Treatment of brain tumor patients. Hyperthermia, hyperbaric oxygenation, electric fields or nanoparticles

Despite considerable advancements in the therapy of malignant glioma in recent years with modern radiation and surgical techniques, alkylating and antiangiogenic chemotherapy, as well as molecular-based treatment decisions, treatment outcomes are mostly unsatisfactory. Understandably, patients often ask for experimental, sometimes unusual therapeutic modalities and this should be integrated into the clinical practice. In addition to experimental therapeutic approaches based on novel drugs, viral agents, immunotherapy and radiation approaches, experimental procedures of interest for patients particularly encompass mechanical approaches with the aim at physically altering the tumor tissue by temperature, oxygenation or magnetization. These mechanical procedures are based on intuitive concepts and promise fewer side effects than other experimental approaches. In addition, the requirements for approval by medical device regulations in terms of proof of efficacy are generally less stringent. As a consequence approaches, such as hyperbaric oxygenation, hyperthermia and electric fields, which are often heavily advertised and in part reimbursed by health insurances, have been used for many years, often by centers not specialized in the treatment of brain tumor patients, although sound data from prospective controlled clinical trials that determine which patients in which situation may benefit, are generally lacking. In this review we review these clinical therapeutic approaches.