Proton beam therapy for large hepatocellular carcinoma.
OBJECTIVE
To investigate the safety and efficacy of proton beam therapy (PBT) in patients with large hepatocellular carcinoma (HCC).


METHODS
Twenty-two patients with HCC larger than 10 cm were treated with proton beam therapy at our institution between 1985 and 2006. Twenty-one of the 22 patients were not surgical candidates because of advanced HCC, intercurrent disease, or old age. Median tumor size was 11 cm (range, 10-14 cm), and median clinical target volume was 567 cm(3) (range, 335-1,398 cm(3)). Hepatocellular carcinoma was solitary in 18 patients and multifocal in 4 patients. Tumor types were nodular and diffuse in 18 and 4 patients, respectively. Portal vein tumor thrombosis was present in 11 patients. Median total dose delivered was 72.6 GyE in 22 fractions (range, 47.3-89.1 GyE in 10-35 fractions).


RESULTS
The median follow-up period was 13.4 months (range, 1.5-85 months). Tumor control rate at 2 years was 87%. One-year overall and progression-free survival rates were 64% and 62%, respectively. Two-year overall and progression-free survival rates were 36% and 24%, respectively. The predominant tumor progression pattern was new hepatic tumor development outside the irradiated field. No late treatment-related toxicity of Grade 3 or higher was observed.


CONCLUSIONS
The Bragg peak properties of PBT allow for improved conformality of the treatment field. As such, large tumor volumes can be irradiated to high doses without significant dose exposure to surrounding normal tissue. Proton beam therapy therefore represents a promising modality for the treatment of large-volume HCC. Our study shows that PBT is an effective and safe method for the treatment of patients with large HCC.
Department of Radiation Oncology, Institute of Clinical Medicine, University of Tsukuba, Ibaraki, Japan. ssuga@pmrc.tsukuba.ac.jp
Shinji
S
Sugahara
Yoshiko
Y
Oshiro
Hidetsugu
H
Nakayama
Kuniaki
K
Fukuda
Masashi
M
Mizumoto
Masato
M
Abei
Junichi
J
Shoda
Yasushi
Y
Matsuzaki
Eriko
E
Thono
Mari
M
Tokita
Koji
K
Tsuboi
Koichi
K
Tokuuye
D000368:Aged; D000369:Aged, 80 and over; D006528:Carcinoma, Hepatocellular / Q000401:mortality / Q000473:pathology / Q000532:radiotherapy*; D019583:Dose Fractionation, Radiation; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008113:Liver Neoplasms / Q000401:mortality / Q000473:pathology / Q000532:radiotherapy*; D008297:Male; D008875:Middle Aged; D011169:Portal Vein; D061766:Proton Therapy; D011522:Protons / Q000009:adverse effects; D015996:Survival Rate; D013927:Thrombosis / Q000209:etiology
D011522:Protons