A phase I study of neoadjuvant chemotherapy (NCT) with the gamma secretase (GS) inhibitor RO4929097 in combination with paclitaxel (P) and carboplatin (C) in women with triple-negative breast cancer (TNBC)

1043

Background: Notch receptors are overexpressed in TNBC. Notch activation involves the cleavage of Notch ligand/receptor complex by GS. RO4929097 (RO) is an oral inhibitor of GS. We are conducting a phase I NCT trial of intermittent RO in combination with P and C in TNBC to determine the dose limiting toxicity (DLT) and the maximum-tolerated dose (MTD) of RO. Because RO induces CYP3A4/5, plasma P and RO are quantified in real time to ensure P AUC exposure is not decreased. Methods: Women ≥ 18 years with clinical stage II/III TNBC received C AUC=6 on day 1 and weekly P 80 mg/m2 in combination with RO on days 1-3, 8-10 and 15-17 for six 21-day cycles. The starting dose of RO was 10 mg and escalated according to the 3+3 rule. DLT was defined as grade ≥3 (G3) non-hematologic toxicity (n-HT), grade 4 (G4) thrombocytopenia (TCP) or G4 neutropenia (NP) during cycle#1 (c1). Plasma specimens were analyzed for PK by a validated LC-MS/MS assay. Results: 13 pts were enrolled. Two pts enrolled at 10 mg RO with C AUC 6 developed G3,4 TCP during c1. The study was amended; the dose of C was decreased to AUC 5. No DLTs were observed with 10 mg RO and C AUC 5. Only 1 DLT ( G3 HTN) occured with 20 mg RO, but all 4 pts enrolled on this cohort required dose reductions of RO during subsequent cycles. The RO dose was de-escalated to 10 mg, additional 3 pts were treated with 10 mg RO. G≥3 HT included: G4 NP in 2 pts, G4 TCP in 1 pt, G3 NP in 6 pts, G3 anemia in 4 pts and G3 TCP in 5 pts. G≥3 n-HT included: G3 sensory neuropathy in 3 pts. G3 HTN, G3 fatigue and G3 depression occured in 1 pt each. There were no hospitalizations for treatment-related toxicities. PK studies indicate that P AUC ranged from 80% to 134% on week 3 compared to week 1. Ten pts completed 6 cycles of NCT, 3 are still receiving NCT. Five of 10 (50%) pts had complete pathologic response (pCR) in breast and axilla and 3 (30%) pts had minimal residual cancer in breast. Conclusions: The MTD of intermittent RO administered in combination with P and C is 10 mg. This MTD does not result in decreased P exposures. The pCR (50%) and minimal residual disease (30%) suggests this regimen is active in TNBC. Supported by the NCI/NIH Award Number U01CA076576. Clinical trial information: NCT01238133.

NCI 8609: Interim fluoro-3’-deoxythymidine (FLT) PET imaging findings from the phase I trial of PARP inhibitor veliparib (V) and carboplatin (C) in advanced breast cancer

1023

Background: We are currently conducting a phase I trial of PARP inhibitor, V on an intermittent (7 or 14 day) or continuous (21 day) schedule in combination with C in patients (pts) with advanced breast cancer. We are using FLT PET/CT sequentially to assess DNA damage induced by varying dose schedules of PARP inhibitor, where uptake of FLT depends on the proliferation rate of the tumor. Methods: Eligible pts received C-AUC 5 Q 3weeks (except dose level 1-AUC 6) plus escalating doses of V, BID on 7, 14, or 21-day schedules based on a standard 3+3 dose escalation design. We performed FLT PET/CT at baseline, cycle 1 day 7 and 14 and after cycle 3. Lesions were track-matched with the FDG PET/CT and semi-quantitatively assessed using 2D ROI placement in a matched, blinded fashion. Results: 38 pts have been accrued to 7 dose levels and FLT-PET imaging was successfully obtained in all pts with the proliferative whole body mapping revealing expected bone-marrow, liver and RESuptake. FLT-PET uptake showed a significant (p < 0.001) decrease between baseline and day 7 (N = 25) with an overall trend to rebound nearly to baseline at day 14 for pts that did not show a significant decrease in FLT uptake reduction after cycle 3. The 14-day (n = 15) dosing schedule resulted in more pronounced day 14 reduction in FLT uptake when compared to those on the 7-day (n = 7) schedule. A FLT rebound to baseline level appeared to be associated with limited therapy response. There were no reported toxicities from FLT imaging. Conclusions: FLT-PET was consistently obtained with excellent whole body quality. All lesions revealed a FLT (proliferation) uptake that was different from the FDG (metabolism) uptake. FLT uptake indicated an initial reduction of proliferation at day 7, followed by a rebound at day 21 in all patients on the 7 or 14 day schema. The trial protocol was therefore amended to include a 21 day schema which is currently still ongoing. FLT appears to be a promising in-vivo imaging marker that may serve as a guiding tool to optimize dosing schema in addition to assessing/ predicting overall response. Study support- U01 CA076576 /Wright Center of Innovation ODSA TECH09-028. Clinical trial information: NCT01251874.

Docetaxel-induced skin toxicities in breast cancer patients subsequent to paclitaxel shortage: a case series and literature review

PURPOSE

As the result of a recent national shortage in paclitaxel, some patients who were receiving or scheduled to receive weekly paclitaxel were converted to every 3-week (q3w) docetaxel with granulocyte colony-stimulating factor support. Our institution noted higher than expected incidence of severe skin toxicity events attributable to docetaxel during the shortage period among our breast cancer patients. In this report, we summarize the clinical course of the first five cases, review the literature surrounding docetaxel-induced skin toxicity, and offer possible prevention and treatment strategies to improve docetaxel tolerability.

METHODS

The observation period for this case series was August 1 through October 21, 2011. All patients treated with docetaxel were identified from our electronic medical record. Operable stage I-III breast cancer patients who received ≥ 1 dose of docetaxel monotherapy at 75-100 mg/m(2) q3w were included in this study. The cases of grade 3-4 docetaxel-induced skin toxicities identified by the treating oncologists were then contacted and signed an informed consent through an Institutional Review Board-approved protocol.

RESULTS

Thirty-four patients met the inclusion criteria. Five patients (14.7 %) experienced grade 3 skin toxicity events attributable to docetaxel, a significantly higher rate than previously reported for docetaxel dosed at 75-100 mg/m(2).

CONCLUSIONS

Docetaxel-induced dermatologic toxicity is well characterized; nonetheless, its etiology is largely unknown and evidence-based prevention and management strategies are lacking. This report shows that the use of docetaxel 75-100 mg/m(2) q3w subsequent to dose-dense doxorubicin and cyclophosphamide regimen can lead to unacceptable rate of severe skin toxicity.

Severe and prolonged lymphopenia observed in patients treated with bendamustine and erlotinib for metastatic triple negative breast cancer

PURPOSE

Triple negative breast cancers (TNBC) frequently have high epidermal growth factor receptor (EGFR) expression and are sensitive to DNA-damaging agents. Improved therapies are needed for this aggressive malignancy.

PATIENTS AND METHODS

We performed a phase I trial of bendamustine and erlotinib, an EGFR tyrosine kinase inhibitor, in patients with metastatic TNBC, ECOG performance status ≤2, and ≤1 prior chemotherapy for metastatic disease. Each 28-day cycle included intravenous bendamustine on days 1, 2 and oral erlotinib on days 5-21 with dose escalation according to a 3 + 3 phase I study design. Dose-limiting toxicity (DLT) was determined by toxicities related to study therapy observed during cycle 1.

RESULTS

Eleven patients were treated, 5 on dose level 1 and 6 on dose level 2. One patient had DLT on dose level 2. However, cumulative toxicities were observed, including grade 3/4 lymphopenia in 91 % (95 % CI 0.59-0.998) with progressively decreased CD4 counts and grade ≥3 infections in 36 % (95 % CI 0.11-0.69) of patients.

CONCLUSIONS

Combination therapy with bendamustine and erlotinib causes excessive toxicity with severe, prolonged lymphopenia, depressed CD4 counts, and opportunistic infections and should not be pursued further. Future trials of bendamustine combinations in TNBC patients should account for potential cumulative lymphocyte toxicity necessitating patient monitoring during and after treatment.

Abstract P2-11-07: Endothelial progenitor cells as novel markers of anthracycline induced cardiac injury

Background: Anthracyclines including doxorubicin (DOX) cause myocardial damage that manifests as either subclinical decrements of left ventricular ejection function (LVEF) or overt cardiomyopathy. LVEF changes and cardiac risk factors are insufficient predictors of future DOX cardiotoxicity. Bone marrow derived endothelial progenitor cells (EPCs) are mobilized and are homed to sites of myocardial injury to help with repair of damaged myocardium. We hypothesized that EPC levels would be indicative of early DOX cardiotoxicity. Hence, we prospectively collected serial blood samples to evaluate functional EPCs, Troponin I (Ti) and B-natriuretic peptide (BNP), in patients (pts) receiving DOX-based chemotherapy.

Methods: Eligible pts were initiating adjuvant DOX for early stage breast cancer. Pts underwent cardiac magnetic resonance (CMR), Ti, BNP, and EPC at baseline, after 1 cycle of DOX, and after completion of DOX. CD133+ progenitor cells were isolated from the peripheral blood mononuclear cells (PBMC) using AutoMACS (automated magnetic cell sorting, Miltenyi Biotech). In vitro colony forming unit (CFU) assay was performed for isolated CD133+ progenitor cells on MethoCult (Stemcell Technology). After 8 days of culture, EPC colonies were counted using a two-step image analysis algorithm. Repeated measures analysis of variance modeled changes in cardiac markers over time. Logistic regression was used to correlate variables with abnormal Ti.

Results: Forty two women were enrolled. The average age was 52 years (range 33–68) and stage distribution was I (14%), II (58%) and III (28%). All but one patient received peg-fligrastim after DOX. Thirty six pts had EPC/cardiac biomarkers and twenty nine pts had CMRs at all three time points. LVEF decreased 1.6% following completion of DOX (95% CI: −3.8 to 0.6, p = 0.16). There was a non-linear trend in EPCs over time (p = 0.05), with an initial increase followed by a decrease, with average values of 59 (95% CI: 50–70), 65 (95% CI: 55–75), and 50 (95% CI: 40–60), respectively, across the three time points. By the end of treatment, 54% (95% CI: 0.37–0.71) of women had abnormal troponins (median: 0.03, range: 0.02 to 0.17). Variables associated with abnormal troponins included lower baseline EPCs (p = 0.095), older age (p = 0.075) and initial increase in BNP post cycle 1 (p &lt; 0.03). In a multivariable model, age (p = 0.04) and BNP (p = 0.04) were independent prognostic factors for abnormal troponins, where the odds of abnormal troponins was 65% higher for every 5-year increase in age (OR = 1.65, 95% CI: 1.02–2.66) and 58% higher for every 1.5-fold increase in BNP (OR = 1.58, 95% CI: 1.01–2.46). Baseline EPC did not remain in the final model with p = 0.12.

Conclusions: DOX was well-tolerated with no significant changes in LVEF as measured by serials CMRs. Older age and increased BNP were independent prognostic factors for rise in Ti. We observed an initial increase of EPCs with DOX exposure followed by a decrease after the end of treatment. Although not statistically significant, lower EPCs at baseline, corresponding to lower cardiac reserve, were correlated with abnormal Ti. This is the first study reporting an intriguing association of EPCs with traditional cardiac biomarkers during DOX chemotherapy. Funded by R21 CA143787-02.

Citation Information: Cancer Res 2012;72(24 Suppl):Abstract nr P2-11-07.

Development and validation of sensitive liquid chromatography/tandem mass spectrometry method for quantification of bendamustine in mouse brain tissue

A liquid chromatography-tandem mass spectrometry method for quantification of bendamustine in mouse brain tissue was developed and fully validated. Methanol was used to precipitate proteins in brain tissue. Bendamustine and internal standard (chlorambucil) were separated with reverse-phase chromatography on a C-18 column with a gradient of water and 95% methanol in 0.1% formic acid. Positive mode electrospray ionization was applied with selected reaction monitoring to achieve 5 ng/ml lower limits of quantitation in mouse brain tissue. The calibration curve for bendamustine in mouse brain was linear between 5 and 2000 ng/ml. The within- and between-batch accuracy and precision of the assay were within 15% at 10, 100 and 1000 ng/ml. The recovery and matrix effect of bendamustine in mouse brain tissue ranged from 41.1% to 51.6% and 107.4% to 110.3%, respectively. The validated method was then applied to quantitate bendamustine in an animal study. Results indicate the assay can be applied to evaluate bendamustine disposition in mouse brain tissue. This assay will be applied in the future to detect and quantify bendamustine in human brain tissue samples.

Microcirculatory fraction (MCF(I)) as a potential imaging marker for tumor heterogeneity in breast cancer

Cancer is a heterogeneous disease by nature. Current imaging studies usually ignore intratumor variability in imaging biomarkers. We postulate that quantifying tumor heterogeneity with imaging techniques can provide useful information about cancer biology and potentially serve as novel imaging biomarkers. In this retrospective study, we identify a potential imaging marker, the microcirculatory fraction (MCF(I)), that quantifies tumor heterogeneity in normoxic/hypoxic cellular composition. We demonstrate its application on a test population of 22 women with stage II/III HER-2 negative breast cancer receiving antiangiogenic-cytotoxic combination neoadjuvant chemotherapy. Early change in MCF(I) (ΔMCF(I)) is assessed with dynamic contrast enhanced magnetic resonance imaging at the end of Cycle 2 and associated with pathologic response. Its performance is compared with other established volumetric imaging biomarkers (initial tumor volume and volume change) by statistical and graphic methods. We demonstrate that a significant (P<.01) difference in ΔMCF(I) can be detected between good (median ΔMCF(I) 0.27) and poor (median ΔMCF(I) -0.12) responders, despite the limited population size. Differences in the volumetric biomarkers are not statistically significant. Receiver operating characteristic analysis also shows that ΔMCF(I) is a good predictor for pathologic response (AUC=0.86, 95% CI 0.69-1.00, P<.01), while predictions made with the established volumetric biomarkers are not significantly better than random guesses. We conclude that ΔMCF(I) has the potential of being a better predictive biomarker for therapeutic response assessment. Our findings support our postulation that quantifying tumor heterogeneity with imaging techniques can provide additional information that can serve as novel biomarkers.

Phase I/II trial of non-cytotoxic suramin in combination with weekly paclitaxel in metastatic breast cancer treated with prior taxanes

PURPOSE

Suramin, a polysulfonated naphthylurea, inhibits the actions of polypeptide growth factors including acidic and basic fibroblast growth factors (aFGF and bFGF), which confer broad spectrum chemotherapy resistance. We hypothesized that suramin at non-cytotoxic doses in combination with weekly paclitaxel would be well tolerated and demonstrate anti-tumor activity.

METHODS

Women with metastatic breast cancer who had been previously treated with a taxane in the adjuvant or metastatic setting were eligible. The primary objective of the phase I was to determine the dose of intravenous (IV) weekly suramin that resulted in plasma concentrations between 10 and 50 umol/l over 8-48 h (or the target range) in combination with IV 80 mg/m(2) of weekly paclitaxel. The primary objective of the phase II trial was to determine the anti-tumor activity of the dosing regimen defined in phase I. Therapy was continued until disease progression or development of unacceptable toxicity.

RESULTS

Thirty-one patients were enrolled (9: phase I; 22: phase II). In phase I, no dose-limiting toxicities were observed. Pharmacokinetics during the first cycle showed suramin concentrations within the target range for 21 of 24 weekly treatments (88 %). In phase II, the objective response rate (ORR) was 23 % (95 % CI 8-45 %), the median progression-free survival was 3.4 months (95 % CI 2.1-4.9 months), and the median overall survival was 11.2 months (95 % CI 6.6-16.0 months).

CONCLUSIONS

Non-cytotoxic doses of suramin in combination with weekly paclitaxel were well tolerated. The efficacy was below the pre-specified criteria required to justify further investigation.

Abstract 5586: Phase I study of PARP inhibitor ABT-888 and carboplatin with novel imaging in metastatic breast cancer (MBC) (NCI-8609)

Purpose: ABT-888 is an oral inhibitor of PARP 1 and 2 and potentiates activity of platinums in preclinical models. We are conducting a phase I study of ABT-888 on 2 different schedules (7 and 14 day) plus q 3 week carboplatin (C) to identify the recommended phase II dose schedules (RPTD-7and 14 day) for this regimen in patients (pts) with MBC who are: (1) triple negative (TN); or (2) estrogen receptor positive (ER+) with defective Fanconi Anemia (FA) pathway (no FANCD2 foci in tumor). Study design: Eligible pts received C-AUC 5 Q 3weeks (except dose level 1-AUC 6) plus escalating doses of ABT-888 BID on a 7 or 14-day schedule using a 3+3 dose escalation design. Blood samples were collected during cycles 1 and 2 for PAR assay and CTCs isolated to measure gamma H2Ax. We performed 3′-[F-18] Fluoro-3′-deoxythymidine(FLT) PET scans to assess cellular tumor proliferation at baseline, cycle 1 day 7 and 14 and after cycle 3. FDG-PET-CT scans were used to assess response. Results: 22 pts (20-TN, 2-ER+ w/FA defect) with median age of 56.5 yrs (range 31-69) were enrolled on 5 dose levels. Dose level 1 with C at AUC 6 was too toxic with 3 DLTs (Table 1). Further dose escalations were performed with C at AUC-5. Dose reductions in C were made in subsequent cycles for thrombocytopenia, anemia and fatigue. Maximum reduction in thymidine uptake in tumors was seen on day 7 FLT scans. CTCs were isolated using an immunomagnetic negative depletion method on 8 pt samples to date (median-59, range 0-684 CTCs). Gamma H2Ax analysis on sequential samples is ongoing. Four pts have had an unconfirmed partial response (PR) with &gt; 50% tumor shrinkage; 2 of the 4 pts had a defective FA pathway. Conclusions: Thrombocytopenia is the major DLT when ABT-888 is given in combination with C, where lower AUC of C is better tolerated and shows promising activity of this combination. FA deficiency (5/14=27%) seen in this group is consistent with our previous reports. The study is supported U01 CA076576.

PD10-01: Prevalence of Dysfunctional Fanconi Anemia (FA) DNA Repair Pathway in Breast Cancer

Purpose: BRCA1/2 deficient breast tumors are highly sensitive to poly- ADP-ribose polymerase inhibitors (PARPi). The Fanconi Anemia (FA) associated gene products along with BRCA 1/2 function in a common pathway that regulates the cellular response to DNA damage, suggesting that tumors with dysfunction of any of the components of FA network would be susceptible to PARPi. Understanding the prevalence of such defects in breast tumors using reproducible methodology will help us target these tumors with novel agents and potentially improve outcomes. Hence we sought to assess the prevalence of FA pathway defect in breast tumors by the absence of nuclear FANCD2 (a pivotal protein in the FA/BRCA pathway which is monoubiquitylated in the nucleus in response to DNA damage) repair foci using a novel immunofluorescence method and correlate this with known molecular markers of breast cancer.

Methods: Using primary tumors obtained from the ongoing PARPi clinical trials (NCT01017640 and NCT01251874) and tumor bank, we evaluated 102 breast tumors for the somatic functionality of the FA pathway (FANCD2 foci formation) by the FA Triple Stain Immuno-Fluorescence (FATSI) test performed in a CLIA-certified laboratory using paraffin embedded tissues. The tissue sections are incubated with a primary antibody cocktail of rabbit polyclonal FANCD2 antibody and a monoclonal anti-Ki67 mouse antibody, followed by co-incubation with a secondary antibody (FITC conjugated to anti-rabbit IgG and Alexafluor 594 donkey anti-mouse), mounted on glass slides in a DAPI containing embedding medium and evaluated by a fluorescence microscope. Absence of nuclear FANCD2 formation in 100 proliferating tumor cells was considered positive for FA defect. Hormone receptor (HR) and Her2 status was compared between the groups using Fisher's exact test.

Results: A total of 102 primary breast tumors were analyzed for FANCD2 by FATSI test of which 62 were triple negative (TN), 37 were HR positive and 3 were Her2 positive. Of these, 29 tumors (28%) were positive for FA defect with no significant differences among the molecular subtypes (26% in TN vs 32% in HR + vs 33% in Her2+).

Phase II trial of neoadjuvant exemestane in combination with celecoxib in postmenopausal women who have breast cancer

PURPOSE

Within breast tissue, aromatase expression and activity is increased by prostaglandin E2, providing a rationale for combining the COX-2 inhibitor celecoxib with an aromatase inhibitor. To evaluate the effect of these drugs on aromatase and other biomarkers, a phase II trial of neoadjuvant exemestane followed sequentially by celecoxib plus exemestane was performed.

METHODS

Postmenopausal women with estrogen receptor (ER) and/or progesterone (PR) positive stages II-III breast cancers received 8 weeks of exemestane 25 mg daily, followed by 8 weeks of exemestane 25 mg daily and celecoxib 400 mg twice daily. Core biopsies were collected pretreatment, after 8 weeks of exemestane, and at definitive breast cancer surgery. A tissue microarray was constructed and immunohistochemistry (IHC) for aromatase, ER, PR, HER-2, Ki-67, and COX-2 was performed.

RESULTS

Twenty-two women were enrolled. Celecoxib was discontinued in 4 (18%) women for toxicity (all grade 1 and 2) and 2 (9%) developed serious cardiac events occurring at 1 and 4 months after completing treatment. By US, there were 8 (36%)-partial responses and 12 (55%)-stable disease. There were no pathological complete responses (pCR). There were statistically significant decreases in ER (P = .003), PR (P = .002), Ki-67 (P < .001), and COX-2 (P = .004) expression. No significant differences in aromatase or HER-2 expression were observed (P = .13 and P = .39, respectively).

CONCLUSION

The addition of celecoxib to exemestane was tolerated by the majority of women and anti-tumor response was observed. Additional studies, including gene expression, are required to more fully understand the basis for the decreased expression of ER, PR, Ki-67, and COX-2.

Abstract 3284: Isolation of circulating tumor cells (CTCs) with mesenchymal and stem cell markers in localized and metastatic breast cancer using a novel negative selection enrichment

Background: Breast circulating tumor cells (CTCs) are commonly isolated by positive selection enrichment technology, which targets the epithelial cell adhesion activating molecule, EpCAM. However, CTCs with low or no EpCAM expression, such as those from basal and normal-like subtypes, are more likely to be missed by this method. We developed a novel negative enrichment technology to detect CTCs with mesenchymal and stem cell markers in localized and metastatic breast cancer (BC).

Patients and Methods: Twenty nine patients with localized and metastatic BC initiating chemotherapy were enrolled. CTCs were isolated in 10 mL of peripheral blood using negative selection with immunomagnetic tagging and removal of CD45 positive cells at 3 time points: pretreatment, after one cycle of treatment (TP1) and at end of treatment or at disease progression in metastatic patients (TP2). Immunocytochemical staining for nucleus, cytokeratin (8,18,19), vimentin, and CD44 was completed on available samples. Double staining for nucleus and cytokeratin with high nucleus to cytoplasm ratio defined a CTC. Enrollment is ongoing.

Results: Median age was 57 yrs (range 28-78 yrs); stage distributions were I-2 (7%), II-10 (35%), III-3 (10%), and IV-14 (48%); 19 (66%) were estrogen receptor positive (ER+), 4 (14%) estrogen and progesterone receptor negative (ER-PR-HER2 non-overexpressing) and 6 (21%) HER2 overexpressing. Negative enrichment yielded an average log10 depletion of nucleated cells of 2.74 and an overall, average log10 depletion of 5.2 (&gt;100,000 enrichment). No CTCs were identified in 5 healthy volunteers or in buffy coats purchased from the Red Cross. CTCs were identified in all stages at pretreatment but decreased to 0 in three patients by TP1. Baseline median CTC level was 373/mL in localized BC (range 2.2-1975/mL) and 761/mL in metastatic BC (range 9.9-47513/mL). In localized BC, the median percent (%) change in CTCs was +2% at TP1 (n= 13; range −100% to +14945%) and −95% at TP2 (n=5; range −100% to −13%). In metastatic BC, median CTC numbers decreased by 41% at TP1 (n=11; range −100% to +4222%) and increased at TP2 in 2 patients by 231% and 730%. Baseline CTC levels and changes at TP1 were not significantly different between localized and metastatic groups by the Wilcoxen Rank Sum test. All tested CTCs expressed vimentin and CD44. In addition to CTCs, a population of cells without detectable cytokeratin expression but positive for the other markers was identified in some samples. Further characterization of these cells for epithelial mesenchymal transition markers is underway.

Conclusions: CTCs identified with this novel negative selection method have both mesenchymal and stem cell markers in localized and metastatic BC. Higher CTC numbers with epithelial characteristics are detected with this method relative to what is reported with positive selection.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 3284.

Phase II trial of pyrazoloacridine (NSC#366140) in patients with metastatic breast cancer

PURPOSE

Pyrazoloacridine (PZA) is an investigational nucleic acid binding agent that inhibits the activity of topoisomerases 1 and 2. We conducted a phase II clinical study to determine the efficacy and toxicities of PZA in patients with metastatic breast cancer (MBC).

EXPERIMENTAL DESIGN

In this phase II multicenter study, patients who were treated with no more than one prior chemotherapy for MBC were treated with 750 mg/m² of PZA given as a 3-hour intravenous infusion every 3 weeks. Treatment cycles were continued until disease progression or unacceptable toxicities. The study was designed to distinguish between a response rate of < 15% vs > 30% (alpha = 0.10, beta = 0.10) using Simons optimal 2-stage design. At least 2 responses were required in the first 12 patients in the 1st stage and 6 of 35 in the 2nd stage to recommend the agent for further study.

RESULTS

Two patients in the first stage had a response allowing accrual to second stage. A total of 15 patients (out of 35 planned) were treated on the study prior to premature closure. Three patients had a partial response (20%) lasting 4.5-6 months. Two patients had stable disease for 3 and 5 months. The dose limiting toxicity was granulocytopenia with ten patients requiring dose reduction or dose delay for grade 4 neutropenia. Other grade 3 and 4 toxicities include vomiting (n = 2), nausea (n = 2), neurotoxicity (n = 1), fatigue (n = 1), anemia (n = 1), dyspnea 9n = 1) and renal (n = 1).

CONCLUSIONS

Pyrazoloacridine demonstrated modest activity in patients with metastatic breast cancer.

Randomized phase II adjuvant trial of dose-dense docetaxel before or after doxorubicin plus cyclophosphamide in axillary node-positive breast cancer

PURPOSE

An anthracycline-based combination followed by, or combined with, a taxane is the sequence used in most adjuvant chemotherapy regimens. We hypothesized that administering the taxane before the anthracycline combination would be associated with fewer dose reductions and delays than the reverse sequence. To test this hypothesis, a randomized phase II multicenter adjuvant chemotherapy trial was performed.

PATIENTS AND METHODS

Fifty-six patients with axillary node-positive, nonmetastatic breast cancer were randomly assigned either to group A (docetaxel [DOC] 75 mg/m(2) intravenously [IV] every 14 days for four cycles followed by doxorubicin 60 mg/m(2) and cyclophosphamide 600 mg/m(2) [AC] IV every 14 days for four cycles); or to group B (AC followed by DOC) at the identical doses and schedule. Pegfilgrastim 6 mg subcutaneous injection was administered 1 day after the chemotherapy in all treatment cycles. The primary objective was to administer DOC without dose reductions or delays before or after AC and calculate the relative dose intensity (RDI) of DOC and AC.

RESULTS

The majority of toxicities were grade 0 to 2 irrespective of sequence. The RDI for DOC was 0.96 and 0.82, respectively, in groups A (DOC followed by AC) and B (AC followed by DOC), with more frequent dose reductions occurring in group B (46% v 18%). The RDI for AC was 0.95 and 0.98 in groups A and B, respectively.

CONCLUSION

The administration of DOC before AC results in fewer DOC dose reductions and a higher RDI than the reverse sequence. Larger trials evaluating the sequence of DOC before anthracyclines are justified.

Phase II study of weekly docetaxel and capecitabine in patients with metastatic breast cancer

PURPOSE

This phase II study evaluated the safety and efficacy of weekly docetaxel and capecitabine in patients with metastatic breast cancer.

PATIENTS AND METHODS

Thirty-nine patients with metastatic breast cancer received 30 mg/m2 of docetaxel on days 1, 8, and 15 in combination with capecitabine 800 mg/m2 twice daily on days 1-21, repeated every 28 days.

RESULTS

The median number of treatment cycles was 4 (range, 1-20 cycles). Grade 3 toxicities per patient were asthenia (n = 7; 18%), diarrhea (n = 7; 18%), nausea/vomiting (n = 5; 13%), stomatitis (n = 5; 13%), neutropenia (n = 5; 13%), and hand-foot syndrome (n = 4; 10%). There were only 2 grade 4 toxicities, febrile neutropenia and pulmonary embolism. The overall response rate was 44% (95% confidence interval (CI), 28%-60%), median duration of response was 9.1 months (95% CI, 6.2-12 months), and median time to progression was 5.5 months (95% CI, 3.7-7.3 months).

CONCLUSION

Weekly docetaxel with capecitabine was active with acceptable toxicities. Additional trials to define the optimal schedule of docetaxel and capecitabine are justified.

Phase II study of sequentially administered mitomycin (MMC) and irinotecan (CPT-11) in patients (pts) with metastatic breast cancer (MBC)

10542

Background: MMC and CPT-11 are synergistic in preclinical studies, as MMC increases expression of Topoisomerase I (Topo I), the target of CPT-11. Three out of 5 heavily pretreated MBC pts benefited from MMC and CPT-11 in a phase I trial. We designed a phase II trial of this combination in MBC pts and hypothesized that increased Topo I expression in peripheral blood mononuclear cells (PBMC) would correlate with longer time to progression (TTP). Methods: Pt eligibility: ECOG PS 2 or less; no more than 2 prior chemotherapy regimens for MBC; adequate organ function; measurable and non-measurable disease were permitted. Treatment: intravenous (IV) MMC-6 mg/m2 on day 1 and IV CPT-11–125 mg/m2 on days 2 and 8 every 28 days. Genotyping of NQ01 (enzyme that activates MMC) was evaluated by pyrosequencing; Topo I gene expression by reverse transcriptase-polymerase chain reaction (RT-PCR) was evaluated in PBMC pretreatment, 24 hrs, 48 hrs, and 8 days after MMC. Results: Thirty-two pts enrolled with the following characteristics: median age 50 years (range 29–73); median PS 0 (range 0–2); postmenopausal 29 (91%) pts; estrogen receptor (ER) negative 14 (44%) pts; HER-2/neu 3+ by IHC 7 (22%) pts, and 10 (31%) pts were ER(−), PR(−) and HER-2/neu (−). Six (19%) pts had no prior chemotherapy; 7 (22%)-1 prior regimen; and 19 (59%)-2 prior regimens. Pts received a median of 4 cycles (range 1–12). Four (12%) pts experienced grade 4 toxicity (1-neutropenia without fever, 1-abdominal pain, 1-pulmonary embolism, and 1-diarrhea). The most common grade 3 toxicities were neutropenia in 13(41%) pts, nausea in 7 (22%) pts, diarrhea in 6 (19%) pts, fatigue in 5 (16%) pts, and thrombocytopenia in 2 (6%) pts. Median TTP was 4.7 months (95% CI, 4.0 to 5.4 months). For 10 triple negative pts the median TTP of 5.4 months was not different. Baseline and induced Topo I gene expression was greatest in NQ01 wild-type genotype, however, increased Topo I expression in PBMC was associated with shorter TTP. Conclusions: Sequential administration of MMC and CPT-11 had acceptable toxicities and antitumor activity. Our hypothesis that increased Topo I expression in PBMC correlates with longer TTP was incorrect.

No significant financial relationships to disclose.

Phase II study of celecoxib in metastatic differentiated thyroid carcinoma

CONTEXT

There is increased cyclooxygenase-2 (COX-2) expression in malignant thyroid nodules compared with nonneoplastic and benign thyroid tissue.

OBJECTIVE

The objective of the study was to evaluate the efficacy of celecoxib, a selective COX-2 inhibitor, in treating patients with progressive metastatic differentiated thyroid cancer (DTC) and to explore the relationship of clinical response to tumor COX-2 expression with immunohistochemistry in a subset of patients.

DESIGN

The study was a prospective phase II trial with Fleming single-stage design powered at 80% with a 5% rejection error to detect more than 20% progression-free survival at 12 months.

SETTING

Ambulatory patients were from tertiary referral academic medical centers.

PATIENTS

Patients in the study had progressive metastatic DTC and had failed prior standard therapy.

INTERVENTION

Patients were treated with celecoxib 400 mg orally twice a day for 12 months.

MAIN OUTCOME MEASURE

The main outcome measure was progression-free survival at 12 months of treatment using Response Evaluation Criteria in Solid Tumors and/or serum thyroglobulin.

RESULTS

Twenty-three of 32 patients experienced progressive disease or stopped therapy due to toxicity, thus fulfilling the intent-to-treat study endpoint for celecoxib failure. One patient achieved partial response, and one patient completed 12 months of therapy progression-free. The patient with partial response was on therapy along with seven other patients when the study was terminated.

CONCLUSIONS

Celecoxib 400 mg orally twice per day fails to halt progressive metastatic DTC in most patients.

Determination of refractive index profiles of Ag+ -Na+ ion-exchange multimode strip waveguides by variable wavefront shear double-refracting interferometry microinterferometry

The results of experimental determination of multimode strip waveguide refractive index profiles and Ag concentration profiles obtained by using the variable wavefront shear double-refracting interferometry microinterferometer Biolar PI and an electron microprobe are presented. The strip waveguides under investigation are formed in soda lime glass in an external electric-field-assisted Ag+ -Na+ ion-exchange process from the molten AgNO3 salt by use of dielectric masks with channel apertures. A dry electrochemical technique of dielectric mask formation is applied. The influence of waveguide-forming parameters on the shape of Ag concentration profiles and the range of silver diffusion are shown. Changes in the usually assumed boundary conditions of electric-field calculations in ion-exchange numerical modeling are suggested.

Side diffusion modeling by the explicit consideration of a space-charge buildup under the mask during strip waveguide formation in the Ag+ -Na+ field-assisted ion-exchange process

A space-charge buildup under the blocking mask in a field-assisted Ag+ -Na+ ion-exchange modeling is assumed. It results in the distortion of electric field lines in the direction under the mask edges. As a result, side diffusion occurs and the numerical model shows the same range of side diffusion as the experimental data. Explicit consideration of the space-charge buildup under the mask and solving the Poisson equation for the electric field determination make it possible to use more realistic boundary conditions in the numerical model, compared to the boundary conditions generally used.