Hepatic cryosurgery with intraoperative ultrasound monitoring for metastatic colon carcinoma
T. S. Ravikumar, R. Kane, B. Cady, R. L. Jenkins, W. McDermott, G. Onik, M. Clouse and G. Steele Jr
We utilized cryosurgery with intraoperative ultrasound (IOUS) monitoring in
ten patients to treat multiple unresectable hepatic metastases from
colorectal carcinoma. The liver was exposed at laparotomy, and tumors were
subjected to three cycles of freezing (eight minutes each) and thawing.
Freezing was monitored by IOUS, which visualized frozen tumor as a
hyperechoic rim with posterior acoustic shadowing. Frozen normal liver
appeared hypoechoic after thawing compared with normal unfrozen liver.
There were no significant complications. The follow-up ranged from four
months to 17 months (median, 7.5 months). Tumor response was documented by
pathologic findings (coagulative necrosis), progressive fall of
carcinoembryonic antigen levels, and computed tomographic scan evidence of
necrosis and shrinkage of tumor. One patient underwent repeated laparotomy
five months after cryosurgery and had the frozen lesions resected; there
was no residual tumor. This study establishes the technical feasibility and
antitumor response of hepatic cryosurgery and the use of IOUS for precise
localization and monitoring of cryoablations.
