Reirradiation of primary brain tumours: survival, clinical response and prognostic factors.

Background And Purpose: First, the aim was to determine the survival and quality of life after reirradiation of relapsing primary malignant brain tumours. The second aim was to assess the influence of a set of potentially prognostic factors on survival.

Materials And Methods: Forty-two patients received reirradiation for recurring primary brain tumours.

Changes in tumor hypoxia measured with a double hypoxic marker technique.

Purpose: Development of a double hypoxic cell marker assay, using the bioreductive nitroimidazole derivatives CCI-103F and pimonidazole, to study changes in tumor hypoxia after treatments that modify tumor oxygenation.

Methods And Materials: Both hypoxic markers were visualized by immunohistochemical techniques to detect changes in hypoxic fraction induced by carbogen breathing (95% O(2) and 5% CO(2)) or hydralazine injection. The protocol was tested in a human laryngeal squamous cell carcinoma xenograft line.

Effects of nicotinamide and carbogen on oxygenation in human tumor xenografts measured with luminescense based fiber-optic probes.

Background And Purpose: In head and neck cancer, addition of both carbogen breathing and nicotinamide to accelerated fractionated radiotherapy showed increased loco-regional control rates. An assay based on the measurement of changes in tumor pO(2) in response to oxygenation modification could be helpful for selecting patients for these new treatment approaches.

Materials And Methods: The fiber-optic oxygen-sensing device, OxyLite, was used to measure changes in pO(2), at a single position in tumors, after treatment with nicotinamide and carbogen in three human xenograft tumor lines with different vascular architecture and hypoxic patterns.

Optical sensor-based oxygen tension measurements correspond with hypoxia marker binding in three human tumor xenograft lines.

Hypoxia has a negative effect on the outcome of radiotherapy and surgery and is also related to an increased incidence of distant metastasis. In this study, tumor pO(2) measurements using a newly developed time-resolved luminescence-based optical sensor (OxyLitetrade mark) were compared with bioreductive hypoxia marker binding (pimonidazole). Single pO(2) measurements per tumor were compared to hypoxia marker binding in tissue sections using image analysis.