Epigenetic landscape reorganization and reactivation of embryonic development genes are associated with malignancy in IDH-mutant astrocytoma.

Accurate grading of IDH-mutant gliomas defines patient prognosis and guides the treatment path. Histological grading is however difficult and, apart from CDKN2A/B homozygous deletions in IDH-mutant astrocytomas, there are no other objective molecular markers used for grading. Experimental Design: RNA-sequencing was conducted on primary IDH-mutant astrocytomas (n=138) included in the prospective CATNON trial, which was performed to assess the prognostic effect of adjuvant and concurrent temozolomide. We integrated the RNA sequencing data with matched DNA-methylation and NGS data. We also used multi-omics data from IDH-mutant astrocytomas included in the TCGA dataset and validated results on matched primary and recurrent samples from the GLASS-NL study. We used the DNA-methylation profiles to generate a Continuous Grading Coefficient (CGC) that is based on classification scores derived from a CNS-tumor classifier. We found that the CGC was an independent predictor of survival outperforming current WHO-CNS5 and methylation-based classification. Our RNA-sequencing analysis revealed four distinct transcription clusters that were associated with i) an upregulation of cell cycling genes; ii) a downregulation of glial differentiation genes; iii) an upregulation of embryonic development genes (e.g. HOX, PAX and TBX) and iv) an upregulation of extracellular matrix genes. The upregulation of embryonic development genes was associated with a specific increase of CpG island methylation near these genes.

Molecular analysis using SalvGlandDx improves risk of malignancy estimation and diagnosis of salivary gland cytopathology: An exploratory multicenter study.

BACKGROUND: Diagnosis of salivary gland neoplasms is challenging, especially on cytological specimens acquired by fine-needle aspiration. The recently implemented standardized Milan system for reporting salivary gland cytopathology provides an estimated risk of malignancy (ROM); yet, for two of the categories, the diagnosis of the lesion remains unclear. However, a precise diagnosis is desirable for optimal patient management, including planning of surgery and imaging procedures. METHODS: Cytological specimens (n = 106) were subjected to molecular analysis using the SalvGlandDx panel. The risk of malignancy was calculated for each detected alteration based on the diagnosis of the resection specimen. By taking into account the molecular alterations, their associated ROM, the clinical and cytological features, and the current literature, the Milan category was evaluated. RESULTS: Of n = 63 technically valid cases, 76% revealed a molecular alteration. A total of 94% of these molecularly altered cases could be assigned to a different Milan category when additionally taking molecular results into account. In only 2% of the salivary gland neoplasms of uncertain malignant potential, in which a molecular alteration was detected, the classification remained salivary gland neoplasms of uncertain malignant potential. CONCLUSION: Molecular analysis of cytological specimens provides a benefit in classifying salivary gland neoplasms on fine-needle aspiration. It can improve the ROM estimation and thus help to assign cases of formerly unknown malignant potential to clearly benign or malignant categories.

CD4+ T cell activation distinguishes response to anti-PD-L1+anti-CTLA4 therapy from anti-PD-L1 monotherapy.

Cancer patients often receive a combination of antibodies targeting programmed death-ligand 1 (PD-L1) and cytotoxic T lymphocyte antigen-4 (CTLA4). We conducted a window-of-opportunity study in head and neck squamous cell carcinoma (HNSCC) to examine the contribution of anti-CTLA4 to anti-PD-L1 therapy. Single-cell profiling of on- versus pre-treatment biopsies identified T cell expansion as an early response marker. In tumors, anti-PD-L1 triggered the expansion of mostly CD8+ T cells, whereas combination therapy expanded both CD4+ and CD8+ T cells. Such CD4+ T cells exhibited an activated T helper 1 (Th1) phenotype. CD4+ and CD8+ T cells co-localized with and were surrounded by dendritic cells expressing T cell homing factors or antibody-producing plasma cells. T cell receptor tracing suggests that anti-CTLA4, but not anti-PD-L1, triggers the trafficking of CD4+ naive/central-memory T cells from tumor-draining lymph nodes (tdLNs), via blood, to the tumor wherein T cells acquire a Th1 phenotype. Thus, CD4+ T cell activation and recruitment from tdLNs are hallmarks of early response to anti-PD-L1 plus anti-CTLA4 in HNSCC.

The prognostic effect of radiological extranodal extension in HPV-positive oropharyngeal squamous cell carcinomas: a retrospective cohort analysis.

PURPOSE: Radiological extranodal extension (rENE) is a well-known negative prognosticator in head and neck squamous cell carcinoma (HNSCC). However, controversy remains regarding the prognostic effect of rENE in HPV-positive oropharyngeal SCCs (OPSCC). This single-center retrospective cohort analysis assessed the prognostic role of rENE in an HPV + OPSCC population and tried to validate a recently proposed modification of the TNM8 N-classification. METHODS: 129 patients with HPV + OPSCC, of whom 106 cN + patients, were included. Radiological imaging (CT, MRI or both) was reanalyzed by a senior head and neck radiologist. Overall survival (OS), disease-free survival (DFS), locoregional recurrence-free survival (LRFS), and disease-specific survival (DSS) were evaluated. Cox proportional hazard models were used for estimating hazard ratios (HR). RESULTS: A non-significant trend towards better outcomes in the rENE- group, as compared to the rENE + population, was observed for 5 year OS [80.99% vs 68.70%, HR: 2.05, p = 0.160], 5 year RFS [78.81% vs 67.87%, HR: 1.91, p = 0.165], 5 year DFS [77.06% vs 60.16%, HR: 2.12, p = 0.0824] and 5 year DSS [88.83% vs 81.93%, HR: 2.09, p = 0.195]. OS declined with ascending levels of rENE (p = 0.020). Multivariate analysis identified cT-classification and smoking as independent negative predictors for OS/DFS. The proposed modification of the TNM8 N-classification could not be validated. CONCLUSIONS: Although rENE could not be identified as an independent negative prognosticator for outcome in our HPV + OPSCC population, outcomes tend to deteriorate with increasing rENE.

Exploring long-term responses to immune checkpoint inhibitors in recurrent and metastatic head and neck squamous cell carcinoma.

OBJECTIVES: Immune checkpoint inhibitors (ICI) have introduced a new era in the treatment of recurrent and/or metastatic head and neck squamous cell carcinoma (R/M HNSCC). Optimal duration for ICI therapy is still unclear and the long-term outcomes and toxicity in patients responding to these therapies warrant further exploration. This study attempts to identify the clinical and biological determinants of a durable response and evaluate outcomes following ICI treatment discontinuation. MATERIALS AND METHODS: A retrospective review of 181 patients treated with ICI for R/M HNSCC was conducted. Long-term responders were defined as patients who sustained disease control at least two years after initiating ICI therapy. We compared clinical and biological characteristics associated with these long-term responders against the broader treatment population. RESULTS: 10 % of R/M HNSCC patients treated with ICIs demonstrated a durable long-term response. Only three relapses (16 %) occurred after discontinuing ICI treatment in this subset, with a median follow-up of 52 months. Upon retreatment with ICI, two attained a documented response. Extended ICI response was observed even with < 2 years of treatment. 74 % of long-term responders experienced immune-related adverse events (irAEs), 37 % of which severe irAEs. Hypothyroidism was the most frequently reported irAEs. The predictive potential of systemic inflammation indices for clinical response appears to be limited. CONCLUSIONS: ICI present an optimistic avenue for HNSCC patients, offering substantial long-term responses. The study suggests that a two-year treatment could be optimal and irAEs, although common, are typically mild.

Intra-individual qualitative and quantitative comparison of [68Ga]Ga-DOTATATE PET/CT and PET/MRI.

Background: Somatostatin receptor (SSTR) positron emission tomography (PET) is a cornerstone of neuroendocrine tumor (NET) management. Hybrid PET/magnetic resonance imaging (MRI) is now available for NET-imaging, next to PET/computed tomography (CT). Objectives: To determine whether CT or MRI is the best hybrid partner for [68Ga]Ga-DOTATATE PET. Design: Monocentric, prospective study. Methods: Patients received a same-day [68Ga]Ga-DOTATATE PET/CT and subsequent PET/MRI, for suspicion of NET, (re)staging or peptide receptor radionuclide therapy-selection. The union (PETunion) of malignant lesions detected on PETCT and PETMRI was the reference standard. Concordance of detection of malignant lesions in an organ was measured between PETunion and CT and PETunion and MRI. Seven bins were used to categorize the number of malignant lesions, containing following ordinal variables: 0, 1, 2-5, 6-10, 11-20, >20 countable and diffuse/uncountable. The difference in number of malignant lesions was obtained as the difference in bin level ('Δbin') between PETunion and CT and PETunion and MRI with a Δbin closer to zero implying a higher concordance rate. Results: Twenty-nine patients were included. Primary tumors included 17 gastroenteropancreatic-NETs, 1 colon neuroendocrine carcinoma, 7 lung-NETs and 2 meningiomas. Patient level concordance with PETunion was 96% for MRI and 67% for CT (p = 0.039). Organ level concordance with PETunion was 74% for MRI and 40% for CT (p < 0.0001). In bone, there was a higher concordance rate for MRI compared to CT, 92% and 33%, respectively (p = 0.016). Overall, a mean Δbin of 0.5 ± 1.1 for PETunion/MRI and 1.4 ± 1.2 for PETunion/CT (p < 0.0001) was noted. In liver, a mean Δbin of 0.0 ± 1.1 for PETunion/MRI and 1.7 ± 1.2 for PETunion/CT was observed (p = 0.0078). In bone, a mean Δbin closer to zero was observed for PETunion/MRI compared to PETunion/CT, 0.6 ± 1.4 and 2.0 ± 1.5, respectively (p = 0.0098). Conclusions: Compared to SSTR PET/CT, SSTR PET/MRI had a higher patient and organ level concordance for malignant tumoral involvement and number of malignant lesions, with a clear added value in bone and liver specifically.

Tumor Microenvironment Modifications Induced by Afatinib in Squamous Cell Carcinoma of the Head and Neck: A Window-of-Opportunity Study (EORTC-90111-24111).

PURPOSE: The EORTC-90111-24111 phase II window study evaluated afatinib versus no preoperative treatment in patients with primary squamous cell carcinoma of the head and neck (HNSCC). We investigated afatinib-induced tumor and microenvironment modifications by comparing pre- and posttreatment tumor biopsies. PATIENTS AND METHODS: Thirty treatment-naïve patients with primary HNSCC were randomized. Twenty-five patients received afatinib for 14 days before surgery (40 mg 1×/day) and 5 patients were attributed to the control arm. Biopsies were taken at work-up and during surgery. Good quality RNA samples were used for omics analyses. The control arm was enlarged by samples coming from our previous similar window study. RESULTS: IHC analyses of afatinib-treated tumor biopsies showed a decrease in pEGFR (P ≤ 0.05) and pERK (P ≤ 0.05); and an increase in CD3+ (P ≤ 0.01) and CD8+ (P ≤ 0.01) T-cell infiltration, and in CD3+ (P ≤ 0.05) T-cell density. RNA sequencing analyses of afatinib-treated tumor samples showed upregulation of inflammatory genes and increased expression scores of signatures predictive of response to programmed cell death protein 1 blockade (P ≤ 0.05). In posttreatment biopsies of afatinib-treated patients, two clusters were observed. Cluster 1 showed a higher expression of markers and gene sets implicated in epithelial-to-mesenchymal transition (EMT) and activation of cancer-associated fibroblasts (CAF) compared with cluster 2 and controls. CONCLUSIONS: Short-term treatment with afatinib in primary HNSCC induces CD3+ and CD8+ tumor infiltration and, in some patients, EMT and CAF activation. These results open perspectives to overcome resistance mechanisms to anti-HER therapy and to potentiate the activity of immune checkpoint inhibitors.

Prognostic Markers of DNA Methylation and Next-Generation Sequencing in Progressive Glioblastoma from the EORTC-26101 Trial.

PURPOSE: The EORTC-26101 study was a randomized phase II and III clinical trial of bevacizumab in combination with lomustine versus lomustine alone in progressive glioblastoma. Other than for progression-free survival (PFS), there was no benefit from addition of bevacizumab for overall survival (OS). However, molecular data allow for the rare opportunity to assess prognostic biomarkers from primary surgery for their impact in progressive glioblastoma. EXPERIMENTAL DESIGN: We analyzed DNA methylation array data and panel sequencing from 170 genes of 380 tumor samples of the EORTC-26101 study. These patients were comparable with the overall study cohort in regard to baseline characteristics, study treatment, and survival. RESULTS: Of patients' samples, 295/380 (78%) were classified into one of the main glioblastoma groups, receptor tyrosine kinase (RTK)1, RTK2 and mesenchymal. There were 10 patients (2.6%) with isocitrate dehydrogenase mutant tumors in the biomarker cohort. Patients with RTK1 and RTK2 classified tumors had lower median OS compared with mesenchymal (7.6 vs. 9.2 vs. 10.5 months). O6-methylguanine DNA-methyltransferase (MGMT) promoter methylation was prognostic for PFS and OS. Neurofibromin (NF)1 mutations were predictive of response to bevacizumab treatment. CONCLUSIONS: Thorough molecular classification is important for brain tumor clinical trial inclusion and evaluation. MGMT promoter methylation and RTK1 classifier assignment were prognostic in progressive glioblastoma. NF1 mutation may be a predictive biomarker for bevacizumab treatment.

Health-related quality-of-life results from the randomised phase II TAVAREC trial on temozolomide with or without bevacizumab in 1p/19q intact first-recurrence World Health Organization grade 2 and 3 glioma (European Organization for Research and Treatment of Cancer 26091).

BACKGROUND: In an international randomised controlled phase II study of temozolomide (TMZ) versus TMZ in combination with bevacizumab (BEV) in locally diagnosed non-1p/19q co-deleted World Health Organization grade 2 or 3 gliomas with a first and contrast-enhancing recurrence after initial radiotherapy, and overall survival at 12 months was not significantly different (61% in the TMZ arm and 55% in the TMZ + BEV arm). OBJECTIVES: Health-related quality of life (HRQoL) was a key secondary end-point in this trial, and the main objective of this study was to determine the impact of the addition of BEV to TMZ on HRQoL. METHODS: HRQoL was assessed using the European Organization for Research and Treatment of Cancer QLQ-C30 (version 3) and QLQ-BN20 at baseline, and then every 12 weeks until disease progression. The pre-selected primary HRQoL end-point was the QLQ-C30 global health scale, with self-perceived cognitive functioning and pain selected as secondary HRQoL issues. Analysis was undertaken using linear mixed modelling and complemented with sensitivity analyses using summary statistics. A difference was considered clinically relevant with ≥10 points difference on a 100-point scale. RESULTS: Baseline compliance was high at 94% and remained above 60% until 72 weeks, limiting the analysis to 60 weeks. Compliance was similar in both arms. We found no statistically significant or clinically significant differences between the primary HRQoL end-point in both treatment arms (p = 0.2642). The sensitivity analyses confirmed this finding. The overall test for post-baseline differences between the two treatment arms also showed no statistically or clinically significant differences regarding the selected secondary end-point scales. INTERPRETATION: The addition of BEV to TMZ in this patient group neither improves nor negatively impacts HRQoL.

Trial watch: chemotherapy-induced immunogenic cell death in oncology.

Immunogenic cell death (ICD) refers to an immunologically distinct process of regulated cell death that activates, rather than suppresses, innate and adaptive immune responses. Such responses culminate into T cell-driven immunity against antigens derived from dying cancer cells. The potency of ICD is dependent on the immunogenicity of dying cells as defined by the antigenicity of these cells and their ability to expose immunostimulatory molecules like damage-associated molecular patterns (DAMPs) and cytokines like type I interferons (IFNs). Moreover, it is crucial that the host's immune system can adequately detect the antigenicity and adjuvanticity of these dying cells. Over the years, several well-known chemotherapies have been validated as potent ICD inducers, including (but not limited to) anthracyclines, paclitaxels, and oxaliplatin. Such ICD-inducing chemotherapeutic drugs can serve as important combinatorial partners for anti-cancer immunotherapies against highly immuno-resistant tumors. In this Trial Watch, we describe current trends in the preclinical and clinical integration of ICD-inducing chemotherapy in the existing immuno-oncological paradigms.

Prospective comparison of [18F]AlF-NOTA-octreotide PET/MRI to [68Ga]Ga-DOTATATE PET/CT in neuroendocrine tumor patients.

BACKGROUND: Fluorine-18-labeled SSAs have the potential to become the next-generation tracer in SSTR-imaging in neuroendocrine tumor (NET) patients given their logistical advantages over the current gold standard gallium-68-labeled SSAs. In particular, [18F]AlF-OC has already shown excellent clinical performance. We demonstrated in our previous report from our prospective multicenter trial that [18F]AlF-OC PET/CT outperforms [68Ga]Ga-DOTA-SSA, but histological confirmation was lacking due to ethical and practical reasons. In this second arm, we therefore aimed to provide evidence that the vast majority of [18F]AlF-OC PET lesions are in fact true NET lesions by analyzing their MR characteristics on simultaneously acquired MRI. We had a special interest in lesions solely detected by [18F]AlF-OC ("incremental lesions"). METHODS: Ten patients with a histologically confirmed neuroendocrine tumor (NET) and a standard-of-care [68Ga]Ga-DOTATATE PET/CT, performed within 3 months, were prospectively included. Patients underwent a whole-body PET/MRI (TOF, 3 T, GE Signa), 2 hours after IV injection of 4 MBq/kg [18F]AlF-OC. Positive PET lesions were evaluated for a corresponding lesion on MRI. The diagnostic performance of both PET tracers was evaluated by determining the detection ratio (DR) for each scan and the differential detection ratio (DDR) per patient. RESULTS: In total, 195 unique lesions were detected: 167 with [68Ga]Ga-DOTATATE and 193 with [18F]AlF-OC. The DR for [18F]AlF-OC was 99.1% versus 91.4% for [68Ga]Ga-DOTATATE, significant for non-inferiority testing (p = 0.0001). Out of these 193 [18F]AlF-OC lesions, 96.2% were confirmed by MRI to be NET lesions. Thirty-three incremental lesions were identified by [18F]AlF-OC, of which 91% were confirmed by MRI and considered true positives. CONCLUSION: The DR of [18F]AlF-OC was numerically higher and non-inferior to the DR of [68Ga]Ga-DOTATATE. [18F]AlF-OC lesions and especially incremental lesions were confirmed as true positives by MRI in more than 90% of lesions. Taken together, these data further validate [18F]AlF-OC as a new alternative for SSTR PET in clinical practice. Trial registration ClinicalTrials.gov: NCT04552847. Registered 17 September 2020, https://beta. CLINICALTRIALS: gov/study/NCT04552847.

Single-cell molecular profiling using ex vivo functional readouts fuels precision oncology in glioblastoma.

BACKGROUND: Functional profiling of freshly isolated glioblastoma (GBM) cells is being evaluated as a next-generation method for precision oncology. While promising, its success largely depends on the method to evaluate treatment activity which requires sufficient resolution and specificity. METHODS: Here, we describe the 'precision oncology by single-cell profiling using ex vivo readouts of functionality' (PROSPERO) assay to evaluate the intrinsic susceptibility of high-grade brain tumor cells to respond to therapy. Different from other assays, PROSPERO extends beyond life/death screening by rapidly evaluating acute molecular drug responses at single-cell resolution. RESULTS: The PROSPERO assay was developed by correlating short-term single-cell molecular signatures using mass cytometry by time-of-flight (CyTOF) to long-term cytotoxicity readouts in representative patient-derived glioblastoma cell cultures (n = 14) that were exposed to radiotherapy and the small-molecule p53/MDM2 inhibitor AMG232. The predictive model was subsequently projected to evaluate drug activity in freshly resected GBM samples from patients (n = 34). Here, PROSPERO revealed an overall limited capacity of tumor cells to respond to therapy, as reflected by the inability to induce key molecular markers upon ex vivo treatment exposure, while retaining proliferative capacity, insights that were validated in patient-derived xenograft (PDX) models. This approach also allowed the investigation of cellular plasticity, which in PDCLs highlighted therapy-induced proneural-to-mesenchymal (PMT) transitions, while in patients' samples this was more heterogeneous. CONCLUSION: PROSPERO provides a precise way to evaluate therapy efficacy by measuring molecular drug responses using specific biomarker changes in freshly resected brain tumor samples, in addition to providing key functional insights in cellular behavior, which may ultimately complement standard, clinical biomarker evaluations.

18F-AlF-NOTA-Octreotide Outperforms 68Ga-DOTATATE/NOC PET in Neuroendocrine Tumor Patients: Results from a Prospective, Multicenter Study.

18F-labeled somatostatin analogs (SSAs) could represent a valid alternative to the current gold standard, 68Ga-labeled SSAs, for somatostatin receptor imaging in patients with neuroendocrine tumors (NETs), given their logistic advantages. Recently, 18F-AlF-NOTA-octreotide (18F-AlF-OC) has emerged as a promising candidate, but a thorough comparison with 68Ga-DOTA-SSA in large patient groups is needed. This prospective, multicenter trial aims to demonstrate noninferiority of 18F-AlF-OC compared with 68Ga-DOTA-SSA PET in NET patients (ClinicalTrials.gov, NCT04552847). Methods: Seventy-five patients with histologically confirmed NET and routine clinical 68Ga-DOTATATE (n = 56) or 68Ga-DOTANOC (n = 19) PET, performed within a 3-mo interval of the study scan (median, 7 d; range, -30 to +32 d), were included. Patients underwent a whole-body PET 2 h after intravenous injection of 4 MBq/kg of 18F-AlF-OC. A randomized, masked consensus read was performed by 2 experienced readers to count tumor lesions. After unmasking, the detection ratio (DR) was determined for each scan, that is, the fraction of lesions detected on a scan compared with the union of lesions of both scans. The differential DR (DDR; difference in DR between 18F-AlF-OC and 68Ga-DOTATATE/NOC) per patient was calculated. Tracer uptake was evaluated by comparing SUVmax and tumor-to-background ratios in concordant lesions. Results: In total, 4,709 different tumor lesions were detected: 3,454 with 68Ga-DOTATATE/NOC and 4,278 with 18F-AlF-OC. The mean DR with 18F-AlF-OC was significantly higher than with 68Ga-DOTATATE/NOC (91.1% vs. 75.3%; P < 10-5). The resulting mean DDR was 15.8%, with a lower margin of the 95% CI (95% CI, 9.6%-22.0%) higher than -15%, which is the prespecified boundary for noninferiority. The mean DDRs for the 68Ga-DOTATATE and 68Ga-DOTANOC subgroups were 11.8% (95% CI, 4.3-19.3) and 27.5% (95% CI, 17.8-37.1), respectively. The mean DDR for most organs was higher than zero, except for bone lesions (mean DDR, -2.8%; 95% CI, -17.8 to 12.2). No significant differences in mean SUVmax were observed (P = 0.067), but mean tumor-to-background ratio was significantly higher with 18F-AlF-OC than with 68Ga-DOTATATE/NOC (31.7 ± 36.5 vs. 25.1 ± 32.7; P = 0.001). Conclusion: 18F-AlF-OC is noninferior and even superior to 68Ga-DOTATATE/NOC PET in NET patients. This validates 18F-AlF-OC as an option for clinical practice somatostatin receptor PET.

The predictive and prognostic value of weight loss and body composition prior to and during immune checkpoint inhibition in recurrent or metastatic head and neck cancer patients.

BACKGROUND: Response rates of immune checkpoint inhibitor (ICI) therapy for recurrent and/or metastatic head and neck squamous cell carcinoma (R/M HNSCC) are low. PATIENTS AND METHODS: This retrospective multicentre cohort study evaluates the predictive and prognostic value of weight loss and changes in body composition prior and during therapy. Patient, tumor, and treatment characteristics of 98 patients were retrieved, including neutrophil and platelet-lymphocyte-ratio (NLR and PLR). Programmed death-ligand 1 (PD-L1) expression was determined on residual material. Cachexia was defined according to Fearon et al. (2011). Skeletal muscle (SM), visceral adipose tissue (VAT), and subcutaneous adipose tissue (SAT) were evaluated on computed tomography scans at the third lumbar vertebrae level. Univariable and multivariable regression analyses were performed for 6 months progression free survival (PFS6m) and overall survival (OS). RESULTS: Significant early weight loss (>2%) during the first 6 weeks of therapy was shown in 34 patients (35%). This patient subgroup had a significantly higher NLR and PLR at baseline. NLR and PLR were inversely correlated with SM and VAT index. Independent predictors of PFS6m were lower World Health Organization performance status (HR 0.16 [0.04-0.54] p = 0.003), higher baseline SAT index (HR 1.045 [1.02-1.08] p = 0.003), and weight loss <2% (HR 0.85 [0.74-0.98] p = 0.03). Baseline cachexia in combination with >2% early weight loss remained a predictor of OS, independent of PD-L1 expression (HR 2.09 [1.11-3.92] p = 0.02, HR 2.18 [1.13-4.21] p = 0.02). CONCLUSION: We conclude that the combination of cachexia at baseline and weight loss during ICI therapy is associated with worse OS in R/M HNSCC patients, independent of PD-L1 expression.

[18F] MFBG PET imaging: biodistribution, pharmacokinetics, and comparison with [123I] MIBG in neural crest tumour patients.

PURPOSE: Despite its limitations, [123I]MIBG scintigraphy has been the standard for human norepinephrine transporter (hNET) imaging for several decades. Recently, [18F]MFBG has emerged as a promising PET alternative. This prospective trial aimed to evaluate safety, biodistribution, tumour lesion pharmacokinetics, and lesion targeting of [18F]MFBG and perform a head-to-head comparison with [123I]MIBG in neural crest tumour patients. METHODS: Six neural crest tumour patients (4 phaeochromocytoma, 1 paraganglioma, 1 neuroblastoma) with a recent routine clinical [123I]MIBG scintigraphy (interval: - 37-75 days) were included. Adult patients (n = 5) underwent a 30-min dynamic PET, followed by 3 whole-body PET/CT scans at 60, 120, and 180 min after injection of 4 MBq/kg [18F]MFBG. One minor participant underwent a single whole-body PET/CT at 60 min after administration of 2 MBq/kg [18F]MFBG. Normal organ uptake (SUVmean) and lesion uptake (SUVmax; tumour-to-background ratio (TBR)) were measured. Regional distribution volumes (VT) were estimated using a Logan graphical analysis in up to 6 lesions per patient. A lesion-by-lesion analysis was performed to compare detection ratios (DR), i.e. fraction of detected lesions, between [18F]MFBG and [123I]MIBG. RESULTS: [18F]MFBG was safe and well tolerated. Its biodistribution was overall similar to that of [123I]MIBG, with prominent uptake in the salivary glands, liver, left ventricle wall and adrenals, and mainly urinary excretion. In the phaeochromocytoma subgroup, the median VT was 37.4 mL/cm3 (range: 18.0-144.8) with an excellent correlation between VT and SUVmean at all 3 time points (R2: 0.92-0.94). Mean lesion SUVmax and TBR at 1 h after injection were 19.3 ± 10.7 and 23.6 ± 8.4, respectively. All lesions detected with [123I]MIBG were also observed with [18F]MFBG. The mean DR with [123I]MIBG was significantly lower than with [18F]MFBG (61.0% ± 26.7% vs. 99.8% ± 0.5% at 1 h; p = 0.043). CONCLUSION: [18F]MFBG is a promising hNET imaging agent with favourable imaging characteristics and improved lesion targeting compared with [123I]MIBG scintigraphy. TRIAL REGISTRATION: Clinicaltrials.gov : NCT04258592 (Registered: 06 February 2020), EudraCT: 2019-003872-37A.

Thrombocytopenia limits the feasibility of salvage lomustine chemotherapy in recurrent glioblastoma: a secondary analysis of EORTC 26101.

BACKGROUND: Thrombocytopenia represents the main cause of stopping alkylating chemotherapy for toxicity. Here, we explored the incidence, and the consequences for treatment exposure and survival, of thrombocytopenia induced by lomustine in recurrent glioblastoma. METHODS: We performed a retrospective analysis of the associations of thrombocytopenia with treatment delivery and outcome in EORTC 26101, a randomised trial designed to define the role of lomustine versus bevacizumab versus their combination in recurrent glioblastoma. RESULTS: A total of 225 patients were treated with lomustine alone (median 1 cycle) (group 1) and 283 patients were treated with lomustine plus bevacizumab (median 3 lomustine cycles) (group 2). Among cycle delays and dose reductions of lomustine for toxicity, thrombocytopenia was the leading cause. Among 129 patients (57%) of group 1 and 187 patients (66%) of group 2 experiencing at least one episode of thrombocytopenia, 36 patients (16%) in group 1 and 93 (33%) in group 2 had their treatment modified because of thrombocytopenia. Lomustine was discontinued for thrombocytopenia in 16 patients (7.1%) in group 1 and in 38 patients (13.4%) in group 2. On adjusted analysis accounting for major prognostic factors, dose modification induced by thrombocytopenia was associated with inferior progression-free survival in patients with MGMT promoter-methylated tumours in groups 1 and 2. This effect was noted for overall survival, too, but only for group 2 patients. CONCLUSION: Drug-induced thrombocytopenia is a major limitation to adequate exposure to lomustine chemotherapy in recurrent glioblastoma. Mitigating thrombocytopenia to enhance lomustine exposure might improve outcome in patients with MGMT promoter-methylated tumours.

[68Ga]Ga-DOTATATE-avid tumor volume, uptake and inflammation-based index correlate with survival in neuroendocrine tumor patients treated with [177Lu]Lu-DOTATATE PRRT.

To meet the increasing demand for PRRT in the treatment of patients with inoperable/disseminated well-differentiated neuroendocrine tumors (NETs) and to guide optimization strategies, adequate and accessible predictive tools that allow to stratify patients who will benefit from treatment from those who will not are becoming indispensable. Previously, we have investigated the role of baseline [68Ga]Ga-DOTATOC PET tumor uptake and volumetric parameters and a blood-derived inflammatory biomarker, the inflammation-based index (IBI), for outcome prediction in NET patients treated with [90Y]Y-DOTATOC. In this retrospective study in 83 NET patients treated with [177Lu]Lu-DOTATATE in a routine clinical setting, we aimed to evaluate the generalizability of our previous findings to [177Lu]Lu-DOTATATE treatment combined with a pre-therapeutic [68Ga]Ga-DOTATATE PET. A semi-automatic customized SUV threshold-based approach was used for tumor delineation. The previously identified SUVmean cut-off of 13.7 for better survival could not be applied to this patient cohort. Instead, a more optimal cut-off could be identified: an SUVmean lower or equal than 11.2 was associated with worse overall survival (OS) (hazard ratio (HR) 2.28; P = 0.008). Also in line with our previous study, a [68Ga]Ga-DOTATATE-avid tumor volume (TV) higher than 672 mL and an elevated baseline IBI were correlated with worse OS (HR 3.13 (P = 0.0001) and HR 2.00 (P = 0.034), respectively). Multivariate analysis confirmed independent associations between OS and baseline IBI (P = 0.032), SUVmean (P = 0.027) and [68Ga]Ga-DOTATATE-avid TV (P = 0.001). Taking baseline IBI, [68Ga]Ga-DOTATATE-avid TV and [68Ga]Ga-DOTATATE uptake into account may help guide PRRT treatment decisions.

Effectiveness of core needle biopsy in the diagnosis of thyroid lymphoma and anaplastic thyroid carcinoma: A systematic review and meta-analysis.

Background: Both anaplastic thyroid carcinoma (ATC) and thyroid lymphoma (TL) clinically present as rapidly enlarging neck masses. Unfortunately, in this situation, like in any other thyroid swelling, a routine fine-needle aspiration (FNA) cytology is the first and only diagnostic test performed at the initial contact in the average thyroid practice. FNA, however, has a low sensitivity in diagnosing ATC and TL, and by the time the often "inconclusive" result is known, precious time has evolved, before going for core-needle biopsy (CNB) or incisional biopsy (IB) as the natural next diagnostic steps. Objectives: To determine the diagnostic value of CNB in the clinical setting of a rapidly enlarging thyroid mass, via a systematic review and meta-analysis of the available data on CNB reliability in the differential diagnosis of ATC and TL. Methods: A PubMed, Embase and Web of Science database search was performed on June 23th 2021. Population of interest comprised patients who underwent CNB for clinical or ultrasonographical suspicion of ATC or TL, patients with a final diagnosis of ATC or TL after CNB, or after IB following CNB. Results: From a total of 17 studies, 166 patients were included. One hundred and thirty-six were diagnosed as TL and 14 as ATC following CNB. CNB, with a sensitivity and positive predictive value of 94,3% and 100% for TL and 80,1% and 100% for ATC respectively, proved to be superior to FNA (reported sensitivity for TL of 48% and for ATC of 61%). Furthermore, the need for additional diagnostic surgery after CNB was only 6.2% for TL and 17.6% for ATC. Conclusions: Immediately performing CNB for a suspected diagnosis of ATC and TL in a rapidly enlarging thyroid mass is more appropriate and straightforward than a stepped diagnostic pathway using FNA first and awaiting the result before doing CNB.

Early Whole-Body Diffusion-weighted MRI Helps Predict Long-term Outcome Following Peptide Receptor Radionuclide Therapy for Metastatic Neuroendocrine Tumors.

Purpose To evaluate the predictive value of 7-week apparent diffusion coefficient change from baseline (ADCratio7w) at whole-body diffusion-weighted MRI (WB-DWI MRI) after one peptide receptor radionuclide therapy (PRRT) cycle to predict outcome in patients with metastatic neuroendocrine tumor (mNET). Materials and Methods From April 2009 to May 2012, participants in a prospective clinical trial investigating yttrium 90-DOTA Phe1-Tyr3-octreotide (DOTATOC) treatment for mNET (EudraCT no. 2008-007965-22) underwent WB-DWI MRI and gallium 68 (68Ga)-DOTATOC PET/CT before and 7 weeks after one PRRT cycle. ADCratio7w response was compared with the 7-week Response Evaluation Criteria in Solid Tumors version 1.1 and 68Ga-DOTATOC PET/CT quantitative responses to predict overall survival (OS) and progression-free survival (PFS) with Cox regression analysis. Results Forty participants were analyzed (mean age, 60 years ± 11 [SD]; 21 men). Median PFS and OS were 10.5 months (range, 2-36 months) and 18 months (range, 3-81 months), respectively. Survival analysis showed significantly positive effects on PFS by age (hazard ratio [HR] = 0.96, P = .007), tumor grade (HR = 2.84, P = .006), Ki-67 index (HR = 1.05, P = .01), ADCratio7w of the least-responding lesion (ADCratio7w-least) (HR = 0.94, P < .001), and baseline mean standardized uptake values (SUVmean) (HR = 0.89, P = .02), with ADCratio7w-least and SUVmean remaining significant in multivariable analysis (P < .001, P = .02, respectively). There were significantly positive effects on OS by pretreatment lesion volume (HR = 1.004, P = .004), tumor grade (HR = 2.14, P = .04), Ki-67 index (HR = 1.05, P = .01), and ADCratio7w-least (HR = 0.97, P < .001), with pretreatment volume and ADCratio7w-least remaining significant at multivariable analysis (P = .005, P = .002, respectively). Conclusion The ADCratio7w after start of PRRT for mNET was an independent predictor of patient outcome. Keywords: MR-Diffusion-Weighted Imaging, Radionuclide Therapy, Whole-Body Imaging, Metastases, Tumor Response, Treatment Effects EudraCT no. 2008-007965-22 © RSNA, 2022.