Acute urinary toxicity following transperineal prostate brachytherapy using a modified Quimby loading method.
OBJECTIVE
To examine the acute urinary toxicity following transperineal prostate implant using a modified Quimby loading method with regard to time course, severity, and factors that may be associated with a higher incidence of morbidity.


METHODS
One hundred thirty-nine patients with prostate adenocarcinoma treated with brachytherapy from 1997 through 1999 had follow-up records available for review. Patients considered for definitive brachytherapy alone included those with prostate specific antigen (PSA) < or = 6, Gleason score (GS) < or = 6, clinical stage < T2b, and prostate volumes generally less than 40 cc. Patients with larger prostate volumes were given neoadjuvant antiandrogen therapy. Those with GS > 6, PSA > 6, or Stage > T2a were treated with external beam radiation therapy followed by brachytherapy boost. Sources were loaded according to a modified Quimby method. At each follow-up, toxicity was graded based on a modified RTOG urinary toxicity scale.


RESULTS
Acute urinary toxicity occurred in 88%. Grade I toxicity was reported in 23%, grade II in 45%, and grade III in 20%, with 14% requiring prolonged (greater than 1 week) intermittent or indwelling catheterization. Overall median duration of symptoms was 12 months. There was no difference in duration of symptoms between patients treated with I-125 or Pd-103 sources (p = 0.71). After adjusting for GS and PSA, multivariate logistic regression analysis showed higher incidence of grade 3 toxicity in patients with larger prostate volumes (p = 0.002), and those with more seeds implanted (p < 0.001). Higher incidence of prolonged catheterization was found in patients receiving brachytherapy alone (p = 0.01), with larger prostate volumes (p = 0.01), and those with more seeds implanted (p < 0.001).


CONCLUSIONS
Interstitial brachytherapy for prostate cancer leads to a high incidence of acute urinary toxicity, most of which is mild to moderate in severity. A prolonged need for catheterization can occur in some patients. Patients receiving brachytherapy alone, those with prostate volumes greater than 30 cc, and those implanted with a greater number of seeds have the highest incidence of significant toxicity.
Kang
S K
SK
Department of Radiation Oncology, Duke University Medical Center, Durham, NC 27710, USA. kang@radonc.duke.edu
Chou
R H
RH
Dodge
R K
RK
Clough
R W
RW
Kang
H L
HL
Bowen
M G
MG
Steffey
B A
BA
Das
S K
SK
Zhou
S M
SM
Whitehurst
A W
AW
Buckley
N J
NJ
Kim
J H
JH
Joyner
R E
RE
Sarmina
I
I
Montana
G S
GS
Ingram
S S
SS
Anscher
M S
MS
D000208:Acute Disease; D000230:Adenocarcinoma / Q000097:blood / Q000532:radiotherapy*; D000328:Adult; D000368:Aged; D000704:Analysis of Variance; D001918:Brachytherapy / Q000009:adverse effects* / Q000379:methods; D005500:Follow-Up Studies; D006801:Humans; D007457:Iodine Radioisotopes / Q000627:therapeutic use; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D010165:Palladium / Q000627:therapeutic use; D017430:Prostate-Specific Antigen / Q000097:blood; D011471:Prostatic Neoplasms / Q000097:blood / Q000532:radiotherapy*; D011868:Radioisotopes / Q000627:therapeutic use; D014555:Urination Disorders / Q000209:etiology*
D007457:Iodine Radioisotopes; D011868:Radioisotopes; D010165:Palladium; D017430:Prostate-Specific Antigen