Postoperative External Irradiation of Patients with Primary Biliary Tract Cancer: A Multicenter Retrospective Study.
OBJECTIVE
The aim of the present study was to assess clinical outcomes of postoperative radiotherapy for biliary tract cancer patients.


METHODS
Clinical results of 187 patients treated with external irradiation in 31 Japanese Institutions between 2000 and 2011 were retrospectively analyzed. The median radiation dose was 50.4 Gy in fractions of 1.8-2 Gy.


RESULTS
Two-year actuarial overall survival and locoregional control (LCs) rates were 56% and 68%, respectively. In multivariate analysis, macroscopic residual tumor (R2) and irradiated doses <54 Gy were significant indicators of poor LC prognosis. For patients with complete resection (R0) or microscopic residual tumor (R1), 2-year LCs were 71% for <54 Gy and 83% for ≥54 Gy; doses ≥54 Gy were associated with high long-term LCs. There was no significant difference in acute adverse event rates between <54 Gy and ≥54 Gy.


CONCLUSIONS
Postoperative irradiation doses of approximately 54 Gy are safe and effective for R0 or R1 resection patients.
Department of Radiation Oncology, Osaka University Graduate School of Medicine, Osaka, Japan.
Kazuhiko
K
Hayashi
Department of Radiation Oncology, Osaka University Graduate School of Medicine, Osaka, Japan isohashi@radonc.med.osaka-u.ac.jp.
Fumiaki
F
Isohashi
Department of Radiation Oncology, Osaka University Graduate School of Medicine, Osaka, Japan.
Kazuhiko
K
Ogawa
Department of Radiology, Iwate Medical University, Iwate, Japan.
Hirobumi
H
Oikawa
Department of Radiology, University of Yamanashi, Yamanashi, Japan.
Hiroshi
H
Onishi
Department of Radiation Oncology, National Cancer Center Hospital, Tokyo, Japan.
Yoshinori
Y
Ito
Department of Radiology, Okayama University, Okayama, Japan.
Mitsuhiro
M
Takemoto
Department of Radiation Oncology, Tokyo Metropolitan Komagome Hospital, Tokyo, Japan.
Katsuyuki
K
Karasawa
Department of Radiation Oncology, Iwata City Hospital, Shizuoka, Japan.
Michiko
M
Imai
Department of Radiation Oncology, Kobe City Medical Center General Hospital, Hyogo, Japan.
Yasuhiro
Y
Kosaka
Department of Radiology, Kyoto Prefectural University of Medicine, Kyoto, Japan.
Hideya
H
Yamazaki
Department of Radiation Oncology, Osaka University Graduate School of Medicine, Osaka, Japan.
Yasuo
Y
Yoshioka
Department of Radiation Oncology, Yamagata University, Yamagata, Japan.
Kenji
K
Nemoto
Department of Radiation Oncology, Kinki University Faculty of Medicine, Osaka, Japan.
Yasumasa
Y
Nishimura
D000230:Adenocarcinoma / Q000401:mortality / Q000473:pathology / Q000532:radiotherapy* / Q000601:surgery; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001661:Biliary Tract Neoplasms / Q000401:mortality / Q000473:pathology / Q000532:radiotherapy* / Q000601:surgery; D002294:Carcinoma, Squamous Cell / Q000401:mortality / Q000473:pathology / Q000532:radiotherapy* / Q000601:surgery; D003131:Combined Modality Therapy; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008875:Middle Aged; D009364:Neoplasm Recurrence, Local / Q000401:mortality / Q000473:pathology / Q000532:radiotherapy* / Q000601:surgery; D009367:Neoplasm Staging; D018365:Neoplasm, Residual / Q000401:mortality / Q000473:pathology / Q000532:radiotherapy* / Q000601:surgery; D011184:Postoperative Period; D011379:Prognosis; D011879:Radiotherapy Dosage; D018714:Radiotherapy, Adjuvant; D012189:Retrospective Studies; D015996:Survival Rate
Postoperative radiotherapy; biliary tract cancer