BACKGROUND:Assessing the neuroendocrine (NE) pattern in castration-resistant prostate cancer (CRPC) may prove useful in selecting potential responders to target therapies such as somatostatin analogues.
The aim of this study was to define a panel of markers or examinations appropriate to characterize NE differentiation (NED).
METHODS: Forty-seven patients with CRPC underwent a systematic diagnostic attempt to characterize the NE phenotype using a plasma blood test for chromogranin A (CgA) and immunohistochemical staining of needle biopsy-obtained specimens (CgA, somatostatin receptor 2 [SSTR2], Ki-67, and androgen receptors). In a subgroup of 26 patients, somatostatin receptor scintigraphy using 111In-DTPA-d-Phe octreotide (octreotide scintigraphy; Octreoscan, Covidien, Hazelwood, MO) was also performed.
RESULTS: NED was found in 85.1% of patients (if serum CgA, tissular CgA, and tissular SSTR2 were considered separately: 54%, 67%, and 58%, respectively). Only 15% of the 26-patient subgroup had an abnormal octreotide scintigraphy result. Although p-CgA and t-CgA were associated with more aggressive disease with a worse prognosis, patients with positive tissular SSTR2 staining had longer overall survival (OS).
CONCLUSION: This systematic approach to explore the NED in a quite homogeneous group of patients with CRPC seems reproducible and appropriate. Further investigations are required to validate this panel and better characterize potential responders to targeted therapy.
Written by:
Matei DV, Renne G, Pimentel M, Sandri MT, Zorzino L, Botteri E, De Cicco C, Musi G, Brescia A, Mazzoleni F, Valeria T, Detti S, de Cobelli O. Are you the author?
Division of Urology, European Institute of Oncology, Milan, Italy.
Reference: Clin Genitourin Cancer. 2012 Mar 6. Epub ahead of print.
doi: 10.1016/j.clgc.2011.12.004
PubMed Abstract
PMID: 22401754
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