Phase I-II study of intraoperative radiation therapy (IORT) after radical prostatectomy for prostate cancer.
OBJECTIVE
Recent studies have suggested an alpha/beta ratio in prostate cancer of 1.5-3 Gy, which is lower than that assumed for late-responsive normal tissues. Therefore the administration of a single, intraoperative dose of irradiation should represent a convenient irradiation modality in prostate cancer.


METHODS
Between February 2002 and June 2004, 34 patients with localized prostate cancer with only one risk factor (Gleason score > or =7, Clinical Stage [cT] > or =2c, or prostate-specific antigen [PSA] of 11-20 ng/mL) and without clinical evidence of lymph node metastases were treated with radical prostatectomy (RP) and intraoperative radiotherapy on the tumor bed. A dose-finding procedure based on the Fibonacci method was employed. Dose levels of 16, 18, and 20 Gy were selected, which are biologically equivalent to total doses of about 60-80 Gy administered with conventional fractionation, using an alpha/beta ratio value of 3.


RESULTS
At a median follow-up of 41 months, 24 (71%) patients were alive with an undetectable PSA value. No patients died from disease, whereas 2 patients died from other malignancies. Locoregional failures were detected in 3 (9%) patients, 2 in the prostate bed and 1 in the common iliac node chain outside the radiation field. A PSA rise without local or distant disease was observed in 7 (21%) cases. The overall 3-year biochemical progression-free survival rate was 77.3%.


CONCLUSIONS
Our dose-finding study demonstrated the feasibility of intraoperative radiotherapy in prostate cancer also at the highest administered dose.
Saracino
Biancamaria
B
Department of Radiotherapy, Regina Elena Cancer Institute, Rome, Italy. saracino@ifo.it
Gallucci
Michele
M
De Carli
Piero
P
Soriani
Antonella
A
Papalia
Rocco
R
Marzi
Simona
S
Landoni
Valeria
V
Petrongari
Maria Grazia
MG
Arcangeli
Stefano
S
Forastiere
Ester
E
Sentinelli
Steno
S
Arcangeli
Giorgio
G
D000368:Aged; D005240:Feasibility Studies; D006801:Humans; D007430:Intraoperative Care; D008297:Male; D008875:Middle Aged; D009364:Neoplasm Recurrence, Local / Q000175:diagnosis / Q000517:prevention & control*; D011468:Prostatectomy; D011471:Prostatic Neoplasms / Q000532:radiotherapy* / Q000601:surgery*; D020266:Radiotherapy, Conformal; D016896:Treatment Outcome