Patients with liver tumors called hepatocellular carcinomas and who have few other treatment options are likely to benefit from proton beam radiation therapy, Japanese researchers report in the journal Cancer.

Lead investigator Dr. Masaharu Hata told Reuters Health: “Proton beam therapy was given safely and effectively to a wide spectrum of patients with hepatocellular carcinoma.”

Hata and colleagues at the University of Tsukuba took a look back at 21 patients with liver tumors for whom other treatment modalities were contraindicated or not feasible because of coexisting diseases such as severe cirrhosis, kidney failure, and severe heart disease.

Seven of the patients had multiple liver tumors. The median tumor diameter was 40 mm. No patients had regional or distant metastases.

At a median of 3.3 years after proton beam radiation, all but one of the tumors was controlled. At 5 years, the objective response rate was 81 percent and the primary site control rate was 93 percent.

Four of 11 patients who developed recurrent liver tumors had a second course of proton beam therapy, which controlled the tumors.

At 5 years, overall survival was 33 percent and cause-specific survival was 67 percent.

Proton beam therapy was well tolerated.

“The results suggested that this method was tolerable and effective,” concluded Hata, “even for patients who had severe coexisting diseases or unfavorable conditions for whom other treatment modalities were contraindicated or unfeasible.”

Cancer August 2006.