Proton irradiation in a single fraction for hepatocellular carcinoma patients with uncontrollable ascites. Technical considerations and results.
OBJECTIVE
To present technical considerations and results of proton irradiation in a single fraction for hepatocellular carcinoma (HCC) patients with uncontrollable ascites.


METHODS
Three HCC patients with uncontrollable ascites underwent proton irradiation of 24 Gy in a single fraction. Hepatic tumors were solitary in two patients, and multiple in one, and tumor sizes were 30, 30, and 33 mm in maximum diameter. No patient had lymph node or distant metastases. The center position of radiation fields was determined and the beam range was adjusted, using CT data taken immediately before irradiation to compensate for changes in the volume of ascites. Adjustment of the beam range was within 6 mm in water-equivalent thickness.


RESULTS
All irradiated tumors showed objective responses, and were controlled during the follow-up period. Of the three patients, two were alive with no evidence of disease at 13 and 30 months, respectively, after treatment. The remaining patient died of ruptured esophageal varices 6 months after treatment. No therapy-related toxicity of grade 3 or more was observed.


CONCLUSIONS
Proton beams were successfully adjusted immediately before irradiation. Single-dose irradiation with precisely adjusted proton beams may be tolerable for HCC patients with uncontrollable ascites.
Hata
Masaharu
M
Proton Medical Research Center, University of Tsukuba, Tsukuba, Ibaraki, Japan. mhata@syd.odn.ne.jp
Tokuuye
Koichi
K
Sugahara
Shinji
S
Tohno
Eriko
E
Fukumitsu
Nobuyoshi
N
Hashimoto
Takayuki
T
Ohnishi
Kayoko
K
Nemoto
Keiko
K
Ohara
Kiyoshi
K
Sakae
Takeji
T
Akine
Yasuyuki
Y
D000368:Aged; D001201:Ascites / Q000209:etiology / Q000517:prevention & control*; D006528:Carcinoma, Hepatocellular / Q000150:complications / Q000532:radiotherapy*; D019583:Dose Fractionation, Radiation; D005260:Female; D006801:Humans; D008113:Liver Neoplasms / Q000150:complications / Q000532:radiotherapy*; D008297:Male; D061766:Proton Therapy; D011882:Radiotherapy, High-Energy / Q000379:methods*; D055502:Secondary Prevention; D016896:Treatment Outcome; D011522:Protons
D011522:Protons