Ifosfamide plus etoposide combined with regional hyperthermia in patients with locally advanced sarcomas: a phase II study

Evaluation of thermal dose effect in radiofrequency-induced hyperthermia with intravesical chemotherapy for nonmuscle invasive bladder cancer

PURPOSE

In nonmuscle invasive bladder cancer (NMIBC) patients who fail standard intravesical treatment and are unfit or unwilling to undergo a radical cystectomy, radiofrequency (RF)-induced hyperthermia combined with intravesical chemotherapy (RF-CHT) has shown promising results. We studied whether higher thermal dose improves clinical NMIBC outcome.

METHODS AND MATERIALS

The cohort comprised 108 patients who started with RF-CHT between November 2013 and December 2019. Patients received intravesical mitomycin-C or epirubicin. Bladder hyperthermia was accomplished with an intravesical 915 MHz RF device guided by intravesical thermometry. We assessed the association between thermal dose parameters (including median temperature and Cumulative Equivalent Minutes of T50 at 43 °C [CEM43T50]) and complete response (CR) at six months for patients with (concomitant) carcinoma in situ (CIS), and recurrence-free survival (RFS) for patients with papillary disease.

RESULTS

Median temperature and CEM43T50 per treatment were 40.9 (IQR 40.8-41.1) °C and 3.1 (IQR 0.9-2.4) minutes, respectively. Analyses showed no association between any thermal dose parameter and CR or RFS (p > 0.05). Less bladder spasms during treatment sessions was associated with increased median temperature and CEM43T50 (adjusted OR 0.01 and 0.34, both p < 0.001).

CONCLUSIONS

No significant association between thermal dose and NMIBC outcome was found. Possibly thermal dose effect in patients of the current cohort exceeds a certain threshold value. On the other hand, occurrence of bladder spasms had a thermal dose limiting effect. We advise to treat patients with temperatures >40.5 °C for at least 45 min while respecting individual tolerability, including occurrence of bladder spasms.

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.

Preoperative hypofractionated radiotherapy for soft tissue sarcomas: a systematic review

Background

Soft tissue sarcomas (STS) represent a diverse group of rare malignant tumors. Currently, five to six weeks of preoperative radiotherapy (RT) combined with surgery constitute the mainstay of therapy for localized high-grade sarcomas (G2–G3). Growing evidence suggests that shortening preoperative RT courses by hypofractionation neither increases toxicity rates nor impairs oncological outcomes. Instead, shortening RT courses may improve therapy adherence, raise cost-effectiveness, and provide more treatment opportunities for a wider range of patients. Presumed higher rates of adverse effects and worse outcomes are concerns about hypofractionated RT (HFRT) for STS. This systematic review summarizes the current evidence on preoperative HFRT for the treatment of STS and discusses toxicity and oncological outcomes compared to normofractionated RT.

Methods

We conducted a systematic review of clinical trials describing outcomes for preoperative HFRT in the management of STS using PubMed, the Cochrane library, the Cochrane Central Register of Controlled Trials, ClinicalTrials.gov, Embase, and Ovid Medline. We followed the 2020 Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Trials on retroperitoneal sarcomas, postoperative RT, and hyperthermia were excluded. Articles published until November 30th, 2021, were included.

Results

Initial search yielded 94 articles. After removal of duplicate and ineligible articles, 13 articles qualified for analysis. Eight phase II trials and five retrospective analyses were reviewed. Most trials applied 5 × 5 Gy preoperatively in patients with high-grade STS. HFRT courses did not show increased rates of adverse events compared to historical trials of normofractionated RT. Toxicity rates were mostly comparable or lower than in trials of normofractionated RT. Moreover, HFRT achieved comparable local control rates with shorter duration of therapy. Currently, more than 15 prospective studies on HFRT + / − chemotherapy are ongoing.

Conclusions

Retrospective data and phase II trials suggest preoperative HFRT to be a reasonable treatment modality for STS. Oncological outcomes and toxicity profiles were favorable. To date, our knowledge is mostly derived from phase II data. No randomized phase III trial comparing normofractionated and HFRT in STS has been published yet. Multiple ongoing phase II trials applying HFRT to investigate acute and late toxicity will hopefully bring forth valuable findings.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13014-022-02072-9.

Systematic review of pre-clinical and clinical devices for magnetic resonance-guided radiofrequency hyperthermia

Clinical trials have demonstrated the therapeutic benefits of adding radiofrequency (RF) hyperthermia (HT) as an adjuvant to radio- and chemotherapy. However, maximum utilization of these benefits is hampered by the current inability to maintain the temperature within the desired range. RF HT treatment quality is usually monitored by invasive temperature sensors, which provide limited data sampling and are prone to infection risks. Magnetic resonance (MR) temperature imaging has been developed to overcome these hurdles by allowing noninvasive 3D temperature monitoring in the target and normal tissues. To exploit this feature, several approaches for inserting the RF heating devices into the MR scanner have been proposed over the years. In this review, we summarize the status quo in MR-guided RF HT devices and analyze trends in these hybrid hardware configurations. In addition, we discuss the various approaches, extract best practices and identify gaps regarding the experimental validation procedures for MR - RF HT, aimed at converging to a common standard in this process.

Quo Vadis Oncological Hyperthermia (2020)?

Heating as a medical intervention in cancer treatment is an ancient approach, but effective deep heating techniques are lacking in modern practice. The use of electromagnetic interactions has enabled the development of more reliable local-regional hyperthermia (LRHT) techniques whole-body hyperthermia (WBH) techniques. Contrary to the relatively simple physical-physiological concepts behind hyperthermia, its development was not steady, and it has gone through periods of failures and renewals with mixed views on the benefits of heating seen in the medical community over the decades. In this review we study in detail the various techniques currently available and describe challenges and trends of oncological hyperthermia from a new perspective. Our aim is to describe what we believe to be a new and effective approach to oncologic hyperthermia, and a change in the paradigm of dosing. Physiological limits restrict the application of WBH which has moved toward the mild temperature range, targeting immune support. LRHT does not have a temperature limit in the tumor (which can be burned out in extreme conditions) but a trend has started toward milder temperatures with immune-oriented goals, developing toward immune modulation, and especially toward tumor-specific immune reactions by which LRHT seeks to target the malignancy systemically. The emerging research of bystander and abscopal effects, in both laboratory investigations and clinical applications, has been intensified. Our present review summarizes the methods and results, and discusses the trends of hyperthermia in oncology.

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.

Effect of Neoadjuvant Chemotherapy Plus Regional Hyperthermia on Long-term Outcomes Among Patients With Localized High-Risk Soft Tissue Sarcoma: The EORTC 62961-ESHO 95 Randomized Clinical Trial

Importance

Patients with soft tissue sarcoma are at risk for local recurrence and distant metastases despite optimal local treatment. Preoperative anthracycline plus ifosfamide chemotherapy improves outcome in common histological subtypes.

Objective

To analyze whether the previously reported improvement in local progression-free survival by adding regional hyperthermia to neoadjuvant chemotherapy translates into improved survival.

Design, Setting, and Participants

Open-label, phase 3 randomized clinical trial to evaluate the efficacy and toxic effects of neoadjuvant chemotherapy plus regional hyperthermia. Adult patients (age ≥18 years) with localized soft tissue sarcoma (tumor ≥5 cm, French Federation Nationale des Centers de Lutte Contre le Cancer [FNCLCC] grade 2 or 3, deep) were accrued across 9 centers (6, Germany; 1, Norway; 1, Austria; 1, United States) from July 1997 to November 2006. Follow-up ended December 2014.

Interventions

After stratification for tumor presentation and site, patients were randomly assigned to either neoadjuvant chemotherapy consisting of doxorubicin, ifosfamide, and etoposide alone, or combined with regional hyperthermia.

Main Outcomes and Measures

The primary end point was local progression-free survival. Secondary end points included treatment safety and survival, with survival defined from date of randomization to death due to disease or treatment. Patients lost to follow-up were censored at the date of their last follow-up.

Results

A total of 341 patients were randomized, and 329 (median [range] age, 51 [18-70] years; 147 women, 182 men) were eligible for the intention-to-treat analysis. By December 2014, 220 patients (67%; 95% CI, 62%-72%) had experienced disease relapse, and 188 (57%; 95% CI, 52%-62%) had died. Median follow-up was 11.3 years. Compared with neoadjuvant chemotherapy alone, adding regional hyperthermia improved local progression-free survival (hazard ratio [HR], 0.65; 95% CI, 0.49-0.86; P = .002). Patients randomized to chemotherapy plus hyperthermia had prolonged survival rates compared with those randomized to neoadjuvant chemotherapy alone (HR, 0.73; 95% CI, 0.54-0.98; P = .04) with 5-year survival of 62.7% (95% CI, 55.2%-70.1%) vs 51.3% (95% CI, 43.7%-59.0%), respectively, and 10-year survival of 52.6% (95% CI, 44.7%-60.6%) vs 42.7% (95% CI, 35.0%-50.4%).

Conclusions and Relevance

Among patients with localized high-risk soft tissue sarcoma the addition of regional hyperthermia to neoadjuvant chemotherapy resulted in increased survival, as well as local progression-free survival. For patients who are candidates for neoadjuvant treatment, adding regional hyperthermia may be warranted.

Trial Registration

clinicaltrials.gov Identifier: NCT00003052.

A phase II trial of Ifosfamide combination with recommended supportive therapy for recurrent SCLC in second-line and heavily treated setting

PURPOSE

The response rate of ifosfamide (IFM) monotherapy for small-cell lung cancer (SCLC) is reported as 42.4% in Japanese package insert. However, these efficacy data are based on clinical studies conducted in 1970s. This phase II study evaluated the efficacy and safety of IFM combination with recommended current supportive therapy for recurrent SCLC in second-line and heavily treated setting.

METHODS

Recurrent SCLC patients pretreated with one to three prior regimens received IFM monotherapy (1.5 g/m² for 3 days every 3 weeks). Treatment was continued until disease progression or unacceptable toxicity. The primary end point was objective response rate.

RESULTS

Twelve patients were enrolled in the study from June 2009 to January 2013. The study was early terminated at interim analysis due to futility stop. Patient characteristics were as follows: median age was 65 years, 11 were males (91.7%) and eight (66.7%) and four (33.3%) were Performance Status 0 and 1, respectively. Four patients (33.3%) enrolled in second-line setting were all refractory relapse SCLC and 8 (66.7%) were heavily treated patients. No patient showed objective response. Stable disease was observed in 3 patients. Median progression-free survival and overall survival were 0.9 months (95% CI, 0.3-1.5) and 4.8 months (95% CI, 1.6-9.9), respectively. Although one grade 4 amylase increase possibly related to IFM was observed, toxicity profile was totally favorable.

CONCLUSIONS

IFM monotherapy should not be used for refractory relapse or heavily treated SCLC, and no further investigation is required in these populations.

Quality assurance guidelines for superficial hyperthermia clinical trials: I. Clinical requirements

Quality assurance guidelines are essential to provide uniform execution of clinical trials and treatment in the application of hyperthermia. This document provides definitions for a good hyperthermia treatment and identifies the clinical conditions where a certain hyperthermia system can or cannot adequately heat the tumour volume. It also provides brief description of the characteristics and performance of the current electromagnetic (radiative and capacitive), ultrasound and infra-red heating techniques. This information helps to select the appropriate heating technique for the specific tumour location and size, and appropriate settings of the water bolus and thermometry. Finally, requirements of staff training and documentation are provided. The guidelines in this document focus on the clinical application and are complemented with a second, more technical quality assurance document providing instructions and procedure to determine essential parameters that describe heating properties of the applicator for superficial hyperthermia. Both sets of guidelines were developed by the ESHO Technical Committee with participation of senior STM members and members of the Atzelsberg Circle.

Hyperthermia adds to trabectedin effectiveness and thermal enhancement is associated with BRCA2 degradation and impairment of DNA homologous recombination repair

The tetrahydroisoquinoline trabectedin is a marine compound with approved activity against human soft-tissue sarcoma. It exerts antiproliferative activity mainly by specific binding to the DNA and inducing DNA double-strand breaks (DSB). As homologous recombination repair (HRR)-deficient tumors are more susceptible to trabectedin, hyperthermia-mediated on-demand induction of HRR deficiency represents a novel and promising strategy to boost trabectedin treatment. For the first time, we demonstrate enhancement of trabectedin effectiveness in human sarcoma cell lines by heat and characterize cellular events and molecular mechanisms related to heat-induced effects. Hyperthermic temperatures (41.8 or 43°C) enhanced significantly trabectedin-related clonogenic cell death and G2/M cell cycle arrest followed by cell type-dependent induction of apoptosis or senescence. Heat combination increased accumulation of γH2AX foci as key marker of DSBs. Expression of BRCA2 protein, an integral protein of the HRR machinery, was significantly decreased by heat. Consequently, recruitment of downstream RAD51 to γH2AX-positive repair foci was almost abolished indicating relevant impairment of HRR by heat. Accordingly, enhancement of trabectedin effectiveness was significantly augmented in BRCA2-proficient cells by hyperthermia and alleviated in BRCA2 knockout or siRNA-transfected BRCA2 knockdown cells. In peripheral blood mononuclear cells isolated from sarcoma patients, increased numbers of nuclear γH2AX foci were detected after systemic treatment with trabectedin and hyperthermia of the tumor region. The findings establish BRCA2 degradation by heat as a key factor for a novel treatment strategy that allows targeted chemosensitization to trabectedin and other DNA damaging antitumor drugs by on-demand induction of HRR deficiency.

Thermoresponsive fluorinated small-molecule drugs: a new concept for efficient localized chemotherapy

We review the drugs used in combination with hyperthermia for cancer therapy and recent advances on small thermoresponsive molecules.

Multidisciplinary management of soft tissue sarcomas

Musculoskeletal sarcomas are a heterogeneous group of malignant neoplasms derived from connective tissue. Sarcomas represent about 1% of cancer in adults. The annual incidence in adults in Europe is around 14,000 new cases of soft tissue sarcomas (STS) and 4,800 new cases of bone sarcomas. Musculoskeletal tumours arise anywhere in the body, although lower extremities are the most common site of appearance, followed by upper extremities, trunk, retroperitoneum and head and neck area. Adequate management of STS is a stimulating challenge for oncologists. The aim of treatment should be focused on four main aspects: improving survival, avoiding local recurrence, maximising organ function and, finally, minimising morbidity. Surgery, radiotherapy and, sometimes though increasingly, chemotherapy are the pillars on which rests the modern treatment of sarcomas. The optimal management of musculoskeletal tumour requires a multidisciplinary integration of these different approaches in treatment planning right from the initial diagnoses. Referring patients to qualified centres should be desirable to achieve the maximum probability of control and even cure for STS.

Neo-adjuvant chemotherapy alone or with regional hyperthermia for localised high-risk soft-tissue sarcoma: a randomised phase 3 multicentre study

BACKGROUND

The optimum treatment for high-risk soft-tissue sarcoma (STS) in adults is unclear. Regional hyperthermia concentrates the action of chemotherapy within the heated tumour region. Phase 2 studies have shown that chemotherapy with regional hyperthermia improves local control compared with chemotherapy alone. We designed a parallel-group randomised controlled trial to assess the safety and efficacy of regional hyperthermia with chemotherapy.

METHODS

Patients were recruited to the trial between July 21, 1997, and November 30, 2006, at nine centres in Europe and North America. Patients with localised high-risk STS (> or = 5 cm, Fédération Nationale des Centres de Lutte Contre le Cancer [FNCLCC] grade 2 or 3, deep to the fascia) were randomly assigned to receive either neo-adjuvant chemotherapy consisting of etoposide, ifosfamide, and doxorubicin (EIA) alone, or combined with regional hyperthermia (EIA plus regional hyperthermia) in addition to local therapy. Local progression-free survival (LPFS) was the primary endpoint. Efficacy analyses were done by intention to treat. This trial is registered with ClinicalTrials.gov, number NCT 00003052.

FINDINGS

341 patients were enrolled, with 169 randomly assigned to EIA plus regional hyperthermia and 172 to EIA alone. All patients were included in the analysis of the primary endpoint, and 332 patients who received at least one cycle of chemotherapy were included in the safety analysis. After a median follow-up of 34 months (IQR 20-67), 132 patients had local progression (56 EIA plus regional hyperthermia vs 76 EIA). Patients were more likely to experience local progression or death in the EIA-alone group compared with the EIA plus regional hyperthermia group (relative hazard [RH] 0.58, 95% CI 0.41-0.83; p=0.003), with an absolute difference in LPFS at 2 years of 15% (95% CI 6-26; 76% EIA plus regional hyperthermia vs 61% EIA). For disease-free survival the relative hazard was 0.70 (95% CI 0.54-0.92, p=0.011) for EIA plus regional hyperthermia compared with EIA alone. The treatment response rate in the group that received regional hyperthermia was 28.8%, compared with 12.7% in the group who received chemotherapy alone (p=0.002). In a pre-specified per-protocol analysis of patients who completed EIA plus regional hyperthermia induction therapy compared with those who completed EIA alone, overall survival was better in the combined therapy group (HR 0.66, 95% CI 0.45-0.98, p=0.038). Leucopenia (grade 3 or 4) was more frequent in the EIA plus regional hyperthermia group compared with the EIA-alone group (128 of 165 vs 106 of 167, p=0.005). Hyperthermia-related adverse events were pain, bolus pressure, and skin burn, which were mild to moderate in 66 (40.5%), 43 (26.4%), and 29 patients (17.8%), and severe in seven (4.3%), eight (4.9%), and one patient (0.6%), respectively. Two deaths were attributable to treatment in the combined treatment group, and one death was attributable to treatment in the EIA-alone group.

INTERPRETATION

To our knowledge, this is the first randomised phase 3 trial to show that regional hyperthermia increases the benefit of chemotherapy. Adding regional hyperthermia to chemotherapy is a new effective treatment strategy for patients with high-risk STS, including STS with an abdominal or retroperitoneal location.

FUNDING

Deutsche Krebshilfe, Helmholtz Association (HGF), European Organisation of Research and Treatment of Cancer (EORTC), European Society for Hyperthermic Oncology (ESHO), and US National Institute of Health (NIH).

Effects of hyperthermia on the peripheral nervous system: a review

The present paper overviews the current knowledge about effects of hyperthermia at temperatures used in clinical oncology on the peripheral nervous system. From the experimental studies it may be concluded that the heat sensitivity of the nerve is determined by the sensitivity of the nerve vasculature. These studies show that in order to avoid induction of severe neuropathy, application of heat to the peripheral nerves should not be in excess of doses of 30 min at 44 degrees C or equivalent. Using modern equipment for application of loco-regional hyperthermia the incidence of even mild neurological complications is very low. In hyperthermic isolated limb perfusion (HILP) neurotoxicity is an often-mentioned side effect, this is in spite of the fact that in all studies a relatively mild hyperthermic temperature is used that, based on the experimental studies, should be well tolerated by the nerves and other normal tissues in the limbs. It seems that the neurotoxicity observed after HILP results from thermal enhancement of drug toxicity, very probably combined with effects of a high tourniquet pressure that is used to isolate the blood flow in the leg. Whole body hyperthermia (WBH), using anesthesia and appropriate monitoring to avoid cardiovascular stress is at present considered a safe procedure. Still in the recent past cases of neuropathy after treatment have been described. When chemotherapy, and notably cisplatin, is administered before or during hyperthermia there are several clinical and experimental observations that indicate a limited tolerance of the peripheral nervous tissue in such case. Also previous radiotherapy may limit the tolerance of nerves to hyperthermia, notably when radiation is applied with a large field size. Experimental studies show that combined treatment with radiation and heat leads to enhancement of effects of radiation (enhancement ratio approximately 1.5 at 60 min at 44 degrees C). A clear contraindication for the application of hyperthermia in patients is the presence of a neurodegenerative disease, such as multiple sclerosis. Vigilance is also required in the treatment of diabetic patients with hyperthermia, this based on experimental animal studies, but so far no clear clinical data are available.

Ifosfamide, carboplatin and etoposide (ICE) as second-line regimen alone and in combination with regional hyperthermia is active in chemo-pre-treated advanced soft tissue sarcoma of adults

PURPOSE

To evaluate the efficacy and safety of the combination of ICE (ifosfamide 1.5 g m(-2), carboplatin 100 mg m(-2) and etoposide 150 mg m(-2), days 1-4, q 28 days, G-CSF 5 microg kg(-1) starting from day 6) alone and in combination with regional hyperthermia (RHT) in soft tissue sarcoma (STS) refractory to previous standard doxorubicin-ifosfamide-based chemotherapy.

PATIENTS AND METHODS

Twenty patients with advanced STS of different histological sub-types were treated with the ICE regimen with 13 patients receiving additional RHT. A median of four courses of ICE were administered with RHT on days 1 and 3 (60 min, T(max) 42 degrees C).

RESULTS

The objective response rate was 20%, with four partial responses (all treated with hyperthermia). In addition, two patients showed mixed responses and five patients stable disease. After a median follow-up time of 15 months, median time to progression was 6 months. Progression free rate estimates were 60% and 45% at 3 and 6 months, respectively. Median overall survival for all patients was 14.6 months.

CONCLUSION

These results suggest that ICE alone or combined with RHT shows activity as second-line therapy in doxorubicin-ifosfamide-refractory STS.

Hyperthermia enhances tumour necrosis factor-related apoptosis-inducing ligand (TRAIL)-induced apoptosis in human cancer cells

PURPOSE

This study investigated whether hyperthermia can enhance TRAIL-induced apoptotic death.

METHODS

Human prostate adenocarcinoma DU-145, human pancreatic carcinoma MIA PaCa-2 and BxPC-3, human colon fibroblast CCD-33Co and rat prostate endothelial YPEN-1 cells were treated with various concentrations of TRAIL (0-200 ngml(-1)) with hyperthermia (40-42 degrees C).

RESULTS

It was observed in human cancer cells, but not in normal cells, that TRAIL induced apoptotic death and also that hyperthermia (40-42 degrees C) promoted TRAIL-induced apoptotic death. Enhancement of TRAIL-mediated apoptosis by hyperthermia was detected by an increase in PARP cleavage, the hallmark feature of apoptosis, as well as by activation of caspases. There were no significant changes in the intra-cellular levels of death receptors (DRs), decoy receptors (DcRs) and anti-apoptotic proteins. Interestingly, data from in vitro enzyme kinetics assay demonstrated that hyperthermia promoted caspase enzyme activity.

CONCLUSIONS

These data suggest that cancer cells are more susceptible to TRAIL in the condition of hyperthermia (40-42 degrees C). The promotion of caspase enzyme activity by hyperthermia may be responsible for enhancement of TRAIL-induced apoptotic death.

Avascular osteonecrosis after hyperthermia in children and adolescents with pelvic malignancies: a retrospective analysis of potential risk factors

PURPOSE

In children with locally advanced or recurrent malignant tumours, prognosis can be improved by regional deep hyperthermia (RHT) in combination with platin-based chemotherapy. However, because of the increasing number of patients that achieve long-time remission with this therapy, it is necessary to evaluate long-term sequelae of thermochemotherapy. During the years 1993-2004 one has observed avascular osteonecrosis (AON) of the femoral head after RHT in seven children with pelvic germ cell tumours or rhabdomyosarcomas.

METHODS

Although AON may develop in patients with malignancies treated with chemo- or radiotherapy alone, RHT might nevertheless contribute to the occurrence of AON. In order to determine potential risk factors for AON after RHT, this study analysed the relationship of AON to the patient's age, medical history and treatment parameters such as thermal dose equivalent and power output.

RESULTS AND CONCLUSIONS

In the present study AON was associated with young age as well as intensity of hyperthermia indicated by high power levels that exceed 20 W per kg body weight and/or application of eight or more heat sessions as well as additional radiotherapy. Based on this observation, it was assumed that an optimized three dimensional thermal field modelling may be helpful to avoid hazardous temperatures in the femoral heads during RHT treatment and to reduce AON of the femoral heads.

High-risk soft tissue sarcoma: clinical trial and hyperthermia combined chemotherapy

For high-risk soft tissue sarcomas (HR-STS) of adults, new treatment strategies are needed to improve outcome with regard to local control and overall survival. Systemic chemotherapy has been integrated either after (adjuvant) or before (neoadjuvant) optimal local treatment by surgery and radiotherapy in HR-STS. This short overview summarizes the results of the combination with regional hyperthermia as a new treatment strategy to open a new therapeutic window.

Thermal monitoring: invasive, minimal-invasive and non-invasive approaches

BACKGROUND

Thermal treatments need verification of effectiveness. Invasive intra-tumoural thermometry was established as a standard method several years ago. However, in deep heating, invasive techniques have disadvantages. Therefore, alternatives have been suggested and are under development.

METHODS

In three phase II studies treating rectal cancer, cervical cancer and prostate cancer, this study replaced invasive (intra-tumoural) thermometry by tumour-related reference points or catheter sections in the rectum, vagina or urethra. Index temperatures and thermal dose parameters were determined. Two recent studies treated patients with recurrent rectal cancer and soft tissue sarcoma using non-invasive MR-thermometry employing the SIGMA-Eye applicator. The proton resonance frequency shift (PRFS) method was employed to generate MR-temperature distributions during the entire heat treatment in 10 min intervals (via phase differences). Fat correction (nulling specified regions in the fat tissue) was utilized to calibrate the method, in particular with respect to the B0-drift.

RESULTS

Statistically significant correlations were found between response (downstaging, WHO) and thermal parameters in rectal cancer (37 patients, rectum measurement, T90, cum min T90 >or= 40.5 degrees C) and cervical cancer (30 patients, vagina, mean temperature and equ min 43 degrees C in a reference point). In prostate cancer (14 patients), a clear correlation was verified between long-term PSA control (<or=1 ng ml-1) and urethral temperatures (T90, Tmax cum min T90 >or= 40.5 degrees C). The mean MR-temperature in the tumour at steady-state as well as the mean T90 were significantly correlated with response for recurrent rectal carcinoma regarding palliation and analgesia (15 patients) and with pathohistological regression rate in soft tissue sarcoma (nine patients).

CONCLUSIONS

For tumours in the pelvis and in the lower extremities, invasive measurements can be replaced by minimally-invasive or non-invasive techniques, which provide equivalent or even more complete information. Extending the application of these surveillance methods to abdominal tumours or liver metastases is a challenge, but strongly desirable for clinical reasons.

The role of hyperthermia in combined treatment in the management of soft tissue sarcoma

For high-risk soft tissue sarcomas (HR-STS) of adults, new treatment strategies are needed to improve outcome with regard to local control and overall survival. Systemic chemotherapy has been integrated either after (adjuvant) or before (neoadjuvant) optimal local treatment by surgery and radiotherapy in HR-STS. This short overview summarizes the results of the combination with regional hyperthermia as a new treatment strategy to open a new therapeutic window.

Noninvasive magnetic resonance thermography of soft tissue sarcomas during regional hyperthermia

BACKGROUND

The objective of this study was to evaluate noninvasive magnetic resonance (MR) thermography for the monitoring of regional hyperthermia (RHT) in patients with soft tissue sarcomas of the lower extremities and pelvis.

METHODS

Noninvasive MR monitoring during RHT was performed in 9 patients who had high-risk soft tissue sarcomas of the lower extremities or pelvis during neoadjuvant chemotherapy plus RHT in the scope of the European Organization for Research and Treatment of Cancer 62961/European Society for Hyperthermic Oncology RHT-95 study. Anatomic and temperature-sensitive data sets were acquired every 10 minutes before and during RHT (using gradient-echo-sequences with variable echo times). MR temperature distributions were derived from the phase differences by using the proton-resonance frequency shift method. A phase convolution setting phase shifts to zero in the fat tissue was performed as a drift correction. The mean MR temperatures in the tumor and muscles and the index temperatures (e.g., T90, which covers 90% of the target volume) and thermal doses were determined and compared with pathohistologic responses and direct temperature measurements if available.

RESULTS

Thirty of 72 MR-thermography data sets (>40% of heat sessions) were evaluable. A significant correlation was observed between pathohistologic response (defined as a necrosis rate >or=90%) and standardized thermal parameters, such as thermal dose cumulative equivalent minutes at 43 degrees C to 90% of the target volume (T90) (P = .050), mean T90 (P = .048), or T50 (P = .050). The correlation of 13 conventional temperature measurements performed in selected patients and sessions invasively in the tumor or noninvasively in rectum and bladder revealed an excellent correlation with MR temperatures (R2 = .96).

CONCLUSIONS

Noninvasive MR thermography of soft tissue sarcoma was feasible and suitable for validating the quality of heating during RHT.

Noninvasive Magnetic Resonance Thermography of Recurrent Rectal Carcinoma in a 1.5 Tesla Hybrid System

To implement noninvasive thermometry, we installed a hybrid system consisting of a radiofrequency multiantenna applicator (SIGMA-Eye) for deep hyperthermia (BSD-2000/3D) integrated into the gantry of a 1.5 Tesla magnetic resonance (MR) tomograph Symphony. This system can record MR data during radiofrequency heating and is suitable for application and evaluation of methods for MR thermography. In 15 patients with preirradiated pelvic rectal recurrences, we acquired phase data sets (25 slices) every 10 to 15 minutes over the treatment time (60-90 minutes) using gradient echo sequences (echo time = 20 ms), transformed the phase differences to MR temperatures, and fused the color-coded MR-temperature distributions with anatomic T1-weighted MR data sets. We could generate one complete series of MR data sets per patient with satisfactory quality for further analysis. In fat, muscle, water bolus, prostate, bladder, and tumor, we delineated regions of interest (ROI), used the fat ROI for drift correction by transforming these regions to a phase shift zero, and evaluated the MR-temperature frequency distributions. Mean MR temperatures (T(MR)), maximum T(MR), full width half maximum (FWHM), and other descriptors of tumors and normal tissues were noninvasively derived and their dependencies outlined. In 8 of 15 patients, direct temperature measurements in reference points were available. We correlated the tumor MR temperatures with direct measurements, clinical response, and tumor features (volume and location), and found reasonable trends and correlations. Therefore, the mean T(MR) of the tumor might be useful as a variable to evaluate the quality and effectivity of heat treatments, and consequently as optimization variable. Feasibility of noninvasive MR thermography for regional hyperthermia has been shown and should be further investigated.

A practical approach to thermography in a hyperthermia/magnetic resonance hybrid system: Validation in a heterogeneous phantom

PURPOSE

This study investigates the feasibility and accuracy of noninvasive magnetic resonance (MR) monitoring for a system that includes a multiantenna applicator for part-body hyperthermia (SIGMA-Eye applicator, BSD-2000/3D) and a 1.5 Tesla MR tomograph (Siemens Magnetom Symphony).

METHODS

A careful electrical decoupling enabled simultaneous operation of both systems, the hyperthermia system (100 MHz, up to 1600 W) and the MR tomograph (63.9 MHz). We used the phase data sets of a gradient echo sequence (long echo time TE = 20 ms) according to the proton frequency shift (PFS) method to determine MR temperature changes. Data postprocessing and visualization was conducted in the software platform AMIRA-HyperPlan. Heating was evaluated in an elliptical Lucite cylinder of 50 cm length filled with tissue-equivalent agarose and a skeleton made from low-dielectric material to simulate the heterogeneity of a real patient. Multiple catheters were included longitudinally for direct thermometry (using Bowman high-impedance thermistors). The phantom was positioned in the 24-antenna applicator SIGMA-Eye employing the integrated water bolus (filled with deionized water) both for coupling the radiated power into the lossy medium and to enable a correction procedure based on direct temperature measurements.

RESULTS

In eight phantom experiments we monitored the heating in the applicator not only by repetitive acquisition of three-dimensional MR datasets, but also by measuring temperature-time curves directly at selected spatial positions. For the correction, we specified regions in the bolus. Direct bolus temperatures at fixed positions were taken to aim at best possible agreement between MR temperatures and these direct temperature-time curves. Then we compared additional direct temperature-position scans (thermal maps) for each experiment with the MR temperatures along these probes, which agreed satisfactorily (averaged accuracy of +/- 0.4-0.5 degrees C). The deviations decreased with decreasing observation time, temperature increase, and thermal load to the surroundings (corresponding to bolus heating)-estimating a resolution of, at best, +/- 0.2-0.3 degrees C. The acquired MR temperature distributions give also insight into limitations and control possibilities of regional hyperthermia (annular phased array technology) for various tumor sites.

CONCLUSIONS

On-line MR monitoring of regional hyperthermia by using the PFS method is feasible in a phantom setup and can be further developed for clinical applications.

[Principles, technology and indication of hyperthermia and part body hyperthermia]

Clinical hyperthermia with controlled alteration of temperature (40 to 44 degrees C) in the target area is used in interdisciplinary treatment concepts for tumor treatment in combination with radiation and/or radiotherapy. Besides the direct cytotoxic power of hyperthermia there is an immunomodulatory effect and a radiation and chemotherapy sensitizing effect in the heated tissue. Clinical hyperthermia is an invasive or non-invasive supply of energy to the body of the patient, which leads to an artificial heating of the tumor and the surrounded tissue. The clinical hyperthermic procedures should take into account the oncologic disease and its pattern of organ involvement. There are three different types of hyperthermia: local hyperthermia (LHT), regional hyperthermia (RHT) and part body hyperthermia (PBH). PBH is used to heat regions of the body in case of metastatic disease, e. g. to the abdomen. I and phase II trials could show that the effects of radiation and chemotherapy can be altered by the simultaneous addition of hyperthermia. Data of trials involving skin metastasis in malignant melanoma, local relapse in breast cancer, tumors of the head and neck with regional lymph node metastasis, as well as trials in colorectal tumors, bladder cancer, pancreatic cancer, cervical cancer and sarcoma are presented. The results shows, that response to treatment can be improved by hyperthermia.

Hyperthermia in combined treatment of cancer

Hyperthermia, the procedure of raising the temperature of tumour-loaded tissue to 40-43 degrees C, is applied as an adjunctive therapy with various established cancer treatments such as radiotherapy and chemotherapy. The potential to control power distributions in vivo has been significantly improved lately by the development of planning systems and other modelling tools. This increased understanding has led to the design of multiantenna applicators (including their transforming networks) and implementation of systems for monitoring of E-fields (eg, electro-optical sensors) and temperature (particularly, on-line magnetic resonance tomography). Several phase III trials comparing radiotherapy alone or with hyperthermia have shown a beneficial effect of hyperthermia (with existing standard equipment) in terms of local control (eg, recurrent breast cancer and malignant melanoma) and survival (eg, head and neck lymph-node metastases, glioblastoma, cervical carcinoma). Therefore, further development of existing technology and elucidation of molecular mechanisms are justified. In recent molecular and biological investigations there have been novel applications such as gene therapy or immunotherapy (vaccination) with temperature acting as an enhancer, to trigger or to switch mechanisms on and off. However, for every particular temperature-dependent interaction exploited for clinical purposes, sophisticated control of temperature, spatially as well as temporally, in deep body regions will further improve the potential.

Response to neoadjuvant chemotherapy combined with regional hyperthermia predicts long-term survival for adult patients with retroperitoneal and visceral high-risk soft tissue sarcomas

PURPOSE

To determine the efficacy of neoadjuvant chemotherapy combined with regional hyperthermia (RHT) for local tumor control and overall survival (OS) in adult patients with retroperitoneal or visceral (RP/V) high-risk soft tissue sarcomas (HR-STS).

PATIENTS AND METHODS

From 1991 to 1997, 58 patients with HR-STS at RP/V sites were prospectively treated with four cycles of etoposide, ifosfamide, and doxorubicin combined with RHT followed by surgery, adjuvant chemotherapy, and radiation.

RESULTS

Objective response rate assessable in 40 patients was 13% (five partial responses). Including minor responses (n = 8), the radiographic response rate was 33%. The pathologic response rate assessable in 26 patients after surgical resection was 42%. Median OS was 31 months. At a median observation time of 74 months, 5-year probability of local failure-free survival (LFFS), distant metastasis-free survival, event-free survival, and OS were 25%, 51%, 20%, and 32%, respectively. Averaged minimum temperatures (T(min)) and time-averaged temperatures achieved in 50% (T(50)) and 90% (T(90)) of all measured tumor sites differed significantly between responders and nonresponders (T(min), 39.3 degrees C v 38.0 degrees C; P =.002; T(50), 40.9 degrees C v 40.3 degrees C; P =.038; T(90), 40.1 degrees C v 39.3 degrees C; P =.017). At 5-year follow-up, probability of LFFS (59% v 0%; P <.001) and OS (60% v 10%; P <.001) was significantly in favor of patients responding to neoadjuvant thermochemotherapy.

CONCLUSION

Response to neoadjuvant chemotherapy combined with RHT is predictive for an improved local tumor control resulting in a long-term survival benefit for patients with HR-STS at unfavorable RP/V sites; however, the impact of RHT has to be defined in a randomized phase III trial.

Neoadjuvant chemotherapy combined with regional hyperthermia (RHT) for locally advanced primary or recurrent high-risk adult soft-tissue sarcomas (STS) of adults: long-term results of a phase II study

In this phase II study, activity and safety of neoadjuvant regional hyperthermia (RHT) combined with chemotherapy was investigated in 59 patients with primary advanced or recurrent high-risk soft-tissue sarcoma (STS). Patients received four EIA cycles consisting of etoposide, ifosfamide and doxorubicin combined with RHT followed by surgical resection and adjuvant treatment. The overall objective response (OR) rate was 17%, with one complete (2%) and eight partial (15%) responses. In addition, 13 minor responses (25%) were seen. At time of surgery, complete necrosis (pCR) occurred in 6 patients and >75% necrosis (favourable histological response (FHR)) in 12 patients. At the completion of protocol treatment, 36 patients were rendered disease-free which was significantly associated with the initial radiographic and/or pathological tumour response (P=0.004). Treatment-related toxicity was acceptable overall. At a medium follow-up of 82 months, local treatment failure occurred in 33 patients, median overall survival (OS) was 52 months, and the 5-year survival rate was 49% (95% confidence interval (CI): 36-61%). OS which did not differ for extremity versus non-extremity STS (P=0.21) was better for patients responding to EIA combined with RHT (P<0.01).

Treatment of primary, recurrent or inadequately resected high-risk soft-tissue sarcomas (STS) of adults: results of a phase II pilot study (RHT-95) of neoadjuvant chemotherapy combined with regional hyperthermia

The efficacy of thermochemotherapy in adult patients with primary, recurrent or inadequately resected non-metastatic high-risk soft-tissue sarcomas (STS) was assessed. 54 patients were prospectively treated with four cycles of etoposide, ifosfamide and doxorubicin (EIA) combined with regional hyperthermia (RHT) followed by surgery, another four cycles of EIA without RHT and external beam radiation. The objective response rate was 16% and at a median follow-up time of 57 months, the 4-year estimated rates of local failure-free survival (LFFS), distant metastasis-free survival (DMFS), event-free survival (EFS) and overall survival (OS) were 59% (95% confidence interval (CI) 45-73%), 59% (95% CI 44-73%), 26% (95% CI 14-38%) and 40% (95% CI 27-53%), respectively. OS was in favour of patients responding to neoadjuvant treatment (P=0.073). In comparison to a preceding phase II study including pre- and postsurgical thermochemotherapy (RHT-91), at a 4-year follow-up the RHT-95 study cohort showed an inferior LFFS rate (P=0.027), but this did not affect DMFS (P=0.558) or OS (P=0.126). Hence, postsurgical thermochemotherapy seems critical for local tumour control without affecting survival.

Preoperative radiochemotherapy in locally advanced or recurrent rectal cancer: regional radiofrequency hyperthermia correlates with clinical parameters

PURPOSE

Preoperative radiochemotherapy (RCT) is a widely used means of treatment for patients suffering from primary, locally advanced, or recurrent rectal cancer. We evaluated the efficacy of treatment due to additional application of regional hyperthermia (HRCT) to this conventional therapy regime in a Phase II study, employing the annular phased-array system BSD-2000 (SIGMA-60 applicator). The clinical results of the trial were encouraging. We investigated the relationship between a variety of thermal and clinical parameters in order to assess the adequacy of thermometry, the effectiveness of hyperthermia therapy, and its potential contribution to clinical endpoints.

METHODS AND MATERIALS

A preoperative combination of radiotherapy (1.8 Gy for 5 days a week, total dose 45 Gy applied over 5 weeks) and chemotherapy (low-dose 5-fluorouracil [5-FU] plus leucovorin in the first and fourth week) was administered to 37 patients with primary rectal cancer (PRC) and 18 patients with recurrent rectal cancer (RRC). Regional hyperthermia (RHT) was applied once a week prior to the daily irradiation fraction of 1.8 Gy. Temperatures were registered along rectal catheters using Bowman thermistors. Measurement points related to the tumor were specified after estimating the section of the catheter in near contact with the tumor. Three patients with local recurrence after abdominoperineal resection, had their catheters positioned transgluteally under CT guidance, where the section of the catheter related to the tumor was estimated from the CT scans. Index temperatures (especially T(max), T(90)) averaged over time, cumulative minutes (cum min) (here for T(90) > reference temperature 40.5 degrees C), and equivalent minutes (equ min) (with respect to 43 degrees C) were derived from repetitive temperature-position scans (5- to 10-min intervals) utilizing software specially developed for this purpose on a PC platform. Using the statistical software package SPSS a careful analysis was performed, not only of the variance of thermal parameters with respect to clinical criteria such as toxicity, response, and survival but also its dependency on tumor characteristics.

RESULTS

The rate of resectability (89%) and response (59%) were high for the PRC group, and a clear positive correlation existed between index temperatures (T(90)) and thermal doses (cum min T(90) >/= 40.5 degrees C). Even though the overall 5-year survival was encouraging (60%) and significantly associated with response, there was no statistically significant relationship between temperature parameters and long-term survival for this limited number of patients. However, nonresectable tumors with higher thermal parameters (especially cum min T(90) >/= 40.5 degrees C) had a tendency for better overall survival. We found even higher temperatures in patients with recurrences (T(90) = 40.7 degrees C versus T(90) = 40.2 degrees C). However, these conditions for easier heating did not involve a favorable clinical outcome, since surgical resectability (22%) and response rate (28%) for the RRC group were low. We did not notice any other dependency of thermal parameters to a specific tumor or patient characteristics. Finally, neither acute toxicity (hot spots) induced by hyperthermia or RCT nor perioperative morbidity were correlated with temperature-derived parameters. Only a higher probability for the occurrence of hot spots was found during treatment with elevated power levels.

CONCLUSION

In this study with two subgroups, i.e., patients with PRC (n = 37) and RRC (n = 18), there exists a positive interrelationship between thermal parameters (such as T(90), cum min T(90) >/= 40,5 degrees C) and clinical parameters concerning effectiveness. Additional hyperthermia treatment does not seem to enhance toxicity or subacute morbidity. Procedures to measure temperatures and to derive thermal parameters, as well as the hyperthermia technique itself appear adequate enough to classify heat treatments in

Clinical evaluation and verification of the hyperthermia treatment planning system hyperplan

PURPOSE

A prototype of the hyperthermia treatment planning system (HTPS) HyperPlan for the SIGMA-60 applicator (BSD Medical Corp., Salt Lake City, Utah, USA) has been evaluated with respect to clinical practicability and correctness.

MATERIALS AND METHODS

HyperPlan modules extract tissue boundaries from computed tomography (CT) images to generate regular and tetrahedral grids as patient models, to calculate electric field (E-field) distributions, and to visualize three-dimensional data sets. The finite difference time-domain (FDTD) method is applied to calculate the specific absorption rate (SAR) inside the patient. Temperature distributions are calculated by a finite-element code and can be optimized. HyperPlan was tested on 6 patients with pelvic tumors. For verification, measured SAR values were compared with calculated SAR values. Furthermore, intracorporeal E-field scans were performed and compared with calculated profiles.

RESULTS

The HTPS can be applied under clinical conditions. Measured absolute SAR (in W/kg), as well as relative E-field scans, correlated well with calculated values (+/-20%) using the contour-based FDTD method. Values calculated by applying the FDTD method directly on the voxel (CT) grid, were less well correlated with measured data.

CONCLUSION

The HyperPlan system proved to be clinically feasible, and the results were quantitatively and qualitatively verified for the contour-based FDTD method.

Effects of a combined thermochemotherapy on markers of apoptosis, differentiation and adhesion in the human mammary carcinoma MX-1. A light microscopic and immunohistochemical study

The susceptibility to apoptotic stimuli, the degree of differentiation and the adhesive properties are important determinants of a tumor's biological behavior and of the possibility of it's being influenced by treatment. In this study we examined the effects of a combined thermochemotherapy, consisting of the administration of the alkylating agents ifosfamide or mafosfamide combined with hyperthermia at 41 degrees C for one hour, applied to the human mammary carcinoma MX-1. We concentrated our observations on the apoptosis-associated proteins bax and bcl-2, on cytokeratin and vimentin as markers of differentiation, on desmosomes and on the antiadhesive epithelial membrane antigen episialin. These proteins were visualized immunohistochemically in cultured cells in vitro as well as in xenotransplants growing in nude mice in vivo. We found that the susceptibility of the surviving cells to apoptotic stimuli, measured by the bax/bcl-2 ratio, was much higher after a combined thermochemotherapy than after chemotherapy or thermotherapy alone. Many of these cells could probably be forced into apoptosis by later applying another kind of anticancer therapy. With regard to the expression of episialin after thermochemotherapy, fewer cells possessed an antiadhesive and, therefore, potentially invasive capacity. The number of desmosomes seemed not to be affected. As to their higher expression of cytokeratin and their unchanged expression of vimentin, the surviving cells appear to be more differentiated. Since these results could be observed in vivo as well as in vitro, it seems likely that, apart from its influence on the perfusion of the tumor, the amplification of the cytostatic efficacy of the chemotherapy by hyperthermia must be mediated by a direct mechanism.

[Phase II study on preoperative radio-chemo-thermotherapy in locally advanced rectal carcinoma]

BACKGROUND

Recent studies show that preoperative radio-chemotherapy can increase resectability and local control of locally advanced rectal carcinomas. Additional regional hyperthermia might increase remission rates and tumor response. We therefore tested regional hyperthermia together with radio-chemotherapy in a phase-II study on locally advanced rectal carcinomas.

PATIENTS AND METHODS

Thirty-seven patients with primary advanced stage uT3/T4 rectal carcinomas were treated with preoperative radio-chemo-thermo-therapy. The initial tumor depth was determined using endosonography, CT, and MRI. Radiotherapy was carried out in prone position (on a belly board) using standard techniques, with 5 x 1.8 Gy per week up to 45 Gy at the reference point. 5-Fluorouracil (300 to 500 mg/m2) was administered with low doses of leucovorin (50 mg) on days 1 to 5 and 22 to 28. The patients were treated with regional hyperthermia each week prior to radiotherapy and simultaneously with chemotherapy, using the Sigma 60 ring from the BSD-2000 system. Temperature/position curves and temperature/time curves were recorded in endocavitary (endorectal) catheters in tumor contact and as well in bladder and vagina. Following endosonographic restaging, the operation was carried out 4 to 6 weeks after the end of preoperative therapy and adjuvant chemotherapy continued in four cycles. In cases where tumors were non-resectable, a boost up to 64 Gy was aimed.

RESULTS

Thirty-one of the 37 patients (84%) with primary carcinoma proved locally R0-resectable. In addition we had 1 R1-resection (3%) and 5 non-resectable tumors (13%). Among the resected tumors, 53% experienced a reduction of depth infiltration from the initial endosonographic stage during preoperative therapy. The actuarial survival rate after 4 years is 65% (free of progression 57%). The actuarial 4-year survival rate was particularly favorable for the group of responders. Overall, the preoperative multimodal therapy was well tolerated, and premature termination was only necessary in 1 case (3%). Grade III/IV toxicities in the intestine and skin were reduced as far as possible by field blockings and cooling of the perineal region. They occurred only in 5/37 patients (13%) at the intestine and in 6/37 patients (16%) at the skin. The thermal data were subjected to a statistical analysis. The quality of temperature distribution (T90, cum min T90 > or = 40.5 degrees C) depends on the power level and relative power density. The response (reduction of tumor size or depth infiltration) correlated significantly with quality parameters of the temperature distributions. This dependency is found as a trend for progression-free survival, too.

CONCLUSIONS

Preoperative radio-chemo-thermo-therapy proved to be practical and effective, with encouraging remission rates and excellent local control rates. For this reason, a phase-III study to test regional hyperthermia has been initiated. At the same time, certain technical improvements are still under development for regional hyperthermia.

Design and test of a new multi-amplifier system with phase and amplitude control

The clinical relevance of the radiofrequency regional hyperthermia (RF-RHT) as an adjuvant cancer therapy grows continuously. Simulation studies for optimization of RF-RHT based on the annular phased array systems have shown a significant improvement of power deposition patterns with increasing number of channels. However, this probably requires higher phase accuracy and amplitude stability than are provided by presently used clinical systems, e.g. BSD-2000. Measurements performed on the BSD-200 electronic revealed phase inaccuracies up to +/- 20 degrees and errors in the power registration of +/- 20 W (up to +/- 50 W in the low power range). These errors are further enhanced by the mismatching of the external load (antenna applicator) and thermal instabilities. To achieve the required phase accuracy and long-term stability in the prototype of a new amplifier system, single-sideband (SSB) mixing in combination with direct digital synthesizers (DDS), in-phase and quadrature-phase (IQ) processing and phase-lock loop (PLL) were used. In the DDS's the actual phase of the output signal of each channel is calculated in real-time. No analogue control loop is involved that may cause thermal offset or drift problems. Each DDS operates at a low intermediate frequency (IF) of 1 MHz. To transform the phase information of this IF signal into the desired RF band, SSB mixing-up is performed. A second frequency source, operating as a local oscillator (LO) in the RF band, is required for this technique. Also, the frequency adjustment of the desired RF signal is performed in the LO. These phase and frequency adjustment units are followed by the high efficiency AB-class solid state amplifier unit. The phase and power level stability of the amplifier are controlled by means of digital PLL structures in conjunction with look-up tables. For this control test signals are coupled out by means of directional couplers. The phase control is based on very sensitive phase comparison. These digital control loops are programmable and allow the implementation of different control algorithms. The achieved long-term accuracy (95% confidence interval) is +/- 1-3 W for output power levels ranging from 10-100 W, and +/- 1 degree for phase differences between each channel and a reference signal at a constant power level, and +/- 1.5 degrees for phase difference values at variable power levels between 10-100 W. In conclusion, the new amplifier system is smaller and more efficient than presently available commercial systems.

Rationale for using invasive thermometry for regional hyperthermia of pelvic tumors

PURPOSE

Invasive thermometry for regional hyperthermia is time-consuming, uncomfortable, and risky for the patient. We tried to estimate the benefit/cost ratio of invasive thermometry in regional hyperthermia using the radiofrequency system BSD-2000.

METHODS AND MATERIALS

We evaluated 182 patients with locally advanced pelvic tumors that underwent regional hyperthermia. In every patient a tumor-related temperature measurement point was obtained either by invasive or minimally invasive catheter measurement tracks. In the earlier period for every patient an intratumoral measurement point was decided as obligatory and intratumoral catheters were implanted intraoperatively, CT guided, or under fluoroscopy. In the later period, invasive thermometry often was avoided, if a measurement point in or near the tumor was reached by an endoluminally inserted catheter (rectal, vaginal, cervical, urethral, or vesical). For every patient side effects and complications referred to thermometry were evaluated and compared with the potential benefit of the invasively achieved temperature data. The suitability of endolumimally registered temperatures is analyzed to estimate local feasibility (specific absorption rate achieved) and local effectiveness (thermal parameters correlated with response).

RESULTS

In 74 of 182 patients invasive thermometry was performed, at most CT-guided for soft tissue sarcomas and rectal recurrences. In 14 of 74 (19%) side effects such as local inflammation, pain, or abscess formation occurred that enforced removal of the catheter. However, local problems were strongly correlated with the dwell time of the catheter and nearly never occurred for dwell times less than 5 days. Fortunately, no fatal complications (e.g., bleeding or perforation) occurred during or after implantation which could be attributed to the invasive thermometry procedure. Endoluminal tumor-related temperature rises per time unit (to estimate power density) were correlated with intratumoral rises at the same patients (where both measurements were available). For a subgroup of patients pooled in two Phase II studies with rectal (n = 37) and cervical (n = 18) carcinomas thermal parameters derived from endoluminal measurements were correlated with response or local control, resp.

CONCLUSIONS

If a tumor-related endoluminal temperature measurement point is available, additional invasive thermometry gives no further information to improve the power deposition pattern. For primary rectal and cervical cancer, and probably as well for prostate, bladder and anal cancer, endoluminal measurements are suitable to estimate local feasibility and effectiveness. Therefore, invasive thermometry is dispensable in the majority of patients. In some selected cases, temperature measurement in the tumor center is required to estimate the maximum temperature. In those cases, dwell time of catheters should be minimized--and it should be considered to perform invasive thermometry at the beginning (one or two heat treatments).

Treatment of advanced refractory sarcomas with ifosfamide and etoposide combination chemotherapy

Chemotherapy options for resistant advanced-stage sarcomas are limited and in most cases disappointing. In a phase II study, we treated 26 consecutive patients with refractory advanced sarcoma with ifosfamide and etoposide combination chemotherapy. All patients had received prior doxorubicin- and/or cyclophosphamide-based chemotherapies. Seventeen patients were male and 9 were female. The patients' median age was 35 years (range: 19-67 years). A total of 24 patients were eligible for evaluation of responses. Seven patients had a complete response (CR) (29.1%), 3 had a partial response (PR) (12.5%), 3 had stable disease (SD) (12.5%), and 11 had progressive disease (PD) (45.9%). An overall 41.6% objective response was achieved. Median time to treatment failure was 13.3 months. A total of 108 cycles of therapy were evaluable for evaluation of toxicity. Myelosuppression, observed in 55.5% of the treatment courses, was the major dose-limiting toxicity. Nausea and vomiting, seen in 64% of the courses, were the most important nonhematological side effects. Alopecia was almost universal. Hemorrhagic cystitis was observed in only 1 patient. We have concluded that the combination of ifosfamide, mesna, and etoposide is effective in advanced refractory sarcomas, and has acceptable toxicity.

Treatment of children with relapsed soft tissue sarcoma: report of the German CESS/CWS REZ 91 trial

BACKGROUND

The present study was performed to evaluate the possibilities of relapse treatment in patients heavily pretreated for a soft tissue sarcoma.

PATIENTS AND METHODS

Prospective, multicenter study in 44 soft tissue sarcoma (STS) patients with first relapse. Primary diagnosis was embryonal rhabdomyosarcoma (RME) in 17 patients, alveolar rhabdomyosarcoma (RMA) in 13, primitive neuroectodermal tumor (PNET) in 6, and miscellaneous soft tissue sarcomas in 8 patients. Initial chemotherapy consisted of carboplatin/etoposide combination (150 mg/m2 each, days 1 to 4) followed by local therapy including surgical treatment and, whenever possible, radiotherapy.

RESULTS

In 11/17 patients without primary tumor resection, CR or PR was achieved following the initial two cycles of chemotherapy (61%). The probability of event-free survival (pEFS) for RME patients was 0.41 +/- 0.12 at 5 years, and 0.25 +/- 0.12 for RMA patients. But, in contrast no PNET patient or patient with another soft-tissue sarcoma achieved long-term remission. Additional local radiotherapy significantly (P = 0.002) improved pEFS (3-year estimates of 0.23 +/- 0.2 vs. 0.1 +/- 0.1 in patients without radiotherapy).

CONCLUSIONS

In patients with RME, relapse treatment employing a carboplatin/etoposide combination may induce a second remission in approximately 40% of patients. Surgical excision and additional local radiotherapy seem to be essential to maintain a stable remission. In patients with RMA or PNET, however, this treatment strategy is of no long-term benefit.

Preoperative hyperthermia combined with radiochemotherapy in locally advanced rectal cancer: a phase II clinical trial

OBJECTIVE

A prospective phase II study was performed to determine the feasibility and efficacy in terms of response rate, resectability, and morbidity in patients with locally advanced rectal cancer who received preoperative regional hyperthermia combined with radiochemotherapy (HRCT).

SUMMARY BACKGROUND DATA

Recent studies suggest that preoperative radiochemotherapy in locally advanced rectal cancer can induce downstaging, but after resection the incidence of local recurrences remains high. Hyperthermia (HT) may add tumoricidal effects and improve the efficacy of radiochemotherapy in a trimodal approach.

PATIENTS AND METHODS

Thirty-seven patients with histologically proven rectal cancer and T3 or T4 lesions, as determined by endorectal ultrasound and computed tomography, entered the trial. 5-Fluorouracil (300-350 mg/m2) and leucovorin (50 mg) were administered on days 1 to 5 and 22 to 26. Regional HT using the SIGMA 60 applicator (BSD-2000) was given once a week before radiotherapy (45 Gy with 1.8-Gy fractions for 5 weeks). Surgery followed 4 to 6 weeks after completion of HRCT.

RESULTS

Preoperative treatment was generally well tolerated, with 16% of patients developing grade III toxicity. No grade IV complications were observed. The overall resectability rate was 32 of 36 patients (89%), and 31 resection specimens had negative margins (R0). One patient refused surgery. In 5 patients (14%), the histopathologic report confirmed no evidence of residual tumor (pCR). A partial remission (PR) was observed in 17 patients (46%). The survival rate after 38 months was 86%. In none of the patients was local recurrence detected after R0(L), but five patients developed distant metastases.

CONCLUSION

Preoperative HRCT is feasible and effective and may contribute to locoregional tumor control of advanced rectal cancer, which is to be proven in an ongoing phase III trial.