title: Chromogranin A predicts outcome in prostate cancer patients treated with abiraterone.
abstract: In this retrospective study, we evaluated the chromogranin A (CgA) baseline value as a predictor of clinical outcome in patients with metastatic castration-resistant prostate cancer (CRPC) treated with abiraterone 1000 mg per day, whose disease progressed after docetaxel chemotherapy. In the 48 evaluable patients, serum CgA level was normal when <120  ng/ml (group A, n=16), within three times the upper normal value (UNV) when between 120 and 360 (group B, n=16), more than three times the UNV when ≥360  ng/ml (group C, n=16). Decline in PSA level ≥50% or more (PSA RR) was observed in 26 of 48 (54%) patients. PSA response rate did not correlate with the CgA groups. CgA levels more than three times the UNV predicted an early radiological progressive disease in eight of 11 cases (73%). The median progression-free survival (PFS) among the CgA groups A, B, and C was 9.2, 9.2, and 4.8 months respectively, P=0.0459. The median overall survival (OS) among the CgA groups was 19.0, 18.8, and 10.8 months respectively, P=0.2092. In the multivariate analysis, PSA RR (nonresponsive vs responsive) and CgA levels (group 3 vs groups 1+2) were predictors of PFS (P=0.0002 and P=0.0047 respectively), whereas PSA RR only was significantly associated with OS (P=0.0024), while CgA levels remained of borderline significance (P=0.0919). A serum CGA level more than three times the UNV predicted PFS and showed a trend vs OS prediction, independently from PSA response, in CRPC patients treated with abiraterone.
authors.affiliation: Medical Oncology Biostatistics and Clinical Trials, Istituto Scientifico Romagnolo per lo Studio e la Cura dei Tumori (I.R.S.T.) - IRCCS, Via Maroncelli 40, 47014 Meldola (FC), Italy.
authors.forename: Salvatore Luca
authors.initials: SL
authors.lastname: Burgio
authors.forename: Vincenza
authors.initials: V
authors.lastname: Conteduca
authors.forename: Cecilia
authors.initials: C
authors.lastname: Menna
authors.forename: Elisa
authors.initials: E
authors.lastname: Carretta
authors.forename: Lorena
authors.initials: L
authors.lastname: Rossi
authors.forename: Emanuela
authors.initials: E
authors.lastname: Bianchi
authors.forename: Barbara
authors.initials: B
authors.lastname: Kopf
authors.forename: Francesca
authors.initials: F
authors.lastname: Fabbri
authors.forename: Dino
authors.initials: D
authors.lastname: Amadori
authors.forename: Ugo
authors.initials: U
authors.lastname: De Giorgi
mesh_terms: D000230:Adenocarcinoma / Q000188:drug therapy* / Q000401:mortality / Q000556:secondary; D000368:Aged; D000369:Aged, 80 and over; D000736:Androstenes; D000737:Androstenols / Q000627:therapeutic use*; D014408:Biomarkers, Tumor / Q000097:blood*; D001859:Bone Neoplasms / Q000188:drug therapy* / Q000401:mortality / Q000556:secondary; D053379:Chromogranin A / Q000097:blood*; D004797:Enzyme-Linked Immunosorbent Assay; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008875:Middle Aged; D009367:Neoplasm Staging; D011379:Prognosis; D017430:Prostate-Specific Antigen / Q000097:blood; D011471:Prostatic Neoplasms / Q000188:drug therapy* / Q000401:mortality / Q000473:pathology; D064129:Prostatic Neoplasms, Castration-Resistant / Q000188:drug therapy* / Q000401:mortality / Q000556:secondary; D012189:Retrospective Studies; D015996:Survival Rate
chemical_list: D000736:Androstenes; D000737:Androstenols; D014408:Biomarkers, Tumor; D053379:Chromogranin A; D017430:Prostate-Specific Antigen; C089740:abiraterone
keywords: CRPC; CgA; PSA; abiraterone; bone flare; castration-resistant prostate cancer; chromogranin A