Radio-Thermotherapy in Multimodal Surgical Treatment Concepts

Abstract

Hyperthermia can play a role in curative multimodal therapies of locally advanced malignancies. Firstly, the downstaging rate can be increased in pre-operative therapies (resectability, organ preservation), and secondly the local control can be improved. The synergistic effect of hyperthermia at 42-43 °C when combined with radiotherapy has been demonstrated in pre-clinical studies and in phase III studies as well. Furthermore, there are interactions with numerous cytotoxic drugs and un-specific as well as specific immunological processes, the value of which for clinical application has not yet been determined. The future of the clinical use of hyperthermia will be determined to a large extent by developments and improvements in the technology used, and the greatest potential lies in advancing radiofrequency equipment. Infrared whole-body hyperthermia also made progress in the past few years. We outline oncological concepts to apply hyperthermia for advanced rectal carcinomas, carcinomas of the bladder, oesophageal carcinomas and soft-tissue sarcomas. In this work we summarise results relating to hyperthermia performed on these tumour entities and details of possible therapeutic strategies. We also look at technical approaches to improved quality control of the heat delivery device, as well as planning, monitoring and verification of power application and temperature distribution.

What is on the Horizon for Hyperthermic Cancer Therapy?

“…Here, both approaches could be used: a reduced radiotherapy dose, promoted by hyperthermia using the complex TER factor [81][82][83]. Different review articles have summarized the sensitizing effect on classical ionizing radiation by hyperthermia [80,[84][85][86]. Considerable success has been presented for hyperthermia in combination with radiotherapy for deep-seated tumors [87,, and success has also been observed in shallow tumors .…”

Local Hyperthermia in Oncology – To Choose or not to Choose?

“…The heat-induced decrease of the DNA-dependent proteinkinase (DNA-PK), [121] is also a radio-sensitizer. Sensitizing the classical ionizing-radiation by hyperthermia has been well-known [122], [123] for a long time, and different review articles have summarized this knowledge [124], [125], [126], [127]. The advantage of combining heat-treatment with the classical ionizing-radiation is unambiguous, [128], [129], [84], the synergy between the methods is well known [130], [122] and successfully applied [131], [132], [106].…”

Hyperthermic Radiochemotherapy for Esophageal Cancer – Rationale and Concept of a Phase III Trial

“…To understand the action and mechanisms of hyperthermia and to develop optimal therapy modalities, biological phenomena as well as molecular metabolic and physiological events have to be considered [4,5]. Numerous basic studies have indicated that the antitumor effect of hyperthermia alone will not suffice and that there is a potential benefit when it is combined with radiation and chemotherapy.…”

“…The rationale for applying hyperthermia for cancer therapy with radiation is: 1) The S phase of the cell cycle is relatively radioresistant, hence it is sensitive to hyperthermia -and radiosensitization can be made selective by combining hyperthermia with irradiation; and 2) the relatively radioresistant hypoxic cells in the tumor may be selectively destroyed by the combination of hyperthermia and irradiation [6]. Data on hyperthermal sensitization effects are still incomplete, particularly its dependence on the time sequence and certain environmental factors (pH, pO 2 ) as well as its variation with the cell/tumor type [5]. The highest cytotoxic effect is observed when radiation is delivered simultaneously with heat, i.e.…”