Quo Vadis Oncological Hyperthermia (2020)?

Abstract

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 localregional 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.

External Basic Hyperthermia Devices for Preclinical Studies in Small Animals

“…While the tumor development time is dependent on the selected cell line, the study objective determines the desired tumor size. In general, for hyperthermia studies, the following tumor size ranges are considered to be experimentally suitable: for mice 50 to 700 mm 3 , for rats 100 to 2200 mm 3 , and for hamsters 50 to 150 mm 3 , as mentioned in the tables below. Overall, all of the described parameters should be considered during study design as these are able to influence the outcome of the experiment.…”

“…Application of mild hyperthermia (40–43 °C) is able to induce sublethal effects to the target region, which can induce beneficial mechanisms on both a tissue- and cellular level [ 1 , 2 ]. Clinical hyperthermia can be divided into three categories: local-, partial-, or whole body hyperthermia [ 3 ]. To study the application, effects in a treatment setting, and mechanisms involved in HT, different methods have been developed.…”

Targeting Hypoxia: Revival of Old Remedies

“…However, mixed patient outcomes put into question the efficacy of the combination of HT and radiation. Nevertheless, the analysis of five UK-led randomised trials of radiation and HT by Vernon et al, multi-centre trials by Overgaard et al, and studies by Jones et al and van der Zee et al suggested that the combination of HT and radiation was beneficial for some groups of patients, including locally recurrent breast cancer, cervical cancer, and melanoma [29][30][31][32][33][34][35][36][37][38][39]. Moreover, multiple studies further supported the beneficial effects of HT in paediatric and adolescent patients with a variety of tumour types, including malignant germ cell tumours, soft tissue sarcoma, and chondrosarcomas [40,41].…”

Marked local and distant response of heavily treated breast cancer with cardiac metastases treated by combined low dose radiotherapy, low dose immunotherapy and hyperthermia: a case report

“…Modulated electrohyperthermia (mEHT) is a form of HT that transmits radiofrequency energy into the tumor cell membrane to produce an electric field. This field causes lymphocytic and dendritic cells to penetrate the tumor to achieve pronounced immunogenic cell death (9,10). A combination of RT, mEHT, and immunotherapy may enable a rapid and sustained abscopal effect, as discussed in a retrospective study (11).…”