Clinical study of recombinant adenovirus-p53 combined with fractionated stereotactic radiotherapy for hepatocellular carcinoma.

Objective: The purpose of our study was to evaluate the feasibility and treatment outcomes of recombinant adenovirus-p53 (rAd-p53, trademarked as Gendicine) combined with fractionated stereotactic radiotherapy (fSRT) in treatment of primary hepatocellular carcinoma (HCC).

Methods: We randomly enrolled 40 patients with HCC treated by fSRT alone (fSRT group) or rAd-p53 combined with fSRT (combined group). Tumor size was 2-5.2 cm (average 3.2 cm). We prescribed 50 Gy in 10 fractions at the 50%-80% isodose line of the planning target volume for 2 weeks in two groups. The combined group was treated with two intratumoral injections of rAd-p53 on day 1 and 8 while fSRT started on day 3. Tumor response was assessed after treatment using modified WHO criteria. The follow-up period was 11-44 months (median 35 months).

Results: The overall response rate of fSRT group was 70%, with 4 patients showing complete response (20%), 10 partial response (50%) and 6 stable disease (30%). Correspondingly the overall response rate of combined group was 85%, with 7 patients showing complete response (35%), 10 partial response (50%) and 3 stable disease (15%). The 1-year survival rates of fSRT group and combined group were 70.0% and 90.0%, respectively. The 1-year disease-free survival rates of fSRT group and combined group were 65% and 85%, respectively. These treatments were well tolerated, because grade 3 or 4 toxicity was not observed.

Conclusion: These results suggest that rAd-p53 combined with fSRT is a relatively safe and effective method for treating primary hepatocellular carcinoma compared with only fSRT. Thus, rAd-p53 combined with fractionated SRT may be preferred as a choice of local treatment for primary HCC when the patients are inoperable or when the patients refuse operation.