Background

There is limited outcome and safety data regarding liver irradiation in older patients that have been extensively pre-treated for metastatic liver disease (MLD). The aim is to review the outcome of patients who have received partial liver irradiation for MLD at our institution.

Method

Eligible patients had unresectable or medically inoperable MLD, Childs score A and performance status ≤2. Prior treatment with any modality of standard therapy (chemotherapy, surgery, radiofrequency ablation) was permitted. Adaptive radiotherapy management was used with planning target volume being patient specific according to tumour motion characterized on 4DCT and cine MRI. Dose was individualised according to the risk of radiation induced liver disease.

Results

From 12/2006 to 12/2011, 42 patients received liver SBRT, 37 for MLD. We report 34 patients (colorectal 27, breast 4, sarcoma 2 and anal cancer 1) with 40 lesions. Mean age 69 years (range 44-85). 83% had previously received chemotherapy (median 2 lines), 21% hepatic resection, and 35% RFA.

Mean GTV volume was 89.3 cc (range 2-614cc). Dose delivered ranged from 30-60 Gy in 10#. 1 patient had G3 toxicity (asymptomatic prolonged APTT). No higher grade toxicity was observed.

Mean follow up was 16.8 months (range 1.9-63.2). Median overall survival (OS) was 15.2 months. 1 and 2 year OS were 54% and 32% respectively. At last follow up 18/34 patients (53%) had not progressed in field. Mean time to in field progression was 12 months (range 1.4-52.3). Mean time to out of field progression was 11 months (range 1.2-63.2). The commonest sites of out of field progression were lung (35%) and liver (21%). 19/34 patients received chemo at progression.

Conclusion

In a heavily pre-treated population with MLD this approach of individualised dose SBRT appears safe.Further evaluation to ascertain the optimal sequencing of SBRT with standard therapies is required.