Radium-223 outcomes after multiple lines of metastatic castration-resistant prostate cancer therapy in clinical practice: Implication of pre-treatment spinal epidural disease Journal Article

  

Authors:	Spratt, D. E.; Osborne, J. R.; Zumsteg, Z. S.; Rebeiz, K.; Leeman, J.; Rivera, A.; Morris, M. J.; Zelefsky, M. J.
Article Title:	Radium-223 outcomes after multiple lines of metastatic castration-resistant prostate cancer therapy in clinical practice: Implication of pre-treatment spinal epidural disease
Abstract:	BACKGROUND: Magnetic resonance imaging (MRI) is not routinely performed before initiating radium-223 to document spinal epidural disease. However, radium-223 decays to form a-particles with very short path lengths that may not reach the epidural space. Herein, we investigate the impact of baseline spinal epidural disease on metastatic castration-resistant prostate cancer (mCRPC) patients treated with radium-223. METHODS: Between October 2013 to December 2014, 41 consecutive mCRPC patients at a large tertiary cancer center were prescribed radium-223 as part of standard of care. 29% of patients had pre-treatment epidural disease (posMRl), 27% had no epidural disease (negMRl), and 44% did not have a baseline MRI (noMRI). All patients had post-treatment spinal imaging. Actuarial survival times were calculated for overall survival (OS), spinal axis radiographic progression-free survival (spinePFS) and epidural progression-free survival (epiPFS) from time of first radium-223 treatment. RESULTS: For patients with posMRl (n =12), noMRI (n =18) and negMRl (n=11) cumulative rates of development or worsening of epidural disease and/or high-grade cord compression at time of last follow-up were 83%, 44% and 9%, respectively (P=0.001). For the posMRl, noMRI and negMRl groups the median OS was 6.3 months, 12.6 months and not reached (P=0.01), the median spinePFS was 3.2 months, 4.8 months and not reached (P=0.01), and the median epiPFS was 3.2 months, 10.4 months and not reached (P=0.001). Completing less than six cycles of radium-223 was significantly associated with worse OS (P < 0.0001), spinePFS (P=0.007) and epiPFS (P=0.01). Greater than or equal to twenty osseous lesions pre-treatment was significantly associated with worse spinePFS (P=0.001) and epiPFS (P=0.03). CONCLUSIONS: In a heavily pre-treated small cohort, patients with baseline epidural disease frequently progressed to spinal cord compression and early cessation of radium-223 therapy. Studies are needed to determine the optimal timing of radium-223 with other mCRPC therapies given the predilection for epidural disease and treatment failure after multiple prior lines of mCRPC therapy.
Keywords:	survival; radiation; trial; bone metastases
Journal Title:	Prostate Cancer and Prostatic Diseases
Volume:	19
Issue:	3
ISSN:	1365-7852
Publisher:	Nature Publishing Group
Date Published:	2016-09-01
Start Page:	271
End Page:	276
Language:	English
ACCESSION:	WOS:000381961100007
DOI:	10.1038/pcan.2016.14
PROVIDER:	wos
PUBMED:	27112529
Notes:	Article -- Source: Wos

https://synapse.mskcc.org/synapse/works/has_related_data_chk/98875