Clinical

Laser ablation of liver metastases extends breast cancer survival

Last Updated: 2004-10-26 9:45:26 -0400 (Reuters Health)

NEW YORK (Reuters Health) - A method for ablating breast cancer metastases to the liver, which can be performed on an outpatient basis, is as effective as resection for extending survival, German researchers report.

The technique, magnetic resonance imaging-guided laser-induced interstitial thermotherapy (LITT), extended survival a mean 4.9 years after diagnosis in a series of 232 breast cancer patients with a total of 578 liver metastases, researchers report in the November issue of Radiology.

The question of whether such metastases should be removed surgically is still under discussion, Dr. Martin G. Mack of University Hospital Frankfurt and colleagues note. But recent small studies suggest resection can significantly extend survival for some breast cancer patients. While breast cancer that has spread to the liver generally indicates advanced disease with a poor prognosis, they add, metastases can be confined to the liver in from 5% to 12% of patients.

Average survival of breast cancer patients after diagnosis of liver metastases is 4 to 8 months, Dr. Mack and colleagues note. With systemic chemotherapy and hormonal treatment, the current "mainstay" of treatment for these patients, they add, survival averages 4 to 17 months.

Inclusion criteria for the current study were five or fewer liver metastases, none larger than 5 cm in diameter. The five major indications for MR-guided LITT were recurrence of tumor after partial resection (8.2%), general contraindications to surgery (2.6%), metastases to both lobes of the liver (45.2%), or refusal of surgery (25%).

Local tumor progression was seen in fewer than 5% of patients 6 months after LITT, while no additional local tumor growth was seen after 6 months. Average survival after the first LITT treatment was 4.2 years, and the complication rate was low.

LITT is less invasive and less expensive than surgery, Dr. Mack and colleagues note, and it does not preclude the simultaneous use of chemotherapy or hormone therapy. "Furthermore, the release of growth factors after resection has to be discussed, as well as the possibility for potentiating intrahepatic growth of metastases," they add. Minimal loss of liver parenchyma during LITT makes such effects unlikely with this procedure, while the less-invasive technique will also not trigger the temporary immune suppression seen with major surgery.

Bone metastases should not be a contraindication to the procedure, the researchers add, because their study found no significant difference in survival after LITT between patients with and without these metastases.

"In summary, MR-guided LITT is a safe and effective treatment for well-selected patients with liver metastases from breast cancer and is improving the survival of the patients," they conclude. "A major advantage of MR-guided LITT is that it can be easily performed with local anesthesia in an outpatient setting and has a low complication rate."

Radiology 2004;233:400-409.