Biochemical disease-free survival rates following definitive low-dose-rate prostate brachytherapy with dose escalation to biologic target volumes identified with SPECT/CT capromab pendetide.
OBJECTIVE
To report biochemical disease-free survival (bDFS) after conformal brachytherapy with dose escalation to biological target volumes (BTVs) identified by Capromab Pendetide with single photon emission computed tomography and computed tomography image fusion (SPECT/CT).


METHODS
Two hundred thirty-nine (T1c-T3b NxM0) consecutive patients were evaluated by SPECT/CT before treatment. Intraprostatic SPECT/CT BTVs were identified and targeted for 150% dose escalation during brachytherapy seed implant (SI). Patients received either SI alone (n = 150) or external beam radiation therapy (EBRT) plus SI boost (EBRT+SI) (n = 89), with (n = 50) and without (n = 189) neoadjuvant hormone ablation therapy. Risk factors (RF) (prostate-specific antigen [PSA] >10 ng/mL, Stage > or = T2b, and Gleason grade > or = 7) defined risk group (RG) categories [none, 1, and > or = 2 RF define low, intermediate, and high RG] for bDFS calculations using four failure criteria: American Society for Therapeutic Radiology and Oncology (ASTRO) consensus definition, PSA >1.0 ng/mL (PSA >1), PSA >0.5 ng/mL after nadir (PSA >0.5), and PSA nadir+2 ng/mL rise in PSA clinical nadir (CN+2). Median followup was 47.2 months (range, 24.8-96.1).


RESULTS
Seven-year actuarial bDFS rates were 88.0%, 82.1%, 80.4%, and 79.9% using the ASTRO, PSA >1, PSA >0.5, and CN+2 failure criteria, respectively. ASTRO-defined bDFS rates were 96.0%, 87.0%, and 72.5% for low, intermediate, and high RG's.


CONCLUSIONS
The data presented here demonstrate the feasibility of performing SPECT/CT BTV dose escalation in a mature series.
Ellis
Rodney J
RJ
Department of Radiation Oncology, Aultman Hospital, Canton, OH, USA. rodney.ellis@case.edu
Zhou
Hang
H
Kim
Edward Y
EY
Fu
Pingfu
P
Kaminsky
Deborah A
DA
Sodee
Bruce
B
Colussi
Valdir
V
Vance
Waseet Z
WZ
Spirnak
John P
JP
Kim
Carolyn
C
Resnick
Martin I
MI
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000911:Antibodies, Monoclonal; D001918:Brachytherapy; D015331:Cohort Studies; D018572:Disease-Free Survival; D004307:Dose-Response Relationship, Radiation; D006801:Humans; D007457:Iodine Radioisotopes / Q000627:therapeutic use; D008297:Male; D008875:Middle Aged; D010165:Palladium / Q000627:therapeutic use; D011471:Prostatic Neoplasms / Q000000981:diagnostic imaging / Q000532:radiotherapy*; D011868:Radioisotopes / Q000627:therapeutic use; D019275:Radiopharmaceuticals; D020266:Radiotherapy, Conformal; D015899:Tomography, Emission-Computed, Single-Photon; D014057:Tomography, X-Ray Computed
D000911:Antibodies, Monoclonal; D007457:Iodine Radioisotopes; D011868:Radioisotopes; D019275:Radiopharmaceuticals; D010165:Palladium; C101315:Capromab Pendetide