Hepatic cryotherapy: double-freeze cycles achieve greater hepatocellular injury in man.

Hepatic cryotherapy is a relatively new technique used to treat both primary and secondary tumors. This paper concerns the changes in serum aspartate transaminase (AST) in 45 patients following both single and double freeze with partial thaw cycles. There was considerable elevation in serum AST, greatest on the day of operation, and there was a significantly higher peak AST following the double-freeze cycles (1159; SE, 117.5) compared with single-freeze/thaw procedures (437; SE, 61.7). This finding indicates greater hepatocellular disruption which may be important both in planning clinical hepatic cryosurgery to achieve adequate destruction and also to avoid the morbidity of the cryoshock phenomenon.