Non-operative therapies for colorectal liver metastases

Abstract

Locoregional therapies for colorectal liver metastases complement systemic therapy by providing an opportunity for local control of hepatic spread. The armamentarium for liver-directed therapy includes ablative therapies, embolization, and stereotactic body radiation therapy. At this time, prospective studies comparing these modalities are limited and decision-making relies on a multidisciplinary approach for optimal patient management. Herein, we describe multiple therapeutic non-surgical procedures and an overview of the results of these treatments.

Keywords: Colon cancer; ablation; embolization; liver metastases; radiation.

Figure 1

Mechanism of radiofrequency ablation (RFA). Rapidly alternating electrical current produces ionic oscillations in bipolar water molecules, which generate frictional heat.

Figure 2

RFA electrode probe. RFA, radiofrequency ablation.

Figure 3

Pre and post-RFA appearance of colorectal hepatic metastasis. (A) Intra-procedural CT demonstrates RFA probe within left lobe hepatic metastasis; (B) post-procedure CT 6 months status post RFA demonstrates left lobe liver ablative lesion with no residual perfusion. RFA, radiofrequency ablation.

Figure 4

(A) Pre-radioembolization CT demonstrates enhancing colorectal hepatic metastasis; (B) immediate post-radioembolization bremsstrahlung scan demonstrates activity within the hepatic metastasis consistent with selective uptake of radioactive Y90 microspheres by the lesion; (C) 6-month post-treatment CT demonstrates complete response of the lesion.

Figure 5

Two colorectal metastases at locations not amenable to RFA were treated with SBRT. RFA, radiofrequency ablation; SBRT, Stereotactic body radiotherapy.

Figure 6

A solitary lesion in a non-surgical candidate, treated with RFA. RFA, radiofrequency ablation.

Figure 7

Diffuse liver metastases treated with radioembolization.