A randomized trial comparing hypofractionated and conventionally fractionated three-dimensional external-beam radiotherapy for localized prostate adenocarcinoma : a report on acute toxicity.
OBJECTIVE
To compare acute gastrointestinal (GI) and genitourinary (GU) toxicity between patient groups with localized prostate adenocarcinoma, treated with conventionally fractionated (CFRT) and hypofractionated (HFRT) three-dimensional conformal external-beam radiotherapy (3D-CRT).


METHODS
91 patients were enrolled into a randomized study with a minimum follow-up of 3 months. 44 men in the CFRT arm were irradiated with 74 Gy in 37 fractions at 2 Gy per fraction for 7.5 weeks. 47 men in the HFRT arm were treated with 57 Gy in 17 fractions for 3.5 weeks, given as 13 fractions of 3 Gy plus four fractions of 4.5 Gy. The clinical target volume (CTV) included the prostate and the base of seminal vesicles. The CTV-to-PTV (planning target volume) margin was 8-10 mm. Study patients had portal imaging and/or simulation performed on the first fractions and repeated at least weekly.


RESULTS
No acute grade 3 or 4 toxicities were observed. The grade 2 GU acute toxicity proportion was significantly lower in the HFRT arm: 19.1% versus 47.7% (chi(2)-test, p = 0.003). The grade 2 GU acute toxicity-free survival was significantly better in the HFRT arm (log-rank test, p = 0.008). The median duration of overall GI acute toxicity was shorter with HFRT: 3 compared to 6 weeks with CFRT (median test, p = 0.017).


CONCLUSIONS
In this first evaluation, the HFRT schedule is feasible and induces acceptable or even lower acute toxicity compared with the toxicities in the CFRT schedule. Extended follow-up is needed to justify this fractionation schedule's safety in the long term.
Norkus
Darius
D
Department of Radiotherapy, Institute of Oncology, Vilnius University, Vilnius, Lithuania. dnorkus@takas.lt
Miller
Albert
A
Kurtinaitis
Juozas
J
Haverkamp
Uwe
U
Popov
Sergey
S
Prott
Franz-Josef
FJ
Valuckas
Konstantinas Povilas
KP
D000230:Adenocarcinoma / Q000401:mortality / Q000473:pathology / Q000532:radiotherapy*; D000368:Aged; D014408:Biomarkers, Tumor / Q000097:blood; D018572:Disease-Free Survival; D019583:Dose Fractionation, Radiation; D005500:Follow-Up Studies; D041981:Gastrointestinal Tract / Q000528:radiation effects*; D006801:Humans; D053208:Kaplan-Meier Estimate; D008097:Lithuania; D008297:Male; D008875:Middle Aged; D009367:Neoplasm Staging; D011446:Prospective Studies; D011467:Prostate / Q000528:radiation effects; D017430:Prostate-Specific Antigen / Q000097:blood; D011471:Prostatic Neoplasms / Q000401:mortality / Q000473:pathology / Q000532:radiotherapy*; D011832:Radiation Injuries / Q000209:etiology*; D011879:Radiotherapy Dosage; D011880:Radiotherapy Planning, Computer-Assisted / Q000379:methods*; D020266:Radiotherapy, Conformal; D012007:Rectum / Q000528:radiation effects; D012669:Seminal Vesicles / Q000528:radiation effects; D001743:Urinary Bladder / Q000528:radiation effects; D014566:Urogenital System / Q000528:radiation effects*
D014408:Biomarkers, Tumor; D017430:Prostate-Specific Antigen