Elevation in multiple serum inflammatory biomarkers predicts survival of pancreatic cancer patients with inoperable disease

PURPOSE

Cancer-associated inflammation plays a driver role in pancreatic tumor development and progression. Moreover, recent studies have implicated the inflammatory tumor microenvironment in modulating therapy response and inducing resistance. The aim of this study is to investigate the prognostic and predictive value of the inflammatory biomarkers serum ferritin and C-reactive protein (CRP) in advanced pancreatic cancer patients.

METHODS

We measured pretreatment serum ferritin and CRP levels in 159 patients with inoperable pancreatic cancer participating in a phase III trial.

RESULTS

Serum ferritin and CRP levels were examined for correlations with overall survival using Kaplan-Meier analysis. When analyzed on a categorical basis, patients with higher ferritin (>median) or CRP (>25th percentile) had shorter overall survival. Moreover, the two biomarkers were not correlated suggesting independent mechanisms of production and release. However, when patients were evaluated by their ferritin and CRP levels, only patients with elevation in both inflammatory biomarkers showed a significant decrease in overall survival.

CONCLUSIONS

Serum ferritin and CRP are independent prognostic factors for shorter survival in patients with inoperable pancreatic tumors. Moreover, the evaluation of patients based on both biomarkers suggested that their prognostic value, although independent, reflected the broader state of cancer-associated inflammation. Thus, serum ferritin and CRP should be further explored as clinical biomarkers.

P5-14-11: Elevated Serum Ferritin Predicts Reduced Progression-Free and Overall Survival in Trastuzumab-Treated Metastatic Breast Cancer

Background: Approximately one-half of HER2−positive breast cancer patients will not respond to first-line trastuzumab-containing therapy. Since trastuzumab is now used in the HER2−positive adjuvant breast cancer setting, trastuzumab resistance will continue to be a vexing clinical problem, and better predictive and prognostic biomarkers are urgently needed.

One potential biomarker is serum ferritin. Although serum ferritin has been used as an indicator of total body iron, a specific functional role has not been proposed thus far other than perhaps recycling iron for erythropoiesis. Increased serum ferritin levels have been reported in breast cancer patients. However, the prevailing paradigm on ferritin at the time of these observations did not encourage speculation on its role or significance and was dismissed as a non-specific parameter for cellular damage. There are now multiple lines of evidence that have challenged this traditional paradigm and suggested ferritin to be a multi-functional factor involved in key cellular and systemic processes including immune regulation, angiogenesis, and iron delivery.

Methods: Pretreatment serum ferritin was measured using an ELISA assay in 66 metastatic breast cancer patients before starting first-line trastuzumab-containing therapy. Serum ferritin was determined using an ELISA from Assaypro, St. Charles, MO. Progression-free survival (PFS) and overall survival (OS) were analyzed using the Kaplan-Meier method and Cox modeling, with separate analyses as continuous serum ferritin, or as dichotomous categorical groups using the median pretreatment serum ferritin level as a cut off point. To interrogate a functional impact of elevated serum ferritin, we used a cell culture model.

Results: When analyzed as dichotomous categorical groups using the median pretreatment serum ferritin level as a cut off point, the elevated serum ferritin patient cohort had a significantly reduced OS (P<0.0001, median OS 12.73 vs. 69.57 months) and PFS (P=0.004, 8.30 vs. 23.90 months). In the cell culture model, ferritin bound to breast cancer cells promoted proliferation and activated AKT signaling. These novel observations suggest that the iron storage protein ferritin has a signaling role in tumor biology. Since the elevation in serum ferritin is unlikely a consequence of a change in total body iron, we also examined several possible sources for this elevation. Macrophages, but not breast cancer cells, were capable of ferritin secretion.

Conclusions: Elevated serum ferritin predicts reduced PFS and overall survival in metastatic breast cancer patients treated with first-line trastuzumab-containing therapy. The ability of ferritin to activate AKT signaling could underlie the trastuzumab resistance in patients. Therefore, serum ferritin may not only have predictive value as a clinical tool but also has direct functional significance in the treatment response, progression and survival of breast cancer patients.

Citation Information: Cancer Res 2011;71(24 Suppl):Abstract nr P5-14-11.

Abstract P6-14-09: Acute-Phase Reactions Following Treatment with Zoledronic Acid or Denosumab: Results from a Randomized, Controlled Phase 3 Study in Patients with Breast Cancer and Bone Metastases

Background: Intravenous (IV) bisphosphonates (BP) are currently used to treat bone metastases and prevent skeletal-related events (SRE) in patients with advanced breast cancer. In a phase 3 study, denosumab, a fully human monoclonal antibody against RANKL, was shown to be superior to zoledronic acid (ZA) in delaying or preventing SREs in patients with breast cancer and bone metastases. This prespecified analysis compares ZA and denosumab for the incidence of acute-phase reactions (flu-like syndrome including pyrexia, chills, flushing, bone pain, arthralgias, and myalgias) during the first 3 days after initial treatment in that study.

Methods: Eligible patients were randomized in a double-blind, double-dummy fashion to receive IV ZA 4 mg (adjusted for creatinine clearance as specified by the Zometa label) or subcutaneous denosumab 120 mg every 4 weeks. Most patients (99%) were women; mean (SD) age was 57 (12) years, and baseline characteristics were balanced between groups. Safety analyses were conducted in patients who received ≥1 dose of denosumab (N=1020) or ZA (N=1013). Patient records were searched for adverse events (AEs) and serious AEs that occurred during the first 3 days after the first administration of study drug, using 37 prespecified MedDRA 12.0 preferred terms potentially indicating acute-phase reactions. Per study protocol, AEs were considered serious if they were fatal, life-threatening, required or prolonged in-patient hospitalization, resulted in a persistent or significant disability, or were considered to present a significant medical hazard.

Results: AEs associated with acute-phase reactions in the first 3 days after treatment occurred in fewer patients in the denosumab group (10.4%) than in the ZA group (27.3%; P<0.0001), and no events were attributed to denosumab. The most common acute-phase reaction AEs included pyrexia (0.9% denosumab, 11.5% ZA), fatigue (2.4% denosumab, 4.0% ZA), bone pain (1.3% denosumab, 3.6% ZA), chills (0.3% denosumab, 3.6% ZA), and arthralgia (1.5% denosumab, 3.2% ZA). No patients (0%) in the denosumab group and 10 patients (1%) in the ZA group reported serious AEs associated with acute-phase reactions during the first 3 days. These events included pyrexia (n=7); bone pain (n=2); and asthenia, back pain, chest pain, chills, headache, and malaise (n=1 each). For 6 of the 10 patients, events of pyrexia, chest pain, chills, and bone pain were resolved within 4 days. Three patients with serious acute-phase reaction AEs discontinued ZA treatment after the first dose. Conclusion: Patients treated with denosumab experienced no serious AEs of acute-phase reaction and significantly fewer overall AEs of acute-phase reaction than patients receiving ZA.

Citation Information: Cancer Res 2010;70(24 Suppl):Abstract nr P6-14-09.

Frequency of zoledronic acid (ZOL) administration to prevent aromatase inhibitor-associated bone loss (AIBL)

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Background: Cancer patients (pts) are at increased risk of osteoporosis because of cancer treatment-induced bone loss. A hypogonadal state can increase bone resorption and turnover. Estrogen depletion with aromatase inhibitors (AIs), the preferred adjuvant treatment in postmenopausal women with early breast cancer (EBC), is associated with accelerated bone resorption and increased fracture risk. Several studies have demonstrated that IV ZOL can prevent AIBL in pts with EBC. ZOL to prevent AIBL was shown to be effective when administered every 6 mo in 4 large, randomized phase III trials. It is unknown if this is the optimal regimen. Methods: Pts who were receiving adjuvant breast cancer therapy with an AI and had a urinary N-telopeptide (uNTX) level > 50 nmol/mmol creatinine (Cr) and a bone density T-score < 1.5 at screening were treated with a single dose of ZOL 4 mg IV. Serum C-telopeptide (sCTX) and uNTX were obtained at baseline and then every 2 mo. Data are presently available from 10 pts who were followed for at least 6 mo and 1 pt followed for 2 mo after receiving ZOL. Wilcoxon signed-rank tests were performed for % change from baseline values. Results: Median baseline uNTX in these patients was 57.5 nmol/mmol Cr (range, 42.7 to 104.5). Median suppression of uNTX from baseline was 76.7% (range, 55.0% to 81.4%; P = .008) at 1 mo after therapy. At 6 mo, suppression of uNTX from baseline was 56.5% (range, 3.5% to 72.6%; P = .03). Similar significant suppression of sCTX up to 6 mo was observed. Continued suppression of uNTX and sCTX (approximately 50% decrease in median from baseline) was observed out to mo 12, although the number of pts studied is too small (n = 5 for uNTX and 4 for sCTX) to draw significant conclusions at this time. Pt accrual continues. Conclusions: A single dose of ZOL significantly suppressed bone resorption markers for at least 6 mo in pts receiving an adjuvant AI. It is not necessary to administer ZOL more frequently to prevent AIBL. These data suggest that ZOL administered every 6 mo is sufficient to prevent AIBL in this population. Further study will define whether this suppression of bone resorption markers continues for longer periods of time.

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