Drug & Device Development

Stem cell preconditioning boosts liver volume before resection

Last Updated: 2012-01-02 13:00:33 -0400 (Reuters Health)

By David Douglas

NEW YORK (Reuters Health) - Infusion of bone marrow-derived stem cells after selective portal vein embolization (PVE) was associated with better outcomes of extended right hepatectomy in a retrospective study from Germany.

"Our primary goal is to improve liver growth prior to resection for malignant disease," senior author Dr. Wolfram Trudo Knoefel, of the University of Dusseldorf, told Reuters Health by email.

He and his colleagues had previously shown that portal venous infusion with CD133-positive bone marrow-derived stem cells increases hepatic proliferation compared to PVE alone.

To determine what impact this might have on outcomes, the researchers reviewed data on 40 patients from their center, most of whom had established liver malignancies.

Eleven patients had been preconditioned with PVE and CD133-positive bone marrow-derived stem cells; 11 were pretreated with PVE alone; and the remaining 18 patients, with no presurgical treatment, served as controls. There were no complications associated with the procedures, the authors report in the January issue of Annals of Surgery.

Fourteen days after PVE, patients given stem cells had a higher mean hepatic growth of segments II/III than those who had PVE alone (139 vs. 63 mL, p=0.004).

At postoperative day seven, there were no significant differences across the three groups in general and oncological characteristics or functional parameters.

Major postoperative complication rates related to resection were high (46%), but again there were no significant differences among groups in that regard or in 30-day mortality.

The patients were followed for a median of 28 months. Median overall survival was 27 months in the combination group, 20 months in those with PVE alone and six months in the control group.

On multivariate analysis, freedom from major complications, coagulation status on day seven post-surgery (i.e., INR < 1.4), and presurgical expansion of the future liver remnant volume were positively associated with overall survival.

A post-hoc comparison showed that patients who received stem cell pretreatment survived significantly longer than those in the control group (p=0.028), whereas patients pretreated with PVE alone did not (p=0.094).

However, before widespread adoption of the approach, "it is obvious that safety aspects have to be addressed in a larger number of patients," the researchers write.

"The approach is logistically demanding," added Dr. Knoefel. "Therefore, it is, so far, used only at our center."

He and his colleagues are training personnel from other centers, but "to become routine it may well take another five years."

The researchers note that neither PVE nor stem cell application "seems to be associated with the occurrence of local tumor growth or metastasis." They conclude that it "seems to be a safe and promising additive providing the opportunity of oncological resection with acceptable outcome."

SOURCE: http://bit.ly/s9utMq

Ann Surg 2012;255:79-85.