Radiotherapy and hyperthermia. Analysis of clinical results and identification of prognostic variables

Abstract

Site-and tumor-specific data obtained from two groups of patients with head and neck and melanoma lesions, respectively, showed that both immediate response and response duration were enhanced by the addition of heat. Two important variables, however, such as tumor volume and "isoeffect thermal dose" appeared to influence local tumor control. The volume effect was less pronounced in the lesions treated with radiotherapy plus heat than in those treated with radiotherapy alone, suggesting that the addition of heat was more damaging to the large than to the small lesions. Furthermore, a striking isoeffect thermal dose-response relationship was shown in head and neck lesions. Those data were collected and used to design a mathematical model relating the probability of local control to clinical and treatment variables. The analysis shows that, by using the same radiation parameters, the probability of local tumor control is a function of both "isoeffect thermal dose" and tumor volume. Cancer 60:950-956,1987. HE CLINICAL EXPERIENCE accumulated in recent T years has clearly shown the potential of using hy-perthermia in addition to radi~therapy.'-~ Despite the inhomogeneity of patient population under treatment with regards to tumor size, location and histology, the results of all published studies have been surprisingly consistent in showing a constant therapeutic benefit of the combined modality over radiation alone.2 However, the information on specific tumor site and histology as well as the duration of the heat improved radiation response is limited5-' and deserves more careful investigation. The aim of this report is to discuss the results of the various treatment schedules, and to examine the mechanisms and factors affecting tumor response in general, as well as to provide site-and tumor-specific data with respect to initial response and response duration. Materials and Methods This study comprised 38 patients with 81 multiple neck node metastases from squamous cell carcinoma of

Hyperthermia as an adjuvant to radiation therapy of recurrent or metastatic malignant melanoma. A multicentre randomized trial by the European Society for Hyperthermic Oncology

“…The benefit of the combined treatment was in the same order as that previously described in uncontrolled studies [2,14,15,16,17,18,24]. The trial also confirms that total dose of radiation and tumour volume were other prominent prognostic factors [21,5].…”

“…This subsequently led to numerous uncontrolled studies which strongly suggested that adjuvant hyperthermia may increase the probability of controlling tumours by radiotherapy [2,3,4].…”

“…The fact that malignant melanoma has been found to respond well to radiotherapy given in large doses per fraction [13], and that the response apparently can be significantly improved by adding hyperthermia [2,5,14,15,16,17,18,19,20], makes this tumour type one of the most suitable clinical models for investigations of the interaction between radiotherapy and hyperthermia. The few fractions which can be spaced with relatively long intervals (several days) apparently without influencing the tumour control probability [21] allow treatment with hyperthermia in association with each radiation fraction without having the treatment compromised by the problems of thermotolerance [22,23].…”

Relationship between thermal dose and outcome in thermoradiotherapy treatments for superficial recurrences of breast cancer: Data from a phase III trial

“…However, when the animal data were restricted to squamous cell carcinomas, a relationship between thermal dose and duration of local response was found. Arcangeli et al (1,2) have also suggested such a relationship in a nonrandomized trial of hyperthermia as an adjunct to radiation in the treatment of neck node metastases from head and neck cancer. However, we interpret their data to show only an increase in initial response rate and question whether initial complete responders demonstrate any significant difference in kinetics of tumor regrowth or death as a function of thermal dose.…”

“…The hypothesis that negative results in previous Phase III randomized trials were due to inadequate heating, particularly in large tumors, is supported by Phase II human trial data (2,7,17,25,29).…”