Oxygenation of locally advanced recurrent rectal cancer, soft tissue sarcoma and breast cancer.

Oxygen tension distributions (pO2) were measured in 20 patients with recurrent soft tissue sarcoma (n = 8), recurrent breast cancer (n = 9) and recurrent rectal cancer (n = 3) using computerized pO2 histography. A total of 35 measurements could be performed pretherapeutically. In 8 measurements there exist some problems with regard to clinical relevant bleeding or uncertainties of the tumor/normal tissue boundary. In general, there is a marked tumor-to-tumor variability even for tumors of the same histology. 5 of 8 soft tissue sarcomas, 1 of 3 recurrent rectal cancers, 4 of 9 breast cancers exhibited pO2 values between zero and 2.5 mmHg, i.e. tissue areas with less than half-maximum radiosensitivity.