.6 y; range, 0.1–7.9 y) had sedation or GA during the PET procedure, whereas 80% had GA during [¹²³I]MIBG scintigraphy with SPECT/CT. A PET acquisition time of only 2 min without motion artifacts was the data requirement of the 10-min acquisition time for reconstruction to provide a clinically useful image. Conclusion: This pilot study demonstrates the feasibility of performing [¹⁸F]MFBG LAFOV PET/CT for imaging of neuroblastoma. Further, an increased number of radiotracer-avid lesions, an increased SIOPEN score, and an increased Curie score were seen on [¹⁸F]MFBG LAFOV PET/CT compared with [¹²³I]MIBG scintigraphy with SPECT/CT, and GA and sedation was avoided in all patients. Thus, with a 1-d protocol, a significantly shorter scan time, a higher sensitivity, and the avoidance of GA and sedation, [¹⁸F]MFBG LAFOV PET/CT shows promise for future staging and response assessment and may also have a clinical impact on therapeutic decision-making for children with neuroblastoma. Visual Abstract

Esthesioneuroblastoma (ENB) is an uncommon neuroendocrine tumor originating from the olfactory neuroepithelium and accounts for 3–6% of all intranasal tumors [¹]. ENBs can be locally aggressive and cause invasion and destruction of surrounding structures. Histological grading and clinical stage at presentation are highly predictive of survival and especially presence of lymph node and distant metastases are determining prognostic factors [²,³,⁴,⁵]. Thus, reliable imaging is essential in these patients. Conventional imaging modalities for staging ENB are magnetic resonance imaging (MRI) and computed tomography (CT). However, fluorine-18 fluoro-2-deoxy-d-glucose positron emission tomography/CT (¹⁸F-FDG PET/CT) has been reported as a valuable adjunct and was found to upstage 36% of ENB patients compared to conventional imaging [6]. We present a case demonstrating the diagnostic work-up and follow-up with ¹⁸F-FDG PET/CT in a young patient with ENB with a highly atypical clinical presentation.

The combined use of Positron Emission Tomography (PET) and Computed Tomography (CT) has become increasingly vital for diagnosing and managing oncological and infectious diseases in pediatric patients. The introduction of long axial field-of-view (LAFOV) PET/CT scanners, also known as "Total Body PET/CT," marks a significant advancement in nuclear medicine. This new technology enables faster pediatric imaging with substantially reduced radiation exposure and essentially eliminates the need for sedation, addressing previous critical concerns in pediatric imaging. This review will explore the applications and challenges of LAFOV PET/CT in pediatric imaging, highlight the benefits observed at two Danish hospitals, and evaluate its potential to transform the management of pediatric patients.