Role of Hyperthermia in Breast Cancer Locoregional Recurrence: A Review

In patients with locoregional recurrences of breast cancer not suitable for resection, subsequent local control is difficult to maintain in previously irradiated areas when reirradiation alone or reirradiation with chemotherapy is used. Due to the limited number of treatment options there is a high risk of subsequent failure and uncontrollable local disease. In this group of patients, local hyperthermia combined with radiotherapy increases the clinical response and local control, adding limited acute and late toxicity, as has been shown in randomized trials. Hyperthermia is an artificial elevation of tissue temperature (range 40-44°C for 30-60 min). If hyperthermia is applied shortly before or after radiation, the effect of radiation is enhanced by influencing intratumoral hypoxia and by inhibiting sublethal damage repair in the tumor. Moreover, hyperthermia combined with radiation reduces the total dose of radiation needed compared to radiation alone, of which a higher dose is needed to obtain the same effect. Few data are available on the combination of radiotherapy and hyperthermia with chemotherapy, although the results of trimodality treatment consisting of reirradiation and hyperthermia together with liposomal doxorubicin are promising. Therefore, this literature review was performed to provide more comprehensive data on the mechanism and use of hyperthermia in locoregional recurrence of breast cance

Clinical feasibility of a high-resolution thermal monitoring sheet for superficial hyperthermia in breast cancer patients

Background: Accurate monitoring of skin surface temperatures is necessary to ensure treatment quality during superficial hyperthermia. A high-resolution thermal monitoring sheet (TMS) was developed to monitor the skin surface temperature distribution. The influence of the TMS on applicator performance was investigated, feasibility and ability to reliably monitor the temperature distribution were evaluated in a clinical study. Methods: Phantom experiments were performed to determine the influence of the TMS on power deposition patterns, applicator efficiency, and heat transfer of the water bolus for 434 and 915 MHz applicators. Clinical feasibility was evaluated in 10 women with locoregional recurrent breast cancer. Skin surface temperatures during consecutive treatments were monitored alternatingly with either standard Amsterdam UMC thermometry or TMS. Treatments were compared using (generalized) linear mixed models. Results: The TMS did not significantly affect power deposition patterns and applicator efficiency (1–2%), the reduced heat transfer of the water boluses (51–56%) could be compensated by adjusting the water bolus flow. Skin surface temperatures were monitored reliably, and no alteration of thermal toxicity was observed compared to standard Amsterdam UMC thermometry. Conclusion: Clinical application of the TMS is feasible. Power deposition patterns and applicator efficiency were not affected. Surface temperatures were monitored reliably