Single 4 Gy re-irradiation for painful bone metastasis following single fraction radiotherapy.
OBJECTIVE
to investigate effectiveness of a single-fraction of 4 Gy given for re-treatment of bone metastasis after previous single-fraction radiotherapy (RT).


METHODS
Of 135 patients retreated, 109 patients were retreated because of pain relapsing after 4 Gy (group I, n = 34), 6 Gy (group II, n = 39), or 8 Gy (group III, n = 36), while 26 patients were re-irradiated after initial non-response (group I, n = 12; group II, n = 8; group III, n = 6).


RESULTS
Of the 109 patients that were re-irradiated for pain relapse, 80 (74%) patients responded (complete response (CR) = 31%; partial response PR) = 42%). Among the 26 patients that initially did not respond, there were 12 (46%) responses. Patients with previous CR were more likely to achieve CR than were patients with previous PR (P = 0.042). No such finding was observed for obtaining PR, which was achieved in 45% each of patients previously having either CR or PR (P = 0.99). Patients with previous CR had similar chance to obtain either CR or PR (P = 0.65), while previous PR influenced subsequent response in the way of achieving more PRs than CRs (P = 0.00054). Combined, these data showed that patients with initial CR were more likely to respond than those with previous PR (85% vs. 67%, P = 0.037). There were no difference between the three initial treatment groups regarding the efficiency (CR or CR + PR) of second RT. Toxicity was low and only gastrointestinal.


CONCLUSIONS
Single-fraction RT consisting of 4 Gy was effective and little toxic treatment that could be administered after previous single-fraction RT.
Jeremic
B
B
Department of Oncology, University Hospital, Kragujevac, Yugoslavia.
Shibamoto
Y
Y
Igrutinovic
I
I
D000328:Adult; D000368:Aged; D001859:Bone Neoplasms / Q000150:complications / Q000532:radiotherapy* / Q000556:secondary*; D019583:Dose Fractionation, Radiation; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D010146:Pain / Q000209:etiology*; D010166:Palliative Care; D011879:Radiotherapy Dosage; D012008:Recurrence; D019233:Retreatment; D017211:Treatment Failure