Clinical outcomes and predictive value of chromogranin A (CgA) and pancreastatin (PcSt) in liver-directed therapies (LDTs) for well-differentiated metastatic neuroendocrine tumors.

Abstract

e14620 Background: LDTs have been shown to improve time to tumor progression and morbidity in metastatic neuroendocrine tumors (mNETs). CgA and PcSt are being used to predict and evaluate response to LDTs. Methods: Medical records of 42 mNET patients (pts) with hepatic metastases treated with either bland hepatic artery embolization (HAE), chemoembolization (HACE), or hepatic radioembolization (HRE) at the University of Iowa from 2001 to 2011 were analyzed. Time to progression (TTP) and overall survival (OS) were calculated using Kaplan-Meier analysis. PcSt and CgA were compared using a standardized mean Results: The tumors were located in the small bowel in 21 pts (50%), pancreas in 8 (19%), lung in 2 (5%), and other locations in 11 pts (26%). 13 pts had HAE, 17 had HACE and 12 had HRE. 20 pts had a second procedure with 6 receiving HRE, 9 HAE and 5 HACE. There was no significant difference in initial radiographic response among the three treatments (p = 0.082). TTP was similar between HRE (15.1 months) and HAE or HACE (HA(C)E) (19.6 months) (p= 0.968). There was a trend towards an increased TTP in pts receiving HACE (33.4 months), compared to HAE (12.1 months) or HRE (15.1 months) (p = 0.512). The overall survival for all pts from the first intervention was 41.9 months. There was no significant difference in symptom improvement among the treatment groups (p = 0.265). HRE and HA(C)E had no difference in post-therapy fever (p=0.236), vomiting (p=0.470), or abdominal pain (p=0.139). There was no difference between HA(C)E and HRE in pre-therapy CgA (p= 0.1913) or PcSt (p=0.983) nor was there a difference in post-therapy change of CgA (p=0.233) and PcSt (p=0.158). TTP did not correlate with the pre-therapy CgA (p=0.131) or PcSt (p=0.630) nor the change in the post-therapy CgA (p=0.299) or PcSt (p=0.208). Conclusions: There was no significant difference in TTP in patients treated with HRE compared to patients treated with HAE or HACE in this cohort. No single therapy was better than another in reducing symptoms. Baseline CgA and PcSt and post-therapy marker changes did not predict TTP and there was no difference in post-therapy marker changes based on treatment type.