Low-dose radiotherapy for greater trochanteric pain syndrome-a single-centre analysis.

PURPOSE: To determine predictive factors associated with a good response (GR) to and efficacy of low-dose radiotherapy (LDRT) in patients with greater trochanteric pain syndrome (GTPS). METHODS: Patients with GTPS were irradiated on a linear accelerator with 0.5-1.0 Gy per fraction to a total dose of 3.0-4.0 Gy per series. The endpoint was subjective good response (GR) to treatment 2 months after completion of the last LDRT series, defined as complete pain relief or marked improvement assessed using the von Pannewitz score. A positive response to steroid injection (SI) was defined as pain relief of at least 7 days. Patient and treatment-related characteristics were evaluated with respect to LDRT outcomes. RESULTS: Outcomes were assessed for 71 peritrochanteric spaces (PTSs; 65 patients, 48 females, with mean age of 63 [44-91] years). Prior SI had been given to 55 (77%) PTSs and 40 PTSs received two series of LDRT. Two months after completion of LDRT, GR was reported in 42 PTSs (59%). Two series of LDRT provided a significantly higher rate of GR than one series (72.5 vs. 42% PTSs, p = 0.015). Temporary pain relief after prior SI predicted GR to LDRT compared with PTSs which had not responded to SI (73 vs. 28% PTSs, p = 0.001). A regional structural abnormality, present in 34 PTSs (48%), was associated with a reduction of GR to LDRT (44 vs. 73% PTSs, p = 0.017). CONCLUSION: LDRT is an effective treatment for GTPS. Administration of two LDRT series, prior response to SI, and absence of structural abnormalities may predict significantly better treatment outcomes.

Therapy-Associated Saliva and Taste change Evaluation (TASTE) in head & neck cancer patients undergoing radiotherapy: a study protocol.

BACKGROUND: One of the main side effects of radiation therapy to the head and neck region is altered taste sensation. This causes significant morbidity and has profound effects on the quality of life (QoL) of patients. While radiation-associated toxicities like xerostomia and dysphagia are part of large investigations, data on taste impairment is sparse. Small cohort sizes in the majority of studies and a variety of analysis methods limit our current understanding of the underlying processes. None of the studies published to date used a taste-specific QoL questionnaire with differentiation of the different taste qualities (e.g. sour, bitter). Furthermore, data regarding the correlation of taste impairment with radiation-associated change in saliva composition is currently not available. The aim of the TASTE study is to fill this gap. Based on the acquired data, a normal tissue complication probability (NTCP) model for late radiation-associated taste impairment will be developed. METHODS: In this prospective, observational multicenter study 150 head and neck cancer patients undergoing radiation therapy will be recruited and undergo repetitive (semi-) objective and subjective assessment of their taste, smell and salivary function (questionnaires, taste and smell assessment, saliva analysis). Primary endpoint will be patient-reported taste impairment 12 months post radiation therapy using a standardized questionnaire. Secondary endpoints will include taste impairment measured using taste strips at 12 months and 2 years post radiation therapy. Differences between subgroups (radiation side, chemotherapy, etc.) and changes over time will be assessed while adjusting for confounding factors (e.g. age, sex, smoking history). DISCUSSION: This study sets out to further our understanding of taste impairment in patients undergoing radiation therapy to the head and neck region with the goal to prevent this common side effect in future patients. The results of the study may be used to evaluate taste-preserving radiotherapy for patients with head and neck cancer, which may significantly reduce the long-term burden in this patient cohort.

Theoretical evaluation of the impact of diverse treatment conditions by calculation of the tumor control probability (TCP) of simulated cervical cancer Hyperthermia-Radiotherapy (HT-RT) treatments in-silico.

INTRODUCTION: Hyperthermia (HT) induces various cellular biological processes, such as repair impairment and direct HT cell killing. In this context, in-silico biophysical models that translate deviations in the treatment conditions into clinical outcome variations may be used to study the extent of such processes and their influence on combined hyperthermia plus radiotherapy (HT + RT) treatments under varying conditions. METHODS: An extended linear-quadratic model calibrated for SiHa and HeLa cell lines (cervical cancer) was used to theoretically study the impact of varying HT treatment conditions on radiosensitization and direct HT cell killing effect. Simulated patients were generated to compute the Tumor Control Probability (TCP) under different HT conditions (number of HT sessions, temperature and time interval), which were randomly selected within margins based on reported patient data. RESULTS: Under the studied conditions, model-based simulations suggested a treatment improvement with a total CEM43 thermal dose of approximately 10 min. Additionally, for a given thermal dose, TCP increased with the number of HT sessions. Furthermore, in the simulations, we showed that the TCP dependence on the temperature/time interval is more correlated with the mean value than with the minimum/maximum value and that comparing the treatment outcome with the mean temperature can be an excellent strategy for studying the time interval effect. CONCLUSION: The use of thermoradiobiological models allows us to theoretically study the impact of varying thermal conditions on HT + RT treatment outcomes. This approach can be used to optimize HT treatments, design clinical trials, and interpret patient data.

Regional hyperthermia for soft tissue sarcoma - a survey on current practice, controversies and consensus among 12 European centers.

PURPOSE: To analyze the current practice of regional hyperthermia (RHT) for soft tissue sarcoma (STS) at 12 European centers to provide an overview, find consensuses and identify controversies necessary for future guidelines and clinical trials. METHODS: In this cross-sectional survey study, a 27-item questionnaire assessing clinical subjects and procedural details on RHT for STS was distributed to 12 European cancer centers for RHT. RESULTS: We have identified seven controversies and five consensus points. Of 12 centers, 6 offer both, RHT with chemotherapy (CTX) or with radiotherapy (RT). Two centers only offer RHT with CTX and four centers only offer RHT with RT. All 12 centers apply RHT for localized, high-risk STS of the extremities, trunk wall and retroperitoneum. However, eight centers also use RHT in metastatic STS, five in palliative STS, eight for superficial STS and six for low-grade STS. Pretherapeutic imaging for RHT treatment planning is used by 10 centers, 9 centers set 40-43 °C as the intratumoral target temperature, and all centers use skin detectors or probes in body orifices for thermometry. DISCUSSION: There is disagreement regarding the integration of RHT in contemporary interdisciplinary care of STS patients. Many clinical controversies exist that require a standardized consensus guideline and innovative study ideas. At the same time, our data has shown that existing guidelines and decades of experience with the technique of RHT have mostly standardized procedural aspects. CONCLUSIONS: The provided results may serve as a basis for future guidelines and inform future clinical trials for RHT in STS patients.

A patterns of care analysis of hyperthermia in combination with radio(chemo)therapy or chemotherapy in European clinical centers.

PURPOSE: The combination of hyperthermia (HT) with radio(chemo)therapy or chemotherapy (CT) is an established treatment strategy for specific indications. Its application in routine clinical practice in Europe depends on regulatory and local conditions. We conducted a survey among European clinical centers to determine current practice of HT. METHODS: A questionnaire with 22 questions was sent to 24 European HT centers. The questions were divided into two main categories. The first category assessed how many patients are treated with HT in combination with radio(chemo)therapy or CT for specific indications per year. The second category addressed which hyperthermia parameters are recorded. Analysis was performed using descriptive methods. RESULTS: The response rate was 71% (17/24) and 16 centers were included in this evaluation. Annually, these 16 centers treat approximately 637 patients using HT in combination with radio(chemo)therapy or CT. On average, 34% (range: 3-100%) of patients are treated in clinical study protocols. Temperature readings and the time interval between HT and radio(chemo)therapy or CT are recorded in 13 (81%) and 9 (56%) centers, respectively. The thermal dose quality parameter "cumulative equivalent minutes at 43 °C" (CEM43°C) is only evaluated in five (31%) centers for each HT session. With regard to treatment sequence, 8 (50%) centers administer HT before radio(chemo)therapy and the other 8 in the reverse order. CONCLUSION: There is a significant heterogeneity among European HT centers as to the indications treated and the recording of thermometric parameters. More evidence from clinical studies is necessary to achieve standardization of HT practice.

Radiotherapy combined with deep regional hyperthermia in elderly and frail patients with muscle-invasive bladder cancer: quality analysis of hyperthermia and impact on clinical results.

Purpose: Radiotherapy (RT) in combination with deep regional hyperthermia (HT) after transurethral removal of bladder tumor (TURBT) can be offered to elderly and frail patients with muscle-invasive bladder cancer (MIBC).Methods: In total, 21 patients (mean age 84 years) with unifocal or multifocal MIBC received radiation to a dose of 48-50 Gy/16-20 fractions with weekly HT. The primary endpoint was the variation in temperature metrics, thermal dose expressed as cumulative equivalent minutes at 43 °C when the measured temperature is T90 (CEM43T90) and net power applied in target volume per each HT session. Secondary endpoints were three-year overall survival (OS), disease-free survival (DFS), local progression-free survival (LPFS) and toxicity.Results: The temperature metrics, CEM43T90, mean and maximum net power applied did not differ significantly among the HT sessions of the 21 patients. With a median follow-up of 65 months, 52% (95% CI 32-72%) of patients had died 3 years after treatment. The three-year DFS and LPFS rates were 62% (95%CI 41-79%) and 81% (95%CI 60-92%), respectively. The three-year bladder preservation rate was 100%. Three out of four patients with local failure received a thermal dose CEM43T90 below a median of 2.4 min. The rates of acute and late grade-3 toxicities were 10% and 14%, respectively.Conclusion: The reproducibility of HT parameters between sessions was high. A moderately high CEM43T90 (> 2.4 min) for each HT session seems to be preferable for local control. RT combined with HT is a promising organ-preservation therapy for elderly and frail MIBC patients.

Hyperthermia in the treatment of high-risk soft tissue sarcomas: a systematic review.

BACKGROUND: The therapy of high-risk soft tissue sarcomas (STS) remains an interdisciplinary challenge. Regional hyperthermia (RHT) sparked interest as it has been shown to improve overall survival when added to perioperative chemotherapy (CTX). However, questions arise on how RHT should be optimally integrated into current multi-modal therapies. MATERIALS AND METHODS: We performed a systematic literature review according to Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Studies written in English and focused mainly on radiative RHT and superficial hyperthermia were evaluated and included. Studies including patients below the age of 18, with metastatic disease or review articles, were excluded. RESULTS: We identified 15 clinical reports from 1990 until July 2022. Three articles combined RHT + CTX, and twelve focused on combined RHT + radiotherapy (RT) or neoadjuvant chemoradiotherapy (CRT). Most treatments were based on invasive thermometry, and less on magnetic resonance imaging (MRI)-based, noninvasive thermometry for STS of the extremities. Perioperative chemotherapy was used for the combination of RHT and CTX, mostly Ifosfamide-based. The effectiveness of RT appeared to be increased by RHT, especially with two RHT sessions/week. The trimodal simultaneous approach of neoadjuvant RHT and CRT was also feasible. No significant toxicity of RHT was reported. CONCLUSIONS: The gathered data strengthen the beneficial role of RHT in the multimodal setting. Further expert consensus and clinical trials are required to determine the optimal integration of RHT in treating STS.

Postoperative radiotherapy versus no postoperative radiotherapy in patients with completely resected non-small-cell lung cancer and proven mediastinal N2 involvement (Lung ART): an open-label, randomised, phase 3 trial.

BACKGROUND: In patients with non-small-cell lung cancer (NSCLC), the use of postoperative radiotherapy (PORT) has been controversial since 1998, because of one meta-analysis showing a deleterious effect on survival in patients with pN0 and pN1, but with an unclear effect in patients with pN2 NSCLC. Because many changes have occurred in the management of patients with NSCLC, the role of three-dimensional (3D) conformal PORT warrants further investigation in patients with stage IIIAN2 NSCLC. The aim of this study was to establish whether PORT should be part of their standard treatment. METHODS: Lung ART is an open-label, randomised, phase 3, superiority trial comparing mediastinal PORT to no PORT in patients with NSCLC with complete resection, nodal exploration, and cytologically or histologically proven N2 involvement. Previous neoadjuvant or adjuvant chemotherapy was allowed. Patients aged 18 years or older, with an WHO performance status of 0-2, were recruited from 64 hospitals and cancer centres in five countries (France, UK, Germany, Switzerland, and Belgium). Patients were randomly assigned (1:1) to either the PORT or no PORT (control) groups via a web randomisation system, and minimisation factors were the institution, administration of chemotherapy, number of mediastinal lymph node stations involved, histology, and use of pre-treatment PET scan. Patients received PORT at a dose of 54 Gy in 27 or 30 daily fractions, on five consecutive days a week. Three dimensional conformal radiotherapy was mandatory, and intensity-modulated radiotherapy was permitted in centres with expertise. The primary endpoint was disease-free survival, analysed by intention to treat at 3 years; patients from the PORT group who did not receive radiotherapy and patients from the control group with no follow-up were excluded from the safety analyses. This trial is now closed. This trial is registered with ClinicalTrials.gov number, NCT00410683. FINDINGS: Between Aug 7, 2007, and July 17, 2018, 501 patients, predominantly staged with 18F-fluorodeoxyglucose (18F-FDG) PET (456 [91%]; 232 (92%) in the PORT group and 224 (90%) in the control group), were enrolled and randomly assigned to receive PORT (252 patients) or no PORT (249 patients). At the cutoff date of May 31, 2019, median follow-up was 4·8 years (IQR 2·9-7·0). 3-year disease-free survival was 47% (95% CI 40-54) with PORT versus 44% (37-51) without PORT, and the median disease-free survival was 30·5 months (95% CI 24-49) in the PORT group and 22·8 months (17-37) in the control group (hazard ratio 0·86; 95% CI 0·68-1·08; p=0·18). The most common grade 3-4 adverse events were pneumonitis (13 [5%] of 241 patients in the PORT group vs one [<1%] of 246 in the control group), lymphopenia (nine [4%] vs 0), and fatigue (six [3%] vs one [<1%]). Late-grade 3-4 cardiopulmonary toxicity was reported in 26 patients (11%) in the PORT group versus 12 (5%) in the control group. Two patients died from pneumonitis, partly related to radiotherapy and infection, and one patient died due to chemotherapy toxicity (sepsis) that was deemed to be treatment-related, all of whom were in the PORT group. INTERPRETATION: Lung ART evaluated 3D conformal PORT after complete resection in patients who predominantly had been staged using (18F-FDG PET-CT and received neoadjuvant or adjuvant chemotherapy. 3-year disease-free survival was higher than expected in both groups, but PORT was not associated with an increased disease-free survival compared with no PORT. Conformal PORT cannot be recommended as the standard of care in patients with stage IIIAN2 NSCLC. FUNDING: French National Cancer Institute, Programme Hospitalier de Recherche Clinique from the French Health Ministry, Gustave Roussy, Cancer Research UK, Swiss State Secretary for Education, Research, and Innovation, Swiss Cancer Research Foundation, Swiss Cancer League.

Tetramodal therapy with transurethral resection followed by chemoradiation in combination with hyperthermia for muscle-invasive bladder cancer: early results of a multicenter phase IIB study.

BACKGROUND: Transurethral resection of bladder tumor (TUR-BT) followed by chemoradiation (CRT) is a valid treatment option for patients with muscle-invasive bladder cancer (MIBC). This study aimed to investigate the efficacy of a tetramodal approach with additional regional hyperthermia (RHT). METHODS: Patients with stages T2-4 MIBC were recruited at two institutions. Treatment consisted of TUR-BT followed by radiotherapy at doses of 57-58.2 Gy with concurrent weekly platinum-based chemotherapy and weekly deep RHT (41-43 °C, 60 min) within two hours of radiotherapy. The primary endpoint was a complete response six weeks after the end of treatment. Further endpoints were cystectomy-free rate, progression-free survival (PFS), local recurrence-free survival (LRFS), overall survival (OS) and toxicity. Quality of life (QoL) was assessed at follow-up using the EORTC-QLQ-C30 and QLQ-BM30 questionnaires. Due to slow accrual, an interim analysis was performed after the first stage of the two-stage design. RESULTS: Altogether 27 patients were included in the first stage, of these 21 patients with a median age of 73 years were assessable. The complete response rate of evaluable patients six weeks after therapy was 93%. The 2-year cystectomy-free rate, PFS, LRFS and OS rates were 95%, 76%, 81% and 86%, respectively. Tetramodal treatment was well tolerated with acute and late G3-4 toxicities of 10% and 13%, respectively, and a tendency to improve symptom-related quality of life (QoL) one year after therapy. CONCLUSION: Tetramodal therapy of T2-T4 MIBC is promising with excellent local response, moderate toxicity and good QoL. This study deserves continuation into the second stage.

Successful salvage of recurrent leptomeningeal disease in large cell neuroendocrine lung cancer with stereotactic radiotherapy.

A 70-year old male with stage I large cell neuroendocrine carcinoma (LCNEC) of the lung underwent resection of a metachronous 5 cm brain metastasis and received postoperative hypofractionated stereotactic radiotherapy (hfSRT). Five sequential nodular leptomeningeal metastases up to 5.3 cm in diameter were diagnosed on MRI within 10 months and were treated with SRT. Currently the patient has no evidence of intracranial disease 24 months after last irradiation without chemotherapy or whole brain radiotherapy. This is the first report of sustained complete remission of multiple large leptomeningeal metastases achieved with hfSRT, highlighting this brain-sparing approach in selected patients with LCNEC lung cancer.

Quantification of thermal dose in moderate clinical hyperthermia with radiotherapy: a relook using temperature-time area under the curve (AUC).

BACKGROUND: Thermal dose in clinical hyperthermia reported as cumulative equivalent minutes (CEM) at 43 °C (CEM43) and its variants are based on direct thermal cytotoxicity assuming Arrhenius 'break' at 43 °C. An alternative method centered on the actual time-temperature plot during each hyperthermia session and its prognostic feasibility is explored. METHODS AND MATERIALS: Patients with bladder cancer treated with weekly deep hyperthermia followed by radiotherapy were evaluated. From intravesical temperature (T) recordings obtained every 10 secs, the area under the curve (AUC) was computed for each session for T > 37 °C (AUC > 37 °C) and T ≥ 39 °C (AUC ≥ 39 °C). These along with CEM43, CEM43(>37 °C), CEM43(≥39 °C), Tmean, Tmin and Tmax were evaluated for bladder tumor control. RESULTS: Seventy-four hyperthermia sessions were delivered in 18 patients (median: 4 sessions/patient). Two patients failed in the bladder. For both individual and summated hyperthermia sessions, the Tmean, CEM43, CEM43(>37 °C), CEM43(≥39 °C), AUC > 37 °C and AUC ≥ 39 °C were significantly lower in patients who had a local relapse. Individual AUC ≥ 39 °C for patients with/without local bladder failure were 105.9 ± 58.3 °C-min and 177.9 ± 58.0 °C-min, respectively (p = 0.01). Corresponding summated AUC ≥ 39 °C were 423.7 ± 27.8 °C-min vs. 734.1 ± 194.6 °C-min (p < 0.001), respectively. The median AUC ≥ 39 °C for each hyperthermia session in patients with bladder tumor control was 190 °C-min. CONCLUSION: AUC ≥ 39 °C for each hyperthermia session represents the cumulative time-temperature distribution at clinically defined moderate hyperthermia in the range of 39 °C to 45 °C. It is a simple, mathematically computable parameter without any prior assumptions and appears to predict treatment outcome as evident from this study. However, its predictive ability as a thermal dose parameter merits further evaluation in a larger patient cohort.

Radiomic biomarkers for head and neck squamous cell carcinoma.

Tumor heterogeneity is a well-known prognostic factor in head and neck squamous cell carcinoma (HNSCC). A major limitation of tissue- and blood-derived tumor markers is the lack of spatial resolution to image tumor heterogeneity. Tissue markers derived from tumor biopsies usually represent only a small tumor subregion at a single timepoint and are therefore often not representative of the tumors' biology or the biological alterations during and after treatment. Similarly, liquid biopsies give an overall picture of the tumors' secreted factors but completely lack any spatial resolution. Radiomics has the potential to give complete three-dimensional information about the tumor. We conducted a comprehensive literature search to assess the correlation of radiomics to tumor biology and treatment outcome in HNSCC and to assess current limitations of the radiomic biomarkers. In total, 25 studies that explored the ability of radiomics to predict tumor biology and phenotype in HNSCC and 28 studies that explored radiomics to predict post-treatment events were identified. Out of these 53 studies, only three failed to show a significant correlation. The major technical challenges are currently artifacts due to metal implants, non-standardized contrast injection, and delineation uncertainties. All studies to date were retrospective and none of the above-mentioned radiomics signatures have been validated in an independent cohort using an independent software implementation, which shows that transferability due to the numerous technical challenges is currently a major limitation. However, radiomics is a very young field and these studies hopefully pave the way for clinical implementation of radiomics for HNSCC in the future.

Dependency of the blood oxygen level dependent-response to hyperoxic challenges on the order of gas administration in intracranial malignancies.

PURPOSE: Literature reports contradicting results on the response of brain tumors to vascular stimuli measured in T2*-weighted MRI. Here, we analyzed the potential dependency of the MRI-response to (hypercapnic) hyperoxia on the order of the gas administration. METHODS: T2* values were quantified at 3 Tesla in eight consenting patients at rest and during inhalation of hyperoxic/hypercapnic gas mixtures. Patients were randomly divided into two groups undergoing different gas administration protocols (group A: medical air-pure oxygen-carbogen; group B: medical air-carbogen-pure oxygen). Mann-Whitney U test and Wilcoxon signed rank test have been used to proof differences in T2* regarding respiratory challenge or different groups, respectively. RESULTS: T2* values at rest for gray and white matter were 50.3 ± 2.6 ms and 46.1 ± 2.0 ms, respectively, and slightly increased during challenge. In tumor areas, T2* at rest were: necrosis = 74.1 ± 10.1 ms; edema = 60.3 ± 17.6 ms; contrast-enhancing lesions = 48.6 ± 20.7 ms; and solid T2-hyperintense lesions = 45.0 ± 3.0 ms. Contrast-enhancing lesions strongly responded to oxygen (+ 20.7%) regardless on the gas protocol (p = 0.482). However, the response to carbogen significantly depended on the order of gas administration (group A, + 18.6%; group B, - 6.4%, p = 0.042). In edemas, a different trend between group was found when breathing oxygen (group A, - 9.9%; group B, + 19.5%, p = 0.057). CONCLUSION: Preliminary results show a dependency of the T2* response of contrast-enhancing brain tumor lesions on the order of the gas administration. The gas administration protocol is an important factor in the interpretation of the T2*-response in areas of abnormal vascular growth.

Longitudinal PET imaging of tumor hypoxia during the course of radiotherapy.

Hypoxia results from an imbalance between oxygen supply and consumption. It is a common phenomenon in solid malignant tumors such as head and neck cancer. As hypoxic cells are more resistant to therapy, tumor hypoxia is an indicator for poor prognosis. Several techniques have been developed to measure tissue oxygenation. These are the Eppendorf O2 polarographic needle electrode, immunohistochemical analysis of endogenous (e.g., hypoxia-inducible factor-1α (HIF-1a)) and exogenous markers (e.g., pimonidazole) as well as imaging methods such as functional magnetic resonance imaging (e.g., blood oxygen level dependent (BOLD) imaging, T1-weighted imaging) and hypoxia positron emission tomography (PET). Among the imaging modalities, only PET is sufficiently validated to detect hypoxia for clinical use. Hypoxia PET tracers include 18F-fluoromisonidazole (FMISO), the most commonly used hypoxic marker, 18F-flouroazomycin arabinoside (FAZA), 18Ffluoroerythronitroimidazole (FETNIM), 18F-2-nitroimidazolpentafluoropropylacetamide (EF5) and 18F-flortanidazole (HX4). As technical development provides the opportunity to increase the radiation dose to subregions of the tumor, such as hypoxic areas, it has to be ensured that these regions are stable not only from imaging to treatment but also through the course of radiotherapy. The aim of this review is therefore to characterize the behavior of tumor hypoxia during radiotherapy for the whole tumor and for subregions by using hypoxia PET tracers, with focus on head and neck cancer patients.

Influence of inter-observer delineation variability on radiomics stability in different tumor sites.

BACKGROUND: Radiomics is a promising methodology for quantitative analysis and description of radiological images using advanced mathematics and statistics. Tumor delineation, which is still often done manually, is an essential step in radiomics, however, inter-observer variability is a well-known uncertainty in radiation oncology. This study investigated the impact of inter-observer variability (IOV) in manual tumor delineation on the reliability of radiomic features (RF). METHODS: Three different tumor types (head and neck squamous cell carcinoma (HNSCC), malignant pleural mesothelioma (MPM) and non-small cell lung cancer (NSCLC)) were included. For each site, eleven individual tumors were contoured on CT scans by three experienced radiation oncologists. Dice coefficients (DC) were calculated for quantification of delineation variability. RF were calculated with an in-house developed software implementation, which comprises 1404 features: shape (n = 18), histogram (n = 17), texture (n = 137) and wavelet (n = 1232). The IOV of RF was studied using the intraclass correlation coefficient (ICC). An ICC >0.8 indicates a good reproducibility. For the stable RF, an average linkage hierarchical clustering was performed to identify classes of uncorrelated features. RESULTS: Median DC was high for NSCLC (0.86, range 0.57-0.90) and HNSCC (0.72, 0.21-0.89), whereas it was low for MPM (0.26, 0-0.9) indicating substantial IOV. Stability rate of RF correlated with DC and depended on tumor site, showing a high stability in NSCLC (90% of total parameters), acceptable stability in HNSCC (59% of total parameters) and low stability in MPM (36% of total parameters). Shape features showed the weakest stability across all tumor types. Hierarchical clustering revealed 14 groups of correlated and stable features for NSCLC and 6 groups for both HNSCC and MPM. CONCLUSION: Inter-observer delineation variability has a relevant influence on radiomics analysis and is strongly influenced by tumor type. This leads to a reduced number of suitable imaging features.

Neutrophil-lymphocyte ratio complements volumetric staging as prognostic factor in patients treated with definitive radiotherapy for oropharyngeal cancer.

BACKGROUND: Volumetric tumor staging has been shown as superior prognostic tool compared to the conventional TNM system in patients undergoing definitive intensity-modulated radiotherapy (IMRT) for head and neck cancer. Recently, clinical immunoscores such as the neutrophil-lymphocyte ratio (NLR) have been investigated as prognostic markers in several tumor entities. The aim of this study was to assess the combined prognostic value of NLR and tumor volume in patients treated with IMRT for oropharyngeal cancer (OC). METHODS: Data on all consecutive patients treated for locally advanced or inoperable OC with IMRT from 2002-2011 was prospectively collected. Tumor volume was assessed based on the total gross tumor volume (tGTV) calculated by the treatment planning system volume algorithm. The NLR was collected by a retrospective analysis of differential blood count before initiation of therapy. RESULTS: Overall, 187 eligible patients were treated with a median IMRT dose of 69.6 Gy. Three-year recurrence-free survival (RFS) for low, intermediate, high and very high tumor volume groups was 88%, 74%, 62% and 25%, respectively (p = 0.007). Patients with elevated NLR (>4.68) showed a significantly decreased 3-year RFS of 44% vs. 81% (p < 0.001) and 3-year OS of 56% vs. 84% (p < 0.001). The NLR remained a significant prognostic factor for RFS and OS when tested among tumor volume groups. Univariate and multivariate regression analysis confirmed both tumor volume and NLR as independent prognostic factors. The NLR offered further statistically significant prognostic differentiation of the small/intermediate/large tumor volume groups. CONCLUSION: The NLR remains an independent prognostic factor for patients with OC undergoing radiotherapy independent of the tumor volume.

Comparison of PET and CT radiomics for prediction of local tumor control in head and neck squamous cell carcinoma.

PURPOSE: An association between radiomic features extracted from CT and local tumor control in the head and neck squamous cell carcinoma (HNSCC) has been shown. This study investigated the value of pretreatment functional imaging (18F-FDG PET) radiomics for modeling of local tumor control. MATERIAL AND METHODS: Data from HNSCC patients (n = 121) treated with definitive radiochemotherapy were used for model training. In total, 569 radiomic features were extracted from both contrast-enhanced CT and 18F-FDG PET images in the primary tumor region. CT, PET and combined PET/CT radiomic models to assess local tumor control were trained separately. Five feature selection and three classification methods were implemented. The performance of the models was quantified using concordance index (CI) in 5-fold cross validation in the training cohort. The best models, per image modality, were compared and verified in the independent validation cohort (n = 51). The difference in CI was investigated using bootstrapping. Additionally, the observed and radiomics-based estimated probabilities of local tumor control were compared between two risk groups. RESULTS: The feature selection using principal component analysis and the classification based on the multivariabale Cox regression with backward selection of the variables resulted in the best models for all image modalities (CICT = 0.72, CIPET = 0.74, CIPET/CT = 0.77). Tumors more homogenous in CT density (decreased GLSZMsize_zone_entropy) and with a focused region of high FDG uptake (higher GLSZMSZLGE) indicated better prognosis. No significant difference in the performance of the models in the validation cohort was observed (CICT = 0.73, CIPET = 0.71, CIPET/CT = 0.73). However, the CT radiomics-based model overestimated the probability of tumor control in the poor prognostic group (predicted = 68%, observed = 56%). CONCLUSIONS: Both CT and PET radiomics showed equally good discriminative power for local tumor control modeling in HNSCC. However, CT-based predictions overestimated the local control rate in the poor prognostic validation cohort, and thus, we recommend to base the local control modeling on the 18F-FDG PET.

Radiation recall dermatitis induced by sorafenib : A case study and review of the literature.

BACKGROUND: Radiation recall dermatitis (RRD) is an acute inflammatory reaction confined to previously irradiated skin, mainly subsequent to the administration of certain chemotherapeutics. Here we present a rare case of RRD induced by the oral multikinase inhibitor sorafenib. CASE REPORT: A 77-year-old male with hepatocellular carcinoma was irradiated at ten different sites for bone metastases with 20-36 Gray in 5-12 fractions from January to March 2015. Sorafenib 400 mg was administered twice daily from mid-March. One week later the patient presented with fever and erythematous lesions on the right upper arm, mandible, and trunk. All skin symptoms were confined to previously irradiated areas. After RRD was diagnosed by exclusion of other causes and skin biopsy, sorafenib was paused. With the administration of topical corticosteroids and oral antihistamines, the skin reaction subsided within several days. Sorafenib was readministered after 3 weeks, which did not lead to recurrence of RRD but did cause fluctuating fever. DISCUSSION: Only four other such cases have been reported in the literature and WHO pharmacovigilance database on individual case safety reports. The current report is the first to show a potential relationship between the severity of sorafenib-induced RRD and radiation dose, histopathological features, and simultaneous acute radiation dermatitis and mucositis. CONCLUSION: RRD induced by sorafenib is a rare phenomenon, but should be considered in patients showing erythematous skin lesions 1-2 weeks after initiation of the drug, predominantly in areas where skin has been irradiated with an equivalent dose ≥ 30 Gy. Discontinuation of sorafenib with possible readministration should be evaluated with respect to the clinical situation and severity of reaction.

Neoadjuvant chemotherapy and extrapleural pneumonectomy of malignant pleural mesothelioma with or without hemithoracic radiotherapy (SAKK 17/04): a randomised, international, multicentre phase 2 trial.

BACKGROUND: Postoperative hemithoracic radiotherapy has been used to treat malignant pleural mesothelioma, but it has not been assessed in a randomised trial. We assessed high-dose hemithoracic radiotherapy after neoadjuvant chemotherapy and extrapleural pneumonectomy in patients with malignant pleural mesothelioma. METHODS: We did this phase 2 trial in two parts at 14 hospitals in Switzerland, Belgium, and Germany. We enrolled patients with pathologically confirmed malignant pleural mesothelioma; resectable TNM stages T1-3 N0-2, M0; WHO performance status 0-1; age 18-70 years. In part 1, patients were given three cycles of neoadjuvant chemotherapy (cisplatin 75 mg/m(2) and pemetrexed 500 mg/m(2) on day 1 given every 3 weeks) and extrapleural pneumonectomy; the primary endpoint was complete macroscopic resection (R0-1). In part 2, participants with complete macroscopic resection were randomly assigned (1:1) to receive high-dose radiotherapy or not. The target volume for radiotherapy encompassed the entire hemithorax, the thoracotomy channel, and mediastinal nodal stations if affected by the disease or violated surgically. A boost was given to areas at high risk for locoregional relapse. The allocation was stratified by centre, histology (sarcomatoid vs epithelioid or mixed), mediastinal lymph node involvement (N0-1 vs N2), and T stage (T1-2 vs T3). The primary endpoint of part 1 was the proportion of patients achieving complete macroscopic resection (R0 and R1). The primary endpoint in part 2 was locoregional relapse-free survival, analysed by intention to treat. The trial is registered with ClinicalTrials.gov, number NCT00334594. FINDINGS: We enrolled patients between Dec 7, 2005, and Oct 17, 2012. Overall, we analysed 151 patients receiving neoadjuvant chemotherapy, of whom 113 (75%) had extrapleural pneumonectomy. Median follow-up was 54·2 months (IQR 32-66). 52 (34%) of 151 patients achieved an objective response. The most common grade 3 or 4 toxic effects were neutropenia (21 [14%] of 151 patients), anaemia (11 [7%]), and nausea or vomiting (eight [5%]). 113 patients had extrapleural pneumonectomy, with complete macroscopic resection achieved in 96 (64%) of 151 patients. We enrolled 54 patients in part 2; 27 in each group. The main reasons for exclusion were patient refusal (n=20) and ineligibility (n=10). 25 of 27 patients completed radiotherapy. Median total radiotherapy dose was 55·9 Gy (IQR 46·8-56·0). Median locoregional relapse-free survival from surgery, was 7·6 months (95% CI 4·5-10·7) in the no radiotherapy group and 9·4 months (6·5-11·9) in the radiotherapy group. The most common grade 3 or higher toxic effects related to radiotherapy were nausea or vomiting (three [11%] of 27 patients), oesophagitis (two [7%]), and pneumonitis (two [7%]). One patient died of pneumonitis. We recorded no toxic effects data for the control group. INTERPRETATION: Our findings do not support the routine use of hemithoracic radiotherapy for malignant pleural mesothelioma after neoadjuvant chemotherapy and extrapleural pneumonectomy. FUNDING: Swiss Group for Clinical Cancer Research, Swiss State Secretariat for Education, Research and Innovation, Eli Lilly.

Radiation-associated changes in saliva composition of head and neck cancer patients: A systematic review.

Xerostomia is a common radiation-associated toxicity in patients with head and neck cancer. Although several studies examined the decrease in saliva production due to radiotherapy (RT) and investigated the factors associated with this side effect, little is known about the change in radiation-associated saliva composition. This systematic review is the first to summarize existing data and give an overview of the change in pH/buffer capacity, electrolytes, proteins, enzymes, and mucins due to radiation to the salivary glands. Literature search was performed in PubMed and Embase with 47 articles finally eligible for the review, analyzing the saliva composition at several time points before, during and/or after RT, or comparing findings in irradiated patients to a healthy control group. Overall, RT leads to a substantial decrease in salivary pH and buffer capacity. For sodium, chloride and calcium ion, as well as amylase, an increased concentration or activity during RT was reported in most of the studies, followed by a subsequent decrease either already during RT or after the end of treatment. Different trends have been described for the total protein concentration during and after RT. Lactoferrin, however, increased considerably, especially in the first phase of RT. Mucin 5B (MUC5B) concentrations showed a slight increase during RT and concentrations around baseline values again six months post-radiotherapy.