Performing [18F]MFBG Long-Axial-Field-of-View PET/CT Without Sedation or General Anesthesia for Imaging of Children with Neuroblastoma.

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.

Effects of Peptide Receptor Radiotherapy in Patients with Advanced Paraganglioma and Pheochromocytoma: A Nation-Wide Cohort Study.

INTRODUCTION: Pheochromocytomas and paragangliomas are rare neuroendocrine tumours that originate from chromaffin cells within the adrenal medulla or extra-adrenal sympathetic ganglia. Management of disseminated or metastatic pheochromocytomas and paragangliomas continues to pose challenges and relies on limited evidence. METHOD: In this study, we report retrospective data on median overall survival (OS) and median progression-free survival (PFS) for all Danish patients treated with peptide receptor radionuclide therapy (PRRT) with 177Lu-Dotatate or 90Y-Dotatate over the past 15 years. One standard treatment of PRRT consisted of 4 consecutive cycles with 8-14-week intervals. RESULTS: We included 28 patients; 10 were diagnosed with pheochromocytoma and 18 with paraganglioma. Median age at first PRRT was 47 (IQR 15-76) years. The median follow-up time was 31 (IQR 17-37) months. Eight patients died during follow-up. Median OS was 72 months, and 5-year survival was 65% with no difference between pheochromocytoma and paraganglioma. Patients with germline mutations had better survival than patients without mutations (p = 0.041). Median PFS after the first cycle of PRRT was 30 months. For patients who previously received systemic treatment, the median PFS was 19 months, compared with 32 months for patients with no previous systemic treatment (p = 0.083). CONCLUSIONS: The median OS of around 6 years and median PFS of around 2.5 years found in this study are comparable to those reported in previous studies employing PRRT. Based on historical data, the efficacy of PRRT may be superior to 131I-MIBG therapy, and targeted therapy with sunitinib and PRRT might therefore be considered as first-line treatment in this patient group.

Associations Between Glucose Tolerance, Insulin Secretion, Muscle and Fat Mass in Cystic Fibrosis.

BACKGROUND: A frequent comorbidity in cystic fibrosis (CF) is CF related diabetes (CFRD) caused by a gradual decline in insulin secretion. The reduction in the anabolic hormone, insulin, might explain the weight loss that precedes onset of CFRD. We investigated the association between muscle and fat mass in relation to glucose tolerance and insulin function. METHODS: In a cross-sectional study with CF patients (⩾18 years), we conducted an oral glucose tolerance test and dual energy X-ray absorptiometry scan (DXA). Based on plasma glucose, glucose tolerance was defined as normal (NGT): 1-hour <11.1 mmol/L and 2-hour <7.8 mmol/L, impaired (IGT): 2-hour ⩾7.8 and <11.1 mmol/L or CFRD: 2-hour ⩾11.1 mmol/L. Insulin resistance (HOMA-IR) was derived from fasting levels of plasma glucose and plasma insulin, and fat-free and fat mass index (kg/m2) from DXA. Associations were evaluated using linear regression models adjusted for age, sex, and pancreas insufficiency. RESULTS: Among 79 CF patients with exocrine pancreas insufficiency, impairment of glucose tolerance corresponded to reduced insulin secretion. In the IGT group the fat-free mass index (FFMI) was 1.2 kg/m2 (95% CI: [-2.3, -0.03] kg/m2, P = .044) lower compared to the NGT group. FFMI increased insignificantly by 0.4 kg/m2 (95% CI: [-0.6, 1.5] kg/m2, P = .422) among the insulin-treated CFRD group compared to IGT. Fat mass index (FMI) was not different between groups but tended to decrease with glucose tolerance impairment. For each 100 pmol/L increase in fasting insulin FFMI increased by 1.77 kg/m2 (95% CI: [0.21, 3.33] kg/m2/pmol/L/100) and FMI increased by 6.15 kg/m2 (95% CI: [3.87, 8.44] kg/m2/pmol/L/100). In multivariate analyses, HOMA-IR was positively associated with FFMI (ß = 0.5 kg/m2/HOMA-IR, 95% CI: [0.08, 0.92] kg/m2/HOMA-IR, P = .021) and FMI (ß = 1.5 kg/m2/HOMA-IR, 95% CI: [0.87, 2.15] kg/m2/HOMA-IR, P < .001). CONCLUSIONS: Muscle mass was significantly lower among participants with impaired glucose tolerance (IGT), while muscle mass was normalized among those treated with insulin.

Impact of Lean Body Mass and Insulin Sensitivity on the IGF-1-Bone Mass Axis in Adolescence: the EPICOM Study.

CONTEXT: Insulin-like growth factor-1 (IGF-1) is involved in the growth of muscle and bone mass and contributes to glucose homeostasis. The offspring of mothers with diabetes during pregnancy have an increased risk of insulin resistance (IR). OBJECTIVE: We hypothesized that bone mass was decreased in the offspring of mothers with type 1 diabetes (T1D), and that the IGF-1-bone mass relationship would be negatively influenced by IR. DESIGN: Data from the Epigenetic, Genetic and Environmental Effects on Growth, Metabolism and Cognitive Functions in Offspring of Women with Type 1 Diabetes (EPICOM) study performed from 2012 to 2013 were included. SETTING: This work is a follow-up study of a nationwide register study. PATIENTS: A total of 278 adolescent index offspring whose mothers had T1D and 303 matched controls were studied. MAIN OUTCOME MEASURE: Bone mineral content (BMC) determined by a dual-energy x-ray absorptiometry scan and the interaction with IGF-1 and insulin sensitivity were measured. RESULTS: There was no difference in BMC, bone mineral density, height (SD score [SDS]), or BMC/height between index and control offspring. IGF-1 (SDS) did not differ between the groups but insulin-like growth factor-binding protein 3 (SDS) was higher in index boys compared to controls (B = .31 [95% CI, 0.06-0.57], P = .02). The statistical path analysis showed that IGF-1 predicted BMC/height (B = .24 [95% CI, 0.02-0.45], P = .03), but lean mass was a mediator of this. IGF-1 and the homeostatic model assessment of IR were positively associated (B = .75 [95% CI, 0.37-1.12], P < .001). There was no moderating effect of the interaction between IR and IGF-1 on lean mass in the entire cohort (B = .005 [95% CI, -0.03 to 0.04], P = .81) or when analyzing index cases and controls separately. CONCLUSION: We found that lean mass was an intermediary factor in the IGF-1-bone mass relationship in a large cohort of adolescents, and this relationship was not moderated by IR.

Peptide receptor radionuclide therapy in gastroenteropancreatic NEN G3: a multicenter cohort study.

Peptide receptor radionuclide therapy (PRRT) is an established treatment of metastatic neuroendocrine tumors grade 1-2 (G1-G2). However, its possible benefit in high-grade gastroenteropancreatic (GEP) neuroendocrine neoplasms (NEN G3) is largely unknown. We therefore aimed to assess the benefits and side effects of PRRT in patients with GEP NEN G3. We performed a retrospective cohort study at 12 centers to assess the efficacy and toxicity of PRRT in patients with GEP NEN G3. Outcomes were response rate, disease control rate, progression-free survival (PFS), overall survival (OS) and toxicity. We included 149 patients (primary tumor: pancreatic n = 89, gastrointestinal n = 34, unknown n = 26). PRRT was first-line (n = 30), second-line (n = 62) or later-line treatment (n = 57). Of 114 patients evaluated, 1% had complete response, 41% partial response, 38% stable disease and 20% progressive disease. Of 104 patients with documented progressive disease before PRRT, disease control rate was 69%. The total cohort had median PFS of 14 months and OS of 29 months. Ki-67 21-54% (n = 125) vs Ki-67 ≥55% (n = 23): PFS 16 vs 6 months (P < 0.001) and OS 31 vs 9 months (P < 0.001). Well (n = 60) vs poorly differentiated NEN (n = 62): PFS 19 vs 8 months (P < 0.001) and OS 44 vs 19 months (P < 0.001). Grade 3-4 hematological or renal toxicity occurred in 17% of patients. This large multicenter cohort of patients with GEP NEN G3 treated with PRRT demonstrates promising response rates, disease control rates, PFS and OS as well as toxicity in patients with mainly progressive disease. Based on these results, PRRT may be considered for patients with GEP NEN G3.

A randomized double-blind study of testosterone replacement therapy or placebo in testicular cancer survivors with mild Leydig cell insufficiency (Einstein-intervention).

BACKGROUND: Elevated serum levels of luteinizing hormone and slightly decreased serum levels of testosterone (mild Leydig cell insufficiency) is a common hormonal disturbance in testicular cancer (TC) survivors. A number of studies have shown that low serum levels of testosterone is associated with low grade inflammation and increased risk of metabolic syndrome. However, so far, no studies have evaluated whether testosterone substitution improves metabolic dysfunction in TC survivors with mild Leydig cell insufficiency. METHODS/DESIGN: This is a single-center, randomized, double-blind, placebo-controlled study, designed to evaluate the effect of testosterone replacement therapy in TC survivors with mild Leydig cell insufficiency. Seventy subjects will be randomized to receive either testosterone replacement therapy or placebo. The subjects will be invited for an information meeting where informed consent will be obtained. Afterwards, a 52-weeks treatment period begins in which study participants will receive a daily dose of transdermal testosterone or placebo. Dose adjustment will be made three times during the initial 8 weeks of the study to a maximal daily dose of 40 mg of testosterone in the intervention arm. Evaluation of primary and secondary endpoints will be performed at baseline, 26 weeks post-randomization, at the end of treatment (52 weeks) and 3 months after completion of treatment (week 64). DISCUSSION: This study is the first to investigate the effect of testosterone substitution in testicular cancer survivors with mild Leydig cell insufficiency. If positive, it may change the clinical handling of testicular cancer survivors with borderline low levels of testosterone. TRIAL REGISTRATION: ClinicalTrials.gov : NCT02991209 (November 25, 2016).

Preparation and Administration of I-125 Labeled Seeds for Localization of Nonpalpable Breast Lesions.

UNLABELLED: Radioactive seed localization (RSL) is a new technique for surgical identification of non-palpable breast lesions. We describe the preparation of the needle with I-125 seeds for ultrasound-guided deposition in breast lesions. In a feasibility study we investigated the minimum activity amount needed for reliable gamma probe identification of the seeds and the levels of exposure to the staff. METHODS: 11 patients received a seed, which was manually placed in an 18 gauge needle with bone wax occluding the tip, and the radiologist introduced it into the breast tissue guided by ultra-sound. The seed was located during the operation with a handheld gamma probe. The activity amount required was studied in a water bath. Radiation exposure to the fingertips of pathologists was measured by a thermoluminescent dosemeter. RESULTS: All seeds were successfully prepared, positioned in the breast lesion, and easily identified. The surgeon removed the seeds together with the breast lesions, and they were identified by the pathologist. There were no unexpected adverse drug reactions. Water bath studies suggest that 1-3 MBq I-125 was sufficient for precise identification, regardless of the presence of conventional Tc- 99m activity from sentinel node injection. The total finger dose exposure to the pathologists for the 8 procedures was below the detection limit of 0.1 mSv. CONCLUSION: I-125 seeds for ultrasound-guided deployment and surgical identification of breast lesions were successfully prepared and identified for this promising new radioguided surgical technique. The radiation exposure to staff involved is considerably below the permissible limits and almost negligible.

Tumour response after hyperthermic isolated limb perfusion for locally advanced melanoma.

INTRODUCTION: The aim was to describe tumour response, complications, recurrence and survival after hyperthermic isolated limb perfusion (ILP) with melphalan or melphalan in combination with tumour necrosis factor-alpha in patients with melanoma metastases confined to an extremity. MATERIAL AND METHODS: A total of 84 perfusions were performed (53 women, 31 men, median age 63 years) from 1993 to 2010. 95% of the perfusions were administered to the lower limbs and 5% to the upper limbs. The inclusion criteria were recurrent and/or clinically apparent cutaneous/subcutaneous extremity in-transit melanoma metastases. RESULTS: The response rate after ILP was 85%; 42% had complete response (CR), 43% partial response (PR), 12% no change (NC) and 3% progression. Two- and five-year survival rates were 57% and 31%, respectively, and they were higher for patients with than without lymph node metastases. Time from ILP to recurrence was a median of seven months (range 1-37 months) for patients with CR or PR. Survival was longer for patients with CR or PR than for patients showing NC or progression. Several patients had mild or moderate local toxicity reactions, two patients developed severe local toxicity. CONCLUSION: ILP induces tumour regression in the vast majority of patients. One patient, i.e. 1% of the group, died from surgical complications. Otherwise, ILP treatment had an acceptable morbidity in this group of very sick patients. We are convinced that the treatment should be offered to improve local disease control in patients with multiple and/or recurrent melanoma confined to an extremity if surgical excision is not possible. FUNDING: not relevant. TRIAL REGISTRATION: not relevant.

The effect of intravenous PACAP38 on cerebral hemodynamics in healthy volunteers.

PACAP38 is an endogenous peptide located in trigeminal perivascular nerve fibers in the brain. It reduces neuronal loss and infarct size in animal stroke models and has been proposed a candidate substance for human clinical studies of stroke. The effect on systemic hemodynamics and regional cerebral blood flow (rCBF) is not well understood. We here present the first study of the effect of PACAP38 on cerebral hemodynamics in humans. PACAP (10 pmol kg(-1) min(-1)) or placebo (0.9% saline) was infused for 20 min into 12 healthy young volunteers in a cross over, double blind study. rCBF was measured with SPECT and (133)Xe inhalation and mean blood flow velocity in the middle cerebral artery was measured with transcranial Doppler ultrasonography. End tidal partial pressure of CO(2) (P(et)CO(2)) and vital parameters were recorded throughout the 2 hour study period. PACAP38 decreased rCBF in all regions of interest (ROIs) by approximately 3-10%, though not uniformly significant. P(et)CO(2) decreased significantly during PACAP38 infusion compared to placebo (P=0.032), peak decrease was 8.9+/-3.8%. After correction for P(et)CO(2), rCBF remained unchanged in most ROIs. Heart rate increased 61.9+/-22.4% (P<0.0001 vs. placebo). These findings suggest that PACAP38 has no major direct effect on rCBF in healthy volunteers. The marked increase in heart rate and the reduction in rCBF caused by decreased P(et)CO(2) are important dose-limiting factors to consider in future clinical studies.