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.

Histopathologically confirmed radiation-induced damage of the brain - an in-depth analysis of radiation parameters and spatio-temporal occurrence.

BACKGROUND: Radiation-induced damage (RID) after radiotherapy (RT) of primary brain tumors and metastases can be challenging to clinico-radiographically distinguish from tumor progression. RID includes pseudoprogression and radiation necrosis; the latter being irreversible and often associated with severe symptoms. While histopathology constitutes the diagnostic gold standard, biopsy-controlled clinical studies investigating RID remain limited. Whether certain brain areas are potentially more vulnerable to RID remains an area of active investigation. Here, we analyze histopathologically confirmed cases of RID in relation to the temporal and spatial dose distribution. METHODS: Histopathologically confirmed cases of RID after photon-based RT for primary or secondary central nervous system malignancies were included. Demographic, clinical, and dosimetric data were collected from patient records and treatment planning systems. We calculated the equivalent dose in 2 Gy fractions (EQD22) and the biologically effective dose (BED2) for normal brain tissue (α/ß ratio of 2 Gy) and analyzed the spatial and temporal distribution using frequency maps. RESULTS: Thirty-three patients were identified. High-grade glioma patients (n = 18) mostly received one normofractionated RT series (median cumulative EQD22 60 Gy) to a large planning target volume (PTV) (median 203.9 ccm) before diagnosis of RID. Despite the low EQD22 and BED2, three patients with an accelerated hyperfractionated RT developed RID. In contrast, brain metastases patients (n = 15; 16 RID lesions) were often treated with two or more RT courses and with radiosurgery or fractionated stereotactic RT, resulting in a higher cumulative EQD22 (median 162.4 Gy), to a small PTV (median 6.7 ccm). All (n = 34) RID lesions occurred within the PTV of at least one of the preceding RT courses. RID in the high-grade glioma group showed a frontotemporal distribution pattern, whereas, in metastatic patients, RID was observed throughout the brain with highest density in the parietal lobe. The cumulative EQD22 was significantly lower in RID lesions that involved the subventricular zone (SVZ) than in lesions without SVZ involvement (median 60 Gy vs. 141 Gy, p = 0.01). CONCLUSIONS: Accelerated hyperfractionated RT can lead to RID despite computationally low EQD22 and BED2 in high-grade glioma patients. The anatomical location of RID corresponded to the general tumor distribution of gliomas and metastases. The SVZ might be a particularly vulnerable area.

ESTRO ACROP consensus recommendation on the target volume definition for radiation therapy of macroscopic prostate cancer recurrences after radical prostatectomy.

Background: The European Society for Radiotherapy & Oncology (ESTRO) Advisory Committee for Radiation Oncology Practice (ACROP) panel on prostate bed delineation reflected on macroscopic local recurrences in patients referred for postoperative radiotherapy (PORT), a challenging situation without standardized approach, and decided to propose a consensus recommendation on target volume selection and definition. Methods: An ESTRO ACROP contouring consensus panel consisting of 12 radiation oncologists and one radiologist, all with subspecialty expertise in prostate cancer, was established. Participants were asked to delineate the prostate bed clinical target volumes (CTVs) in two separate clinically relevant scenarios: a local recurrence at the seminal vesicle bed and one apically at the level of the anastomosis. Both recurrences were prostate-specific membrane antigen (PSMA)-avid and had an anatomical correlate on magnetic resonance imaging (MRI). Participants also answered case-specific questionnaires addressing detailed recommendations on target delineation. Discussions via electronic mails and videoconferences for final editing and consensus were performed. Results: Contouring of the two cases confirmed considerable variation among the panelists. Finally, however, a consensus recommendation could be agreed upon. Firstly, it was proposed to always delineate the entire prostate bed as clinical target volume and not the local recurrence alone. The panel judged the risk of further microscopic disease outside of the visible recurrence too high to safely exclude the rest of the prostate bed from the CTV. A focused, "stereotactic" approach should be reserved for re-irradiation after previous PORT. Secondly, the option of a focal boost on the recurrence was discussed. Conclusion: Radiation oncologists are increasingly confronted with macroscopic local recurrences visible on imaging in patients referred for postoperative radiotherapy. It was recommended to always delineate and irradiate the entire prostate bed, and not the local recurrence alone, whatever the exact location of that recurrence. Secondly, specific dose-escalation on the macroscopic recurrence should only be considered if an anatomic correlate is visible. Such a focal boost is probably feasible, provided that OAR constraints are prioritized. Possible dose is also dependent on the location of the recurrence. Its potential benefit should urgently be investigated in prospective clinical trials.

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.

ESTRO ACROP guideline on prostate bed delineation for postoperative radiotherapy in prostate cancer.

Purpose/Objective: Radiotherapy to the prostate bed is a potentially curative salvage option after radical prostatectomy. Although prostate bed contouring guidelines are available in the literature, important variabilities exist. The objective of this work is to provide a contemporary consensus guideline for prostate bed delineation for postoperative radiotherapy. Methods: An ESTRO-ACROP contouring consensus panel consisting of 11 radiation oncologists and one radiologist, all with known subspecialty expertise in prostate cancer, was established. Participants were asked to delineate the prostate bed clinical target volumes (CTVs) in 3 separate clinically relevant scenarios: adjuvant radiation, salvage radiation with PSA progression, and salvage radiation with persistently elevated PSA. These cases focused on the presence of positive surgical margin, extracapsular extension, and seminal vesicles involvement. None of the cases had radiographic evidence of local recurrence on imaging. A single computed tomography (CT) dataset was shared via FALCON platform and contours were performed using EduCaseTM software. Contours were analyzed qualitatively using heatmaps which provided a visual assessment of controversial regions and quantitatively analyzed using Sorensen-Dice similarity coefficients. Participants also answered case-specific questionnaires addressing detailed recommendations on target delineation. Discussions via electronic mails and videoconferences for final editing and consensus were performed. Results: The mean CTV for the adjuvant case was 76 cc (SD = 26.6), salvage radiation with PSA progression was 51.80 cc (SD = 22.7), and salvage radiation with persistently elevated PSA 57.63 cc (SD = 25.2). Compared to the median, the mean Sorensen-Dice similarity coefficient for the adjuvant case was 0.60 (SD 0.10), salvage radiation with PSA progression was 0.58 (SD = 0.12), and salvage radiation with persistently elevated PSA 0.60 (SD = 0.11). A heatmap for each clinical scenario was generated. The group agreed to proceed with a uniform recommendation for all cases, independent of the radiotherapy timing. Several controversial areas of the prostate bed CTV were identified based on both heatmaps and questionnaires. This formed the basis for discussions via videoconferences where the panel achieved consensus on the prostate bed CTV to be used as a novel guideline for postoperative prostate cancer radiotherapy. Conclusion: Variability was observed in a group formed by experienced genitourinary radiation oncologists and a radiologist. A single contemporary ESTRO-ACROP consensus guideline was developed to address areas of dissonance and improve consistency in prostate bed delineation, independent of the indication.There is important variability in existing contouring guidelines for postoperative prostate bed (PB) radiotherapy (RT) after radical prostatectomy. This work aimed at providing a contemporary consensus guideline for PB delineation. An ESTRO ACROP consensus panel including radiation oncologists and a radiologist, all with known subspecialty expertise in prostate cancer, delineated the PB CTV in 3 scenarios: adjuvant RT, salvage RT with PSA progression, and salvage RT with persistently elevated PSA. None of the cases had evidence of local recurrence. Contours were analysed qualitatively using heatmaps for visual assessment of controversial regions and quantitatively using Sorensen-Dice coefficient. Case-specific questionnaires were also discussed via e-mails and videoconferences for consensus. Several controversial areas of the PB CTV were identified based on both heatmaps and questionnaires. This formed the basis for discussions via videoconferences. Finally, a contemporary ESTRO-ACROP consensus guideline was developed to address areas of dissonance and improve consistency in PB delineation, independent of the indication.

Regional hyperthermia with cisplatin added to gemcitabine versus gemcitabine in patients with resected pancreatic ductal adenocarcinoma: The HEAT randomised clinical trial.

BACKGROUND: Regional hyperthermia (RHT) with cisplatin added to gemcitabine showed efficacy in gemcitabine-pre-treated patients with advanced pancreatic ductal adenocarcinoma. We conducted a randomised clinical trial to investigate RHT with cisplatin added to gemcitabine (GPH) compared with gemcitabine (G) in the adjuvant setting of resected pancreatic ductal adenocarcinoma. METHODS: This randomised, multicentre, open-label trial randomly assigned patients to either GPH (gemcitabine 1000 mg/m2 on day 1, 15 and cisplatin 25 mg/m2 with RHT on day 2, 3 and 15,16) or to G (gemcitabine 1000 mg/m2 on day 1,8,15), four-weekly over six cycles. Disease-free survival (DFS) was the primary end-point. Secondary end-points included overall survival (OS) and safety. RESULTS: A total of 117 eligible patients (median age, 63 years) were randomly allocated to treatment (57 GPH; 60 G). With a follow-up time of 56.6 months, the median DFS was 12.7 compared to 11.2 months for GPH and G, respectively (p = 0.394). Median post-recurrence survival was significantly prolonged in the GPH-group (15.3 versus 9.8 months; p = 0.031). Median OS reached 33.2 versus 25.2 months (p = 0.099) with 5-year survival rates of 28.4% versus 18.7%. Excluding eight patients who received additional capecitabine in the G-arm (investigators choice), median OS favoured GPH (p = 0.052). Adverse events CTCAE (Common Terminology Criteria for Adverse Events) grade ≥3 occurred in 61.5% (GPH) versus 63.6% (G) of patients. Two patients in the G-group died because of treatment-related toxic effects. CONCLUSIONS: The randomised controlled Hyperthermia European Adjuvant Trial study failed to demonstrate a significant difference in DFS. However, it suggests a difference in post-recurrence survival and a trend for improved OS. CLINICALTRIALS: gov, number NCT01077427.

Genomic Classifiers in Personalized Prostate Cancer Radiation Therapy Approaches: A Systematic Review and Future Perspectives Based on International Consensus.

Current risk-stratification systems for prostate cancer (PCa) do not sufficiently reflect the disease heterogeneity. Genomic classifiers (GC) enable improved risk stratification after surgery, but less data exist for patients treated with definitive radiation therapy (RT) or RT in oligo-/metastatic disease stages. To guide future perspectives of GCs for RT, we conducted (1) a systematic review on the evidence of GCs for patients treated with RT and (2) a survey of experts using the Delphi method, addressing the role of GCs in personalized treatments to identify relevant fields of future clinical and translational research. We performed a systematic review and screened ongoing clinical trials on ClinicalTrials.gov. Based on these results, a multidisciplinary international team of experts received an adapted Delphi method survey. Thirty-one and 30 experts answered round 1 and round 2, respectively. Questions with ≥75% agreement were considered relevant and included in the qualitative synthesis. Evidence for GCs as predictive biomarkers is mainly available to the postoperative RT setting. Validation of GCs as prognostic markers in the definitive RT setting is emerging. Experts used GCs in patients with PCa with extensive metastases (30%), in postoperative settings (27%), and in newly diagnosed PCa (23%). Forty-seven percent of experts do not currently use GCs in clinical practice. Expert consensus demonstrates that GCs are promising tools to improve risk-stratification in primary and oligo-/metastatic patients in addition to existing classifications. Experts were convinced that GCs might guide treatment decisions in terms of RT-field definition and intensification/deintensification in various disease stages. This work confirms the value of GCs and the promising evidence of GC utility in the setting of RT. Additional studies of GCs as prognostic biomarkers are anticipated and form the basis for future studies addressing predictive capabilities of GCs to optimize RT and systemic therapy. The expert consensus points out future directions for GC research in the management of PCa.

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.

Radiofrequency Electromagnetic Fields Cause Non-Temperature-Induced Physical and Biological Effects in Cancer Cells.

Non-temperature-induced effects of radiofrequency electromagnetic fields (RF) have been controversial for decades. Here, we established measurement techniques to prove their existence by investigating energy deposition in tumor cells under RF exposure and upon adding amplitude modulation (AM) (AMRF). Using a preclinical device LabEHY-200 with a novel in vitro applicator, we analyzed the power deposition and system parameters for five human colorectal cancer cell lines and measured the apoptosis rates in vitro and tumor growth inhibition in vivo in comparison to water bath heating. We showed enhanced anticancer effects of RF and AMRF in vitro and in vivo and verified the non-temperature-induced origin of the effects. Furthermore, apoptotic enhancement by AM was correlated with cell membrane stiffness. Our findings not only provide a strategy to significantly enhance non-temperature-induced anticancer cell effects in vitro and in vivo but also provide a perspective for a potentially more effective tumor therapy.

Dual Targeting of the EGFR/HER2 Pathway in Combination with Systemic Chemotherapy in Refractory Pancreatic Cancer-The CONKO-008 Phase I Investigation.

BACKGROUND: Primary objective of this present trial was to define the maximum tolerable dose of lapatinib in combination with oxaliplatin, 5-fluorouracil, and folinic acid (OFF) in refractory pancreatic cancer. The secondary objective was to assess the safety and efficacy of lapatinib plus OFF. METHODS: We conducted a phase I trial using an accelerated dose escalation design in patients with refractory pancreatic cancer. Lapatinib was given on days 1 to 42 in combination with folinic acid 200 mg/m2 day + 5-fluorouracil 2000 mg/m2 (24 h) on days 1, 8, 15, and 22, and oxaliplatin 85 mg/m2 days 8 and 22 of a 43-day cycle (OFF). Toxicity and efficacy were evaluated. RESULTS: In total, eighteen patients were enrolled: dose level 1 (1000 mg) was assigned to seven patients, dose level 2 (1250 mg), five patients; and dose level 3 (1500 mg), six patients. Dose-limiting toxicities were diarrhea and/or neutropenic enterocolitis observed in two of six patients: one diarrhea III°, one diarrhea IV°, as well as neutropenic enterocolitis. The maximum tolerable dose of lapatinib was 1250 mg OD. CONCLUSIONS: The combination of lapatinib 1250 mg OD with platinum-containing chemotherapy is safe and feasible in patients with refractory pancreatic cancer and warrants further investigation.

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.

Radiotherapy for hormone-sensitive prostate cancer with synchronous low burden of distant metastases.

PURPOSE: The DEGRO Expert Commission on Prostate Cancer has revised the indication for radiation therapy of the primary prostate tumor in patients with synchronous distant metastases with low metastatic burden. METHODS: The current literature in the PubMed database was reviewed regarding randomized evidence on radiotherapy of the primary prostate tumor with synchronous low metastatic burden. RESULTS: In total, two randomized trials were identified. The larger study, the STAMPEDE trial, demonstrated an absolute survival benefit of 8% after 3 years for patients with low metastatic burden treated with standard of care (SOC) and additional radiotherapy (RT) (EQD2 ≤ 72 Gy) of the primary tumor. Differences in the smaller Horrad trial were not statistically significant, although risk reduction in the subgroup (< 5 bone metastases) was equal to STAMPEDE. The STOPCAP meta-analysis of both trials demonstrated the benefit of local radiotherapy for up to 4 bone lesions and an additional subanalysis of STAMPEDE also substantiated this finding in cases with M1a-only metastases. CONCLUSION: Therefore, due to the survival benefit after 3 years, current practice is changing. New palliative SOC is radiotherapy of the primary tumor in synchronously metastasized prostate cancer with low metastatic burden (defined as ≤ 4 bone metastases, with or without distant nodes) or in case of distant nodes only detected by conventional imaging.

Oncologic Thermoradiotherapy: Need for Evidence, Harmonisation, and Innovation.

The road of acceptance of oncologic thermotherapy/hyperthermia as a synergistic modality in combination with standard oncologic therapies is still bumpy [...].

Randomized Pilot Trial Using External Yarrow Liver Compress Applications With Metastatic Cancer Patients Suffering From Fatigue: Evaluation of Sympathetic Modulation by Heart Rate Variability Analysis.

BACKGROUND: Liver compresses are commonly applied in complementary medicine during cancer treatment and are believed to have an energizing effect. We conducted a pilot study to investigate the influence of external application of yarrow liver compresses on the autonomous nervous system by analyzing the heart rate variability (HRV) in metastatic cancer patients undergoing radiation therapy and suffering from cancer-related fatigue (CRF). METHODS: A randomized pilot trial was undertaken with patients suffering from CRF receiving palliative radiation therapy for bone or brain metastasis over 2 weeks. CRF patients were randomized into an intervention group receiving yarrow liver compresses and a control group receiving no external application. HRV was analyzed at the beginning (T1) and end (T2) period of the study during daytime (d) and nighttime (n) in both groups and quantified using time-, frequency-, and nonlinear dynamics domains. RESULTS: A total of 39 patients were randomized between September 2017 and August 2019 and a total of 20 patients (10 per group) were available for analysis. For both groups, significant differences in HRV analyses were found in the comparison over the timeline between the first and second measurement (T1d→T2d) during daytime. Specifically, the intervention group showed decreased HRV and complexity of heart rate regulation, indicating increased sympathetic activity at time T2d, whereas the control group showed increased HRV and complexity of heart rate regulation, indicating increased vagal activity at time T2d. Furthermore, the observed HRV analyses showed almost no significant differences between the 2 groups in a direct comparison at the beginning and the end of the study (exception: T2d). CONCLUSIONS: Yarrow liver compresses led to increased sympathetic activity during daytime in the intervention group, whereas in the control group, which did not receive any external application, increased parasympathetic activity was observed.

PSMA-PET- and MRI-Based Focal Dose Escalated Radiation Therapy of Primary Prostate Cancer: Planned Safety Analysis of a Nonrandomized 2-Armed Phase 2 Trial (ARO2020-01).

PURPOSE: The bicentric HypoFocal phase 2 trial investigates the implementation of molecular imaging with positron-emission tomography targeting prostate-specific membrane antigen (PSMA-PET) into modern focal dose-escalation radiation therapy (RT) concepts in 2 nonrandomized arms. We present the planned safety analysis after 6 months of follow-up. MATERIALS AND METHODS: Intermediate- and high-risk localized primary prostate cancer patients staged with multiparametric magnet resonance tomography and PSMA-PET were either treated with focal dose-escalated moderately hypofractionated RT (arm A) or single fraction high-dose-rate brachytherapy followed by external beam RT (arm B). PSMA-PET was used in addition to primary prostate cancer to define the intraprostatic gross tumor volume. Gastrointestinal and genitourinary toxicities were assessed according to Common Toxicity Criteria for Adverse Events (version 5.0) criteria. International Prostate Symptom Score was measured and quality of life assessed with European Organisation for Research and Treatment of Cancer questionnaires QLQ-PR25/-PR30. We enrolled 25 patients in each study arm. RESULTS: The implementation of PET-information led to large median volumes for dose escalation: 10.2 mL in arm A and 6.8 mL in Arm B. RT dose-escalation was feasible in all patients of arm A with up to 75 Gy (20 fractions) and in 23 patients with up to 19 Gy (1 fraction) in arm B. Toxicities, International Prostate Symptom Scores, and European Organisation for Research and Treatment of Cancer quality of life scores were not significantly different between baselines and 6 months follow-up in both arms. No grade 3 toxicities were observed at 6 months follow-up. CONCLUSIONS: This is the first prospective data supporting the feasibility of PSMA-PET-implementation into definitive focal dose-escalated RT. Patients maintained a good quality of life and a low toxicity profile after 6 months of follow-up.

Experimental and computational evaluation of capacitive hyperthermia.

OBJECTIVE: Hyperthermia as an enhancer of radio- and/or chemotherapy has been confirmed by various trials. Quite a few positive randomized trials have been carried out with capacitive hyperthermia systems (CHS), even though specific absorption rates (SAR) in deep regions are known to be inferior to the established annular-phased array techniques. Due to a lack of systematic SAR measurements for current capacitive technology, we performed phantom measurements in combination with simulation studies. MATERIALS AND METHODS: According to the current guidelines, homogeneous and inhomogeneous agarose phantoms were manufactured for the commercial CHS Celsius42. Temperature/time curves were registered, and specific absorption rate (SAR) profiles and distributions were derived using the temperature gradient method. We implemented models for electrodes and phantom setups for simulation studies using Sim4Life. RESULTS: For a standard total power of 200 W, we measured effective SAR until depths of 6-8 cm in a homogeneous phantom, which indicates fair heating conditions for tumor diseases in superficial and intermediate depths. A fat layer of 1 cm strongly weakens the SAR, but 10-20 W/kg are still achieved in intermediate to deep regions (2-10 cm). In the phantom setup with integrated bone, we measured low SAR of 5-10 W/kg in the cancellous bone. Our simulations could fairly describe the measured SAR distributions, but predict tendentially higher SAR than measured. Additional simulations suggest that we would achieve higher SAR with vital fatty tissue and bone metastases in clinical situations. CONCLUSION: Capacitive systems are suitable to heat superficial and medium-deep tumors as well as some bone metastases, and CHS application is feasible for a specific class of patients with pelvic and abdominal tumors. These findings are consistent with positive clinical studies.

Clinical Evidence for Thermometric Parameters to Guide Hyperthermia Treatment.

Hyperthermia (HT) is a cancer treatment modality which targets malignant tissues by heating to 40-43 °C. In addition to its direct antitumor effects, HT potently sensitizes the tumor to radiotherapy (RT) and chemotherapy (CT), thereby enabling complete eradication of some tumor entities as shown in randomized clinical trials. Despite the proven efficacy of HT in combination with classic cancer treatments, there are limited international standards for the delivery of HT in the clinical setting. Consequently, there is a large variability in reported data on thermometric parameters, including the temperature obtained from multiple reference points, heating duration, thermal dose, time interval, and sequence between HT and other treatment modalities. Evidence from some clinical trials indicates that thermal dose, which correlates with heating time and temperature achieved, could be used as a predictive marker for treatment efficacy in future studies. Similarly, other thermometric parameters when chosen optimally are associated with increased antitumor efficacy. This review summarizes the existing clinical evidence for the prognostic and predictive role of the most important thermometric parameters to guide the combined treatment of RT and CT with HT. In conclusion, we call for the standardization of thermometric parameters and stress the importance for their validation in future prospective clinical studies.

Adherence to Contouring and Treatment Planning Requirements Within a Multicentric Trial: Results of the Quality Assurance of the SAKK 09/10 trial.

PURPOSE: To evaluate the results of the radiation therapy (RT) quality assurance (QA) program of the phase 3 randomized SAKK 09/10 trial in patients with biochemically recurrent prostate cancer after prostatectomy. METHODS AND MATERIALS: Within the Schweizerische Arbeitsgemeinschaft für Klinische Krebsforschung (SAKK) 09/10 trial testing 64-Gy versus 70-Gy salvage RT, a central collection of treatment plans was performed and thoroughly reviewed by a dedicated medical physicist and radiation oncologist. Adherence to the treatment protocol and specifically to the European Organization for the Research and Treatment of Cancer (EORTC) guidelines for target volume definition (classified as deviation observed yes vs no) and its potential correlation with acute and late toxicity (Common Terminology Criteria for Adverse Events version 4.0) and freedom from biochemical progression (FFBP) were investigated. RESULTS: The treatment plans for 344 patients treated between February 2011 and April 2014 depicted important deviations from the EORTC guidelines and the recommendations per trial protocol. For example, in up to half of the cases, the delineated structures deviated from the protocol (eg, prostate bed in 48.8%, rectal wall [RW] in 41%). In addition, variations in clinical target volume (CTV) and planning target volume (PTV) occurred frequently (eg, CTV and PTV deviations in up to 42.4% and 25.9%, respectively). The detected deviations showed a significant association with a lower risk of grade ≥2 gastrointestinal acute toxicity when the CTV did not overlap the RW versus when the CTV overlapped the RW (odds ratio [OR], 0.43; 95% confidence interval [CI], 0.22-0.85; P = .014), and a higher rate of grade ≥2 late genitourinary (GU) toxicity when the CTV overlapped the RW (OR, 2.58; 95% CI, 1.17-5.72; P = .019). A marginally significant lower risk of grade ≥2 late GU toxicity was observed when the prostate bed did not overlap versus did overlap the RW (OR, 0.51; 95% CI, 0.25-1.03; P = .06). In addition, a marginally significant decrease in FFBP was observed in patients with PTV not including surgical clips as potential markers of the limits of the prostate bed (hazard ratio, 1.44; 95% CI, 0.96-2.17; P = .07). CONCLUSIONS: Despite a thorough QA program, the central review of a phase 3 trial showed limited adherence to treatment protocol recommendations, which was associated with a higher risk of toxicity by means of acute or late gastrointestinal or GU toxicity and showed a trend toward worse FFBP. Data from this QA review might help to refine future QA programs and prostate bed delineation guidelines.