Search results for "Hyperthermia Treatment"
showing 5 items of 5 documents
Pathophysiological and vascular characteristics of tumours and their importance for hyperthermia: Heterogeneity is the key issue
2010
Tumour blood flow before and during clinically relevant mild hyperthermia exhibits pronounced heterogeneity. Flow changes upon heating are not predictable and are both spatially and temporally highly variable. Flow increases may result in improved heat dissipation to the extent that therapeutically relevant tissue temperatures may not be achieved. This holds especially true for tumours or tumour regions in which flow rates are substantially higher than in the surrounding normal tissues. Changes in tumour oxygenation tend to reflect alterations in blood flow upon hyperthermia. An initial improvement in the oxygenation status, followed by a return to baseline levels (or even a drop to below b…
MR Thermometry Data Correlate with Pathological Response for Soft Tissue Sarcoma of the Lower Extremity in a Single Center Analysis of Prospectively …
2020
Background: There is a strong biologic rationale for using locoregional hyperthermia in soft tissue sarcoma and a randomized trial reported significant improvements with hyperthermia. The aim of this study was to describe the opportunities of magnetic resonance (MR)-based thermometry in a cohort of soft tissue sarcoma patients undergoing combined radiotherapy and locoregional hyperthermia. Patients and Methods: For eleven evaluable patients, tumor volume (VTu) and a separate volume for temperature analysis with reliable temperature distribution (Vtherm) were contoured for every hyperthermia treatment (103 therapies). Temperature data were recorded for all tumors and were correlated with cli…
Vascular Meets of Localized Hyperthermia
2008
When hyperthermia is applied in vitro, no fundamental differences can be seen between the response to normal and tumor cells. In vivo however, selective damage of tumor cells can be achieved and this phenomenon can be largely attributed to a number of characteristic properties of the blood vessels within solid tumors. Changes in blood flow induced by hyperthermia can influence the response of a tumor to heat either by affecting the delivery of heat through changes in heat dissipation or by a modulation of the tumor microenvironment which may in turn affect the thermosensitivity of tumor cells. Studies in experimental and human tumors suggest however that an accurate prediction of changes in…
No Sustained Improvement in Tumor Oxygenation After Localized Mild Hyperthermia
2009
This study has attempted to address the controversy concerning sustained increases in tumor oxygenation upon localized mild hyperthermia. While some previous studies have reported transient increases, others have reported persistent increases in tumor oxygenation, lasting for upto 2 days after application of mild hyperthermia. In order to determine changes in oxygenation at clinically relevant tumor temperatures, experimental tumors in rats underwent localized hyperthermia at either 40, 41.8°C or 43°C for 1 h using water-filtered infrared-A irradiation. Oxygenation was continuously measured before, during and upto 60 min after hyperthermia in the tumors of anesthetized rats using oxygen-sen…
Oxygenation of Mammary Tumors: From Isotransplanted Rodent Tumors to Primary Malignancies in Patients*
1992
The role of oxygen in tumor cell proliferation, radiosensitivity, cytotoxicity of anticancer drugs and hyperthermia treatment has been the subject of a series of investigations (for reviews see Hall, 1988; Teicher et al., 1990, Vaupel et al., 1989a; Vaupel, 1990a,b). Despite the apparent importance of tumor oxygenation, data on pO2 values in solid tumors are mostly derived from experiments on rodents which might not necessarily reflect the variability of the clinical situation. Due to feasible techniques available now, considerable advances have been made in the past few years in the assessment of tumor hypoxia in patients (for reviews see Vaupel et al., 1989a; Vaupel, 1990a). The latter in…