Tissue chemoablation

Abstract

Purpose: To provide an overview of the state of the art of tissue chemoablation in animal and human organs and cancers. We also describe our experience with the feasibility, predictability, and reproducibility of necrosis produced by needle chemoablative therapies including ethanol, hypertonic saline, and acetic acid solutions as well as gels in a porcine renal model.

Materials and methods: A MEDLINE search was performed for articles on animal and human tissue chemoablation published since 1965. In addition, at Washington University, experimental chemoablation was performed in pigs with 95% ethanol (4 mL), 24% hypertonic saline (4 mL), or 50% acetic acid (4 mL) solutions as well as in gel form.

Results: There is extensive literature on the use of chemoablation for liver metastases; recently, chemoablation of the prostate has become an area of research. Human studies have been limited to patients who are not surgical candidates or to investigational procedures performed prior to definitive prostatic surgery. Animal studies of renal chemoablation as a sole therapy have produced mixed results. In our studies, only acetic acid provided complete necrosis.

Conclusions: To date, ethanol chemoablation has been shown to be feasible and reproducible only for metastatic hepatic carcinoma. In urology, chemoablation is still very much in the investigational stage for both the prostate and the kidney. A significant drawback is that even in the gel form, the spread of the chemoablative substance through the tissue is irregular and unpredictable. In the future, chemoablation may become a more effective modality by combining it with radiofrequency or other energy sources.