Image-guided radiation therapy for liver tumors gastrointestinal histology matters

Objectives: To describe the safety and efficacy of single-fraction and hypofractionated image-guided radiotherapy techniques for the treatment of large liver tumors.

Methods: Forty-six patients, with 50 tumors (10 primary liver tumors, 40 liver metastases) from March 2004 to March 2011 were reviewed. The maximal tumor diameter ranged from 1.2 to 11.3 cm (median, 4.2 cm). Eighty-seven percent of patients received prior systemic chemotherapy. Fifty-nine percent had prior invasive local therapy including surgery, ablation, or embolization. Twenty-five lesions were treated with hypofractionated therapy (24 to 30 Gy in 3 to 5 fractions), whereas 19 received a single fraction (18 or 24 Gy). Local control (LC) was calculated using competing risk analysis. Overall survival was calculated by the Kaplan-Meier method.

Results: Median follow-up for all patients was 29.8 months (range, 3 to 46 mo). The median survival was 15.4 months. The 1- and 2-year LC rates were 78% and 75%, respectively. Dose and tumor size had no significant effect on tumor progression. The local progression at 1 and 2 years was 29% and 32% for gastrointestinal (GI) histologies versus 0% for non-GI histologies (P = 0.02). Tumor volumes larger than 112 cm3 correlated with decreased survival (P = 0.05). Three patients developed late grade 3 GI stricture or ulceration.

Conclusions: Image-guided radiotherapy for liver tumors achieves good rates of LC with minimal toxicity at 1 and 2 years even in patients with large or recurrent disease that has been heavily pretreated. GI histology demonstrated decreased LC rates. Further management strategies should be considered in these patients.