Induction therapy with ipilimumab and nivolumab followed by consolidative chemoradiation as organ-sparing treatment in urothelial bladder cancer: study protocol of the INDIBLADE trial.

Introduction: Studies that assessed the efficacy of pre-operative immune checkpoint blockade (ICB) in locally advanced urothelial cancer of the bladder showed encouraging pathological complete response rates, suggesting that a bladder-sparing approach may be a viable option in a subset of patients. Chemoradiation is an alternative for radical cystectomy with similar oncological outcomes, but is still mainly used in selected patients with organ-confined tumors or patients ineligible to undergo radical cystectomy. We propose to sequentially administer ICB and chemoradiation to patients with (locally advanced) muscle-invasive bladder cancer. Methods: The INDIBLADE trial is an investigator-initiated, single-arm, multicenter phase 2 trial. Fifty patients with cT2-4aN0-2M0 urothelial bladder cancer will be treated with ipilimumab 3 mg/kg on day 1, ipilimumab 3 mg/kg plus nivolumab 1 mg/kg on day 22, and nivolumab 3 mg/kg on day 43 followed by chemoradiation. The primary endpoint is the bladder-intact event-free survival (BI-EFS). Events include: local or distant recurrence, salvage cystectomy, death and switch to platinum-based chemotherapy. We will also evaluate the potential of multiparametric magnetic resonance imaging of the bladder to identify non-responders, and we will assess the clearance of circulating tumor DNA as a biomarker for ICB treatment response. Discussion: This is the first trial in which the efficacy of induction combination ICB followed by chemoradiation is being evaluated to provide bladder-preservation in patients with (locally advanced) urothelial bladder cancer. Clinical Trial Registration: The INDIBLADE trial was registered on clinicaltrials.gov on January 21, 2022 (NCT05200988).

Acute and long-term toxicity in patients undergoing induction chemotherapy followed by thermoradiotherapy for advanced cervical cancer.

OBJECTIVES: To determine rates of vascular toxicity, acute kidney injury (AKI), chronic kidney disease (CKD) and survival in high-risk cervical cancer patients treated with platinum-based induction chemotherapy followed by thermoradiotherapy. METHODS: Between January 1999 and April 2017, patients with large primary tumors (>6cm) and/or para-aortic lymph node (LN) metastases >1 cm and/or para-iliac LN >2 cm were included. Patient and tumor characteristics, Common Toxicity Criteria v4.03 scores, laboratory tests and treatment data were retrieved from patient records. CT scans were reviewed for the presence of thrombo-embolic events (TEE). The study protocol was approved by the Medical Ethics Review Committee of Erasmus MC, Rotterdam (MEC2017-133). RESULTS: The 105 included patients had a mean age of 47.9 years (range 22-79) and a median follow-up time of 43 months (IQR 14-72). Median tumor size was 6.0 cm (range 2.6-11.5), 30% had a clinical FIGO stage ≥ IIIB and 42% had enlarged para-aortic LN. Cisplatin-based therapy was started in 86 patients (82%), of whom 30 (35%) switched to carboplatin and 47% of patients completed six cycles of platinum-based chemotherapy. All patients received external beam radiotherapy as planned, 98 patients (93%) underwent brachytherapy as planned or received an external boost, and 95 patients (90%) completed all five planned hyperthermia treatments. During cisplatin chemotherapy, 34 patients experienced AKI (39%). At last follow-up, 35% of patients had chronic renal toxicity (GFR 59 - 15/min/1.73 m2). At presentation, a TEE was present in 10 (10%) and another 23 (22%) patients experienced a TEE (18% venous, 4% arterial) during chemotherapy. Five-year overall survival was 58% (95% CI 47.8-68.6 SE 0.053). CONCLUSION: Achieving a five-year overall survival of 58%, platinum-based induction chemotherapy followed by thermoradiotherapy is an effective treatment for advanced-stage high-risk cervical cancer. However, treatment is accompanied by an unacceptably high prevalence of chemotherapy-associated TEE and acute kidney injury, as well as chronic kidney disease. Future studies should investigate the role of carboplatin in reducing toxicity and the effect of thromboprophylaxis in high-risk patients.

A moderate thermal dose is sufficient for effective free and TSL based thermochemotherapy.

Hyperthermia, i.e. heating the tumor to a temperature of 40-43 °C is considered by many a valuable treatment to sensitize tumor cells to radiotherapy and chemotherapy. In recent randomized trials the great potential of adding hyperthermia to chemotherapy was demonstrated for treatment of high risk soft tissue sarcoma: +11.4% 5 yrs. overall survival (OS) and for ovarian cancer with peritoneal involvement nearly +12 months OS gain. As a result interest in combining chemotherapy with hyperthermia, i.e. thermochemotherapy, is growing. Extensive biological research has revealed that hyperthermia causes multiple effects, from direct cell kill to improved oxygenation, whereby each effect has a specific temperature range. Thermal sensitization of the tumor cell for chemotherapy occurs for many drugs at temperatures ranging from 40 to 42 °C with little additional increase of sensitization at higher temperatures. Increasing perfusion/oxygenation and increased extravasation are two other important hyperthermia induced mechanisms. The combination of free drug and hyperthermia has not been found to increase tumor drug concentration. Hence, enhanced effectiveness of free drug will depend on the thermal sensitization of the tumor cells for the applied drug. In contrast to free drugs, experimental animal studies combining hyperthermia and thermo-sensitive liposomal (TSL) drugs delivery have demonstrated to result in a substantial increase of the drug concentration in the tumor. For TSL based chemotherapy, hyperthermia is critical to both increase perfusion and extravasation as well as to trigger TSL drug release, whereby the temperature controlled induction of a local high drug concentration in a highly permeable vessel is driving the enhanced drug uptake in the tumor. Increased drug concentrations up to 26 times have been reported in rodents. Good control of the tissue temperature is required to keep temperatures below 43 °C to prevent vascular stasis. Further, careful timing of the drug application relative to the start of heating is required to benefit optimal from the combined treatment. From the available experimental data it follows that irrespective whether chemotherapy is applied as free drug or using a thermal sensitive liposomal carrier, the optimal thermal dose for thermochemotherapy should be 40-42 °C for 30-60 min, i.e. equivalent to a CEM43 of 1-15 min. Timing is critical: most free drug should be applied simultaneous with heating, whereas TSL drugs should be applied 20-30 min after the start of hyperthermia.

The Effect of the Time Interval Between Radiation and Hyperthermia on Clinical Outcome in 400 Locally Advanced Cervical Carcinoma Patients.

Background: Addition of deep hyperthermia to radiotherapy results in improved local control (LC) and overall survival compared to radiotherapy alone in cervical carcinoma patients. Based on preclinical data, the time interval between radiotherapy, and hyperthermia is expected to influence treatment outcome. Clinical studies addressing the effect of time interval are sparse. The repercussions for clinical applications are substantial, as the time between radiotherapy and hyperthermia should be kept as short as possible. In this study, we therefore investigated the effect of the time interval between radiotherapy and hyperthermia on treatment outcome. Methods: We analyzed all primary cervical carcinoma patients treated between 1996 and 2016 with thermoradiotherapy at our institute. Data on patients, tumors and treatments were collected, including the thermal dose parameters TRISE and CEM43T90. Follow-up data on tumor status and survival as well as late toxicity were collected. Data was analyzed using Cox proportional hazards analysis and Kaplan Meier analysis. Results: 400 patients were included. Kaplan Meier and univariate Cox analysis showed no effect of the time interval (range 30-230 min) on any clinical outcome measure. Besides known prognostic factors, thermal dose parameters TRISE and CEM43T90 had a significant effect on LC. In multivariate analysis, the thermal dose parameter TRISE (HR 0.649; 95% CI 0.501-0.840) and the use of image guided brachytherapy (HR 0.432; 95% CI 0.214-0.972), but not the time interval, were significant predictors of LC and disease specific survival. Conclusions: The time interval between radiotherapy and hyperthermia, up to 4 h, has no effect on clinical outcome. These results are re-ensuring for our current practice of delivering hyperthermia within maximal 4 h after radiotherapy.

Deep hyperthermia with the HYPERcollar system combined with irradiation for advanced head and neck carcinoma - a feasibility study.

PURPOSE: Radiotherapy (RT) treatment of locally-advanced and recurrent head and neck carcinoma (HNC) results in disappointing outcomes. Combination of RT with cisplatin or cetuximab improves survival but the increased toxicity and patient's comorbidity warrant the need for a less-toxic radiosensitizer. Stimulated by several randomized studies demonstrating the radio-sensitizing effect of hyperthermia, we developed the HYPERcollar. Here, we report early experience and toxicity in patients with advanced HNC. METHODS AND MATERIALS: 119 hyperthermia treatments given to 27 patients were analyzed. Hyperthermia was applied once a week by the HYPERcollar aimed at achieving 39-43 °C in the target area, up to patients' tolerance. Pre-treatment planning was used to optimize treatment settings. When possible, invasive thermometry catheters were placed. RESULTS: Mean power applied during the 119 hyperthermia treatments ranged from 120 to 1007 W (median 543 W). 15 (13%) hyperthermia treatments were not fully completed due to: pain allocated to hyperthermia (6/15), dyspnea from sticky saliva associated with irradiation (2/15) and unknown reasons (7/15). No severe complications or enhanced thermal or mucosal toxicities were observed. Excluding post-operative treatment, response rates after 3 months were 46% (complete) and 7% (partial). CONCLUSION: Hyperthermia with the HYPERcollar proved to be safe and feasible with good compliance and promising outcome.

Association of acute adverse effects with high local SAR induced in the brain from prolonged RF head and neck hyperthermia.

To provide an adequate level of protection for humans from exposure to radio-frequency (RF) electromagnetic fields (EMF) and to assure that any adverse health effects are avoided. The basic restrictions in terms of the specific energy absorption rate (SAR) were prescribed by IEEE and ICNIRP. An example of a therapeutic application of non-ionizing EMF is hyperthermia (HT), in which intense RF energy is focused at a target region. Deep HT in the head and neck (H&N) region involves inducing energy at 434 MHz for 60 min on target. Still, stray exposure of the brain is considerable, but to date only very limited side-effects were observed. The objective of this study is to investigate the stringency of the current basic restrictions by relating the induced EM dose in the brain of patients treated with deep head and neck (H&N) HT to the scored acute health effects. We performed a simulation study to calculate the induced peak 10 g spatial-averaged SAR (psSAR10g) in the brains of 16 selected H&N patients who received the highest SAR exposure in the brain, i.e. who had the minimum brain-target distance and received high forwarded power during treatment. The results show that the maximum induced SAR in the brain of the patients can exceed the current basic restrictions (IEEE and ICNIRP) on psSAR10g for occupational environments by 14 times. Even considering the high local SAR in the brain, evaluation of acute effects by the common toxicity criteria (CTC) scores revealed no indication of a serious acute neurological effect. In addition, this study provides pioneering quantitative human data on the association between maximum brain SAR level and acute adverse effects when brains are exposed to prolonged RF EMF.

Distant metastasis in patients with cervical cancer after primary radiotherapy with or without chemotherapy and image guided adaptive brachytherapy.

OBJECTIVE: The aim of this study is to investigate patterns of distant relapse after primary radiochemotherapy in cervical cancer patients. METHODS: All patients with cervical cancer treated in curative intent with external beam radiotherapy +/- chemotherapy and image-guided adaptive brachytherapy between January 1998 and June 2009 at the Medical University of Vienna were included in this retrospective analysis. Patients with locoregional recurrences were excluded from this study. Presence, site of and time to distant metastases were recorded. For identifying prognostic factors, uni- and multivariate analyses using Cox regression analysis were performed. Based on the result from the multivariate analysis, patients were stratified into a high and a low risk group. The Kaplan-Meier method was used to estimate distant-metastasis-free-survival in the overall cohort, in the risk groups and for analysing the impact of chemotherapy within the risk groups. RESULTS: A total number of 189 patients were included in this study. After a median follow-up of 54 months, 49 patients developed distant metastases. Overall, distant-metastasis-free-survival 5 years after treatment was 73%. FIGO stage, lymph node status and the extent of tumour regression during treatment were significant predictors for distant metastasis. Distant-metastasis-free-survival 5 years after treatment was 91% and 60% in the low and high risk groups, respectively. The number of the cycles of chemotherapy had a significant impact on the occurrence of distant metastasis in high risk patients, but not in low risk patients. CONCLUSION: Patients with high risk factors have a 40% probability of developing distant metastasis within 5 years. In these patients, decreasing the number of cycles of cisplatin may increase their probability of developing distant metastasis.

Benefit of replacing the Sigma-60 by the Sigma-Eye applicator. A Monte Carlo-based uncertainty analysis.

BACKGROUND AND PURPOSE: To investigate the clinical benefit of replacing the BSD-2000 Sigma-60 with the Sigma-Eye applicator, taking into account effects of uncertainties in tissue and water bolus parameters. PATIENTS AND METHODS: For 20 patients, specific absorption rate (SAR) and temperature distributions were calculated and optimized, based on computed tomography (CT) scans in treatment position. The impact of uncertainties on predicted distributions was studied using a Monte Carlo uncertainty assessment. RESULTS: Replacing the Sigma-60 by the Sigma-Eye applicator resulted in a higher SAR in the tumor [on average a decrease of the hotspot tumor quotient (HTQ) by 24%; p < 0.001], and higher temperatures (T90: +0.4°C, p < 0.001; T50: +0.6°C, p < 0.001) using literature values and SAR optimization. When temperature optimization (T90) was used, a larger average increase was found (T90: +0.7°C, p < 0.001; T50: +0.8°C, p < 0.001). When taking into account uncertainties, a decrease of 23% in median HTQ (p < 0.001) and an increase in T50 and T90 of 0.4°C (p < 0.001) could be demonstrated. CONCLUSION: Based on this uncertainty analysis, significant and clinically relevant improvements in HTQ and tumor temperature were achieved when replacing the Sigma-60 by the Sigma-Eye applicator.

Optimizing deep hyperthermia treatments: are locations of patient pain complaints correlated with modelled SAR peak locations?

During deep hyperthermia treatment, patient pain complaints due to heating are common when maximizing power. Hence, there exists a good rationale to investigate whether the locations of predicted SAR peaks by hyperthermia treatment planning (HTP) are correlated with the locations of patient pain during treatment. A retrospective analysis was performed, using the treatment reports of 35 patients treated with deep hyperthermia controlled by extensive treatment planning. For various SAR indicators, the average distance from a SAR peak to a patient discomfort location was calculated, for each complaint. The investigated V(0.1 closest) (i.e. the part of the 0.1th SAR percentile closest to the patient complaint) performed the best, and leads to an average distance between the SAR peak and the complaint location of 3.9 cm. Other SAR indicators produced average distances that were all above 10 cm. Further, the predicted SAR peak location with V(0.1) provides a 77% match with the region of complaint. The current study demonstrates that HTP is able to provide a global indication of the regions where hotspots during treatment will most likely occur. Further development of this technology is necessary in order to use HTP as a valuable toll for objective and advanced SAR steering. The latter is especially valid for applications that enable 3D SAR steering.

Patient positioning in deep hyperthermia: influences of inaccuracies, signal correction possibilities and optimization potential.

In this deep hyperthermia study, the robustness of SAR (specific absorption rate) patterns to patient-position variations is assessed, as well as the possibilities to correct for improper positioning and the benefits of non-standard positions. With a finite element model, the SAR distributions were predicted for ten patients at 33 positions. Position sensitivity is assessed for both SAR-focus steering, i.e. settings based on a calculated focus in a cylindrical patient representation, and HTP (hyperthermia treatment planning)-guided steering, i.e. model-based optimization of the SAR distribution. Position inaccuracies of less than 1 cm do not significantly affect SAR patterns. For SAR-focus steering, the SAR maximum is not always at the desired focus location, especially in the Y (anterior/posterior)- and Z (axial)-directions. For a maximum shift of 5 cm in all directions, both SAR-focus steering and HTP-guided steering are suitable to correct for improper positioning up to the level that none of the investigated positions appears preferable. Current positioning precision is sufficient in the X (right-left)-direction, but precision measurements are needed to reach the desired accuracy in the Y-direction. In the Z-direction, a cranial shift of the applicator is predicted to be beneficial. If the position is known accurately, correction of the treatment setting is possible without loss of heating efficiency. Additionally, no preferable positions exist.

Complaint-adaptive power density optimization as a tool for HTP-guided steering in deep hyperthermia treatment of pelvic tumors.

For an efficient clinical use of HTP (hyperthermia treatment planning), optimization methods are needed. In this study, a complaint-adaptive PD (power density) optimization as a tool for HTP-guided steering in deep hyperthermia of pelvic tumors is developed and tested. PD distribution in patients is predicted using FE-models. Two goal functions, Opt1 and Opt2, are applied to optimize PD distributions. Optimization consists of three steps: initial optimization, adaptive optimization after a first complaint and increasing the weight of a region after recurring complaints. Opt1 initially considers only target PD whereas Opt2 also takes into account hot spots. After patient complaints though, both limit PD in a region. Opt1 and Opt2 are evaluated in a phantom test, using patient models and during hyperthermia treatment. The phantom test and a sensitivity study in ten patient models, show that HTP-guided steering is most effective in peripheral complaint regions. Clinical evaluation in two groups of five patients shows that time between complaints is longer using Opt2 (p = 0.007). However, this does not lead to significantly different temperatures (T50s of 40.3 (Opt1) versus 40.1 degrees C (Opt2) (p = 0.898)). HTP-guided steering is feasible in terms of PD reduction in complaint regions and in time consumption. Opt2 is preferable in future use, because of better complaint reduction and control.

Ankle brachial index measurements in critical leg ischaemia--the influence of experience on reproducibility.

BACKGROUND AND AIMS: While the use of ankle brachial indices (ABI) in the screening for peripheral arterial obstructive disease is widely accepted, the applicability of ABI in the identification of critical leg ischaemia (CLI) is far from settled. The aim was to assess inter-observer variability of ABI measurements in patients with CLI. MATERIAL AND METHODS: The study was conducted in two parts. In both parts a hand-held 9.5 MHz Doppler device was used. PART A: ABI was measured by 7 measurers with variable measurement experience in 22 limbs of patients admitted to the surgical ward because of CLI. The agreement between the measurements was assessed. PART B: Inter-observer agreement in measuring ABI was assessed between 2 trained vascular technicians measuring 33 limbs in patients with CLI on the vascular outpatient clinic. RESULTS AND CONCLUSIONS: Part A: 16% of the ABI-values differed 0.15 or more from the median and the mean coefficient of variation was 56.1. Part B: The difference between measurements did not exceed 0.14 with a mean coefficient of variation of 3.2. To obtain reproducible and quantitative measurement values the measurements have to be performed by trained personnel. Measurements performed by untrained personnel can only be regarded as qualitative.