Different story for low liver burdens
The Oslo investigators caution that, despite the findings, liver transplant for colorectal liver metastases “should still be considered a work in progress.”
The Oslo team says that to avoid “the futile use of liver grafts,” prospective research is needed to clearly identify colorectal liver metastases patients “who would benefit the most” from transplant.
Patients with extensive nonresectable metastases seem to be high on the list, but there might also be a role in resectable disease, say the study authors. One scenario, for instance, would be one in which PVE fails to expand the liver enough to allow resection; this was the case in 15 of the 53 PVE patients in the study.
As for patients with low liver tumor burden, transplant didn’t seem to offer much long-term survival benefit; 5-year OS was 72.4% among 21 low-burden transplant patients, vs. 69.3% among 23 who underwent PVE and resection.
Right-sided disease – having a primary tumor in the ascending colon, a known predictor of worse outcomes – might also prove to be a contraindication. The median OS after liver transplant was 12.2 months among patients with right-sided primaries and high-burden liver metastases. No such patients were alive at 5 years. On the other hand, the median OS was 59.9 months, and the 5-year OS was 45.3% among high-burden patients with left-sided primaries.
A call for a consortium
In a second editorial, Yuman Fong, MD, of the City of Hope Medical Center, Duarte, Calif., is less enthusiastic than the pair from Cincinnati. He calls the data “intriguing” but emphasizes that “we must recognize that cadaveric livers for transplant remain a finite resource,” and about 1,000 people die annually while on the waiting list in the United States.
The Cincinnati editorialists call for a multicenter consortium “for the cancer community to increase our understanding of this indication” and “pave the way for liver transplant as an option for colorectal liver metastases, just like we have for hepatocellular carcinoma, unresectable hilar cholangiocarcinoma, and metastatic neuroendocrine tumor.”
The investigators note that survival with transplant might be better because liver resection leaves behind microscopic disease that leads to liver recurrence. Most of the transplant patients in the study also experienced relapse, but recurrence after transplant tends to occur in the lungs with small, slow-growing lesions that are amenable to resection.
The study was funded by Oslo University Hospital, the Norwegian Cancer Society, and the South-Eastern Norway Regional Health Authority. The investigators and the editorialists in Cincinnati have disclosed no relevant financial relationships. Dr. Fong is a consultant for Medtronic and Johnson & Johnson and has received royalties from Merck and Imugene.
A version of this article first appeared on Medscape.com.