Published online Oct 10, 2015. doi: 10.5306/wjco.v6.i5.142
Peer-review started: April 5, 2015
First decision: May 13, 2015
Revised: July 7, 2015
Accepted: July 24, 2015
Article in press: July 27, 2015
Published online: October 10, 2015
Processing time: 193 Days and 6.9 Hours
Colorectal liver metastasis (CRLM) is the major cause of death in patients diagnosed with colorectal cancer. The gold standard treatment of CRLM is surgical resection. Yet, in the past, more than half of these patients were deemed unresectable due to the inadequate future liver remnant (FLR). The introduction of efficient portal vein embolization (PVE) preoperatively allowed more resections of metastasis in CRLM patients by stimulating adequate liver hypertrophy. However, several experimental and clinical studies reported tumor progression after PVE which critically influences the subsequent management of these patients. The underlying pathophysiological mechanism of tumor progression post-PVE is still not fully understood. In spite of the adverse effects of PVE, it remains a potentially curative procedure in patients who would remain otherwise unresectable because of the insufficient FLR. Currently, the challenge is to halt tumor proliferation following PVE in patients who require this technique. This could potentially be achieved by either attempting to suppress the underlying oncologic stimulus or by inhibiting tumor growth once observed after PVE, without jeopardizing liver regeneration. More research is still required to better identify patients at risk of experiencing tumor growth post-PVE.
Core tip: This article discusses the effect of portal vein embolization (PVE) on colorectal liver metastasis (CRLM) growth and the suggested methods of prevention. In addition to presenting the various experimental and clinical studies emphasizing the suggested tumoral enhancing effect of PVE, this article highlights the concept of reversal of chemotherapy response, a potential effect occurring after PVE. This observation may impact significantly subsequent patients’ management as it may affect the resectability state of patients. Moreover, potential methods to prevent tumor growth are discussed in this article, indicating the need for further research in this field and highlighting the complex interaction between CRLM and liver regeneration milieu.