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-sensitive catheters. The data obtained indicate that localized hyperthermia can lead, on average to an improved tumor oxygenation, although this improvement is generally transient and no longer evident 1 h after heating. Since clinically relevant increases in oxygenation enduring beyond the heating period were rarely seen, it would appear that an improvement in the efficacy of oxygen-dependent cancer therapy is unlikely to be achieved in the post-hyperthermia period.
Target Temperature Heat Period Hyperthermia Treatment Tumor Oxygenation Thermal Dose
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.
This is a preview of subscription content, log in to check access.
This work was supported by the Dr med. h.c. Erwin Braun Foundation, Basel, Switzerland.
Vaupel P, Ostheimer K, Müller-Klieser W (1980) Circulatory and metabolic responses of malignant tumors during localized hyperthermia. J Cancer Res Clin Oncol 98:15–29PubMedCrossRefGoogle Scholar
Vaupel P, Frinak S, Mueller-Klieser W et al. (1982) Impact of localized hyperthermia on the cellular microenvironment in solid tumors. Natl Cancer Inst Monogr 61:207–209Google Scholar
Vaupel P, Otte J, Manz R (1982) Oxygenation of malignant tumors after localized microwave hyperthermia. Radiat Environ Biophys 20:289–300PubMedCrossRefGoogle Scholar
Song C, Park H, Lee CK et al. (2005) Implications of increased tumor blood flow and oxygenation caused by mild temperature hyperthermia in tumor treatment. Int J Hyperthermia 21:761–767CrossRefGoogle Scholar
Iwata K, Shakil A, Hur W-J et al. (1996) Tumour pO2 can be increased markedly by mild hyperthermia. Br J Cancer Suppl 27:S217–S221PubMedGoogle Scholar
Hetzel FW, Chopp M, Dereski MO (1992) Variations in pO2 and pH response to hyperthermia: Dependence on transplant site and duration of treatment. Radiat Res 131:152–156PubMedCrossRefGoogle Scholar
Kelleher DK, Engel T, Vaupel PW (1995) Changes in microregional perfusion, oxygenation, ATP and lactate distribution in subcutaneous rat tumours upon water-filtered IR-A hyperthermia. Int J Hyperthermia 11:241–255PubMedCrossRefGoogle Scholar
Sun X, Li XF, Russell J et al. (2008) Changes in tumor hypoxia induced by mild temperature hyperthermia as assessed by dual-tracer immunohistochemistry. Radiother Oncol 88:269–276PubMedCrossRefGoogle Scholar