Use of Local 111In-Capromab Pendetide Scan Results to Predict Outcome After Salvage Radiotherapy for Prostate Cancer
Received 22 August 2007; received in revised form 4 October 2007; accepted 6 October 2007. published online 03 January 2008.
Purpose
The 111In-capromab pendetide scan (ProstaScint; Cytogen Corp., Princeton NJ) is approved by the Food and Drug Administration to evaluate increasing prostate-specific antigen (PSA) levels after radical prostatectomy. This study evaluated the role of prostate bed 111In-capromab pendetide scan findings to predict response to salvage radiotherapy (RT).
Methods and Materials
Forty patients who had PSA recurrence after radical prostatectomy and a 111In-capromab pendetide scan immediately before salvage prostate bed RT (median, 66 Gy) were identified from the Duke Prostate Center database. Patients with distant uptake of capromab pendetide or long-term androgen deprivation therapy were excluded. Median follow-up after salvage RT was 2.7 years. Patient demographic, clinical, and pathologic characteristics; PSA values; and 111In-capromab pendetide scan results were retrospectively analyzed. A PSA failure after salvage RT was defined as PSA level greater than 0.2 ng/ml. Data were combined with other published results in a secondary pooled analysis of 106 patients.
Results
111In-Capromab pendetide findings included 20 patients with negative scan results and 20 with locally positive scan results. Two-year progression-free survival rates were 60% for patients with a negative scan result and 74% for those with a locally positive scan result (p = 0.49). Combined analysis did not show a difference in outcome based on local 111In-capromab pendetide scan result.
Conclusion
For patients without distant signal detected by using 111In-capromab pendetide scan, patients with locally positive scan findings did not have statistically different progression-free survival than those with a negative scan result, suggesting that salvage RT may be successful in patients with either a locally positive or negative 111In-capromab pendetide scan result.
∗Department of Radiation Oncology, Duke University Medical Center, Durham, NC
†Duke Prostate Center, Duke University Medical Center, Durham, NC
‡Department of Surgery, Division of Urologic Surgery, Duke University Medical Center, Durham, NC
§Duke Cancer Center Biostatistics, Duke University Medical Center, Durham, NC
‖Department of Radiology, Duke University Medical Center, Durham, NC
¶Department of Radiation Oncology, Virginia Commonwealth University School of Medicine, Richmond, VA
Reprint requests to: Bridget F. Koontz, M.D., Department of Radiation Oncology, Duke University Medical Center, Box 3085, Durham, NC 27710. Tel: (919) 668-7342; Fax: (919) 668-7345
Presented in part at the 2007 American Society of Clinical Oncology Prostate Symposium, February 22–24, 2007, Orlando, FL.
Conflict of interest: T.J. Polascik is a funded investigator for Cytogen Corp. J.Moul is a paid lecturer and consultant for Cytogen.
ABSTRACT