The prognostic significance of a negative PSMA-PET scan prior to salvage radiotherapy following radical prostatectomy.

AIM: The optimal management for early recurrent prostate cancer following radical prostatectomy (RP) in patients with negative prostate-specific membrane antigen positron-emission tomography (PSMA-PET) scan is an ongoing subject of debate. The aim of this study was to evaluate the outcome of salvage radiotherapy (SRT) in patients with biochemical recurrence with negative PSMA PET finding. METHODS: This retrospective, multicenter (11 centers, 5 countries) analysis included patients who underwent SRT following biochemical recurrence (BR) of PC after RP without evidence of disease on PSMA-PET staging. Biochemical recurrence-free survival (bRFS), metastatic-free survival (MFS) and overall survival (OS) were assessed using Kaplan-Meier method. Multivariable Cox proportional hazards regression assessed predefined predictors of survival outcomes. RESULTS: Three hundred patients were included, 253 (84.3%) received SRT to the prostate bed only, 46 (15.3%) additional elective pelvic nodal irradiation, respectively. Only 41 patients (13.7%) received concomitant androgen deprivation therapy (ADT). Median follow-up after SRT was 33 months (IQR: 20-46 months). Three-year bRFS, MFS, and OS following SRT were 73.9%, 87.8%, and 99.1%, respectively. Three-year bRFS was 77.5% and 48.3% for patients with PSA levels before PSMA-PET ≤ 0.5 ng/ml and > 0.5 ng/ml, respectively. Using univariate analysis, the International Society of Urological Pathology (ISUP) grade > 2 (p = 0.006), metastatic pelvic lymph nodes at surgery (p = 0.032), seminal vesicle involvement (p < 0.001), pre-SRT PSA level of > 0.5 ng/ml (p = 0.004), and lack of concomitant ADT (p = 0.023) were significantly associated with worse bRFS. On multivariate Cox proportional hazards, seminal vesicle infiltration (p = 0.007), ISUP score >2 (p = 0.048), and pre SRT PSA level > 0.5 ng/ml (p = 0.013) remained significantly associated with worse bRFS. CONCLUSION: Favorable bRFS after SRT in patients with BR and negative PSMA-PET following RP was achieved. These data support the usage of early SRT for patients with negative PSMA-PET findings.

Whole pelvis vs. hemi pelvis elective nodal radiotherapy in patients with PSMA-positive nodal recurrence after radical prostatectomy - a retrospective multi-institutional propensity score analysis.

PURPOSE: Despite growing evidence for bilateral pelvic radiotherapy (whole pelvis RT, WPRT) there is almost no data on unilateral RT (hemi pelvis RT, HPRT) in patients with nodal recurrent prostate cancer after prostatectomy. Nevertheless, in clinical practice HPRT is sometimes used with the intention to reduce side effects compared to WPRT. Prostate-specific membrane antigen positron emission tomography / computed tomography (PSMA-PET/CT) is currently the best imaging modality in this clinical situation. This analysis compares PSMA-PET/CT based WPRT and HPRT. METHODS: A propensity score matching was performed in a multi-institutional retrospective dataset of 273 patients treated with pelvic RT due to nodal recurrence (214 WPRT, 59 HPRT). In total, 102 patients (51 in each group) were included in the final analysis. Biochemical recurrence-free survival (BRFS) defined as prostate specific antigen (PSA) < post-RT nadir + 0.2ng/ml, metastasis-free survival (MFS) and nodal recurrence-free survival (NRFS) were calculated using the Kaplan-Meier method and compared using the log rank test. RESULTS: Median follow-up was 29 months. After propensity matching, both groups were mostly well balanced. However, in the WPRT group there were still significantly more patients with additional local recurrences and biochemical persistence after prostatectomy. There were no significant differences between both groups in BRFS (p = .97), MFS (p = .43) and NRFS (p = .43). After two years, BRFS, MFS and NRFS were 61%, 86% and 88% in the WPRT group and 57%, 90% and 82% in the HPRT group, respectively. Application of a boost to lymph node metastases, a higher RT dose to the lymphatic pathways (> 50 Gy EQD2α/ß=1.5 Gy) and concomitant androgen deprivation therapy (ADT) were significantly associated with longer BRFS in uni- and multivariate analysis. CONCLUSIONS: Overall, this analysis presents the outcome of HPRT in nodal recurrent prostate cancer patients and shows that it can result in a similar oncologic outcome compared to WPRT. Nevertheless, patients in the WPRT may have been at a higher risk for progression due to some persistent imbalances between the groups. Therefore, further research should prospectively evaluate which subgroups of patients are suitable for HPRT and if HPRT leads to a clinically significant reduction in toxicity.

High-Dose Rate Brachytherapy Combined with PD-1 Blockade as a Treatment for Metastatic Adrenocortical Carcinoma - A Single Center Case Series.

The response rate of advanced adrenocortical carcinoma (ACC) to standard chemotherapy with mitotane and etoposide/doxorubicin/cisplatin (EDP-M) is unsatisfactory, and benefit is frequently short lived. Immune checkpoint inhibitors (CPI) have been examined in patient's refractory to EDP-M, but objective response rates are only approximately 15%. High-dose rate brachytherapy (HDR-BT) is a catheter-based internal radiotherapy and expected to favorably combine with immunotherapies. Here we describe three cases of patients with advanced ACC who were treated with HDR-BT and the CPI pembrolizumab. None of the tumors were positive for established response markers to CPI. All patients were female, had progressed on EDP-M and received external beam radiation therapy for metastatic ACC. Pembrolizumab was initiated 7 or 23 months after brachytherapy in two cases and prior to brachytherapy in one case. Best response of lesions treated with brachytherapy was complete (n=2) or partial response (n=1) that was ongoing at last follow up after 23, 45 and 4 months, respectively. Considering all sites of tumor, response was complete and partial remission in the two patients with brachytherapy prior to pembrolizumab. The third patient developed progressive disease with severe Cushing's syndrome and died due to COVID-19. Immune-related adverse events of colitis (grade 3), gastroduodenitis (grade 3), pneumonitis (grade 2) and thyroiditis (grade 1) occurred in the two patients with systemic response. HDR-BT controlled metastases locally. Sequential combination with CPI therapy may enhance an abscopal antitumoral effect in non-irradiated metastases in ACC. Systematic studies are required to confirm this preliminary experience and to understand underlying mechanisms.

Assessment of intrafractional prostate motion and its dosimetric impact in MRI-guided online adaptive radiotherapy with gating.

PURPOSE: This study aimed to evaluate the intrafractional prostate motion captured during gated magnetic resonance imaging (MRI)-guided online adaptive radiotherapy for prostate cancer and analyze its impact on the delivered dose as well as the effect of gating. METHODS: Sagittal 2D cine-MRI scans were acquired at 4 Hz during treatment at a ViewRay MRIdian (ViewRay Inc., Oakwood Village, OH, USA) MR linac. Prostate shifts in anterior-posterior (AP) and superior-inferior (SI) directions were extracted separately. Using the static dose cloud approximation, the planned fractional dose was shifted according to the 2D gated motion (residual motion in gating window) to estimate the delivered dose by superimposing and averaging the shifted dose volumes. The dose of a hypothetical non-gated delivery was reconstructed similarly using the non-gated motion. For the clinical target volume (CTV), rectum, and bladder, dose-volume histogram parameters of the planned and reconstructed doses were compared. RESULTS: In total, 174 fractions (15.7 h of cine-MRI) from 10 patients were evaluated. The average (±1 σ) non-gated prostate motion was 0.6 ± 1.0 mm in the AP and 0.0 ± 0.6 mm in the SI direction with respect to the centroid position of the gating boundary. 95% of the shifts were within [-3.5, 2.7] mm in the AP and [-2.9, 3.2] mm in the SI direction. For the gated treatment and averaged over all fractions, CTV D98% decreased by less than 2% for all patients. The rectum and the bladder D2% increased by less than 3% and 0.5%, respectively. Doses reconstructed for gated and non-gated delivery were similar for most fractions. CONCLUSION: A pipeline for extraction of prostate motion during gated MRI-guided radiotherapy based on 2D cine-MRI was implemented. The 2D motion data enabled an approximate estimation of the delivered dose. For the majority of fractions, the benefit of gating was negligible, and clinical dosimetric constraints were met, indicating safety of the currently adopted gated MRI-guided treatment workflow.

First-site-metastasis pattern in patients with inoperable stage III NSCLC treated with concurrent chemoradiotherapy with or without immune check-point inhibition: a retrospective analysis.

PURPOSE: The aim of this study was to investigate a first-site-metastasis pattern (FSMP) in unresectable stage III NSCLC after concurrent chemoradiotherapy (cCRT) with or without immune checkpoint inhibition (ICI). METHODS: We defined three patient subgroups according to the year of initial multimodal treatment: A (2011-2014), B (2015-2017) and C (2018-2020). Different treatment-related parameters were analyzed. Observed outcome parameters were brain metastasis-free survival (BMFS), extracranial distant metastasis-free survival (ecDMFS) and distant metastasis-free survival (DMFS). RESULTS: 136 patients treated between 2011 and 2020 were included with ≥ 60.0 Gy total dose and concurrent chemotherapy (cCRT); thirty-six (26%) received ICI. Median follow-up was 49.7 (range:0.7-126.1), median OS 31.2 (95% CI:16.4-30.3) months (23.4 for non-ICI vs not reached for ICI patients, p = 0.001). Median BMFS/ecDMFS/DMFS in subgroups A, B and C was 14.9/16.3/14.7 months, 20.6/12.9/12.7 months and not reached (NR)/NR/36.4 months (p = 0.004/0.001/0.016). For cCRT+ICI median BMFS was 53.1 vs. 19.1 months for cCRT alone (p = 0.005). Median ecDMFS achieved 55.2 vs. 17.9 (p = 0.003) and median DMFS 29.5 (95% CI: 1.4-57.6) vs 14.93 (95% CI:10.8-19.0) months (p = 0.031), respectively. Multivariate analysis showed that age over 65 (HR:1.629; p = 0.036), GTV ≥ 78 cc (HR: 2.100; p = 0.002) and V20 ≥ 30 (HR: 2.400; p = 0.002) were negative prognosticators for BMFS and GTV ≥ 78 cc for ecDMFS (HR: 1.739; p = 0.027). After onset of brain metastasis (BM), patients survived 13.3 (95% CI: 6.4-20.2) months and 8.6 months (95% CI: 1.6-15.5) after extracranial-distant-metastasis (ecDM). Patients with ecDM as FSMP reached significantly worse overall survival of 22.1 (range:14.4-29.8) vs. 40.1 (range:18.7-61.3) months (p = 0.034) in the rest of cohort. In contrast, BM as FSMP had no impact on OS. CONCLUSION: This retrospective analysis of inoperable stage III NSCLC patients revealed that age over 65, V20 ≥ 30 and GTV ≥ 78 cc were prognosticators for BMFS and GTV ≥ 78 cc for ecDMFS. ICI treatment led to a significant improvement of BMFS, ecDMFS and DMFS. ecDM as FSMP was associated with significant deterioration of OS, whereas BM as FSMP was not.

Metabolic patterns on [18F]FDG PET/CT in patients with unresectable stage III NSCLC undergoing chemoradiotherapy ± durvalumab maintenance treatment.

PURPOSE: In patients with unresectable stage III non-small-cell lung cancer (NSCLC), durvalumab maintenance treatment after chemoradiotherapy (CRT) significantly improves survival. So far, however, metabolic changes of tumoral lesions and secondary lymphoid organs under durvalumab are unknown. Hence, we assessed changes on [18F]FDG PET/CT in comparison to patients undergoing CRT alone. METHODS: Forty-three patients with [18F]FDG PET/CT both before and after standard CRT for unresectable stage III NSCLC were included, in 16/43 patients durvalumab maintenance treatment was initiated (CRT-IO) prior to the second PET/CT. Uptake of tumor sites and secondary lymphoid organs was compared between CRT and CRT-IO. Also, readers were blinded for durvalumab administration and reviewed scans for findings suspicious for immunotherapy-related adverse events (irAE). RESULTS: Initial uptake characteristics were comparable. However, under durvalumab, diverging metabolic patterns were noted: There was a significantly higher reduction of tumoral uptake intensity in CRT-IO compared to CRT, e.g. median decrease of SUVmax -70.0% vs. -24.8%, p = 0.009. In contrast, the spleen uptake increased in CRT-IO while it dropped in CRT (median + 12.5% vs. -4.4%, p = 0.029). Overall survival was significantly longer in CRT-IO compared to CRT with few events (progression/death) noted in CRT-IO. Findings suggestive of irAE were present on PET/CT more often in CRT-IO (12/16) compared to CRT (8/27 patients), p = 0.005. CONCLUSION: Durvalumab maintenance treatment after CRT leads to diverging tumoral metabolic changes, but also increases splenic metabolism and leads to a higher proportion of findings suggestive of irAE compared to patients without durvalumab. Due to significantly prolonged survival with durvalumab, survival analysis will be substantiated in correlation to metabolic changes as soon as more clinical events are present.

A convolutional neural network with self-attention for fully automated metabolic tumor volume delineation of head and neck cancer in [Formula: see text]F]FDG PET/CT.

PURPOSE: PET-derived metabolic tumor volume (MTV) and total lesion glycolysis of the primary tumor are known to be prognostic of clinical outcome in head and neck cancer (HNC). Including evaluation of lymph node metastases can further increase the prognostic value of PET but accurate manual delineation and classification of all lesions is time-consuming and prone to interobserver variability. Our goal, therefore, was development and evaluation of an automated tool for MTV delineation/classification of primary tumor and lymph node metastases in PET/CT investigations of HNC patients. METHODS: Automated lesion delineation was performed with a residual 3D U-Net convolutional neural network (CNN) incorporating a multi-head self-attention block. 698 [Formula: see text]F]FDG PET/CT scans from 3 different sites and 5 public databases were used for network training and testing. An external dataset of 181 [Formula: see text]F]FDG PET/CT scans from 2 additional sites was employed to assess the generalizability of the network. In these data, primary tumor and lymph node (LN) metastases were interactively delineated and labeled by two experienced physicians. Performance of the trained network models was assessed by 5-fold cross-validation in the main dataset and by pooling results from the 5 developed models in the external dataset. The Dice similarity coefficient (DSC) for individual delineation tasks and the primary tumor/metastasis classification accuracy were used as evaluation metrics. Additionally, a survival analysis using univariate Cox regression was performed comparing achieved group separation for manual and automated delineation, respectively. RESULTS: In the cross-validation experiment, delineation of all malignant lesions with the trained U-Net models achieves DSC of 0.885, 0.805, and 0.870 for primary tumor, LN metastases, and the union of both, respectively. In external testing, the DSC reaches 0.850, 0.724, and 0.823 for primary tumor, LN metastases, and the union of both, respectively. The voxel classification accuracy was 98.0% and 97.9% in cross-validation and external data, respectively. Univariate Cox analysis in the cross-validation and the external testing reveals that manually and automatically derived total MTVs are both highly prognostic with respect to overall survival, yielding essentially identical hazard ratios (HR) ([Formula: see text]; [Formula: see text] vs. [Formula: see text]; [Formula: see text] in cross-validation and [Formula: see text]; [Formula: see text] vs. [Formula: see text]; [Formula: see text] in external testing). CONCLUSION: To the best of our knowledge, this work presents the first CNN model for successful MTV delineation and lesion classification in HNC. In the vast majority of patients, the network performs satisfactory delineation and classification of primary tumor and lymph node metastases and only rarely requires more than minimal manual correction. It is thus able to massively facilitate study data evaluation in large patient groups and also does have clear potential for supervised clinical application.

Next-generation PET/CT imaging in meningioma-first clinical experiences using the novel SSTR-targeting peptide [18F]SiTATE.

BACKGROUND: Somatostatin-receptor (SSTR)-targeted PET/CT provides important clinical information in addition to standard imaging in meningioma patients. [18F]SiTATE is a novel, 18F-labeled SSTR-targeting peptide with superior imaging properties according to preliminary data. We provide the first [18F]SiTATE PET/CT data of a large cohort of meningioma patients. METHODS: Patients with known or suspected meningioma undergoing [18F]SiTATE PET/CT were included. Uptake intensity (SUV) of meningiomas, non-meningioma lesions, and healthy organs were assessed using a 50% isocontour volume of interest (VOI) or a spherical VOI, respectively. Also, trans-osseous extension on PET/CT was assessed. RESULTS: A total of 107 patients with 117 [18F]SiTATE PET/CT scans were included. Overall, 231 meningioma lesions and 61 non-meningioma lesions (e.g., post-therapeutic changes) were analyzed. Physiological uptake was lowest in healthy brain tissue, followed by bone marrow, parotid, and pituitary (SUVmean 0.06 ± 0.04 vs. 1.4 ± 0.9 vs. 1.6 ± 1.0 vs. 9.8 ± 4.6; p < 0.001). Meningiomas showed significantly higher uptake than non-meningioma lesions (SUVmax 11.6 ± 10.6 vs. 4.0 ± 3.3, p < 0.001). Meningiomas showed significantly higher uptake than non-meningioma lesions (SUVmax 11.6±10.6 vs. 4.0±3.3, p<0.001). 93/231 (40.3%) meningiomas showed partial trans-osseous extension and 34/231 (14.7%) predominant intra-osseous extension. 59/231 (25.6%) meningioma lesions found on PET/CT had not been reported on previous standard imaging. CONCLUSION: This is the first PET/CT study using an 18F-labeled SSTR-ligand in meningioma patients: [18F]SiTATE provides extraordinary contrast in meningioma compared to healthy tissue and non-meningioma lesions, which leads to a high detection rate of so far unknown meningioma sites and osseous involvement. Having in mind the advantageous logistic features of 18F-labeled compared to 68Ga-labeled compounds (e.g., longer half-life and large-badge production), [18F]SiTATE has the potential to foster a widespread use of SSTR-targeted imaging in neuro-oncology.

PSMA-PET/CT-guided salvage radiotherapy in recurrent or persistent prostate cancer and PSA < 0.2 ng/ml.

PURPOSE: The purpose of this retrospective, multicenter study was to assess efficacy of PSMA-PET/CT-guided salvage radiotherapy (sRT) in patients with recurrent or persistent PSA after primary surgery and PSA levels < 0.2 ng/ml. METHODS: The study included patients from a pooled cohort (n = 1223) of 11 centers from 6 countries. Patients with PSA levels > 0.2 ng/ml prior to sRT or without sRT to the prostatic fossa were excluded. The primary study endpoint was biochemical recurrence-free survival (BRFS) and BR was defined as PSA nadir after sRT + 0.2 ng/ml. Cox regression analysis was performed to assess the impact of clinical parameters on BRFS. Recurrence patterns after sRT were analyzed. RESULTS: The final cohort consisted of 273 patients; 78/273 (28.6%) and 48/273 (17.6%) patients had local or nodal recurrence on PET/CT. The most frequently applied sRT dose to the prostatic fossa was 66-70 Gy (n = 143/273, 52.4%). SRT to pelvic lymphatics was delivered in 87/273 (31.9%) patients and androgen deprivation therapy was given to 36/273 (13.2%) patients. After a median follow-up time of 31.1 months (IQR: 20-44), 60/273 (22%) patients had biochemical recurrence. The 2- and 3-year BRFS was 90.1% and 79.2%, respectively. The presence of seminal vesicle invasion in surgery (p = 0.019) and local recurrences in PET/CT (p = 0.039) had a significant impact on BR in multivariate analysis. In 16 patients, information on recurrence patterns on PSMA-PET/CT after sRT was available and one had recurrent disease inside the RT field. CONCLUSION: This multicenter analysis suggests that implementation of PSMA-PET/CT imaging for sRT guidance might be of benefit for patients with very low PSA levels after surgery due to promising BRFS rates and a low number of relapses within the sRT field.

Development of PSMA-PET-guided CT-based radiomic signature to predict biochemical recurrence after salvage radiotherapy.

PURPOSE: To develop a CT-based radiomic signature to predict biochemical recurrence (BCR) in prostate cancer patients after sRT guided by positron-emission tomography targeting prostate-specific membrane antigen (PSMA-PET). MATERIAL AND METHODS: Consecutive patients, who underwent 68Ga-PSMA11-PET/CT-guided sRT from three high-volume centers in Germany, were included in this retrospective multicenter study. Patients had PET-positive local recurrences and were treated with intensity-modulated sRT. Radiomic features were extracted from volumes of interests on CT guided by focal PSMA-PET uptakes. After preprocessing, clinical, radiomics, and combined clinical-radiomic models were developed combining different feature reduction techniques and Cox proportional hazard models within a nested cross validation approach. RESULTS: Among 99 patients, median interval until BCR was the radiomic models outperformed clinical models and combined clinical-radiomic models for prediction of BCR with a C-index of 0.71 compared to 0.53 and 0.63 in the test sets, respectively. In contrast to the other models, the radiomic model achieved significantly improved patient stratification in Kaplan-Meier analysis. The radiomic and clinical-radiomic model achieved a significantly better time-dependent net reclassification improvement index (0.392 and 0.762, respectively) compared to the clinical model. Decision curve analysis demonstrated a clinical net benefit for both models. Mean intensity was the most predictive radiomic feature. CONCLUSION: This is the first study to develop a PSMA-PET-guided CT-based radiomic model to predict BCR after sRT. The radiomic models outperformed clinical models and might contribute to guide personalized treatment decisions.

European Society for Radiotherapy and Oncology Advisory Committee in Radiation Oncology Practice consensus recommendations on patient selection and dose and fractionation for external beam radiotherapy in early breast cancer.

High-quality randomised clinical trials testing moderately fractionated breast radiotherapy have clearly shown that local control and survival is at least as effective as with 2 Gy daily fractions with similar or reduced normal tissue toxicity. Fewer treatment visits are welcomed by patients and their families, and reduced fractions produce substantial savings for health-care systems. Implementation of hypofractionation, however, has moved at a slow pace. The oncology community have now reached an inflection point created by new evidence from the FAST-Forward five-fraction randomised trial and catalysed by the need for the global radiation oncology community to unite during the COVID-19 pandemic and rapidly rethink hypofractionation implementation. The aim of this paper is to support equity of access for all patients to receive evidence-based breast external beam radiotherapy and to facilitate the translation of new evidence into routine daily practice. The results from this European Society for Radiotherapy and Oncology Advisory Committee in Radiation Oncology Practice consensus state that moderately hypofractionated radiotherapy can be offered to any patient for whole breast, chest wall (with or without reconstruction), and nodal volumes. Ultrafractionation (five fractions) can also be offered for non-nodal breast or chest wall (without reconstruction) radiotherapy either as standard of care or within a randomised trial or prospective cohort. The consensus is timely; not only is it a pragmatic framework for radiation oncologists, but it provides a measured proposal for the path forward to influence policy makers and empower patients to ensure equity of access to evidence-based radiotherapy.

Simultaneous metabolite MALDI-MSI, whole exome and transcriptome analysis from formalin-fixed paraffin-embedded tissue sections.

Matrix-assisted laser desorption ionization mass spectrometry imaging (MALDI-MSI) allows spatial analysis of proteins, metabolites, or small molecules from tissue sections. Here, we present the simultaneous generation and analysis of MALDI-MSI, whole-exome sequencing (WES), and RNA-sequencing data from the same formalin-fixed paraffin-embedded (FFPE) tissue sections. Genomic DNA and total RNA were extracted from (i) untreated, (ii) hematoxylin-eosin (HE) stained, and (iii) MALDI-MSI-analyzed FFPE tissue sections from three head and neck squamous cell carcinomas. MALDI-MSI data were generated by a time-of-flight analyzer prior to preprocessing and visualization. WES data were generated using a low-input protocol followed by detection of single-nucleotide variants (SNVs), tumor mutational burden, and mutational signatures. The transcriptome was determined using 3'-RNA sequencing and was examined for similarities and differences between processing stages. All data met the commonly accepted quality criteria. Besides SNVs commonly identified between differently processed tissues, FFPE-typical artifactual variants were detected. Tumor mutational burden was in the same range for tissues from the same patient and mutational signatures were highly overlapping. Transcriptome profiles showed high levels of correlation. Our data demonstrate that simultaneous molecular profiling of MALDI-MSI-processed FFPE tissue sections at the transcriptome and exome levels is feasible and reliable.

A transcriptomic map of EGFR-induced epithelial-to-mesenchymal transition identifies prognostic and therapeutic targets for head and neck cancer.

BACKGROUND: Epidermal growth factor receptor (EGFR) is both a driver oncogene and a therapeutic target in advanced head and neck squamous cell carcinoma (HNSCC). However, response to EGFR treatment is inconsistent and lacks markers for treatment prediction. This study investigated EGFR-induced epithelial-to-mesenchymal transition (EMT) as a central parameter in tumor progression and identified novel prognostic and therapeutic targets, and a candidate predictive marker for EGFR therapy response. METHODS: Transcriptomic profiles were analyzed by RNA sequencing (RNA-seq) following EGFR-mediated EMT in responsive human HNSCC cell lines. Exclusive genes were extracted via differentially expressed genes (DEGs) and a risk score was determined through forward feature selection and Cox regression models in HNSCC cohorts. Functional characterization of selected prognostic genes was conducted in 2D and 3D cellular models, and findings were validated by immunohistochemistry in primary HNSCC. RESULTS: An EGFR-mediated EMT gene signature composed of n = 171 genes was identified in responsive cell lines and transferred to the TCGA-HNSCC cohort. A 5-gene risk score comprising DDIT4, FADD, ITGB4, NCEH1, and TIMP1 prognosticated overall survival (OS) in TCGA and was confirmed in independent HNSCC cohorts. The EGFR-mediated EMT signature was distinct from EMT hallmark and partial EMT (pEMT) meta-programs with a differing enrichment pattern in single malignant cells. Molecular characterization showed that ITGB4 was upregulated in primary tumors and metastases compared to normal mucosa and correlated with EGFR/MAPK activity in tumor bulk and single malignant cells. Preferential localization of ITGB4 together with its ligand laminin 5 at tumor-stroma interfaces correlated with increased tumor budding in primary HNSCC tissue sections. In vitro, ITGB4 knock-down reduced EGFR-mediated migration and invasion and ITGB4-antagonizing antibody ASC8 impaired 2D and 3D invasion. Furthermore, a logistic regression model defined ITGB4 as a predictive marker of progression-free survival in response to Cetuximab in recurrent metastatic HNSCC patients. CONCLUSIONS: EGFR-mediated EMT conveyed through MAPK activation contributes to HNSCC progression upon induction of migration and invasion. A 5-gene risk score based on a novel EGFR-mediated EMT signature prognosticated survival of HNSCC patients and determined ITGB4 as potential therapeutic and predictive target in patients with strong EGFR-mediated EMT.

Tumor DNA-methylome derived epigenetic fingerprint identifies HPV-negative head and neck patients at risk for locoregional recurrence after postoperative radiochemotherapy.

Biomarkers with relevance for loco-regional therapy are needed in human papillomavirus negative aka HPV(-) head and neck squamous cell carcinoma (HNSCC). Based on the premise that DNA methylation pattern is highly conserved, we sought to develop a reliable and robust methylome-based classifier identifying HPV(-) HNSCC patients at risk for loco-regional recurrence (LR) and all-event progression after postoperative radiochemotherapy (PORT-C). The training cohort consisted of HPV-DNA negative HNSCC patients (n = 128) homogeneously treated with PORT-C in frame of the German Cancer Consortium-Radiation Oncology Group (DKTK-ROG) multicenter biomarker trial. DNA Methylation analysis was performed using Illumina 450 K and 850 K-EPIC microarray technology. The performance of the classifier was integrated with a series of biomarkers studied in the training set namely hypoxia-, 5-microRNA (5-miR), stem-cell gene-expression signatures and immunohistochemistry (IHC)-based immunological characterization of tumors (CD3/CD8/PD-L1/PD1). Validation occurred in an independent cohort of HPV(-) HNSCC patients, pooled from two German centers (n = 125). We identified a 38-methylation probe-based HPV(-) Independent Classifier of disease Recurrence (HICR) with high prognostic value for LR, distant metastasis and overall survival (P < 10-9 ). HICR remained significant after multivariate analysis adjusting for anatomical site, lymph node extracapsular extension (ECE) and size (T-stage). HICR high-risk tumors were enriched for younger patients with hypoxic tumors (15-gene signature) and elevated 5-miR score. After adjustment for hypoxia and 5-miR covariates, HICR maintained predicting all endpoints. HICR provides a novel mean for assessing the risk of LR in HPV(-) HNSCC patients treated with PORT-C and opens a new opportunity for biomarker-assisted stratification and therapy adaptation in these patients.

Pooled analysis on image-guided moderately hypofractionated thoracic irradiation in inoperable node-positive/recurrent patients with non-small cell lung cancer with poor prognostic factors and severely limited pulmonary function and reserve.

BACKGROUND: The objective of this study was to investigate the feasibility and efficacy of image-guided moderately hypofractionated thoracic radiotherapy (hypo-IGRT) in patients with non-small cell lung cancer (NSCLC) with poor performance status and severely limited pulmonary function and reserve. METHODS: Consecutive inoperable patients who had node-positive, stage IIB-IIIC (TNM, 8th edition) or recurrent NSCLC, had an Eastern Cooperative Oncology Group performance status ≥1, and had a forced expiratory volume in 1 second (FEV1 ) ≤1.0 L, had a single-breath diffusing capacity of the lung for carbon monoxide (DLCO-SB) ≤40% and/or on long-term oxygen therapy were analyzed. All patients received hypofractionated IGRT to a total dose of 42.0 to 49.0 Gy/13 to 16 fractions (2.8-3.5 Gy/fraction) (equivalent dose in 2-Gy fractions/biologically effective dose [α/ß = 10] = 45.5-55.1 Gy/54.6-66.2 Gy) alone. Patients were monitored closely for nonhematological toxicity, which was classified per National Cancer Institute Common Terminology Criteria for Adverse Events version 5.0. RESULTS: Between 2014 and 2021, 47 consecutive patients with a median age of 72 years (range, 52.2-88 years) were treated. At baseline, the median FEV1 , vital capacity, and DLCO-SB were 1.17 L (range, 0.69-2.84 L), 2.34 L (range, 1.23-3.74 L), and 35% predicted (range, 13.3%-69.0%), respectively. The mean and median planning target volumes were 410.8 cc (SD, 267.1 cc) and 315.4 cc (range, 83.4-1174.1 cc). With a median follow-up of 28.9 months (range, 0.5-90.6 months) after RT, the median progression-free survival (PFS)/overall survival (OS) and 6- and 12-month PFS/OS rates were 10.4 months (95% CI, 7-13.8 months)/18.3 months (95% CI, 9.2-27.4 months), 70%/89.4%, and 38.8%/66%, respectively. Treatment was well tolerated with only 1 case each of grade 3 pneumonitis and esophagitis. No toxicity greater than grade 3 was observed. CONCLUSIONS: Patients with inoperable node-positive NSCLC, a poor performance status, and severely limited lung function can be safely and effectively treated with individualized moderately hypofractionated IGRT. The achieved survival rates for this highly multimorbid group of patients were encouraging.

Tumor-Specific Delivery of 5-Fluorouracil-Incorporated Epidermal Growth Factor Receptor-Targeted Aptamers as an Efficient Treatment in Pancreatic Ductal Adenocarcinoma Models.

BACKGROUNDS & AIMS: Fluoropyrimidine c (5-fluorouracil [5FU]) increasingly represents the chemotherapeutic backbone for neoadjuvant, adjuvant, and palliative treatment of pancreatic ductal adenocarcinoma (PDAC). Even in combination with other agents, 5FU efficacy remains transient and limited. One explanation for the inadequate response is insufficient and nonspecific delivery of 5FU to the tumor. METHODS: We designed, generated, and characterized 5FU-incorporated systematic evolution of ligands by exponential enrichment (SELEX)-selected epidermal growth factor receptor (EGFR)-targeted aptamers for tumor-specific delivery of 5FU to PDAC cells and tested their therapeutic efficacy in vitro and in vivo. RESULTS: 5FU-EGFR aptamers reduced proliferation in a concentration-dependent manner in mouse and human pancreatic cancer cell lines. Time-lapsed live imaging showed EGFR-specific uptake of aptamers via clathrin-dependent endocytosis. The 5FU-aptamer treatment was equally effective in 5FU-sensitive and 5FU-refractory PDAC cell lines. Biweekly treatment with 5FU-EGFR aptamers reduced tumor burden in a syngeneic orthotopic transplantation model of PDAC, in an autochthonously growing genetically engineered PDAC model (LSL-KrasG12D/+;LSL-Trp53flox/+;Ptf1a-Cre [KPC]), in an orthotopic cell line-derived xenograft model using human PDAC cells in athymic mice (CDX; Crl:NU-Foxn1nu), and in patient-derived organoids. Tumor growth was significantly attenuated during 5FU-EGFR aptamer treatment in the course of follow-up. CONCLUSIONS: Tumor-specific targeted delivery of 5FU using EGFR aptamers as the carrier achieved high target specificity; overcame 5FU resistance; and proved to be effective in a syngeneic orthotopic transplantation model, in KPC mice, in a CDX model, and in patient-derived organoids and, therefore, represents a promising backbone for pancreatic cancer chemotherapy in patients. Furthermore, our approach has the potential to target virtually any cancer entity sensitive to 5FU treatment by incorporating 5FU into cancer cell-targeting aptamers as the delivery platform.

Planning target volume as a predictor of disease progression in inoperable stage III non-small cell lung cancer patients treated with chemoradiotherapy and concurrent and/or sequential immune checkpoint inhibition.

BACKGROUND: The present study evaluates outcome after chemoradiotherapy (CRT) with concurrent and/or sequential Programmed Cell Death 1 (PD-1) or Ligand 1 (PD-L1) immune checkpoint inhibition (CPI) for inoperable stage III NSCLC patients depending on planning target volume (PTV). METHOD AND PATIENTS: Prospective data of thirty-three consecutive patients with inoperable stage III NSCLC treated with CRT and sequential durvalumab (67%, 22 patients) or concurrent and sequential nivolumab (33%, 11 patients) were analyzed. Different PTV cut offs and PTV as a continuous variable were evaluated for their association with progression-free (PFS), local-regional progression-free (LRPFS), extracranial distant metastasis-free (eMFS) and brain-metastasis free-survival (BMFS). RESULTS: All patients were treated with conventionally fractionated thoracic radiotherapy (TRT); 93% to a total dose of at least 60 Gy, 97% of patients received two cycles of concurrent platinum-based chemotherapy. Median follow-up for the entire cohort was 19.9 (range: 6.0-42.4) months; median overall survival (OS), LRFS, BMFS and eMFS were not reached. Median PFS was 22.8 (95% CI: 10.7-34.8) months. Patients with PTV ≥ 900ccm had a significantly shorter PFS (6.9 vs 22.8 months, p = 0.020) and eMFS (8.1 months vs. not reached, p = 0.003). Furthermore, patients with PTV ≥ 900ccm and stage IIIC disease (UICC-TNM Classification 8th Edition) achieved a very poor outcome with a median PFS and eMFS of 3.6 vs 22.8 months (p < 0.001) and 3.6 months vs. not reached (p = 0.001), respectively. PTV as a continuous variable also had a significant impact on eMFS (p = 0.048). However, no significant association of different PTV cut-offs or PTV as a continuous variable with LRPFS and BMFS could be shown. The multivariate analysis that was performed for PTV ≥ 900ccm and age (≥ 65 years), gender (male), histology (non-ACC) as well as T- and N-stage (T4, N3) as covariates also revealed PTV ≥ 900ccm as the only factor that had a significant correlation with PFS (HR: 5.383 (95% CI:1.263-22.942, p = 0.023)). CONCLUSION: In this prospective analysis of inoperable stage III NSCLC patients treated with definitive CRT combined with concurrent and/or sequential CPI, significantly shorter PFS and eMFS were observed in patients with initial PTV ≥ 900ccm.

Radiotherapy in oligometastatic prostate cancer-a pattern of care survey among members of the German Society for Radiation Oncology (DEGRO).

PURPOSE: Due to improved imaging, oligometastatic prostate cancer (OMPC) is diagnosed more frequently. Growing evidence shows that patients with a limited number of metastases benefit from primary-directed radiotherapy (PDT) as well as from metastasis-directed radiotherapy (MDT). This survey investigates the current treatment practice for OMPC among German-speaking radiation oncologists. METHODS: Members of the German Society for Radiation Oncology (Deutsche Gesellschaft für Radioonkologie [DEGRO]) were surveyed regarding their current treatment practice via an anonymous online questionnaire sent by email. The survey included six general items and 14 specific items regarding treatment characteristics. Questionnaires with at least 50% of questions completed were considered for further analysis. RESULTS: A total of 204 responses were received (15% response rate), 167 were considered for further analysis. Most respondents stated to be specialized in treating prostate cancer patients and to treat 10-30 patients with OMPC per annum; 97% considered PSMA-PET/CT necessary to define oligometastatic disease. Opinions differed regarding the use of systemic therapies: 63% of the respondents aimed to defer systemic therapy using radiotherapy in OMPC, whereas 37% considered systemic therapy necessary. In the setting of synchronous OMPC, 97% recommended PDT with or without a combination of MDT and/or systemic therapy. For metachronous nodal or bone oligometastatic recurrence, 98 and 99%, respectively, would opt for MDT. The majority would combine MDT with systemic therapy in patients with metachronous oligorecurrence. Respondents recommended normofractionation, hypofractionation, and SBRT for lymph node metastases in 49, 27, and 24%, respectively. No consensus existed regarding the field size for MDT of lymph node metastases. Most respondents preferred > 5 fractions for treatment of bone metastases. CONCLUSION: Local radiotherapy for PDT and MDT is routinely used among respondents of this survey, representing 12% of all German-speaking radiation oncologists. The timing of systemic therapy, fractionation schedules, and field sizes are handled differently and remain an area of active investigation.

Outcome after PSMA-PET/CT-based salvage radiotherapy for nodal recurrence after radical prostatectomy.

PURPOSE: Nodal recurrent prostate cancer (PCa) represents a common state of disease, amenable to local therapy. PSMA-PET/CT detects PCa recurrence at low PSA levels. The aim of this study was to evaluate the outcome of PSMA-PET/CT-based salvage radiotherapy (sRT) for lymph node (LN) recurrence. METHODS: A total of 100 consecutive patients treated with PSMA-PET/CT-based salvage elective nodal radiotherapy (sENRT) for LN recurrence were retrospectively examined. Patients underwent PSMA-PET/CT scan due to biochemical persistence (bcP, 76%) or biochemical recurrence (bcR, 24%) after radical prostatectomy (RP). Biochemical recurrence-free survival (BRFS) defined as PSA < post-RT nadir + 0.2 ng/ml and distant metastasis-free survival (DMFS) were calculated using the Kaplan-Meier method and uni- and multivariate analysis was performed. RESULTS: Median follow-up was 37 months. Median PSA at PSMA-PET/CT was 1.7 ng/ml (range 0.1-40.1) in patients with bcP and 1.4 ng/ml (range 0.3-5.1) in patients with bcR. PSMA-PET/CT detected 1, 2, and 3 or more LN metastases in 35%, 23%, and 42%, respectively. Eighty-three percent had only pelvic, 2% had only paraaortic, and 15% had pelvic and paraaortic LN metastases. Cumulatively, a total dose converted to EQD21.5 Gy of 66 Gy (60-70 Gy) was delivered to the prostatic fossa, 70 Gy (66-72 Gy) to the local recurrence, if present, 65.1 Gy (56-66 Gy) to PET-positive lymph nodes, and 47.5 Gy (42.4-50.9 Gy) to the lymphatic pathways. Concomitant androgen deprivation therapy (ADT) was administered in 83% of patients. One-, 2-, and 3-year BRFS was 80.7%, 71.6%, and 65.8%, respectively. One-, 2-, and 3-year DMFS was 91.6%, 79.1%, and 66.4%, respectively. In multivariate analysis, concomitant ADT, longer ADT duration (≥ 12 vs. < 12 months) and LN localization (pelvic vs. paraaortic) were associated with improved BRFS and concomitant ADT and lower PSA value before sRT (< 1 vs. > 1 ng/ml) with improved DMFS, respectively. No such association was seen for the number of affected lymph nodes. CONCLUSIONS: Overall, the present analysis shows that the so far, unmatched sensitivity and specificity of PSMA-PET/CT translates in comparably high BRFS and DMFS after PSMA-PET/CT-based sENRT for patients with PCa LN recurrence. Concomitant ADT, duration of ADT, PSA value before sRT, and localization of LN metastases were significant factors for improved outcome.

Differential role of residual metabolic tumor volume in inoperable stage III NSCLC after chemoradiotherapy ± immune checkpoint inhibition.

BACKGROUND: The PET-derived metabolic tumor volume (MTV) is an independent prognosticator in non-small cell lung cancer (NSCLC) patients. We analyzed the prognostic value of residual MTV (rMTV) after completion of chemoradiotherapy (CRT) in inoperable stage III NSCLC patients with and without immune checkpoint inhibition (ICI). METHODS: Fifty-six inoperable stage III NSCLC patients (16 female, median 65.0 years) underwent 18F-FDG PET/CT after completion of standard CRT. rMTV was delineated on 18F-FDG PET/CT using a standard threshold (liver SUVmean + 2 × standard deviation). 21/56 patients underwent additional ICI (CRT-IO, 21/56 patients) thereafter. Patients were divided in volumetric subgroups using median split dichotomization (MTV ≤ 4.3 ml vs. > 4.3 ml). rMTV, clinical features, and ICI-application were correlated with clinical outcome parameters (progression-free survival (PFS), local PFS (LPFS), and overall survival (OS). RESULTS: Overall, median follow-up was 52.0 months. Smaller rMTV was associated with longer median PFS (29.3 vs. 10.5 months, p = 0.015), LPFS (49.9 vs. 13.5 months, p = 0.001), and OS (63.0 vs. 23.0 months, p = 0.003). CRT-IO patients compared to CRT patients showed significantly longer median PFS (29.3 vs. 11.2 months, p = 0.034), LPFS (median not reached vs. 14.0 months, p = 0.016), and OS (median not reached vs. 25.2 months, p = 0.007). In the CRT subgroup, smaller rMTV was associated with longer median PFS (33.5 vs. 8.6 months, p = 0.001), LPFS (49.9 vs. 10.1 months, p = 0.001), and OS (63.0 vs. 16.3 months, p = 0.004). In the CRT-IO subgroup, neither PFS, LPFS, nor OS were associated with MTV (p > 0.05 each). The findings were confirmed in subsequent multivariate analyses. CONCLUSION: In stage III NSCLC, smaller rMTV is highly associated with superior clinical outcome, especially in patients undergoing CRT without ICI. Patients with CRT-IO show significantly improved outcome compared to CRT patients. Of note, clinical outcome in CRT-IO patients is independent of residual MTV. Hence, even patients with large rMTV might profit from ICI despite extensive tumor load.