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Journal of Clinical Oncology, 2007 ASCO Annual Meeting Proceedings (Post-Meeting Edition).
Vol 25, No 18S (June 20 Supplement), 2007: 5065
© 2007 American Society of Clinical Oncology
Androgen receptor (AR) level in the prostatectomy specimen predicts time to disease progression post androgen suppression therapy
C. Cordon-Cardo,
M. J. Donovan,
F. Khan,
M. Teverovskiy,
S. Hamann,
S. Eggener,
A. Vicars and
P. Scardino
Columbia University, New York, NY; Aureon Laboratories Inc, Yonkers, NY; Memorial Sloan-Kettering Cancer Center, New York, NY
5065
Background: The androgen receptor (AR) plays an important role in the initiation and growth of prostate cancer and its subsequent response to hormone therapy. Previous analyses, including our own, have determined that elevated AR protein in the prostatectomy specimen is associated with progression of disease. We hypothesized that AR levels may also be predictive of response to androgen deprivation therapy (ADT) by evaluating time to castrate rise in PSA in patients treated with ADT at the time of a biochemical recurrence. By utilizing quantitative immunofluorescence (IF) and spectral imaging we evaluated AR content as an independent predictor of therapeutic outcome. Methods: 63 of 881 patients treated by radical prostatectomy had received ADT for a biochemical rise in PSA and or clinical progression of their disease. 32 of 63 patients had progressed post-ADT with a castrate rise in PSA. Tissue microarrays with triplicate patient cores were stained with a multiplex immunofluorescent assay (IF) which contained the nuclear marker DAPI, along with the following antibodies: Androgen Receptor (AR), Racemase (AMACR), CK18, HMWK and p63. IF images were acquired with spectral un-mixing employed to develop antibody-cell-specific gray scale images. Utilizing image analysis algorithms, quantitative features including intensity and area for selected antigens was generated. Results: Eleven IF antigen features were evaluated after feature selection and filtering using the concordance index with respect to outcome. A total of 5 features were statistically significant for predicting time to progression post therapy of which 2 features (AR intensity within AMACR (+) and (-) epithelial cells; p=0.0003 and p=0.0021, respectively) demonstrated that elevated levels of AR were associated with a shortened time to castrate rise in PSA post ADT. Clinical features alone were not found to be statistically significant with respect to predicting outcome. Conclusions: AR levels in the prostatectomy sample appears to be a useful indicator for determining therapeutic ADT response and potentially guiding future treatment decision and patient monitoring.
No significant financial relationships to disclose.
Abstract presentation from the 2007 ASCO Annual Meeting
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