Acute toxicity in high-risk prostate cancer patients treated with androgen suppression and hypofractionated intensity-modulated radiotherapy.
OBJECTIVE
To report acute toxicity resulting from radiotherapy (RT) dose escalation and hypofractionation using intensity-modulated RT (IMRT) treatment combined with androgen suppression in high-risk prostate cancer patients.


METHODS
Sixty patients with a histological diagnosis of high-risk prostatic adenocarcinoma (having either a clinical Stage of > or =T3a or an initial prostate-specific antigen [PSA] level of > or =20 ng/ml or a Gleason score of 8 to 10 or a combination of a PSA concentration of >15 ng/ml and a Gleason score of 7) were enrolled. RT prescription was 68 Gy in 25 fractions (2.72 Gy/fraction) over 5 weeks to the prostate and proximal seminal vesicles. The pelvic lymph nodes and distal seminal vesicles concurrently received 45 Gy in 25 fractions. The patients were treated with helical TomoTherapy-based IMRT and underwent daily megavoltage CT image-guided verification prior to each treatment. Acute toxicity scores were recorded weekly during RT and at 3 months post-RT, using Radiation Therapy Oncology Group acute toxicity scales.


RESULTS
All patients completed RT and follow up for 3 months. The maximum acute toxicity scores were as follows: 21 (35%) patients had Grade 2 gastrointestinal (GI) toxicity; 4 (6.67%) patients had Grade 3 genitourinary (GU) toxicity; and 30 (33.33%) patients had Grade 2 GU toxicity. These toxicity scores were reduced after RT; there were only 8 (13.6%) patients with Grade 1 GI toxicity, 11 (18.97%) with Grade 1 GU toxicity, and 5 (8.62%) with Grade 2 GU toxicity at 3 months follow up. Only the V60 to the rectum correlated with the GI toxicity.


CONCLUSIONS
Dose escalation using a hypofractionated schedule to the prostate with concurrent pelvic lymph node RT and long-term androgen suppression therapy is well tolerated acutely. Longer follow up for outcome and late toxicity is required.
Pervez
Nadeem
N
Division of Radiation Oncology, Cross Cancer Institute, Edmonton, Alberta, Canada. nadeempe@cancerboard.ab.ca
Small
Cormac
C
MacKenzie
Marc
M
Yee
Don
D
Parliament
Matthew
M
Ghosh
Sunita
S
Mihai
Alina
A
Amanie
John
J
Murtha
Albert
A
Field
Colin
C
Murray
David
D
Fallone
Gino
G
Pearcey
Robert
R
D000230:Adenocarcinoma / Q000097:blood / Q000188:drug therapy / Q000473:pathology / Q000532:radiotherapy*; D000368:Aged; D000369:Aged, 80 and over; D000726:Androgen Antagonists / Q000627:therapeutic use; D003131:Combined Modality Therapy; D019583:Dose Fractionation, Radiation; D041981:Gastrointestinal Tract / Q000528:radiation effects; D006801:Humans; D016729:Leuprolide / Q000627:therapeutic use; D015182:Lymphatic Irradiation / Q000009:adverse effects / Q000379:methods; D008297:Male; D008875:Middle Aged; D010388:Pelvis; D011446:Prospective Studies; D011467:Prostate / Q000528:radiation effects; D017430:Prostate-Specific Antigen / Q000097:blood; D011471:Prostatic Neoplasms / Q000097:blood / Q000188:drug therapy / Q000473:pathology / Q000532:radiotherapy*; D011832:Radiation Injuries / Q000473:pathology; D050397:Radiotherapy, Intensity-Modulated / Q000009:adverse effects* / Q000379:methods; D012007:Rectum / Q000528:radiation effects; D012669:Seminal Vesicles / Q000528:radiation effects; D001743:Urinary Bladder / Q000528:radiation effects; D014566:Urogenital System / Q000528:radiation effects
D000726:Androgen Antagonists; D017430:Prostate-Specific Antigen; D016729:Leuprolide