Human autopsy tissue distribution of the epipodophyllotoxins etoposide and teniposide.

Autopsy tissues were collected from ten patients who had received etoposide, 150-3480 mg, from 1 to 412 days antemortem and from five patients who had received teniposide, 234-1577 mg, from 3 to 52 days antemortem. Tissues were assayed for etoposide and teniposide using high-pressure liquid chromatography with electrochemical detection. Etoposide was detectable in tissues of three of four patients dying < 5 days after their last etoposide treatments to cumulative doses of 150-432 (median, 280) mg but was detectable in tissues of only one of six patients dying 7-412 (median, 37) days after their last etoposide treatment to a cumulative dose of 607-3600 (median, 1553) mg. The highest tissue concentrations were in the small bowel, prostate, thyroid, bladder, spleen, and testicle. Intermediate concentrations were found in the lymph node, skeletal muscle, adrenal gland, stomach, tumor, liver, lung, pancreas, and kidney, and the lowest concentrations were found in the heart, brain, diaphragm, vagina, and esophagus. Teniposide was detectable in one patient dying 3 days after a cumulative teniposide dose of 576 mg (spleen, prostate, heart > large bowel, liver, pancreas > thyroid, adrenal, stomach, small bowel, bladder, testicle, and skeletal muscle) but was not detectable in any tissue from four patients dying 5-52 (median, 8) days after their last treatment to a cumulative teniposide dose of 234-1577 (median, 520) mg. The very short tissue half-life contrasts with our previous observations for human autopsy tissue concentrations of mitoxantrone, doxorubicin, menogaril metabolites, diaziquone, and amsacrine. The short tissue half-life may help explain the schedule dependency of epipodophyllotoxin efficacy and may also help explain the lack of visceral toxicity of these compounds.