Blood plasma derived extracellular vesicles (BEVs): particle purification liquid chromatography (PPLC) and proteomic analysis reveals BEVs as a potential minimally invasive tool for predicting response to breast cancer treatment

PURPOSE

Circulating blood plasma derived extracellular vesicles (BEVs) containing proteins hold promise for their use as minimally invasive biomarkers for predicting response to cancer therapy. The main goal of this study was to establish the efficiency and utility of the particle purification liquid chromatography (PPLC) BEV isolation method and evaluate the role of BEVs in predicting breast cancer (BC) patient response to neoadjuvant chemotherapy (NAC).

METHODS

PPLC isolation was used to separate BEVs from non-EV contaminants and characterize BEVs from 17 BC patients scheduled to receive NAC. Using LC-MS/MS, we compared the proteome of PPLC-isolated BEVs from patients (n = 7) that achieved a pathological complete response (pCR) after NAC (responders [R]) to patients (n = 10) who did not achieve pCR (non-responders [NR]). Luminal MCF7 and basaloid MDA-MB-231 BC cells were treated with isolated BEVs and evaluated for metabolic activity by MTT assay.

RESULTS

NR had elevated BEV concentrations and negative zeta potential (ζ-potential) prior to receipt of NAC. Eight proteins were enriched in BEVs of NR. GP1BA (CD42b), PECAM-1 (CD31), CAPN1, HSPB1 (HSP27), and ANXA5 were validated using western blot. MTT assay revealed BEVs from R and NR patients increased metabolic activity of MCF7 and MDA-MB-231 BC cells and the magnitude was highest in MCF7s treated with NR BEVs.

CONCLUSION

PPLC-based EV isolation provides a preanalytical separation process for BEVs devoid of most contaminants. Our findings suggest that PPLC-isolated BEVs and the five associated proteins may be established as predictors of chemoresistance, and thus serve to identify NR to spare them the toxic effects of NAC.

Two fully automated data-driven 3D whole-breast segmentation strategies in MRI for MR-based breast density using image registration and U-Net with a focus on reproducibility

Presence of higher breast density (BD) and persistence over time are risk factors for breast cancer. A quantitatively accurate and highly reproducible BD measure that relies on precise and reproducible whole-breast segmentation is desirable. In this study, we aimed to develop a highly reproducible and accurate whole-breast segmentation algorithm for the generation of reproducible BD measures. Three datasets of volunteers from two clinical trials were included. Breast MR images were acquired on 3 T Siemens Biograph mMR, Prisma, and Skyra using 3D Cartesian six-echo GRE sequences with a fat-water separation technique. Two whole-breast segmentation strategies, utilizing image registration and 3D U-Net, were developed. Manual segmentation was performed. A task-based analysis was performed: a previously developed MR-based BD measure, MagDensity, was calculated and assessed using automated and manual segmentation. The mean squared error (MSE) and intraclass correlation coefficient (ICC) between MagDensity were evaluated using the manual segmentation as a reference. The test-retest reproducibility of MagDensity derived from different breast segmentation methods was assessed using the difference between the test and retest measures (Δ_2-1), MSE, and ICC. The results showed that MagDensity derived by the registration and deep learning segmentation methods exhibited high concordance with manual segmentation, with ICCs of 0.986 (95%CI: 0.974-0.993) and 0.983 (95%CI: 0.961-0.992), respectively. For test-retest analysis, MagDensity derived using the registration algorithm achieved the smallest MSE of 0.370 and highest ICC of 0.993 (95%CI: 0.982-0.997) when compared to other segmentation methods. In conclusion, the proposed registration and deep learning whole-breast segmentation methods are accurate and reliable for estimating BD. Both methods outperformed a previously developed algorithm and manual segmentation in the test-retest assessment, with the registration exhibiting superior performance for highly reproducible BD measurements.

Risk factors associated with skeletal-related events following discontinuation of denosumab treatment among patients with bone metastases from solid tumors: A real-world machine learning approach

•

This study investigated SRE risk factors after densomuab treatment discontinuation.

•

An unbiased machine learning approach was developed to evaluate >60 variables.

•

Prior SREs and short denosumab treatment duration were primary risk factors.

•

The results can guide denosumab persistence decisions and improve patient outcomes.

Background

Clinical practice guidelines recommend the use of bone-targeting agents for preventing skeletal-related events (SREs) among patients with bone metastases from solid tumors. The anti-RANKL monoclonal antibody denosumab is approved for the prevention of SREs in patients with bone metastases from solid tumors. However, real-world data are lacking on the impact of individual risk factors for SREs, specifically in the context of denosumab discontinuation.

Purpose

We aim to identify risk factors associated with SRE incidence following denosumab discontinuation using a machine learning approach to help profile patients at a higher risk of developing SREs following discontinuation of denosumab treatment.

Methods

Using the Optum PanTher Electronic Health Record repository, patients diagnosed with incident bone metastases from primary solid tumors between January 1, 2007, and September 1, 2019, were evaluated for inclusion in the study. Eligible patients received ≥ 2 consecutive 120 mg denosumab doses on a 4-week (± 14 days) schedule with a minimum follow-up of ≥ 1 year after the last denosumab dose, or an SRE occurring between days 84 and 365 after denosumab discontinuation. Extreme gradient boosting was used to develop an SRE risk prediction model evaluated on a test dataset. Multiple variables associated with patient demographics, comorbidities, laboratory values, treatments, and denosumab exposures were examined as potential factors for SRE risk using Shapley Additive Explanations (SHAP). Univariate analyses on risk factors with the highest importance from pooled and tumor-specific models were also conducted.

Results

A total of 1,414 adult cancer patients (breast: 40%, prostate: 30%, lung: 13%, other: 17%) were eligible, of whom 1,133 (80%) were assigned to model training and 281 (20%) to model evaluation. The median age at inclusion was 67 (range, 19–89) years with a median duration of denosumab treatment of 253 (range, 88–2,726) days; 490 (35%) patients experienced ≥ 1 SRE 83 days after denosumab discontinuation. Meaningful model performance was evaluated by an area under the receiver operating curve score of 77% and an F1 score of 62%; model precision was 60%, with 63% sensitivity and 78% specificity. SHAP identified several significant factors for the tumor-agnostic and tumor-specific models that predicted an increased SRE risk following denosumab discontinuation, including prior SREs, shorter denosumab treatment duration, ≥ 4 clinic visits per month with at least one hospitalization (all-cause) event from the baseline period up to discontinuation of denosumab, younger age at bone metastasis, shorter time to denosumab initiation from bone metastasis, and prostate cancer.

Conclusion

This analysis showed a higher cumulative number of SREs, prior SREs relative to denosumab initiation, a higher number of hospital visits, and a shorter denosumab treatment duration as significant factors that are associated with an increased SRE risk after discontinuation of denosumab, in both the tumor-agnostic and tumor-specific models. Our machine learning approach to SRE risk factor identification reinforces treatment guidance on the persistent use of denosumab and has the potential to help clinicians better assess a patient’s need to continue denosumab treatment and improve patient outcomes.

Sulindac Improves Stiffness and Quality of Life in Women Taking Aromatase Inhibitors for Breast Cancer

PURPOSE

To examine benefit of sulindac for relief of musculoskeletal symptoms (MSS) in patients stable on aromatase inhibitors (AIs).

METHODS

Sulindac was evaluated at 150 mg twice daily for effects on MSS at 3, 6, 9, and 12 months in 50 postmenopausal women stable on AI therapy for a median of 12.5 months for hormone receptor-positive breast cancer. A separate, non-randomized group of 50 similar patients was observed for change in MSS over 12 months. MSS severity was assessed using the Western Ontario and McMaster Universities Osteoarthritis (WOMAC) Index and Brief Pain Inventory Short Form (BPI-SF). The Functional Assessment of Cancer Therapy-General form (FACT-G) measured quality of life (QOL). Change in MSS and QOL across time was assessed in each group using linear mixed effects models.

RESULTS

Stiffness, not pain, was the main complaint at baseline. At 12 months, sulindac patients reported decreases (improvements) in mean (95% CI) Total WOMAC score [- 5.85 (- 9.73, - 1.96)] and WOMAC pain [- 5.40 (- 10.64, - 0 .18)], Stiffness [- 9.53 (- 14.98, - 4.08)] and Physical Function [- 5.61 (- 9.62, - 1.60)] subscales, but not BPI-SF worst pain. Among sulindac patients with higher baseline MSS severity, 35% experienced ≥ 50% improvement in Total WOMAC and Total FACT-G scores [6.18 (2.08, 10.27); P = 0.003]. For the observation group, MSS and QOL did not improve over 12 months, even among those with higher baseline MSS severity.

CONCLUSIONS

Sulindac may relieve MSS in AI patients, especially physical function and stiffness. Randomized controlled trials should further evaluate NSAIDs on AI-MSS and AI adherence.

TRIAL REGISTRATION NUMBER AND DATE OF REGISTRATION

NCT01761877, December, 2012.

Sulindac, a Nonselective NSAID, Reduces Breast Density in Postmenopausal Women with Breast Cancer Treated with Aromatase Inhibitors

PURPOSE

To evaluate the effect of sulindac, a nonselective anti-inflammatory drug (NSAID), for activity to reduce breast density (BD), a risk factor for breast cancer.

EXPERIMENTAL DESIGN

An open-label phase II study was conducted to test the effect of 12 months' daily sulindac at 150 mg twice daily on change in percent BD in postmenopausal hormone receptor-positive breast cancer patients on aromatase inhibitor (AI) therapy. Change in percent BD in the contralateral, unaffected breast was measured by noncontrast magnetic resonance imaging (MRI) and reported as change in MRI percent BD (MRPD). A nonrandomized patient population on AI therapy (observation group) with comparable baseline BD was also followed for 12 months. Changes in tissue collagen after 6 months of sulindac treatment were explored using second-harmonic generated microscopy in a subset of women in the sulindac group who agreed to repeat breast biopsy.

RESULTS

In 43 women who completed 1 year of sulindac (86% of those accrued), relative MRPD significantly decreased by 9.8% [95% confidence interval (CI), -14.6 to -4.7] at 12 months, an absolute decrease of -1.4% (95% CI, -2.5 to -0.3). A significant decrease in mean breast tissue collagen fiber straightness (P = 0.032), an investigational biomarker of tissue inflammation, was also observed. MRPD (relative or absolute) did not change in the AI-only observation group (N = 40).

CONCLUSIONS

This is the first study to indicate that the NSAID sulindac may reduce BD. Additional studies are needed to verify these findings and determine if prostaglandin E₂ inhibition by NSAIDs is important for BD or collagen modulation.

Phase III Randomized Trial of Bisphosphonates as Adjuvant Therapy in Breast Cancer: S0307

BACKGROUND

Adjuvant bisphosphonates, when given in a low-estrogen environment, can decrease breast cancer recurrence and death. Treatment guidelines include recommendations for adjuvant bisphosphonates in postmenopausal patients. SWOG/Alliance/Canadian Cancer Trials Group/ECOG-ACRIN/NRG Oncology study S0307 compared the efficacy of three bisphosphonates in early-stage breast cancer.

METHODS

Patients with stage I-III breast cancer were randomly assigned to 3 years of intravenous zoledronic acid, oral clodronate, or oral ibandronate. The primary endpoint was disease-free survival (DFS) with overall survival as a secondary outcome. All statistical tests were two-sided.

RESULTS

A total of 6097 patients enrolled. Median age was 52.7 years. Prior to being randomly assigned, 73.2% patients indicated preference for oral vs intravenous formulation. DFS did not differ across arms in a log-rank test (P = .49); 5-year DFS was 88.3% (zoledronic acid: 95% confidence interval [CI] = 86.9% to 89.6%), 87.6% (clodronate: 95% CI = 86.1% to 88.9%), and 87.4% (ibandronate: 95% CI = 85.6% to 88.9%). Additionally, 5-year overall survival did not differ between arms (log rank P = .50) and was 92.6% (zoledronic acid: 95% CI = 91.4% to 93.6%), 92.4% (clodronate: 95% CI = 91.2% to 93.5%), and 92.9% (ibandronate: 95% CI = 91.5% to 94.1%). Bone as first site of recurrence did not differ between arms (P = .93). Analyses based on age and tumor subtypes showed no treatment differences. Grade 3/4 toxicity was 8.8% (zoledronic acid), 8.3% (clodronate), and 10.5% (ibandronate). Osteonecrosis of the jaw was highest for zoledronic acid (1.26%) compared with clodronate (0.36%) and ibandronate (0.77%).

CONCLUSIONS

We found no evidence of differences in efficacy by type of bisphosphonate, either in overall analysis or subgroups. Despite an increased rate of osteonecrosis of the jaw with zoledronic acid, overall toxicity grade differed little across arms. Given that patients expressed preference for oral formulation, efforts to make oral agents available in the United States should be considered.

Oxylipins Correlate with Quality of Life in Women Taking Aromatase Inhibitors for Breast Cancer

The purpose of this study was to determine if oxylipins – oxygenated bioactive lipid metabolites of ω-3 and ω-6 fatty acids with varying roles in inflammation and pain – correlate with aromatase inhibitor-associated arthralgia (AIA) and quality of life (QOL) in early stage breast cancer (ESBC) patients. Methods: ESBC patients on AI therapy were enrolled to an open-label study of sulindac, a non-steroidal anti-inflammatory drug (NSAID), for 12 months (n = 47). Pre-intervention arthralgia and physical function were assessed using the Western Ontario and McMaster Universities Osteoarthritis (WOMAC) questionnaire, where higher scores indicate worse symptoms. The Functional Assessment of Cancer Therapy – General (FACT-G) questionnaire was used to assess QOL, where higher scores indicate better QOL. A total of 53 plasma oxylipins in plasma were quantified by mass spectrometry. Pearson's correlation was used to measure the association between pre-intervention oxylipin concentrations, arthralgias and QOL. Results: Prior to initiating sulindac, baseline levels of 17 oxylipins were found to be significantly correlated with QOL scales. This included inverse associations between QOL and seven pro-inflammatory products of ω-6 fatty acid metabolism. Notably, prostaglandin E2, the primary target of NSAIDs, was negatively correlated with Social Well-Being (rho = −0.30; P = 0.04). Conversely, resolvin D1, a potent anti-inflammatory lipid, was positively associated with Total FACT-G (rho = 0.31; P = 0.03) and Emotional Well-Being (rho = 0.37; P = 0.01). Two ω-3 metabolites with unknown mechanisms were correlated with both QOL and WOMAC; 19,20-DiHDPE was positively correlated with Total (rho = 0.34; P = 0.02) and Social FACT-G (rho = 0.32; P = 0.03), and inversely with Total WOMAC (rho = -0.303; P = 0.04) and Stiffness (rho = −0.32; P = 0.03); and 5(6)-DiHETE was inversely correlated with Social FACT-G (rho = −0.33; P = 0.02) and positively with Total WOMAC (rho = 0.31; P = 0.04). Conclusions: This is the first evidence that plasma oxylipin metabolites of ω-3/ω-6 fatty acids correlate with QOL and arthralgia symptoms in patients on AIs and suggests oxylipins as a potential novel target for improving QOL and adherence to AI therapy in patients with ESBC.

Abstract P1-11-22: Aromatase inhibitors are significantly better tolerated by early stage breast cancer patients 75 or older and with significantly lower early discontinuation rate

Introduction:

Breast cancer is the most common cancer in women. In postmenopausal women with early stage estrogen receptor positive breast cancer, aromatase inhibitors (AI) are a common treatment option. AI's are reported to lead to a high early discontinuation rate in younger post-menopausal women due to poor tolerance. The most common side effects reported to lead to early discontinuation are arthralgia, hot flashes, fatigue, and night sweats. The reported tolerance to AI therapy in women age 75 or older is not well documented. Our study looks at women, ages 75 and older, diagnosed with early stage breast cancer who were placed on adjuvant AI therapy and focuses on tolerability, incidence of common side effects, rate of treatment changes, and on discontinuation rates.

Objective:

This study evaluates the tolerability, treatment side effects and the discontinuation rate of AI in women over the age of 75 with early stage breast cancer.

Methods:

Our study is a retrospective chart review of 58 patients' ages 75 to 95 with early stage breast cancer treated with adjuvant AI. Charts of patients were reviewed and duration of treatment, patient reported side effects, treatment changes, and discontinuation rate were recorded.

Results:

Data analysis showed that 36/55 (65.5%) of patients did not report significant side effects to AI. 6/55 (10.9%) patients required therapy changes due to side effects. 5/6 required one treatment change and 1/6 required multiple treatment changes. In 5/6 therapy was changed to another AI. Only 2/55 (3.6%) of patients discontinued therapy. In both patients who discontinued AI, therapy was discontinued due to medical complications unrelated to AI therapy. Average time to discontinuation was 11 months. The most common reported side effects were arthralgia 9/55 (16.4%), fatigue 3/55 (5.5%), hot flashes 4/55 (7.3%), rash 3/55 (5.5%) and hair thinning 3/55 (5.5%). The most common reported side effect which led to treatment change was arthralgia 4/6 (66.7%). With a median follow up time of 24 months, breast cancer specific mortality was 1/55 (1.8%).

Reported Side Effects on AIn=55 patientsPatients who noted symptomsPatients who changed therapy due to symptomsFatigue30Arthralgia94Hot flashes40Rash31Vaginal dryness10Hair thinning31

Conclusion:

Our study evaluated the tolerance of AI in older women diagnosed with early stage breast cancer. 36/55 (65.5%) of elderly patients reported no significant side effects suggesting that AI's are well tolerated in this population and the known side effects are significantly less common than previously reported in a younger cohort in whom arthralgia as well as vasomotor symptoms affect as many as 30% of women. This improved tolerance led to a significantly lower early discontinuation rate than previously reported in the younger cohort: discontinuation rate of 3.6% by 24 months in the 75 or older population versus 20% by 24 months in the younger cohort of post-menopausal women treated with AI.

Reference:

1 Wagner, L.I., Zhao, F., Goss, P.E. et al. Breast Cancer Res Treat (2018) 169: 537. https://doi-org.proxy.library.stonybrook.edu/10.1007/s10549-018-4713-2

Citation Format: Chaudhry B, Baer L, Kudelka A, Cohen J, Stopeck AT. Aromatase inhibitors are significantly better tolerated by early stage breast cancer patients 75 or older and with significantly lower early discontinuation rate [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr P1-11-22.

Abstract P1-11-24: Aromatase inhibitors and bone health in women 75 and older treated for early stage breast cancer

Introduction:

Breast cancer is the most common cancer in women. In estrogen receptor positive breast cancers aromatase inhibitors (AI) are a common treatment option. AIs are associated with a reduction in bone mineral density, and patients with osteopenia at baseline have a higher risk of developing subsequent osteoporosis while on AI therapy. Women age 75 and older are a fast growing subset of breast cancer patients and commonly have osteopenia or osteoporosis at time of breast cancer diagnosis. Studies of long-term effects of AI on bone density in these older women who are at higher risk of osteoporosis and musculoskeletal events are lacking at this time.

Objective:

To evaluate the objective change in bone density in women over the age of 75 diagnosed with early stage breast cancer and treated with AI.

Methods:

A retrospective chart review of 49 patients ages 75 to 95 diagnosed with early stage breast cancer and treated with AI. Pretreatment DEXA scan results were recorded as well as prevalence of bone targeted therapy at the time of breast cancer diagnosis. Incidence of bone targeted therapy initiated subsequent to cancer diagnosis and changes in T score on follow up DEXA scans were collected as well. Incidence of musculoskeletal events and osteonecrosis of the jaw were recorded.

Results:

40/49 (81.6%) of study women were found to have osteopenia (23/49 [46.9%]) or osteoporosis (17/49 [34.7%]) on pre-treatment DEXA scans. Only 16/49 (32.7%) of patients were on bone-targeted treatment prior to breast cancer diagnosis. Of the patient with baseline osteoporosis, only 4/17 (23.5%) were on bone targeted treatment prior to breast cancer diagnosis. 25/49 (51%) of women were initiated on bone targeted therapy subsequent to breast cancer diagnosis and following review of pretreatment DEXA scan results. 5/49 (10.2%) of women were started on bisphosphonates and 7/49 (14.3%) were started on Denosumab. On the first subsequent DEXA scan at a median follow up of 2 years, 14/21(66.7%) of women were noted to have stable DEXA findings (defined as change in T score less than 0.5). 7/21 (33.3%) had a worsening T score on repeat DEXA. Of those patients with worsening T score, 3/7 (42.9%) changed categories (either from normal density to osteopenia or from osteopenia to osteoporosis. 3/49 (6%) of patients sustained a fracture while on AI therapy. There were no reported events of osteonecrosis of the jaw.

 Subsequent DEXA showing stabilitySubsequent DEXA showing worsening T scoreFractureBaseline Normal bone density1 (n=3)2 (n=3)1 (n=9)Baseline Osteopenia9 (n=12)3 (n=12)0 (n=12)Baseline Osteoporosis4 (n=6)2 (n=6)2 (n=17)

Conclusion:

Many elderly women are found to have osteopenia or osteoporosis at the time of breast cancer diagnosis and AI initiation. Most elderly patients had stable findings on subsequent bone density testing. Women with known osteoporosis initiated on bone-targeted therapy and AI did not have significant worsening in bone health. With appropriate treatment and monitoring elderly women with baseline decreased bone density can be treated safely with aromatase inhibitors.

Citation Format: Baer L, Chaudhry B, Kudelka A, Cohen J, Stopeck AT. Aromatase inhibitors and bone health in women 75 and older treated for early stage breast cancer [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr P1-11-24.

Reproducible automated breast density measure with no ionizing radiation using fat-water decomposition MRI

BACKGROUND

Increased breast density is a significant independent risk factor for breast cancer, and recent studies show that this risk is modifiable. Hence, breast density measures sensitive to small changes are desired.

PURPOSE

Utilizing fat-water decomposition MRI, we propose an automated, reproducible breast density measurement, which is nonionizing and directly comparable to mammographic density (MD).

STUDY TYPE

Retrospective study.

POPULATION

The study included two sample sets of breast cancer patients enrolled in a clinical trial, for concordance analysis with MD (40 patients) and reproducibility analysis (10 patients).

FIELD STRENGTH/SEQUENCE

The majority of MRI scans (59 scans) were performed with a 1.5T GE Signa scanner using radial IDEAL-GRASE sequence, while the remaining (seven scans) were performed with a 3T Siemens Skyra using 3D Cartesian 6-echo GRE sequence with a similar fat-water separation technique.

ASSESSMENT

After automated breast segmentation, breast density was calculated using FraGW, a new measure developed to reliably reflect the amount of fibroglandular tissue and total water content in the entire breast. Based on its concordance with MD, FraGW was calibrated to MR-based breast density (MRD) to be comparable to MD. A previous breast density measurement, Fra80-the ratio of breast voxels with <80% fat fraction-was also calculated for comparison with FraGW.

STATISTICAL TESTS

Pearson correlation was performed between MD (reference standard) and FraGW (and Fra80). Test-retest reproducibility of MRD was evaluated using the difference between test-retest measures (Δ_1-2 ) and intraclass correlation coefficient (ICC).

RESULTS

Both FraGW and Fra80 were strongly correlated with MD (Pearson ρ: 0.96 vs. 0.90, both P < 0.0001). MRD converted from FraGW showed higher test-retest reproducibility (Δ_1-2 variation: 1.1% ± 1.2%; ICC: 0.99) compared to MD itself (literature intrareader ICC ≤0.96) and Fra80.

DATA CONCLUSION

The proposed MRD is directly comparable with MD and highly reproducible, which enables the early detection of small breast density changes and treatment response.

LEVEL OF EVIDENCE

3 Technical Efficacy: Stage 1 J. Magn. Reson. Imaging 2018;48:971-981.

Abstract OT1-01-04: A phase 2, open-label study of imprime PGG (Imprime), a novel beta glucan, with pembrolizumab (Pembro) in chemotherapy-resistant metastatic triple negative breast cancer (TNBC)

By blocking the interaction of PD-L1 with PD-1, immune checkpoint inhibitors (CPI) can unleash specific, anti-cancer killing function of activated cytotoxic T cells in patients (pts) for whom there is evidence of an ongoing anti-cancer immune response (PD-L1 expression and/or activated T cells within the tumor bed). Single agent CPI therapy has provided substantial clinical benefit to pts with multiple cancer types. Though effective, response rates are typically limited (˜15-30% of pts depending on tumor type) and therapy fails to benefit the majority of pts. For these pts there is often limited or no evidence of an ongoing T cell-based immune response. Agents that stimulate the anti-cancer immune response may be particularly promising in expanding the clinical responsiveness to CPI therapies. Imprime is a novel beta glucan derived from Saccharomyces acting mechanistically as a pathogen-associated molecular pattern (PAMP) or non-self danger signal, to awaken and activate the innate immune system. Imprime drives a cascade of immune activating events activating tumor-specific cytotoxic T cells. Imprime treatment elicits repolarization of the immunosuppressive microenvironment while activating the maturation of antigen presenting cells. Imprime has significantly enhanced the efficacy of CPI therapy in preclinical tumor models. In humans, Imprime-mediated innate immune activation requires the formation of an immune complex with naturally-occurring anti-beta glucan antibodies (ABA). Formation of this complex is dependent upon sufficient ABA levels. Imprime is now being studied in combination with pembro (KEYTRUDA®), a humanized mAb against PD-1 which has been previously studied in TNBC pts.This phase 2 study explores the treatment combination in pts with metastatic TNBC who progressed following at least one line of chemotherapy and pts with metastatic melanoma who progressed following CPI therapy with sufficient pre-treatment ABA levels (˜50% of screened patients). The study is a Simon 2-stage design. Specific to the TNBC tumor type, a sample size of 12 pts in Stage 1 is planned. Criteria to advance to Stage 2 are ≤4 GR 3/4 AEs and ≥2 objective responses in TNBC. An additional 30 TNBC pts may be enrolled in Stage 2. Main eligibility criteria are metastatic TNBC after chemotherapy in the metastatic setting and serum ABA ≥20 µg/mL. The primary endpoints are ORR and safety; secondary endpoints are TTR, CRR, DoR, PFS, and OS. Efficacy will be analyzed for ORR and CRR as point estimates with 95% CI and for PFS, OS, DoR and TTR as descriptive summaries. Safety parameters will be summarized. Exploratory endpoints include ORR and PFS based on irRECIST. This study aims to collect pre- and early on-treatment tumor (6 wks post-1st dose) biopsies and peripheral blood to assess the impact of the treatment combination on immune activating events in the periphery and at the tumor site. As of June 2017, 11 sites were open and 4 pts were in treatment. The trial is sponsored by Biothera Pharmaceuticals, Inc. in collaboration with Merck & Co. (ClinicalTrials.gov NCT02981303) For information, contact Richard D. Huhn, MD, Biothera Med Dir at rhuhn@biothera.com or 651-256-4657.

Citation Format: O'Day SJ, Stopeck AT, Huhn RD, Gargano MA, Prathikanti R, Ma B, Mattson PM, Lowe JR, Bose N, Ertelt KE, Ottoson NC, Uhlik MT, Graff JR, Chisamore MJ. A phase 2, open-label study of imprime PGG (Imprime), a novel beta glucan, with pembrolizumab (Pembro) in chemotherapy-resistant metastatic triple negative breast cancer (TNBC) [abstract]. In: Proceedings of the 2017 San Antonio Breast Cancer Symposium; 2017 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2018;78(4 Suppl):Abstract nr OT1-01-04.

Transfer and Expression of the Interferon Gamma Gene in Human Endothelial Cells Inhibits Vascular Smooth Muscle Cell Growth in Vitro

Intimal hyperplasia in blood vessels is primarily caused by the migration and proliferation of vascular smooth muscle cells. Excessive intimal thickening characterizes atherosclerosis as well as bypass graft and angioplasty failures. Endothelial cell-smooth muscle cell interactions and local cytokine production are important regulators of smooth muscle cell growth. Interferon gamma (γ-IFN), a product of T lymphocytes found in atherosclerotic lesions, inhibits smooth muscle cell proliferation in vitro. To determine if local delivery of γ-IFN may be useful in the treatment or prevention of vascular proliferative diseases, we transferred the human γ-IFN gene into endothelial cells isolated from human arteries and microvessels using a retroviral vector. Biologically active γ-IFN was produced and secreted by γ-IFN transduced endothelial cells, but not by control, nontransduced cells, or cells identically transduced with E. coli beta galactosidase (β-gal). To more closely approximate the microenvironment of blood vessels, subconfluent smooth muscle cells were plated in coculture with control, nontransduced endothelial cells, γ-IFN transduced endothelial cells, or β-gal transduced endothelial cells. Smooth muscle cell growth was inhibited 30-70% by coculture with γ-IFN transduced endothelial cells compared to coculture with β-gal transduced or control endothelial cells (p < 0.05). Our results suggest endothelial cells modified to produce γ-IFN may be a useful therapy in proliferative vascular diseases. Copyright © 1997 Elsevier Science Inc.

Circulating Carbonic Anhydrase IX and Antiangiogenic Therapy in Breast Cancer

INTRODUCTION

Carbonic anhydrase IX (CAIX) is a hypoxia regulated metalloenzyme integral to maintaining cellular pH. Increased CAIX expression is associated with poor prognosis in breast cancer. To explore CAIX as a biomarker for breast cancer therapies, we measured plasma CAIX levels in healthy control subjects and in breast cancer patients.

METHODS

In control subjects we evaluated plasma CAIX stability via commercially available ELISA. We then similarly quantified plasma CAIX levels in (1) locally advanced breast cancer (LABC) patients treated with neoadjuvant paclitaxel + sunitinib (T + S) followed by doxorubicin and cyclophosphamide (AC); (2) metastatic breast cancer (MBC) patients treated with systemic chemotherapy.

RESULTS

Plasma CAIX levels were stable at room temperature for at least 48 hours in control subjects. Mean baseline plasma CAIX levels were lower in controls compared to patients with LABC or MBC. In LABC, CAIX levels rose significantly in response to administration of antiangiogenic therapy (T + S) (p = 0.02) but not AC (p = 0.37). In patients with MBC treated without an antiangiogenic agent CAIX levels did not change with therapy.

CONCLUSIONS

Our results suggest that CAIX may be an easily obtained, stable measure of tumor associated hypoxia as well as a useful pharmacodynamic biomarker for antiangiogenic therapy.

A maximum-likelihood method to estimate a single ADC value of lesions using diffusion MRI

PURPOSE

Design a statistically rigorous procedure to estimate a single apparent diffusion coefficient (ADC) of lesion from the mean lesion signal intensity in diffusion MRI.

THEORY AND METHODS

A rigorous maximum-likelihood technique that incorporated the statistics of the mean lesion intensity and accounted for lesion heterogeneity was derived to estimate the ADC value. Performance evaluation included comparison with the conventionally used linear-regression and a statistically rigorous state-of-the-art ADC-map technique using realistic and clinically relevant simulation studies conducted with assistance of patient data for homogeneous and heterogeneous lesion models.

RESULTS

The proposed technique outperformed the linear-regression and ADC-map approaches over a large spectrum of signal-to-noise ratio, ADC, lesion size, image-misalignment parameters, including at no image misalignment, and different amounts of lesion heterogeneity. The method was also superior at different sets of b values and in studies from specific patient-image-derived data. The technique took less than a second to execute.

CONCLUSIONS

A rigorous, computationally fast, easy-to-implement, and convenient-to-use maximum-likelihood technique was proposed to estimate a single ADC value of the lesion. Results provide strong evidence in support of the method. Magn Reson Med 76:1919-1931, 2016. © 2016 International Society for Magnetic Resonance in Medicine.

Safety of long-term denosumab therapy: results from the open label extension phase of two phase 3 studies in patients with metastatic breast and prostate cancer

Purpose

Zoledronic acid (ZA) or denosumab treatment reduces skeletal-related events; however, the safety of prolonged therapy has not been adequately studied. Here, we describe safety results of extended denosumab therapy in patients with bone metastases from the open-label extension phase of two phase 3 trials.

Methods

Patients with metastatic breast or prostate cancer received subcutaneous denosumab 120 mg Q4W or intravenous ZA 4 mg Q4W in a double-blinded fashion. Denosumab demonstrated superior efficacy in the blinded treatment phase; thus, patients were offered open-label denosumab for up to an additional 2 years.

Results

Cumulative median (Q1, Q3) denosumab exposure was 19.1 (9.2, 32.2) months in the breast cancer trial (n = 1019) and 12.0 (5.6, 21.3) months in the prostate cancer trial (n = 942); 295 patients received denosumab for >3 years. No new safety signals were identified during the open-label phase, or among patients who switched from ZA to denosumab. During the blinded treatment phase, exposure-adjusted subject incidences of osteonecrosis of the jaw (ONJ) were 49 (1.9 %) and 31 (1.2 %) in the denosumab and ZA groups, respectively. In total, 32 (6.9 %) and 25 (5.5 %) new cases of ONJ (not adjusted for exposure) were reported for patients continuing and switching to denosumab, respectively. The incidences of hypocalcemia were 4.3 and 3.1 %, in patients continuing and switching to denosumab, respectively.

Conclusion

These results describe the safety profile of denosumab after long-term exposure, or after switching to denosumab from ZA. No new safety signals were identified. Hypocalcemia rates were similar in the blinded treatment and open-label phases. ONJ rates increased with increasing exposure to antiresorptives, consistent with previous reports.

The role of denosumab in the prevention of hypercalcaemia of malignancy in cancer patients with metastatic bone disease

BACKGROUND

We compared the activity of denosumab with zoledronic acid for delaying or preventing hypercalcaemia of malignancy (HCM) in patients with advanced cancer and bone metastases or with multiple myeloma.

METHODS

Patient-level data were combined from two identically designed, randomised, double-blind, active-controlled, phase III trials of advanced cancer patients with breast cancer and other solid tumours (excluding breast or prostate cancer) or multiple myeloma. End-points included time to first on-study HCM, time to first and subsequent on-study HCM, proportion of patients experiencing HCM and proportion of patients experiencing recurrent HCM.

RESULTS

Denosumab significantly delayed the time to first on-study HCM, representing a 37% reduction in the hazard ratio (HR) compared with zoledronic acid (HR, 0.63; 95% confidence interval (CI): 0.41-0.98; P = 0.042) and reduced the risk of developing recurrent HCM (time to first and subsequent on-study HCM) by 52% (rate ratio, 0.48; 95% CI: 0.29-0.81; P = 0.006). The median time on study was 12.9 months. Fewer patients receiving denosumab compared with zoledronic acid experienced an HCM event (1.7% versus 2.7%; P = 0.028). Of the 84 patients experiencing an HCM event, 40% of those receiving zoledronic acid experienced >1 event of HCM compared with 31% of those receiving denosumab.

CONCLUSION

Denosumab treatment was more efficacious than treatment with zoledronic acid in delaying or preventing HCM in advanced cancer patients with breast cancer, other solid tumours or multiple myeloma.

Assessment of carbonic anhydrase IX expression and extracellular pH in B-cell lymphoma cell line models

The expression of carbonic anhydrase IX (CA IX) and its relationship to acidosis in lymphomas has not been widely studied. We investigated the protein expression of CA IX in a human B-cell lymphoma tissue microarray, and in Raji, Ramos and Granta 519 lymphoma cell lines and tumor models, while also investigating the relationship with hypoxia. An imaging method, acidoCEST magnetic resonance imaging (MRI), was used to estimate lymphoma xenograft extracellular pH (pHe). Our results showed that clinical lymphoma tissues and cell line models in vitro and in vivo had moderate CA IX expression. Although in vitro studies showed that CA IX expression was induced by hypoxia, in vivo studies did not show this correlation. Untreated lymphoma xenograft tumor pHe had acidic fractions, and an acidity score was qualitatively correlated with CA IX expression. Therefore, CA IX is expressed in B-cell lymphomas and is qualitatively correlated with extracellular acidosis in xenograft tumor models.

A phase I clinical trial of bavituximab and paclitaxel in patients with HER2 negative metastatic breast cancer

Bavituximab is a chimeric monoclonal antibody that targets phosphatidylserine (PS). PS is externalized on cells in the tumor microenvironment when exposed to hypoxia and/or other physiological stressors. On attaching to PS, bavituximab is thought to promote antitumor immunity through its effects on PS receptors in monocytes, and myeloid-derived suppressor cells, as well as trigger antitumor effects by inducing an antibody-dependent cellular cytotoxicity on tumor-associated endothelial cells. We conducted a phase I clinical trial of bavituximab in combination with paclitaxel in patients with HER2-negative metastatic breast cancer. Patients were treated with weekly paclitaxel (80 mg/m² for 3/4 weeks) and weekly bavituximab (3 mg/kg for 4/4 weeks). Correlative studies included the measurement of circulating microparticles, endothelial cells, and apoptotic tumor cells by flow cytometry. Fourteen patients with metastatic breast cancer were enrolled; all were evaluable for toxicity and 13 were evaluable for response. Treatment resulted in an overall response rate (RR) of 85% with a median progression-free survival (PFS) of 7.3 months. Bone pain, fatigue, headache, and neutropenia were the most common adverse effects. Infusion-related reactions were the most common adverse event related to bavituximab therapy. Correlative studies showed an increase in the PS-expressing apoptotic circulating tumor cells in response to bavituximab, but not with paclitaxel. No changes in the number of circulating endothelial cells or apoptotic endothelial cells were observed with therapy. Platelet and monocyte-derived microparticles decreased after initiation of bavituximab. Bavituximab in combination with paclitaxel is well tolerated for treatment of patients with metastatic breast cancer with promising results observed in terms of clinical RRs and PFS. The toxicity profile of bavituximab is notable for manageable infusion-related reactions with no evidence for increased thrombogenicity. Recent preclinical data suggest that bavituximab can also promote antitumor immune activity that should be explored in future clinical trials.

Abstract P1-12-03: Primary squamous cell carcinoma of the breast

BACKGROUND: Primary squamous cell carcinoma of the breast (PSCCB) is one of the rarest forms of breast cancer, accounting for less than 0.1% of all breast cancers. PSCCB can be aggressive with no typical radiologic findings on mammogram, often leading to delays in diagnoses or missed diagnoses. Previously reported cases of PSCCB have illustrated a wide range of clinical presentations, from an abnormal mammogram with no obvious breast mass to a breast abscess. In addition, due to the rarity of this disease, no clear consensus on definitive treatment or prognosis exists.

METHODS: Using a search of our pathology database, we identified females diagnosed with PSCCB at our institution from 2007-2012. Inclusion criteria included female patients over the age of 18 years old with a primary tumor consisting of &gt;90% malignant cells of squamous origin. Likewise, exclusion criteria included squamous cell cancer that had metastasized to the breast from elsewhere or lesions that were not independent of the overlying skin or nipple. We then performed a retrospective review to evaluate patient characteristics, presentation, tumor characteristics, treatment modalities and outcomes.

RESULTS: We identified three patients who were diagnosed with PSCCB during that timeframe. Their ages ranged from 35-65 years old, with two being post-menopausal and one pre-menopausal. Of the three, two were Caucasian and one was Hispanic. All three presented after self-palpating a breast mass. The average size of the mass seen on mammogram was 2.9 cm (range of 2.4 to 3.6 cm). Histologically, all three of the cancers were moderately to poorly differentiated. In addition, they all had a negative estrogen, progesterone, and HER2 receptor status with an elevated Ki-67. One patient was diagnosed at our institution but did not proceed to surgery and was lost to follow up. For the other two patients, one chose to undergo breast conservation with partial mastectomy and sentinel lymph node biopsy followed by whole breast radiation. The second patient proceeded with a total mastectomy and sentinel lymph node biopsy without radiation. There was no evidence of regional nodal disease in either patient at time of surgery. Furthermore, neither patient received any systemic therapy. Both patients were disease free at last follow up which was 5 and 11 months respectively.

CONCLUSION: Because PSCCB is so rare, prognosis and optimal treatment are still controversial. Most of the current literature portrays PSCCB as an aggressive cancer with a poor prognosis. This often leads to multimodality therapy consisting of mastectomy with axillary nodal clearance, adjuvant chemotherapy and radiation. In addition, locoregional and distant recurrences are common despite this aggressive treatment leading to the conclusion that PSCCB is relatively radioresistant with limited activity seen when using conventional breast cancer systemic therapies. Because treatment options can be limited, more research is needed to further elucidate the biological behavior of this rare cancer as well prognostic factors that may allow us to treat a patient more conservatively.

Citation Information: Cancer Res 2013;73(24 Suppl): Abstract nr P1-12-03.

Impact of denosumab on bone mass in cancer patients

Cancer therapy-induced bone loss (CTIBL) is a form of secondary osteoporosis associated with systemic chemotherapy and hormonal ablation therapy. The monitoring and treatment of CTIBL is an important component of comprehensive cancer care, especially for patients with curable disease and long life expectancies. Whereas oral bisphosphonates remain the most commonly used therapeutic option for CTIBL, additional treatment options may be required for patients who do not respond adequately or are intolerant to bisphosphonates, have renal insufficiency, or are receiving treatment with nephrotoxic medications. For these patients, denosumab, a monoclonal antibody targeting the receptor activator of nuclear factor-κB ligand (RANKL), offers an effective and well-tolerated alternative. Several recent randomized trials have examined the use of denosumab as treatment for CTIBL associated with hormone ablation therapy for breast and prostate cancer. Recent data suggest a possible role for RANKL inhibitors in both chemoprevention and the prevention of cancer recurrence through direct effects on breast tissue and breast cancer stem cells. The outcomes of several international Phase III clinical trials currently underway will help clarify the role of denosumab in patients undergoing cancer therapy.

Superiority of denosumab to zoledronic acid for prevention of skeletal-related events: a combined analysis of 3 pivotal, randomised, phase 3 trials

BACKGROUND

Patients with bone metastases from advanced cancer often experience skeletal-related events (SRE), which cause substantial pain and morbidity. Denosumab, a fully human monoclonal antibody that inhibits RANK Ligand (RANKL), is a novel bone-targeted agent with a distinct mechanism of action relative to the bisphosphonate zoledronic acid, for prevention of SRE. This pre-planned analysis evaluates the efficacy and safety of denosumab versus zoledronic acid across three pivotal studies.

METHODS

Patient-level data from three identically designed, randomised, double-blind, active-controlled, phase 3 trials of patients with breast cancer, prostate cancer, other solid tumours or multiple myeloma were combined. End-points included time to first SRE, time to first and subsequent (multiple) SRE, adverse events, time to disease progression and overall survival.

FINDINGS

Denosumab was superior to zoledronic acid in delaying time to first on-study SRE by a median 8.21months, reducing the risk of a first SRE by 17% (hazard ratio, 0.83 [95% confidence interval (CI): 0.76-0.90]; P<0.001). Efficacy was demonstrated for first and multiple events and across patient subgroups (prior SRE status; age). Disease progression and overall survival were similar between the treatments. In contrast to zoledronic acid, denosumab did not require monitoring or dose modification/withholding based on renal status, and was not associated with acute-phase reactions. Hypocalcaemia was more common for denosumab. Osteonecrosis of the jaw occurred at a similar rate (P=0.13).

CONCLUSION

Denosumab was superior to zoledronic acid in preventing SRE with favourable safety and convenience in patients with bone metastases from advanced cancer.

A phase II study of lapatinib and bevacizumab as treatment for HER2-overexpressing metastatic breast cancer

Preclinical data have demonstrated that the combination of antihuman epidermal growth factor receptor-2 (anti-HER2) and antivascular endothelial growth factor (anti-VEGF)--targeted agents has antitumor activity; these data indicate certain patients with HER2-overexpressing breast cancer may derive clinical benefit from this combination. The purpose of this single-arm phase II study was to determine the efficacy and safety of the dual-targeting combination of lapatinib and bevacizumab. Women with HER2-overexpressing advanced breast cancer received 1,500 mg oral lapatinib daily plus 10 mg/kg IV bevacizumab every 2 weeks. The primary endpoint was progression-free survival (PFS) at week 12; secondary endpoints included overall tumor response rate (ORR), clinical benefit rate (CBR), duration of response, time-to-response, PFS, and safety. Circulating tumor cells (CTC) and circulating endothelial cells (CEC) were measured at baseline and during study treatment as potential response markers. Fifty-two patients with stage IV disease were enrolled. The 12-week investigator-assessed PFS rate was 69.2% (95% confidence interval [CI]: 54.9, 81.3). Median PFS was 24.7 weeks (95% CI: 20.4, 35.1), and the CBR was 30.8% (95% CI: 18.7, 45.1). Of 45 patients with measurable disease, 6 were determined to have a partial response per Response Evaluation Criteria in Solid Tumors (ORR: 13.3%; 95% CI: 5.1, 26.8). The most common adverse events (AEs) included diarrhea, rash, and fatigue; most of these were either grade 1 or 2. Clinical responses were correlated with decreases in CTC and CEC. Lapatinib plus bevacizumab was active in patients with HER2-overexpressing breast cancer. The AE profile of the combination was consistent with the known profiles for these agents.

Task-based evaluation of segmentation algorithms for diffusion-weighted MRI without using a gold standard

In many studies, the estimation of the apparent diffusion coefficient (ADC) of lesions in visceral organs in diffusion-weighted (DW) magnetic resonance images requires an accurate lesion-segmentation algorithm. To evaluate these lesion-segmentation algorithms, region-overlap measures are used currently. However, the end task from the DW images is accurate ADC estimation, and the region-overlap measures do not evaluate the segmentation algorithms on this task. Moreover, these measures rely on the existence of gold-standard segmentation of the lesion, which is typically unavailable. In this paper, we study the problem of task-based evaluation of segmentation algorithms in DW imaging in the absence of a gold standard. We first show that using manual segmentations instead of gold-standard segmentations for this task-based evaluation is unreliable. We then propose a method to compare the segmentation algorithms that does not require gold-standard or manual segmentation results. The no-gold-standard method estimates the bias and the variance of the error between the true ADC values and the ADC values estimated using the automated segmentation algorithm. The method can be used to rank the segmentation algorithms on the basis of both the ensemble mean square error and precision. We also propose consistency checks for this evaluation technique.

The role of targeted therapy and biomarkers in breast cancer treatment

Breast cancer is the most prevalent life-threatening cancer in women and the second leading cause of cancer associated deaths. Consequently, optimizing breast cancer therapy to increase cure rates in early stage disease and improve life expectancy and palliation for patients with metastasis is a critical need and major area of research in medical oncology. This article focuses on the development of personalized therapy in breast cancer though the use of targeted therapies and their associated biomarkers. Topics reviewed include the historic advances in targeting the HER2 receptor and the current avenues being studied to circumvent resistance; new developments in the management of triple negative and metastatic breast cancer; and the challenges and pitfalls associated with targeting angiogenesis. Using these as examples, many of the innovations and challenges in the treatment of women with breast cancer are explored.

Prevalence of depression in adults with haemophilia

Multiple factors place adults with haemophilia at risk for depression. Health outcomes can be compromised in depressed patients secondary to increased risk taking behaviour and poor compliance with treatment recommendations. To assess the prevalence and risk factors associated with depression in adult patients with haemophilia treated at a haemophilia treatment centre. Adults with haemophilia were screened for depression during their annual clinic visit using the Patient Health Questionnaire 9 (PHQ-9), a validated tool for depression screening in adults. Depression was defined as a PHQ-9 score ≥ 5. Risk factors associated with depression were collected by chart review and correlated with depression scores. A total of 41 adult patients consented to the study and 37% met criteria for depression. Fifty-three per cent of patients with depression reported moderate to severe symptoms of depression (PHQ-9 score >10). Seventy-six per cent of patients with depression reported suffering functional impairment due to their depressive symptoms. Lack of social support and unemployment were significantly associated with higher PHQ-9 scores (P = 0.04 and P = 0.01 respectively). Adult patients with haemophilia have a high prevalence of depression. The addition of depression screening to the comprehensive care of adults with haemophilia may result in improved overall health outcomes and treatment adherence.

Incidence, risk factors, and outcomes of osteonecrosis of the jaw: integrated analysis from three blinded active-controlled phase III trials in cancer patients with bone metastases

BACKGROUND

Osteonecrosis of the jaw (ONJ) has been reported in patients receiving bisphosphonates for metastatic bone disease. ONJ incidence, risk factors, and outcomes were evaluated in a combined analysis of three phase III trials in patients with metastatic bone disease receiving antiresorptive therapies.

PATIENTS AND METHODS

Patients with bone metastases secondary to solid tumors or myeloma were randomly assigned to receive either s.c. denosumab (120 mg) or i.v. zoledronic acid (4 mg) every 4 weeks. On-study oral examinations were conducted by investigators at baseline and every 6 months. Oral adverse events were adjudicated by an independent blinded committee of dental experts.

RESULTS

Of 5723 patients enrolled, 89 (1.6%) patients were determined to have ONJ: 37 (1.3%) received zoledronic acid and 52 (1.8%) received denosumab (P = 0.13). Tooth extraction was reported for 61.8% of patients with ONJ. ONJ treatment was conservative in >95% of patients. As of October 2010, ONJ resolved in 36.0% of patients (29.7% for zoledronic acid and 40.4% for denosumab).

CONCLUSIONS

In this combined analysis of three prospective trials, ONJ was infrequent, management was mostly conservative, and healing occurred in over one-third of the patients. Educating physicians about oral health before and during bone-targeted therapy may help reduce ONJ incidence and improve outcomes.

Role of denosumab in the management of skeletal complications in patients with bone metastases from solid tumors

Skeletal-related events (SREs) including pain, fractures, and hypercalcemia are a major source of morbidity for cancer patients with bone metastases. The receptor activator of NF-κB ligand (RANKL) is a key mediator of osteoclast formation and activity in normal bone physiology as well as cancer-induced bone resorption. The first commercially available drug that specifically targets and inhibits the RANKL pathway is denosumab, a fully human monoclonal antibody that binds and neutralizes RANKL, thereby inhibiting osteoclast function. In this review, we summarize the major studies leading to the US Food and Drug Administration-approval of denosumab for the prevention of SREs in patients with bone metastases from solid tumors. Further, we discuss the role of denosumab in the prevention and treatment of SREs and bone loss in cancer patients. As a monoclonal antibody, denosumab has several advantages over bisphosphonates, including improved efficacy, better tolerability, and the convenience of administration by subcutaneous injection. In addition, as denosumab has no known renal toxicity, it may be the preferred choice over bisphosphonates in patients with baseline renal insufficiency or receiving nephrotoxic therapies. However, other toxicities, including osteonecrosis of the jaw and hypocalcemia, appear to be class effects of agents that potently inhibit osteoclast activity and are associated with both denosumab and bisphosphonate use. The data presented highlight the differences associated with intravenous bisphosphonate and denosumab use as well as confirm the essential role bone-modifying agents play in maintaining the quality of life for patients with bone metastases.

Phase I safety and pharmacokinetic study of bavituximab, a chimeric phosphatidylserine-targeting monoclonal antibody, in patients with advanced solid tumors

PURPOSE

Bavituximab is a chimeric immunoglobulin G1 phosphatidylserine-targeting monoclonal antibody that triggers vascular disruption and enhances antitumor immune response. This phase I study assessed the safety and pharmacokinetics of bavituximab in patients with advanced solid tumors.

EXPERIMENTAL DESIGN

Patients with refractory advanced solid tumors were enrolled into four sequential dose-escalation cohorts (0.1, 0.3, 1, or 3 mg/kg bavituximab weekly) with two dosing schedules. Patients in the 0.1 and 0.3 mg/kg cohorts received bavituximab on days 0, 28, 35, and 42. Patients in the 1 and 3 mg/kg cohorts were administered bavituximab on days 0, 7, 14, and 21. Safety, pharmacokinetics, and tumor response were assessed.

RESULTS

Twenty-six patients were accrued. No maximum tolerated dose was reached. Six serious adverse events occurred in five patients, including one pulmonary embolism at 3 mg/kg, which was the only dose-limiting toxicity (DLT) in the study. Bavituximab half-life ranged from 37 to 47 hours, with no accumulation seen following administration of multiple doses. Activated partial thromboplastin time was modestly prolonged in vitro at the highest dose tested. As assessed on day 56, a total of 18 patients were evaluable for efficacy, of whom 10 had disease progression and none had an objective response.

CONCLUSIONS

Bavituximab was well tolerated at doses ranging up to 3 mg/kg weekly. Pharmacokinetic studies support a weekly dosing regimen. Additional phase I and II clinical trials are in progress to investigate bavituximab in combination with chemotherapy and other molecularly targeted agents.

Randomized, Placebo-Controlled, Double-Blind, Phase II Study of Axitinib Plus Docetaxel Versus Docetaxel Plus Placebo in Patients With Metastatic Breast Cancer

Purpose

This multicenter, randomized, double-blind, phase II study assessed safety and efficacy of axitinib plus docetaxel in metastatic breast cancer (MBC).

Patients and Methods

Women with MBC were randomly assigned 2:1 to receive docetaxel 80 mg/m2 once every 3 weeks plus axitinib 5 mg twice per day (combination arm) or placebo (placebo arm), following a lead-in phase I trial. The primary end point was time to progression (TTP).

Results

In all, 168 patients were enrolled; 112 were randomly assigned to axitinib and 56 to placebo. Median TTP was numerically longer in the combination arm than in the placebo arm (8.1 v 7.1 months), but this difference was not statistically significant (hazard ratio, 1.24; 95% CI, 0.82 to 1.87; one-sided P = .156). The difference in median TTP was greatest among patients who had received prior adjuvant chemotherapy (9.2 v 7.0 months; P = .043, prespecified subgroup analysis). Objective response rate was higher in the combination arm (41.1% v 23.6%; P = .011). The most common grades 3 to 4 treatment-related adverse events (combination/placebo) included diarrhea (10.8%/0%), fatigue (10.8%/5.4%), stomatitis (12.6%/1.8%), mucositis (9.0%/0%), asthenia (7.2%/0%), and hypertension (4.5%/0%). Three patients in the combination arm experienced serious thromboembolic events (one death). Febrile neutropenia was more frequent in the combination arm (15.3% v 7.1%); rates of other hematologic toxicities were comparable. Increased toxicity with axitinib was generally managed by dose reduction and/or growth factor support.

Conclusion

The addition of axitinib to docetaxel did not improve TTP in first-line MBC treatment. Combination therapy may be more effective in patients previously exposed to adjuvant chemotherapy.

Changes in body weight and metabolic indexes in overweight breast cancer survivors enrolled in a randomized trial of low-fat vs. reduced carbohydrate diets

Overweight status is common among women breast cancer survivors and places them at greater risk for metabolic disorders, cardiovascular morbidity, and breast cancer recurrence than nonoverweight survivors. Efforts to promote weight control in this population are needed. The objective of this research was to evaluate the effect of low-fat or low-carbohydrate diet counseling on weight loss, body composition, and changes in metabolic indexes in overweight postmenopausal breast cancer survivors. Survivors (n = 40) were randomized to receive dietitian counseling for a low-fat or a reduced carbohydrate diet for 6 mo. Weight and metabolic measures, including glucose, insulin, HbA1c, HOMA, lipids, hsCRP, as well as blood pressure were measured at baseline, 6, 12 and 24 wk. Dietary intake of fat and carbohydrate was reduced by 24 and 76 g/day, respectively. Weight loss averaged 6.1 (± 4.8 kg) at 24 wk and was not significantly different by diet group; loss of lean mass was also demonstrated. All subjects demonstrated improvements in total/HDL cholesterol ratio, and significant reductions in HbA1c, insulin, and HOMA. Triglycerides levels were significantly reduced only in the low-carbohydrate diet group (-31.1 ± 36.6; P = 0.01). Significant improvements in weight and metabolic indexes can be demonstrated among overweight breast cancer survivors adherent to either a carbohydrate- or fat-restricted diet.

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&lt;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.

Denosumab compared with zoledronic acid for the treatment of bone metastases in patients with advanced breast cancer: a randomized, double-blind study

PURPOSE

This randomized study compared denosumab, a fully human monoclonal antibody against receptor activator of nuclear factor κ B (RANK) ligand, with zoledronic acid in delaying or preventing skeletal-related events (SREs) in patients with breast cancer with bone metastases.

PATIENTS AND METHODS

Patients were randomly assigned to receive either subcutaneous denosumab 120 mg and intravenous placebo (n = 1,026) or intravenous zoledronic acid 4 mg adjusted for creatinine clearance and subcutaneous placebo (n = 1,020) every 4 weeks. All patients were strongly recommended to take daily calcium and vitamin D supplements. The primary end point was time to first on-study SRE (defined as pathologic fracture, radiation or surgery to bone, or spinal cord compression).

RESULTS

Denosumab was superior to zoledronic acid in delaying time to first on-study SRE (hazard ratio, 0.82; 95% CI, 0.71 to 0.95; P = .01 superiority) and time to first and subsequent (multiple) on-study SREs (rate ratio, 0.77; 95% CI, 0.66 to 0.89; P = .001). Reduction in bone turnover markers was greater with denosumab. Overall survival, disease progression, and rates of adverse events (AEs) and serious AEs were similar between groups. An excess of renal AEs and acute-phase reactions occurred with zoledronic acid; hypocalcemia occurred more frequently with denosumab. Osteonecrosis of the jaw occurred infrequently (2.0%, denosumab; 1.4%, zoledronic acid; P = .39).

CONCLUSION

Denosumab was superior to zoledronic acid in delaying or preventing SREs in patients with breast cancer metastatic to bone and was generally well tolerated. With the convenience of a subcutaneous injection and no requirement for renal monitoring, denosumab represents a potential treatment option for patients with bone metastases.

Denosumab compared with zoledronic acid for the treatment of bone metastases in patients with advanced breast cancer: a randomized, double-blind study

PURPOSE

This randomized study compared denosumab, a fully human monoclonal antibody against receptor activator of nuclear factor κ B (RANK) ligand, with zoledronic acid in delaying or preventing skeletal-related events (SREs) in patients with breast cancer with bone metastases.

PATIENTS AND METHODS

Patients were randomly assigned to receive either subcutaneous denosumab 120 mg and intravenous placebo (n = 1,026) or intravenous zoledronic acid 4 mg adjusted for creatinine clearance and subcutaneous placebo (n = 1,020) every 4 weeks. All patients were strongly recommended to take daily calcium and vitamin D supplements. The primary end point was time to first on-study SRE (defined as pathologic fracture, radiation or surgery to bone, or spinal cord compression).

RESULTS

Denosumab was superior to zoledronic acid in delaying time to first on-study SRE (hazard ratio, 0.82; 95% CI, 0.71 to 0.95; P = .01 superiority) and time to first and subsequent (multiple) on-study SREs (rate ratio, 0.77; 95% CI, 0.66 to 0.89; P = .001). Reduction in bone turnover markers was greater with denosumab. Overall survival, disease progression, and rates of adverse events (AEs) and serious AEs were similar between groups. An excess of renal AEs and acute-phase reactions occurred with zoledronic acid; hypocalcemia occurred more frequently with denosumab. Osteonecrosis of the jaw occurred infrequently (2.0%, denosumab; 1.4%, zoledronic acid; P = .39).

CONCLUSION

Denosumab was superior to zoledronic acid in delaying or preventing SREs in patients with breast cancer metastatic to bone and was generally well tolerated. With the convenience of a subcutaneous injection and no requirement for renal monitoring, denosumab represents a potential treatment option for patients with bone metastases.

Caring for the breast cancer survivor: a guide for primary care physicians

Breast cancer accounts for more than 25% of cancers in women. Because of improved screening and treatment modalities, mortality has decreased significantly. Currently, over 2.5 million breast cancer survivors live in the US and receive care from a primary care provider. Providers need to be aware of common and serious complications of breast cancer treatment. In this review we discuss complications of local and systemic treatment for breast cancer, including lymphedema, osteoporosis, cardiovascular disease, and vasomotor symptoms. Current strategies for screening, monitoring, and treating these complications also are outlined.

A Clustering Algorithm for Liver Lesion Segmentation of Diffusion-Weighted MR Images

In diffusion-weighted magnetic resonance imaging, accurate segmentation of liver lesions in the diffusion-weighted images is required for computation of the apparent diffusion coefficient (ADC) of the lesion, the parameter that serves as an indicator of lesion response to therapy. However, the segmentation problem is challenging due to low SNR, fuzzy boundaries and speckle and motion artifacts. We propose a clustering algorithm that incorporates spatial information and a geometric constraint to solve this issue. We show that our algorithm provides improved accuracy compared to existing segmentation algorithms.

Sulindac and sulindac metabolites in nipple aspirate fluid and effect on drug targets in a phase I trial

Regular use of nonsteroidal anti-inflammatory drugs (NSAID) has been associated with reduced risk of breast cancer. Sulindac, a nonselective NSAID with both cyclooxygenase-2-dependent and -independent activities, is a candidate for breast chemoprevention. We conducted a phase Ib trial in 30 women at increased risk for breast cancer to evaluate the breast tissue distribution of sulindac at two dose levels (150 mg daily and 150 mg twice daily for 6 weeks), using nipple aspirate fluid (NAF) as a surrogate of breast tissue drug exposure. We also explored the effect of sulindac on drug-induced biomarkers in NAF. We show that sulindac and its metabolites partition to human breast as measured by NAF levels. Sulindac intervention did not decrease 13,14-dihydro-15-keto prostaglandin A(2), a stable derivative of prostaglandin E(2), in NAF, but exposure was associated with a significant trend towards higher levels of growth differentiation factor 15 in NAF in women receiving 150 mg twice daily (P = 0.038). These results are the first to show partitioning of sulindac and metabolites to human breast tissue and the first evidence for a potential dose-dependent effect of sulindac on growth differentiation factor 15 levels in NAF.

Evaluating segmentation algorithms for diffusion-weighted MR images: a task-based approach

Apparent Diffusion Coefficient (ADC) of lesions obtained from Diffusion Weighted Magnetic Resonance Imaging is an emerging biomarker for evaluating anti-cancer therapy response. To compute the lesion's ADC, accurate lesion segmentation must be performed. To quantitatively compare these lesion segmentation algorithms, standard methods are used currently. However, the end task from these images is accurate ADC estimation, and these standard methods don't evaluate the segmentation algorithms on this task-based measure. Moreover, standard methods rely on the highly unlikely scenario of there being perfectly manually segmented lesions. In this paper, we present two methods for quantitatively comparing segmentation algorithms on the above task-based measure; the first method compares them given good manual segmentations from a radiologist, the second compares them even in absence of good manual segmentations.

A phase II trial of single agent bevacizumab in patients with relapsed, aggressive non-Hodgkin lymphoma: Southwest oncology group study S0108

This is the first report of the Southwest oncology group phase II trial of single agent bevacizumab in patients with relapsed, aggressive non-Hodgkin lymphoma (NHL). Fifty-two patients in first or second relapse with diffuse large B-cell or mantle cell lymphoma were enrolled. Patients were treated with bevacizumab at 10 mg/kg every 2 weeks. Therapy was well tolerated with no unexpected toxicities observed. Six-month progression-free survival (PFS) was 16% with a response rate of 2% and median duration of response or stable disease of 5.2 months (range 3.5-72.7). Vascular endothelial growth factor A (VEGF) and VEGF receptor expression was observed in 70% and 65% of specimens, respectively. In an exploratory subgroup analysis, baseline urine VEGF and plasma vascular cell adhesion molecule-1 (VCAM) levels correlated with survival. Prolonged PFS in several patients as well as biomarker studies suggest the VEGF pathway plays an important role in aggressive NHL. Clinical trials combining active chemotherapy regimens with VEGF targeted agents are currently in progress.

A phase 1 trial of 2 dose schedules of ABT-510, an antiangiogenic, thrombospondin-1-mimetic peptide, in patients with advanced cancer

BACKGROUND

ABT-510 is a substituted nonapeptide that mimics the antiangiogenic activity of the endogenous protein thrombospondin-1 (TSP-1). The current study was designed to establish the safety of ABT-510 in the treatment of patients with advanced malignancies on a once-daily (QD) and twice-daily dosing schedule.

METHODS

Patients were randomly assigned to 1 of 6 dosing regimens: 20 mg, 50 mg, or 100 mg QD or 10 mg, 25 mg, or 50 mg twice daily. ABT-510 was administered by subcutaneous bolus injection in cycles of 28 days. Tumor response and disease progression were monitored at 8-week intervals by computed tomography scan or magnetic resonance imaging.

RESULTS

Thirty-six patients were randomly assigned in equal numbers to the 6 study regimens, with an additional 13 patients randomized to the 10-mg-twice-daily and 50-mg-twice-daily ABT-510 regimens. The expected pharmacokinetic target was achieved at all dose levels tested. The majority of adverse events were grade 1 or 2 (according to National Cancer Institute Common Toxicity Criteria [version 2]) and were not found to be dose related. The most frequently reported adverse events that were possibly related to ABT-510 included injection site reactions, asthenia, headache, and nausea. Grade 3 events considered to possibly be related included nausea, dyspnea, bone pain, constipation, vomiting, asthenia, and chills and tremors. One partial response was observed in a patient with carcinosarcoma who received 20 mg QD. The 6-month progression-free survival rate was 6%. Approximately 42% of patients (21 of 50 patients) had stable disease for > or =3 months.

CONCLUSIONS

ABT-510 can be administered at doses of 20 mg/day to 100 mg/day without significant toxicity. In the current study, minimal antitumor activity was observed, which was similar to observations in other single-agent antiangiogenic trials.

Combination of trastuzumab and tanespimycin (17-AAG, KOS-953) is safe and active in trastuzumab-refractory HER-2 overexpressing breast cancer: a phase I dose-escalation study

PURPOSE

This phase I study examined whether a heat shock protein (Hsp) 90 inhibitor tanespimycin (17-AAG; KOS-953) could be administered safely in combination with trastuzumab at a dose that inhibits Hsp90 function in vivo in lymphocytes.

PATIENTS AND METHODS

Patients with an advanced solid tumor progressing during standard therapy were eligible. Patients were treated with weekly trastuzumab followed by intravenous tanespimycin, assessed in escalating dose levels.

RESULTS

Twenty-five patients were enrolled onto four tanespimycin dose levels: 225 (n = 4), 300 (n = 3), 375 (n = 8), and 450 mg/m2 (n = 10). Dose-limiting toxicity (DLT) was observed at the third and fourth cohort (1 patient each): more than 2-week delay for grade 4 fatigue/grade 2 nausea and anorexia (375 mg/m2); more than 2-week delay for thrombocytopenia (450 mg/m2). Drug-related grade 3 toxicity included emesis, increased ALT, hypersensitivity reactions (two patients each), and drug-induced thrombocytopenia (n = 1). Common mild to moderate toxicities included fatigue, nausea, diarrhea, emesis, headache, rash/pruritus, increased AST/ALT, and anorexia. Pharmacokinetic analysis demonstrated no difference in tanespimycin kinetics with or without trastuzumab. Pharmacodynamic testing showed reactive induction of Hsp70 (a marker of Hsp90 inhibition) in lymphocytes at all dose levels. Antitumor activity was noted (partial response, n = 1; minor response, n = 4; stable disease > or = 4 months, n = 4). Tumor regressions were seen only in patients with human epidermal growth factor receptor 2 (HER-2)-positive metastatic breast cancer.

CONCLUSION

Tanespimycin plus trastuzumab is well tolerated and has antitumor activity in patients with HER-2+ breast cancer whose tumors have progressed during treatment with trastuzumab. These data suggest that Hsp90 function can be inhibited in vivo to a degree sufficient to cause inhibition of tumor growth.

Nelarabine induces complete remissions in adults with relapsed or refractory T-lineage acute lymphoblastic leukemia or lymphoblastic lymphoma: Cancer and Leukemia Group B study 19801

Nelarabine (506U78) is a soluble pro-drug of 9-beta-D-arabinofuranosylguanine (ara-G), a deoxyguanosine derivative. We treated 26 patients with T-cell acute lymphoblastic leukemia (T-ALL) and 13 with T-cell lymphoblastic lymphoma (T-LBL) with nelarabine. All patients were refractory to at least one multiagent regimen or had relapsed after achieving a complete remission. Nelarabine was administered on an alternate day schedule (days 1, 3, and 5) at 1.5 g/m(2)/day. Cycles were repeated every 22 days. The median age was 34 years (range, 16-66 years); 32 (82%) patients were male. The rate of complete remission was 31% (95% confidence interval [CI], 17%, 48%) and the overall response rate was 41% (95% CI, 26%, 58%). The principal toxicity was grade 3 or 4 neutropenia and thrombocytopenia, occurring in 37% and 26% of patients, respectively. There was only one grade 4 adverse event of the nervous system, which was a reversible depressed level of consciousness. The median disease-free survival (DFS) was 20 weeks (95% CI, 11, 56), and the median overall survival was 20 weeks (95% CI, 13, 36). The 1-year overall survival was 28% (95% CI, 15%, 43%). Nelarabine is well tolerated and has significant antitumor activity in relapsed or refractory T-ALL and T-LBL.