**2.3 Local control with SBRT in hepatocellular carcinoma**

In the literature, there are multiple prospective studies, phase I and II, of SBRT in hepatocellular carcinoma with local control at 2 years ranging from 64 to 95% (**Table 1**).

Méndez Romero et al published the first prospective study in 2006. Eight patients had hepatocellular carcinoma with 11 lesions larger than 7 cm. Dose prescription was based on lesion size and the presence of cirrhosis. Local control at 1 year was 75%. Local failure was only observed at low doses (25 Gy in 5 fractions) [8]. Kang et al published a phase II study including patients with incomplete response to TACE and Child Pugh A. Local control at 2 years after SBRT (42–60Gy in three fractions) was 95% [6].

Two of the retrospective studies with the largest number of patients are the study by Sanuki et al, in 2013, and Su et al [9, 10]. The former included 185 patients with 185 lesions, <=5cm. The prescription doses were 40 and 35 Gy for Child Pugh A and B, respectively, in five fractions. Local control at 3 years was 91%19. In the study by Su et al, the authors who published the result of 114 Child Pugh A and 18 B noncandidates for other treatments, with 175 lesions, all less than or equal to 5 cm treated with 42–46 Gy in 3–5 fractions, local control at 1 year was 91% [10].

Recently, Rim et al performed a systematic review and meta-analysis analyzing 32 studies with 1950 patients, including local control and overall survival (OS) as the primary objective, and toxicity as a secondary objective. Local control at 3 years was 83.9%. The median tumor size was 3.3 cm (1.6–8.6 cm). The median dose, calculated in EQD2 (equivalent dose in 2 Gy fractions), was 48–114.8Gy (median 83.3 Gy). Concluding that SBRT in hepatocellular carcinoma provides excellent local control at 3 years [29]. Most of these studies include patients with hepatocellular carcinoma in Child Pugh A and B cirrhotic livers. In all of them, there is great heterogeneity in dosimetric parameters with doses ranging from 12 Gy in three fractions to 55 Gy in five fractions.
