Stereotactic Body radiation therapy for liver tumors with or without rotational intensity modulated radiation therapy.

BACKGROUND: To evaluate the feasibility and efficacy of Stereotactic body radiation therapy (SBRT) for primary liver lesions and liver metastases treated with linear accelerators with or without rotational Intensity Modulated RadioTherapy (IMRT). METHODS: Patients with either hepatocellular carcinoma, cholangiocarcinoma or metastatic liver lesions who had one to three lesions treated with SBRT in a single institution were retrospectively reviewed. Tumor response was evaluated according to EASL criteria 3 months after SBRT completion using MRI and/or abdominal CT scan. Responses were categorised as: Stable Disease (SD), Partial Response (PR), Complete Response (CR), Local Progression or Distant Progression in cases of new intra-hepatic lesions out-of-field or extra-hepatic metastases. Local Control (LC), Progression Free Survival (PFS), Overall Survival (OS) and treatment-related toxicities are reported. RESULTS: Between 2007 and 2012, 20 patients with a total of 24 lesions were treated with SBRT. Fourteen patients presented hepatocellular carcinoma (HCC), the others had either metastatic lesions from colorectal cancer (CRC) or cholangiocarcinoma. The median diameter of the lesions was 23 mm (5-98).The dose per fraction ranged from 6 to 20 Gy with a median total dose of 60 Gy (range: 36-60 Gy). The dose was prescribed to the 80% isodose line covering the PTV.The median follow-up was 24 months (15.7-29.7).The actuarial LC rate was 78% for patients with HCC and 83% for those with adenocarcinoma and cholangiocarcinoma. Median OS was 37 months and OS rates were 83% at 12 and 24 months for HCC and 100% for adenocarcinoma. PFS was 54% for HCC and 50% for other types of tumors at 24 months.Acute grade 3-4 toxicities occurred in 2 patients; a small proportion of the other patients experienced grade 1 or 2 toxicities. CONCLUSIONS: SBRT provides excellent local control with minimal side effects in selected patients.