Background Predicting the occurrence and/or severity of oral mucositis (OM) before commencing radiotherapy (RT) remains very difficult. The aim of this prospective trial was to investigate whether the ex-vivo radiation sensitivity of oral keratinocytes from head and neck (H&N) cancer patients correlates with severe OM. Methods Oral microbiopsies of healthy gingival mucosa were collected from 63H&N cancer patients undergoing (chemo)RT, of which 58 samples were useable. Keratinocytes from these microbiopsies underwent ex-vivo proliferation, irradiation, and subsequently the cell spreading assay. Tubes with the cell suspension were placed within the irradiation chamber of a 137Cs Gammacell 40 Exactor (Best Theratronics, Canada) and exposed to 0, 2, 4, 6, or 8 Gy at a dose rate of 0.63 Gy min−1. Cell suspension was then immediately pipetted into custom-made polydimethylsiloxane (PDMS) rings.The effect of demographic and clinical parameters on the cell spreading assay were also analyzed. Systematic clinical recording of OM was conducted twice a week by a specially trained examiner. Results Most patients had node-positive disease and cancer of the oropharynx or oral cavity. The vast majority of patients received adjuvant RT and concurrent chemotherapy. Overall, 34 (58.6 %) participants developed grade 3 OM after a median dose of 32 Gy. No patient experienced a grade ≥ 4 event. There was a correlation between the cell spreading assay area and grade 3 OM (p < 0.05), equivalent to approximately 0.5 Gy dose. Demographic and clinical parameters had no significant impact on the cell spreading assay (p > 0.05 for all). Conclusions It is necessary to establish reliable predictors of severe OM before treatment in H&N cancer to allow early management of treatment-related sequelae. This prospective trial illustrates that the intrinsic ex-vivo radiosensitivity of oral keratinocytes could be correlated with RT-induced OM in patients with H&N cancer. This novel predictor requires validation in larger prospective cohorts.

PURPOSE:This study evaluates the impact of partial volume effect (PVE) correction on [18F]fluoromisonidazole (FMISO) PET images, focusing on the conversion of standardized uptake values (SUV) to partial oxygen pressure (pO2) and the subsequent determination of hypoxic tumor volume (HTV). METHODS:FMISO PET images from 49 head and neck squamous cell carcinoma cases were retrospectively corrected for PVE and converted to pO2. A pO2 threshold of 10 mmHg was used to delineate the HTV (HTVpO2). Comparisons of pO2 distribution and HTVpO2 between corrected and uncorrected images were made, with pO2 distributions evaluated against published polarographic data. HTVpO2 was compared to HTV defined by the conventional tumor-to-muscle ratio (TMR) method (HTVTMR) in terms of volume and topography (DICE coefficient, Hausdorff distance, and center-of-gravity distance) across different TMR cutoff levels. The cutoff level where the segmentation results from both methods were most similar was identified (TMRbest). RESULTS:The PVE correction led to decreased minimum pO2, increased HTVpO2 and the identification of more hypoxic cases (HTV > 0). The pO2 distribution demonstrated improved alignment with published polarographic data. At TMRbest 1.6, the center-of-gravity distance between HTVTMR and HTVpO2 demonstrated a low median at 1.5 mm, while the wide range (0.0 to 9.6 mm) indicated high interpatient variability. The shape of HTV exhibited considerable variation with DICE 0.74 (0.03 to 1.00) and Hausdorff distance 8.5 mm (2.0 to 42.8 mm). CONCLUSIONS:PVE correction is recommended before converting SUV to pO2 for the spatially resolved quantification of hypoxia.

Purpose/Objective Recent studies have shown a potential function of the gut microbiome in the immunological modulation of anti-cancer treatments. However, the role of the oral microbiome in head-and-neck squamous cell carcinoma (HNSCC) patients undergoing radiotherapy in terms of radiation-induced toxicities as well as tumor response is largely unknown. Here, we examined a potential influence of the oral microbiome composition on acute radiation-induced mucositis and locoregional tumor control (LRC). Material/Methods Saliva samples of two independent prospective trials (SALIVA and ZiSStrans trial [DRKS00012947]), in which HNSCC patients undergoing (chemo)radiation were enrolled, were analyzed in terms of their oral microbiome composition. In both trials, unstimulated saliva was collected before the first radiotherapy application and stored at -80°C. Baseline oral microbiome was examined using V3-4 16S rRNA sequencing, and bioinformatic analyses were carried out in R (v4.3.1). Kaplan-Meier analyses were carried out regarding LRC. Results A total of 106 HNSCC patients (53 in the SALIVA trial, 53 in the ZiSStrans trial), who were treated with definitive (chemo)radiation, had stored saliva samples available and could be analyzed. Median age was 60 years (SALIVA) and 61 years (ZiSStrans), most common tumor localization was the oropharynx (n=25 in both trials), and majority of patients had a positive smoking history (n=29 [SALIVA], n=27 [ZiSStrans]). Fourty-four (83%) and 30 (57%) patients in the SALIVA and ZiSStrans trial developed acute grade 3-4 mucositis during treatment, respectively. Grade 3-4 mucositis occurred after a median radiation dose of 34 Gy (SALIVA) and 31.5 Gy (ZiSStrans). 2-year LRC rate was 69% and 72% in the SALIVA and ZiSStrans trial, respectively. No differences in alpha diversity were found in terms of patient age, sex, T stage, N stage, tumor localization and smoking status in both trials (p>0.05), neither did the beta diversity analysis reveal relevant differences between these groups. Furthermore, neither alpha nor beta diversity was associated with development of grade 3-4 mucositis in the two trials (p>0.05). In the ZiSStrans trial, Shannon index was significantly higher in patients with no locoregional recurrence after 2 years (p=.03), which was not validated in the SALIVA trial (p=0.35). Lower Lachnoanaerobaculum abundance (p=0.02 [SALIVA], p=0.03 [ZiSStrans], ALDEx2, Wilcoxon-test) were associated with increased 2-year locoregional recurrence rates in both the SALIVA and ZissTrans trial. 2-year LRC was 96% (SALIVA) and 85% (ZiSStrans) in patients with Lachnoanaerobaculum abundance above the median value versus 35% (SALIVA) and 58% (ZiSStrans) in patients with Lachnoanaerobaculum abundance below the median (p<0.05, log-rank). Conclusion While we could not find an association between the baseline oral microbiome and development of acute grade 3-4 mucositis, we identified higher Lachnoanaerobaculum abundance associated with increased LRC after radiotherapy in both independent prospective trials. In terms of oral mucositis, further in-depth analyses of the oral microbiome composition in both prospective trials are ongoing to examine potential associations between distinct bacterial genera and the onset of grade 3-4 mucositis. Prospective longitudinal analyses of the alterations in patients’ oral microbiome composition are necessary in order to improve the understanding of the complex interactions between the microbiome and the immune system in patients with HNSCC undergoing radiotherapy.

Background Both renal and osseous complications are common types of end organ damage in multiple myeloma (MM). Objective This study aims to present treatment options in the case of nephrological or osseous complications in MM. Materials and methods The work is based on a literature search of current international studies and review articles. Results and conclusion Renal and osseous complications are common forms of end organ damage in MM. Kidney damage in MM may be caused by toxic effects of free light chains that form aggregates in the tubules and lead to functional disorders, including acute or chronic kidney failure. Other diseases, such as amyloid light chain (AL) amyloidosis or monoclonal immunoglobulin deposition disease (MIDD), can also cause kidney damage. Treatment aims to preserve and/or improve kidney function and avoid dialysis. Supportive measures such as fluid replacement and avoidance of nephrotoxic substances are essential. Mechanical procedures such as (high-cutoff) hemodialysis support systemic anti-MM drug therapy. Multiple myeloma-associated bone disease results from an imbalance between osteoclast activity, which is enhanced by MM cells, and inhibited osteoblast activity. This leads to bone resorption, lytic lesions, and fractures. Whole-body CT, possibly supplemented by MRI or positron-emission tomography (PET)/CT, is used today. Treatment includes bisphosphonates, such as zoledronate and pamidronate, and denosumab to inhibit bone resorption. Rare side effects, such as kidney damage or osteonecrosis of the jaw, require special precautions. Pathological fractures can be surgically stabilized, and spinal cord compression requires decompression and radiation treatment.

TPS212 Background: Goal of our study is to evaluate the efficacy and safety of immunotherapy in combination with standard salvage radiation therapy (SRT) in patients with biochemical recurrence (BCR) or prostate-specific antigen (PSA) persistence after radical prostatectomy (RP). The combination of immunotherapy (IO) with radiation therapy might provide a clinical benefit to patients with recurrent prostate cancer due to an induction of increased activity of the immune system against cancerous tissue (abscopal effect). Primary endpoint is complete biochemical response (PSA level below detection level) 60 weeks after start of trial treatment, which further defines prognosis of patients. Further explorative endpoints like radiographic progression-free survival, PSA-nadir level and time to PSA-nadir, time to initiation of subsequent therapy (secondary ADT or NHA) and quality of life as well as adverse events will be evaluated. Methods: The trial is as a phase II, open-label, single arm monocenter trial which evaluates the combination of pembrolizumab as study medication in combination with SRT. Pembrolizumab will be administered in a three-weekly scheme up to one year of treatment. A concomitant ADT is administered in high-risk patients only (PSA > 0.7ng/ml or cN+ in imaging studies). All patients will be staged with PSMA PET-CT, if applicable. Additionally, blood and urine samples will be collected for correlative biomarker studies. A total of 49 patients are planned to be enrolled in this explorative study within 2 years. INCLUSION CRITERIA (excerpt) Histologically confirmed diagnosis of an adenocarcinoma of the prostate and a BCR or PSA persistence after RP. Histology of the RP specimen needs to fulfill the following criteria: adenocarcinoma of the prostate, Gleason score 7-10; pNX or pN0 or pN1 (max. 2 lymph nodes involved). Imaging within 30 days prior to study inclusion is mandatory (([68Ga] or [18F] PSMA PET-CT as standard imaging modality, alternatively CT abdomen and full-body bone scan). PSA value between ≥0.2 and ≤1.0 ng/ml, measured at least six weeks postoperatively. EXCLUSION CRITERIA (excerpt) Prior-therapy with an anti-PD-1, anti-PD-L1, or anti PD L2 agent or with an agent directed to another stimulatory or co-inhibitory T-cell receptor (e.g., CTLA-4, OX 40, CD137). Prior systemic anti-cancer therapy including investigational agents within 4 weeks prior to registration (like neo-adjuvant androgen deprivation therapy (ADT), secondary hormone ablation or taxan-based chemotherapy). Distant metastases or suspicious lymph nodes outside the lower pelvis in imaging with PSMA PET-CT (patients with PET positive bone lesions that are morphologically not clearly suspicious of metastases and would not change clinical practice can be included). Clinical trial information: NCT04931979.

BackgroundHead and neck cancers (HNCs) are very common malignancies, and treatment often requires multimodal approaches, including radiotherapy and chemotherapy. Patients with HNC often display a high symptom burden, both due to the disease itself and the adverse effects of the multimodal therapy. Close telemonitoring of symptoms and quality of life during the course of treatment may help to identify those patients requiring early medical support. ObjectiveThe App-Controlled Treatment Monitoring and Support for Patients With Head and Neck Cancer (APCOT) trial aimed to investigate the feasibility of integrating electronic patient-reported outcomes (ePROs) in the treatment surveillance pathway of patients with HNC during the course of their radiotherapy. Additionally, the influence of app-based ePRO monitoring on global and disease-specific quality of life and patient satisfaction with treatment was assessed. MethodsPatients undergoing radiotherapy for histologically proven HNCs at the Department of Radiation Oncology, University Medical Center Freiburg, Germany, were enrolled in this trial and monitored by weekly physician appointments. Patients were randomized between additional ePRO monitoring on each treatment day or standard-of-care monitoring. Feasibility of ePRO monitoring was defined as ≥80% of enrolled patients answering ≥80% of their daily app-based questions. Quality of life and patient satisfaction were assessed by the European Organisation for Research and Treatment of Cancer Core Quality of Life Questionnaire (QLQ-C30), the head and neck cancer module (H&N35), and the validated Patient Satisfaction Questionnaire Short Form (PSQ-18) at the completion of treatment and compared between trial arms. ResultsA total of 100 patients were enrolled in this trial, and 93 patients were evaluable. All patients (100%) in the experimental arm answered ≥80% of the ePRO questions during treatment, reaching the predefined threshold for the feasibility of ePRO monitoring (P<.001 in the binomial test). No clinical or patient-specific factor was found to influence feasibility. Global health and most domains of the general quality of life were comparable between trial arms, but an increased HNC-specific symptom burden was reported by patients undergoing ePRO surveillance. ePRO monitoring resulted in improved patient satisfaction regarding interpersonal manners (P=.01), financial aspects (P=.01), and time spent with a doctor (P=.01). ConclusionsThis trial demonstrated the feasibility of incorporating daily app-based ePRO surveillance for patients with HNC undergoing radiotherapy. Our data, for the first time, demonstrate that telemonitoring in this setting led to increased reporting of HNC-specific symptom burden and significantly improved several domains of patient satisfaction. Further analyses are needed to assess whether our findings hold true outside the context of a clinical trial. Trial RegistrationGerman Clinical Trials Register DRKS00020491; https://drks.de/search/en/trial/DRKS00020491

Purpose: To assess the robustness of prognostic biomarkers and molecular tumour subtypes developed for patients with head and neck squamous cell carcinoma (HNSCC) on cell -line derived HNSCC xenograft models, and to develop a novel biomarker signature by combining xenograft and patient datasets. Materials and methods: Mice bearing xenografts (n = 59) of ten HNSCC cell lines and a retrospective, multicentre patient cohort (n = 242) of the German Cancer Consortium -Radiation Oncology Group (DKTK-ROG) were included. All patients received postoperative radiochemotherapy (PORT -C). Gene expression analysis was conducted using GeneChip Human Transcriptome Arrays. Xenografts were stratified based on their molecular subtypes and previously established gene classifiers. The dose to control 50 % of tumours (TCD50) was compared between these groups. Using differential gene expression analyses combining xenograft and patient data, a gene signature was developed to define risk groups for the primary endpoint loco -regional control (LRC). Results: Tumours of mesenchymal subtype were characterized by a higher TCD50 (xenografts, p < 0.001) and lower LRC (patients, p < 0.001) compared to the other subtypes. Similar to previously published patient data, hypoxia- and radioresistance-related gene signatures were associated with high TCD50 values. A 2 -gene signature (FN1, SERPINE1) was developed that was prognostic for TCD50 (xenografts, p < 0.001) and for patient outcome in independent validation (LRC: p = 0.007). Conclusion: Genetic prognosticators of outcome for patients after PORT -C and subcutaneous xenografts after primary clinically relevant irradiation show similarity. The identified robust 2 -gene signature may help to guide patient stratification, after prospective validation. Thus, xenografts remain a valuable resource for translational research towards the development of individualized radiotherapy.

PURPOSE:To assess the relation of the previously reported classification of molecular subtypes to the outcome of patients with HNSCC treated with postoperative radio(chemo)therapy (PORT-C), and to assess the association of these subtypes with gene expressions reflecting known mechanisms of radioresistance.MATERIAL AND METHODS:Gene expression analyses were performed using the GeneChip Human Transcriptome Array 2.0 on a multicentre retrospective patient cohort (N = 128) of the German Cancer Consortium Radiation Oncology Group (DKTK-ROG) with locally advanced HNSCC treated with PORT-C. Tumours were assigned to four molecular subtypes, and correlation analyses between subtypes and clinical risk factors were performed. In addition, the classifications of eight genes or gene signatures related to mechanisms of radioresistance, which have previously shown an association with outcome of patients with HNSCC, were compared between the molecular subtypes. The endpoints loco-regional control (LRC) and overall survival (OS) were evaluated by log-rank tests and Cox regression.RESULTS:Tumours were classified into the four subtypes basal (19.5%), mesenchymal (18.8%), atypical (15.6%) and classical (14.1%). The remaining tumours could not be classified (32.0%). Tumours of the mesenchymal subtype showed a lower LRC compared to the other subtypes (p = 0.012). These tumours were associated with increased epithelial-mesenchymal transition (EMT) and overexpression of a gene signature enriched in DNA repair genes. The majority of the eight considered gene classifiers were significantly associated to LRC or OS in the whole cohort.CONCLUSION:Molecular subtypes, previously identified on HNSCC patients treated with primary radio(chemo)therapy or surgery, were related to LRC for patients treated with PORT-C, where mesenchymal tumours presented with worse prognosis. After prospective validation, subtype-based patient stratification, potentially in combination with other molecular classifiers, may be considered in future interventional studies in the context of personalised radiotherapy and may guide the development of combined treatment approaches.

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.

Introduction A range of referral criteria and scores have been developed in recent years to help with screening for the need of specialist palliative care (SPC) in advanced, incurable cancer patients. However, referral criteria have not yet been widely implemented in oncology, as they usually need to be revised by physicians or nurses with limited time resources. To develop an easily applicable screening for the need for SPC in incurable cancer inpatients, we aim to (a) test inter-rater reliability of multiprofessional expert opinion as reference standard for SPC need (phase I) and (b) explore the diagnostic validity of selected patient-reported outcome measures (PROMs) and routine data for the need of SPC (phase II). Methods and analysis Inclusion criteria for patients are metastatic or locally advanced, incurable cancer, ≥18 years of age and informed consent by patient or proxy. (Exclusion criteria: malignant haematological disease as main diagnosis). In phase I, three palliative care consultation teams (PCTs) of three German university hospitals assess the SPC need of 20 patient cases. Fleiss’ Kappa will be calculated for inter-rater reliability. In phase II, 208 patients are consecutively recruited in four inpatient oncology wards of Freiburg University Hospital. The PCT will provide assessment of SPC need. As potential referral criteria, patients complete PROMs and a selection of routine data on person, disease and treatment is documented. Logistic regression models and ROC analyses are employed to test their utility in screening for SPC need. Ethics and dissemination Our findings will be published in peer-reviewed journals and presented at national and international scientific meetings and congresses. Ethical approval was granted by the Ethics Committee of Albert-Ludwigs—University Freiburg, Germany (approval no. 20-1103). Trial registration number German Clinical Trials Register, DRKS00021686, registered on 17 December 2020.

PurposeThe aim of this study was to develop and validate a novel gene signature from full-transcriptome data using machine-learning approaches to predict loco-regional control (LRC) of patients with human papilloma virus (HPV)-negative locally advanced head and neck squamous cell carcinoma (HNSCC), who received postoperative radio(chemo)therapy (PORT-C).Materials and methodsGene expression analysis was performed using Affymetrix GeneChip Human Transcriptome Array 2.0 on a multicentre retrospective training cohort of 128 patients and an independent validation cohort of 114 patients from the German Cancer Consortium - Radiation Oncology Group (DKTK-ROG). Genes were filtered based on differential gene expression analyses and Cox regression. The identified gene signature was combined with clinical parameters and with previously identified genes related to stem cells and hypoxia. Technical validation was performed using nanoString technology.ResultsWe identified a 6-gene signature consisting of four individual genes CAV1, GPX8, IGLV3-25, TGFBI, and one metagene combining the highly correlated genes INHBA and SERPINE1. This signature was prognostic for LRC on the training data (ci = 0.84) and in validation (ci = 0.63) with a significant patient stratification into two risk groups (p = 0.005). Combining the 6-gene signature with the clinical parameters T stage and tumour localisation as well as the cancer stem cell marker CD44 and the 15-gene hypoxia-associated signature improved the validation performance (ci = 0.69, p = 0.001).ConclusionWe have developed and validated a novel prognostic 6-gene signature for LRC of HNSCC patients with HPV-negative tumours treated by PORT-C. After successful prospective validation the signature can be part of clinical trials on the individualization of radiotherapy.

Molecular precision oncology faces two major challenges: first, to identify relevant and actionable molecular variants in a rapidly changing field and second, to provide access to a broad patient population. Here, we report a four-year experience of the Molecular Tumor Board (MTB) of the Comprehensive Cancer Center Freiburg (Germany) including workflows and process optimizations. This retrospective single-center study includes data on 488 patients enrolled in the MTB from February 2015 through December 2018. Recommendations include individual molecular diagnostics, molecular stratified therapies, assessment of treatment adherence and patient outcomes including overall survival. The majority of MTB patients presented with stage IV oncologic malignancies (90.6%) and underwent an average of 2.1 previous lines of therapy. Individual diagnostic recommendations were given to 487 patients (99.8%). A treatment recommendation was given in 264 of all cases (54.1%) which included a molecularly matched treatment in 212 patients (43.4%). The 264 treatment recommendations were implemented in 76 patients (28.8%). Stable disease was observed in 19 patients (25.0%), 17 had partial response (22.4%) and five showed a complete remission (6.6%). An objective response was achieved in 28.9% of cases with implemented recommendations and for 4.5% of the total population (22 of 488 patients). By optimizing the MTB workflow, case-discussions per session increased significantly while treatment adherence and outcome remained stable over time. Our data demonstrate the feasibility and effectiveness of molecular-guided personalized therapy for cancer patients in a clinical routine setting showing a low but robust and durable disease control rate over time.

Purpose: Anal squamous cell carcinomas (ASCC) are increasing in frequency across the developed world. The 3-year disease-free survival (DFS) in patients with locally-advanced disease is approximately 60% after primary radiochemotherapy (RCT). There is a strong rationale for combining immunotherapy with RCT in patients with ASCC due to its association with human papilloma virus (HPV) infection. Methods/design: RADIANCE is an investigator initiated, prospective, multicenter, randomized phase II trial testing the addition of Durvalumab, a PD-L1 immune checkpoint inhibitor, to standard RCT in 178 patients with locally advanced ASCC (T2 > 4 cm Nany, cT3-4 and/or cN+). In the control arm, patients will be treated with standard mitomycin C (MMC)/5-fluorouracil (5-FU)-based RCT. Intensity-modulated radiotherapy (IMRT) will be applied as follows: PTV_A (primary tumor) T1-T2 < 4 cm N+: 28 x 1.9 Gy = 53.2 Gy; or T2 >= 4 cm, T3-4 Nany: 31 x 1.9 Gy = 58.9 Gy; PTV_N (involved node): 28 x 1.8 Gy = 50.4 Gy; and PTV_Elec (elective node): 28 x 1.43 Gy = 40.0 Gy over a period of 5,5-6 weeks. Concomitant chemotherapy will be administered using MMC with 5-FU during weeks 1 and 5 of radiotherapy (MMC 12 mg/m(2), day 1 [maximum single dose 20 mg]; 5-FU 1000 mg/m(2) days 1-4 and 29-32). In the experimental arm, Durvalmab (1500 mg absolute dose, intravenously) will be combined with the same RCT as in the control arm. Immunotherapy with Durvalumab will start 14 days before initiation of standard RCT, administered every four weeks (q4w) thereafter for a total of twelve doses. The primary endpoint is disease-free survival (DFS) after 3 years. Discussion: As ASCC is considered an immunogenically "hot" tumor due to its association with HPV infection, the combination of RCT with Durvalumab may improve tumor control and long-term clinical outcome in this patient collective compared to RCT alone. (C) 2020 The Author(s). Published by Elsevier B.V. on behalf of European Society for Radiotherapy and Oncology.

This article compares the expression and applicability of biomarkers, from single genes and gene signatures, identified in patients with locally advanced head and neck squamous cell carcinoma using the GeneChip Human Transcriptome Array 2.0, nCounter, and real-time PCR analyses. Two multicenter, retrospective cohorts of patients with head and neck squamous cell carcinoma from the German Cancer Consortium Radiation Oncology Group who received postoperative radiochemotherapy or primary radiochemotherapy were considered. Real-time PCR was performed for a limited number of 38 genes of the cohort who received postoperative radiochemotherapy only. Correlations between the methods were evaluated by the Spearman rank correlation coefficient. Patients were stratified based on the expression of putative cancer stem cell markers, hypoxia-associated gene signatures, and a previously developed seven-gene signature. Locoregional tumor control was compared between these patient subgroups using log-rank tests. Gene expressions obtained from nCounter analyses were moderately correlated to GeneChip analyses (median rho = approximately 0.68). A higher correlation was obtained between nCounter analyses and real-time PCR (median rho = 0.84). Significant associations with locoregional tumor control were observed for most of the considered biomarkers evaluated by GeneChip and nCounter analyses. In general, all applied biomarkers (single genes and gene signatures) classified approximately 70% to 85% of the patients similarly. Overall, gene signatures seem to be more robust and had a better transferability among different measurement methods.