Case Report: Imaging immune checkpoint inhibitor-induced yin-yang effects in the brain

BackgroundTreatment with immune checkpoint inhibitors (ICI) can induce durable responses in cancer patients, but it is commonly associated with serious immune-related side effects. Both effects are suggested to be mediated by CD8+ T-cell infiltration. Whole body CD8+ T-cell distribution can be visualized by PET imaging of a 89Zr-labeled anti-humanCD8a minibody, currently investigated in a phase 2b trial.Main bodyAn adult patient diagnosed with metastatic melanoma developed ICI-related hypophysitis after two courses of combined immunotherapy (ipilimumab (3 mg/kg) and nivolumab (1 mg/kg) at 3 weeks interval). On a [89Zr]Zr-crefmirlimab berdoxam PET/CT scan, made 8 days before clinical symptoms occurred, increased CD8+ T-cell infiltration in the pituitary gland was detected. Simultaneously, tracer uptake in a cerebral metastasis was increased, indicating ICI-induced tumor infiltration by CD8+ T-cells.ConclusionsThe observations in this case report underscore the role of CD8+ T-cell in non-tumor tissues in ICI-related toxicity. In addition, it illustrates a potential role for molecular imaging by PET/CT for investigation and monitoring of ICI-induced effects

Imaging angiogenesis in patients with head and neck squamous cell carcinomas by [68Ga]Ga-DOTA-E-[c(RGDfK)]2 PET/CT

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¹⁸F-FDG PET/CT Optimizes Treatment in <i>Staphylococcus Aureus</i> Bacteremia and Is Associated with Reduced Mortality.

Metastatic infection is an important complication of Staphylococcus aureus bacteremia (SAB). Early diagnosis of metastatic infection is crucial, because specific treatment is required. However, metastatic infection can be asymptomatic and difficult to detect. In this study, we investigated the role of 18 F-FDG PET/CT in patients with SAB for detection of metastatic infection and its consequences for treatment and outcome. Methods: All patients with SAB at Radboud University Medical Center were included between January 2013 and April 2016. Clinical data and results of 18 F-FDG PET/CT and other imaging techniques, including echocardiography, were collected. Primary outcomes were newly diagnosed metastatic infection by 18 F-FDG PET/CT, subsequent treatment modifications, and patient outcome. Results: A total of 184 patients were included, and 18 F-FDG PET/CT was performed in 105 patients, of whom 99 had a high-risk bacteremia. 18 F-FDG PET/CT detected metastatic infectious foci in 73.7% of these high-risk patients. In 71.2% of patients with metastatic infection, no signs and symptoms suggesting metastatic complications were present before 18 F-FDG PET/CT was performed. 18 F-FDG PET/CT led to a total of 104 treatment modifications in 74 patients. Three-month mortality was higher in high-risk bacteremia patients without 18 F-FDG PET/CT performed than in those in whom 18 F-FDG PET/CT was performed (32.7% vs. 12.4%, P = 0.003). In multivariate analysis, 18 F-FDG PET/CT was the only factor independently associated with reduced mortality ( P = 0.005; odds ratio, 0.204; 95% confidence interval, 0.066-0.624). A higher comorbidity score was independently associated with increased mortality ( P = 0.003; odds ratio, 1.254; 95% confidence interval, 1.078-1.457). Conclusion: 18 F-FDG PET/CT is a valuable technique for early detection of metastatic infectious foci, often leading to treatment modification. Performing 18 F-FDG PET/CT is associated with significantly reduced 3-mo mortality

A comparison of the diagnostic value of MRI and ¹⁸F-FDG-PET/CT in suspected spondylodiscitis.

Purpose The purpose of this study was to evaluate the diagnostic value of 18F-fluorodeoxyglucose (FDG) positron emission tomography and computed tomography (PET/CT scan) and magnetic resonance imaging (MRI) in diagnosing spondylodiscitis and its complications, such as epidural and paraspinal abscesses.Methods From January 2006 to August 2013 patients with a clinical suspicion of spondylodiscitis, with an infection, or with fever of unknown origin were retrospectively included if 18F-FDG-PET/CT and MRI of the spine were performed within a 2-week time span. Imaging results were compared to the final clinical diagnosis and follow-up data were collected.Results Sixty-eight patients were included of whom 49 patients were diagnosed with spondylodiscitis. MRI showed an overall sensitivity of 67 % and specificity of 84 %. Diagnostic accuracy was 58 %, when MRI was performed within 2 weeks after the start of symptoms and improved to 82 %, when performed more than 2 weeks after onset of symptoms. 18F-FDG-PET/CT showed a sensitivity of 96 % and a specificity of 95 %, with no relation to the interval between the scan and the start of symptoms.Conclusions As compared to MRI, 18F-FDG-PET/CT has superior diagnostic value for detecting early spondylodiscitis. After 2 weeks both techniques perform similarly

A pilot study on the immunogenicity of dendritic cell vaccination during adjuvant oxaliplatin/capecitabine chemotherapy in colon cancer patients

Contains fulltext : 87604.pdf (publisher's version ) (Closed access)BACKGROUND: Dendritic cell (DC) vaccination has been shown to induce anti-tumour immune responses in cancer patients, but so far its clinical efficacy is limited. Recent evidence supports an immunogenic effect of cytotoxic chemotherapy. Pre-clinical data indicate that the combination of chemotherapy and immunotherapy may result in an enhanced anti-cancer activity. Most studies have focused on the immunogenic aspect of chemotherapy-induced cell death, but only few studies have investigated the effect of chemotherapeutic agents on the effector lymphocytes of the immune system. METHODS: Here we investigated the effect of treatment with oxaliplatin and capecitabine on non-specific and specific DC vaccine-induced adaptive immune responses. Stage III colon cancer patients receiving standard adjuvant oxaliplatin/capecitabine chemotherapy were vaccinated at the same time with keyhole limpet haemocyanin (KLH) and carcinoembryonic antigen (CEA)-peptide pulsed DCs. RESULTS: In 4 out of 7 patients, functional CEA-specific T-cell responses were found at delayed type hypersensitivity (DTH) skin testing. In addition, we observed an enhanced non-specific T-cell reactivity upon oxaliplatin administration. KLH-specific T-cell responses remained unaffected by the chemotherapy, whereas B-cell responses were diminished. CONCLUSION: The results strongly support further testing of the combined use of specific anti-tumour vaccination with oxaliplatin-based chemotherapy

Dendritic cell vaccination and immune monitoring

We exploited dendritic cells (DC) to vaccinate melanoma patients. We recently demonstrated a statistical significant correlation between favorable clinical outcome and the presence of vaccine-related tumor antigen-specific T cells in delayed type hypersensitivity (DTH) skin biopsies. However, favorable clinical outcome is only observed in a minority of the treated patients. Therefore, it is obvious that current DC-based protocols need to be improved. For this reason, we study in small proof of principle trials the fate, interactions and effectiveness of the injected DC

Maturation of monocyte-derived dendritic cells with Toll-like receptor 3 and 7/8 ligands combined with prostaglandin E2 results in high interleukin-12 production and cell migration

Dendritic cells (DC) are professional antigen-presenting cells of the immune system that play a key role in regulating T cell-based immunity. In vivo, the capacity of DC to activate T cells depends on their ability to migrate to the T cell areas of lymph nodes as well as on their maturation state. Depending on their cytokine-secreting profile, DC are able to skew the immune response in a specific direction. In particular, IL-12p70 producing DC drive T cells towards a T helper 1 type response. A serious disadvantage of current clinical grade ex vivo generated monocyte-derived DC is the poor IL-12p70 production. We have investigated the effects of Toll-like receptor (TLR)-mediated maturation on ex vivo generated human monocyte-derived DC. We demonstrate that in contrast to cytokine-matured DC, DC matured with poly(I:C) (TLR3 ligand) and/or R848 (TLR7/8 ligand) are able to produce vast amounts of IL-12p70, but exhibit a reduced migratory capacity. The addition of prostaglandin E2 (PGE2) improved the migratory capacity of TLR-ligand matured DC while maintaining their IL-12p70 production upon T cell encounter. We propose a novel clinical grade maturation protocol in which TLR ligands poly(I:C) and R848 are combined with PGE2 to generate DC with both high migratory capacity and IL-12p70 production upon T cell encounter

Dendritic cells in cancer immunology and immunotherapy

Dendritic cells (DCs) are a diverse group of specialized antigen-presenting cells with key roles in the initiation and regulation of innate and adaptive immune responses. As such, there is currently much interest in modulating DC function to improve cancer immunotherapy. Many strategies have been developed to target DCs in cancer, such as the administration of antigens with immunomodulators that mobilize and activate endogenous DCs, as well as the generation of DC-based vaccines. A better understanding of the diversity and functions of DC subsets and of how these are shaped by the tumour microenvironment could lead to improved therapies for cancer. Here we will outline how different DC subsets influence immunity and tolerance in cancer settings and discuss the implications for both established cancer treatments and novel immunotherapy strategies.S.K.W. is supported by a European Molecular Biology Organization Long- Term Fellowship (grant ALTF 438– 2016) and a CNIC–International Postdoctoral Program Fellowship (grant 17230–2016). F.J.C. is the recipient of a PhD ‘La Caixa’ fellowship. Work in the D.S. laboratory is funded by the CNIC, by the European Research Council (ERC Consolidator Grant 2016 725091), by the European Commission (635122-PROCROP H2020), by the Ministerio de Ciencia, Innovación e Universidades (MCNU), Agencia Estatal de Investigación and Fondo Europeo de Desarrollo Regional (FEDER) (SAF2016-79040-R), by the Comunidad de Madrid (B2017/BMD-3733 Immunothercan- CM), by FIS- Instituto de Salud Carlos III, MCNU and FEDER (RD16/0015/0018-REEM), by Acteria Foundation, by Atresmedia (Constantes y Vitales prize) and by Fundació La Marató de TV3 (201723). The CNIC is supported by the Instituto de Salud Carlos III, the MCNU and the Pro CNIC Foundation, and is a Severo Ochoa Centre of Excellence (SEV-2015-0505).S

Lesion detection by [Zr-89]Zr-DFO-girentuximab and [F-18]FDG-PET/CT in patients with newly diagnosed metastatic renal cell carcinoma

PURPOSE: The main objective of this preliminary analysis of the IMaging PAtients for Cancer drug selecTion (IMPACT)-renal cell cancer (RCC) study is to evaluate the lesion detection of baseline contrast-enhanced CT, [89Zr]Zr-DFO-girentuximab-PET/CT and [18F]FDG-PET/CT in detecting ccRCC lesions in patients with a good or intermediate prognosis metastatic clear cell renal cell carcinoma (mccRCC) according to the International Metastatic Database Consortium (IMDC) risk model. METHODS: Between February 2015 and March 2018, 42 newly diagnosed mccRCC patients with good or intermediate prognosis, eligible for watchful waiting, were included. Patients underwent CT, [89Zr]Zr-DFO-girentuximab-PET/CT and [18F]FDG-PET/CT at baseline. Scans were independently reviewed and lesions of ≥10 mm and lymph nodes of ≥15 mm at CT were analyzed. For lesions with [89Zr]Zr-DFO-girentuximab or [18F]FDG-uptake visually exceeding background uptake, maximum standardized uptake values (SUVmax) were measured. RESULTS: A total of 449 lesions were detected by ≥1 modality (median per patient: 7; ICR 4.25-12.75) of which 42% were in lung, 22% in lymph nodes and 10% in bone. Combined [89Zr]Zr-DFO-girentuximab-PET/CT and CT detected more lesions than CT alone: 91% (95%CI: 87-94) versus 56% (95%CI: 50-62, p = 0.001), respectively, and more than CT and [18F]FDG-PET/CT combined (84% (95%CI:79-88, p < 0.005). Both PET/CTs detected more bone and soft tissue lesions compared to CT alone. CONCLUSIONS: The addition of [89Zr]Zr-DFO-girentuximab-PET/CT and [18F]FDG-PET/CT to CT increases lesion detection compared to CT alone in newly diagnosed good and intermediate prognosis mccRCC patients eligible for watchful waiting