32p-labeled thio-tepa absorption in normal rat bladders: potential guide for intravesical chemotherapy in bladder cancer.

Bladders of normal rats were used to evaluate the absorption of thio-tepa after intravesical instillation. Thio-tepa labeled with 32P (radioactive phosphorus) was utilized to measure drug concentrations in bladder wall, liver, and bone marrow. Thio-tepa was rapidly absorbed into the general circulation, and significant amounts of isotope were found. Thio-tepa absorption patterns in the normal rat may serve as a guide in adjusting drug dosages when thio-tepa is used intravesically in human beings for the treatment of superficial, papillary bladder tumors.