Treatment Efficacy Score-continuous residual cancer burden-based metric to compare neoadjuvant chemotherapy efficacy between randomized trial arms in breast cancer trials.

BACKGROUND: Difference in pathologic complete response (pCR) rate after neoadjuvant chemotherapy does not capture the impact of treatment on downstaging of residual cancer in the experimental arm. We developed a method to compare the entire distribution of residual cancer burden (RCB) values between clinical trial arms to better quantify the differences in cytotoxic efficacy of treatments. PATIENTS AND METHODS: The Treatment Efficacy Score (TES) reflects the area between the weighted cumulative distribution functions of RCB values from two trial arms. TES is based on a modified Kolmogorov-Smirnov test with added weight function to capture the importance of high RCB values and uses the area under the difference between two distribution functions as a statistical metric. The higher the TES the greater the shift to lower RCB values in the experimental arm. We developed TES from the durvalumab + olaparib arm (n = 72) and corresponding controls (n = 282) of the I-SPY2 trial. The 11 other experimental arms and control cohorts (n = 947) were used as validation sets to assess the performance of TES. We compared TES to Kolmogorov-Smirnov, Mann-Whitney, and Fisher's exact tests to identify trial arms with higher cytotoxic efficacy and assessed associations with trial arm level survival differences. Significance was assessed with a permutation test. RESULTS: In the validation set, TES identified arms with a higher pCR rate but was more accurate to identify regimens as less effective if treatment did not reduce the frequency of high RCB values, even if the pCR rate improved. The correlation between TES and survival was higher than the correlation between the pCR rate difference and survival. CONCLUSIONS: TES quantifies the difference between the entire distribution of pathologic responses observed in trial arms and could serve as a better early surrogate to predict trial arm level survival differences than pCR rate difference alone.

Risk of acute myeloid leukemia and myelodysplastic syndrome among older women receiving anthracycline-based adjuvant chemotherapy for breast cancer on Modern Cooperative Group Trials (Alliance A151511).

PURPOSE: We examined acute myeloid leukemia (AML) and myelodysplastic syndrome (MDS) events among 9679 women treated for breast cancer on four adjuvant Alliance for Clinical Trials in Oncology trials with >90 months of follow-up in order to better characterize the risk for AML/MDS in older patients receiving anthracyclines. METHODS: We used multivariable Cox regression to examine factors associated with AML/MDS, adjusting for age (≥65 vs. <65 years; separately for ≥70 vs. <70 years), race/ethnicity, insurance, performance status, and anthracycline receipt. We also examined the effect of cyclophosphamide, the interaction of anthracycline and age, and outcomes for those developing AML/MDS. RESULTS: On Cancer and Leukemia Group B (CALGB) 40101, 49907, 9344, and 9741, 7290 received anthracyclines; 15% were in the age ≥65 and 7% were ≥70. Overall, 47 patients developed AML/MDS (30 AML [0.3%], 17 MDS [0.2%]); 83% of events occurred within 5 years of study registration. Among those age ≥65 and ≥70, 0.8 and 1.0% developed AML/MDS (vs. 0.4% for age <65), respectively. In adjusted analyses, older age and anthracycline receipt were significantly associated with AML/MDS (adjusted hazard ratio [HR] for age ≥65 [vs. <65] = 3.13, 95% confidence interval [CI] 1.18-8.33; HR for anthracycline receipt [vs. no anthracycline] = 5.16, 95% CI 1.47-18.19). There was no interaction between age and anthracycline use. Deaths occurred in 70% of those developing AML/MDS. CONCLUSIONS: We observed an increased risk for AML/MDS for older patients and those receiving anthracyclines, though these events were rare. Our results help inform discussions surrounding anticipated toxicities of adjuvant chemotherapy in older patients.

Emerging innovations in clinical trial design.

Designs of clinical trials have changed little since the advent of randomization in the 1940s. Modern innovations in designs are being driven by the increasing recognition in clinical research that diseases are heterogeneous and patients who apparently have the same disease require different therapies. This article describes some innovations in clinical trial design across therapeutic areas but with a focus on oncology. No one knows what the future holds for clinical trial design but the status quo of large trials that pretend the patient population is homogeneous is not sustainable, either economically or scientifically/medically. No one knows what the eventual business model and regulatory model will be, but they will be very different from today's.

The Signature Program: Bringing the Protocol to the Patient.

Early-phase clinical development in oncology has evolved dramatically with the deciphering of the human genome in 2004. Genomic analysis and the tools identifying genetically disrupted pathways within a patient's tumor have been a driving force for personalized medicine and for the development of highly targeted novel therapies. Tumors are often genetically heterogeneous, with multiple concurrent genetic abnormalities. On the other hand, tumors arising from different tissues may share identical molecular drivers.

Assessment of local vocal fold deformation characteristics in an in vitro static tensile test.

Voice quality is strongly dependent on vocal fold dynamics, which in turn are dependent on lung pressure and vocal fold biomechanics. Numerical and physical models are often used to investigate the interactions of these different subsystems. However, the utility of numerical and physical models is limited unless appropriately validated with data from physiological models. Hence a method that enables analysis of local vocal fold deformations along the entire surface is presented. In static tensile tests, forces are applied to distinctive working points being located in cover and muscle, respectively, so that specific layer properties can be investigated. The forces are directed vertically upward and are applied along or above the vocal fold edge. The resulting deformations are analyzed using multiple perspectives and three-dimensional reconstruction. Deformation characteristics of four human vocal folds were investigated. Preliminary results showed two phases of deformation: a range with a small slope for small deformations fading into a significant nonlinear deformation trend with a high slope. An increase of tissue stiffness from posterior to anterior was detected. This trend is more significant for muscle and in the mid-anterior half of the vocal fold.

Tumour response interpretation with new tumour response criteria vs the World Health Organisation criteria in patients with bone-only metastatic breast cancer.

BACKGROUND: We compared the utility of a new response classification (MDA; based on computed tomography (CT), magnetic resonance imaging (MRI), plain radiography (XR), and skeletal scintigraphy (SS)) and the World Health Organisation response classification (WHO; based on XR and SS) in stratifying breast cancer patients with bone-only metastases with respect to progression-free survival (PFS), overall survival (OS), and clinical response. METHODS: We retrospectively reviewed 41 patients with bone-only metastatic breast cancer and assigned responses according to the MDA and WHO criteria. We analysed whether the MDA or WHO response classifications correlated with PFS and OS. RESULTS: With the MDA criteria, there were significant differences in PFS between patients classified as responders and those classified as nonresponders (P=0.025), but with the WHO criteria, there were not. Neither criteria distinguished responders from nonresponders in terms of OS. MDA response criteria correlated better than WHO response criteria with clinical response assessment. CONCLUSIONS: The MDA classification is superior to the WHO classification in differentiating between responders and nonresponders among breast cancer patients with bone-only metastases. Application of the MDA classification may allow bone lesions to be considered measurable disease. Prospective study is needed to test the MDA classification among patients with bone metastasis.

I-SPY 2: an adaptive breast cancer trial design in the setting of neoadjuvant chemotherapy.

I-SPY 2 (investigation of serial studies to predict your therapeutic response with imaging and molecular analysis 2) is a process targeting the rapid, focused clinical development of paired oncologic therapies and biomarkers. The framework is an adaptive phase II clinical trial design in the neoadjuvant setting for women with locally advanced breast cancer. I-SPY 2 is a collaborative effort among academic investigators, the National Cancer Institute, the US Food and Drug Administration, and the pharmaceutical and biotechnology industries under the auspices of the Foundation for the National Institutes of Health Biomarkers Consortium.

Empirical Eigenfunctions and medial surface dynamics of a human vocal fold.

OBJECTIVES: The purpose of this investigation was to use an excised human larynx to substantiate physical mechanisms of sustained vocal fold oscillation over a variety of phonatory conditions. During sustained, flow-induced oscillation, dynamical data was collected from the medial surface of the vocal fold. The method of Empirical Eigenfunctions was used to analyze the data and to probe physical mechanisms of sustained oscillation. METHODS: Thirty microsutures were mounted on the medial margin of a human vocal fold. Across five distinct phonatory conditions, the vocal fold was set into oscillation and imaged with a high-speed digital imaging system. The position coordinates of the sutures were extracted from the images and converted into physical coordinates. Empirical Eigenfunctions were computed from the time-varying physical coordinates, and mechanisms of sustained oscillation were explored. RESULTS: Using the method of Empirical Eigenfunctions, physical mechanisms of sustained vocal fold oscillation were substantiated. In particular, the essential dynamics of vocal fold vibration were captured by two dominant Empirical Eigenfunctions. The largest Eigenfunction primarily captured the alternating convergent/divergent shape of the medial surface of the vocal fold, while the second largest Eigenfunction primarily captured the lateral vibrations of the vocal fold. CONCLUSIONS: The hemi-larynx setup yielded a view of the medial surface of the vocal folds, revealing the tissue vibrations which produced sound. Through the use of Empirical Eigenfunctions, the underlying modes of vibration were computed, disclosing physical mechanisms of sustained vocal fold oscillation. The investigation substantiated previous theoretical analyses and yielded significant data to help evaluate and refine computational models of vocal fold vibration.

Phase III study of cyclophosphamide, doxorubicin, and fluorouracil (CAF) plus leucovorin versus CAF for metastatic breast cancer: Cancer and Leukemia Group B 9140.

PURPOSE: To determine whether biochemical modulation with LV (leucovorin) enhances the efficacy of CAF (cyclophosphamide, doxorubicin, and fluorouracil) against metastatic breast cancer. PATIENTS AND METHODS: Women with histologically confirmed stage IV breast cancer, Cancer and Leukemia Group B (CALGB) performance status 0 to 2, and no prior chemotherapy for metastatic disease were randomly assigned to receive CAF (cyclophosphamide 500 mg/m2 day 1, doxorubicin 40 mg/m2 day 1, and fluorouracil [FU] 200 mg/m2 intravenous bolus days 1 to 5) with or without LV (LV 200 mg/m2 over 30 minutes days 1 to 5 given 1 hour before FU). RESULTS: Two hundred forty-two patients were randomly assigned to treatment; 124 patients had visceral crisis and 40 patients had a CALGB performance status score of 2. The median follow-up was 6 years. The two study arms were similar with regard to serious adverse events; four patients died from treatment-related causes, two patients on each study arm. Predictive variables for time to treatment failure and survival were visceral disease and performance status. The overall response rate was 29% for CAF versus 28% for CAF plus LV. The median time to treatment failure (9 months) and median survival (1.7 years) did not differ by treatment arm. CONCLUSION: Modulation of CAF with LV improved neither response rates nor survival among women with metastatic breast cancer, compared with CAF alone. Multivariate analyses confirmed the prognostic importance of performance status and visceral crisis. However, the overall and complete response rates, response durations, time to treatment failure, and survival were the same in the two treatment arms.

Actin binding proteins: regulation of cytoskeletal microfilaments.

The actin cytoskeleton is a complex structure that performs a wide range of cellular functions. In 2001, significant advances were made to our understanding of the structure and function of actin monomers. Many of these are likely to help us understand and distinguish between the structural models of actin microfilaments. In particular, 1) the structure of actin was resolved from crystals in the absence of cocrystallized actin binding proteins (ABPs), 2) the prokaryotic ancestral gene of actin was crystallized and its function as a bacterial cytoskeleton was revealed, and 3) the structure of the Arp2/3 complex was described for the first time. In this review we selected several ABPs (ADF/cofilin, profilin, gelsolin, thymosin beta4, DNase I, CapZ, tropomodulin, and Arp2/3) that regulate actin-driven assembly, i.e., movement that is independent of motor proteins. They were chosen because 1) they represent a family of related proteins, 2) they are widely distributed in nature, 3) an atomic structure (or at least a plausible model) is available for each of them, and 4) each is expressed in significant quantities in cells. These ABPs perform the following cellular functions: 1) they maintain the population of unassembled but assembly-ready actin monomers (profilin), 2) they regulate the state of polymerization of filaments (ADF/cofilin, profilin), 3) they bind to and block the growing ends of actin filaments (gelsolin), 4) they nucleate actin assembly (gelsolin, Arp2/3, cofilin), 5) they sever actin filaments (gelsolin, ADF/cofilin), 6) they bind to the sides of actin filaments (gelsolin, Arp2/3), and 7) they cross-link actin filaments (Arp2/3). Some of these ABPs are essential, whereas others may form regulatory ternary complexes. Some play crucial roles in human disorders, and for all of them, there are good reasons why investigations into their structures and functions should continue.

Nuclear membrane proteins in failing human dilated cardiomyopathy.

Emerin (34 kDa) is a 254 amino acid protein located on the cytoplasmic surface of the inner nuclear membrane in cardiac muscle. It interacts with nuclear lamins and nuclear actin. Emerin is usually completely absent in Emery-Dreifuss muscular dystrophy, a condition that also manifests in the heart. Nuclear lamins are specialized nuclear proteins that line the inner nuclear membrane. Two isoforms, lamin A and C, differ in their C-terminal amino acids. Both are important in apoptosis and are degraded by caspase enzymes. Mutations in the rod domain of the lamin A/C gene are known to cause dilated cardiomyopathy (DCM) (Fatkin et al. New Engl. J. Med. 1999, 351, 1715-1724). We have used Western blots to detect emerin and lamin A/C in left ventricles from both nondiseased and failing DCM samples. The lamins form dimers, however it is not known if they are homodimers and / or heterodimers. In this report we compare and quantify expression levels of emerin from samples of left ventricles from ten failing DCM patients and five nondiseased (donor) hearts. We observed three lamin bands that suggest the expression of the three isoforms of the A-type lamin gene, lamin A, lamin C and lamin C2 (Ye et al. Subcellular Biochem. 1998, 31, 587-610). Preliminary data show that both lamin isoforms and emerin are present.

Monitoring a clinical trial conducted under the Food and Drug Administration regulations allowing a waiver of prospective informed consent: the diaspirin cross-linked hemoglobin traumatic hemorrhagic shock efficacy trial.

In 1996, the US Food and Drug Administration (FDA) enacted Rule 21 CFR section 50.24, which allows a narrow exception to the requirement for prospective informed consent from human research subjects in clinical trials investigating potentially beneficial therapies for acute, life-threatening conditions. The first clinical trial to be conducted under this rule was sponsored by Baxter Healthcare Corporation and approved by the FDA on November 21, 1996. This large, multicenter, randomized clinical trial was designed to compare the addition of diaspirin cross-linked hemoglobin (DCLHb) with standard care in the initial resuscitation of adults experiencing severe, uncompensated, traumatic hemorrhagic shock. Before the first planned interim analysis of the data, review of fatal adverse events revealed an imbalance in mortality between the 2 treatment groups. The Data Monitoring Committee (DMC) recommended suspension of patient enrollment 24 days later. Additional data collection and analyses confirmed the excess number of deaths in patients treated with DCLHb but failed to reveal the cause of these deaths. The trial was formally terminated after only 112 of the planned 850 patients had been enrolled. We review the events leading up to and the rationale behind the DMC recommendations for suspension of patient enrollment and trial termination. Although the DCLHb trial was unsuccessful in achieving its goals, the monitoring process worked well. Emergency research was facilitated by DMC oversight, and the interests of research subjects were protected by the actions of the DMC.

Circulating HER-2/erbB-2/c-neu (HER-2) extracellular domain as a prognostic factor in patients with metastatic breast cancer: Cancer and Leukemia Group B Study 8662.

PURPOSE: The HER-2/erbB-2/c-neu (HER-2) proto-oncogene is a M(r) 185,000 transmembrane tyrosine kinase that is amplified and/or overexpressed by 20-40% of breast cancers. HER-2 has been associated with worse prognosis and resistance or sensitivity to specific treatment. We evaluated circulating levels of extracellular domain of HER-2 (ECD/HER-2) in metastatic breast cancer patients and investigated the prognostic and predictive significance of circulating HER-2 levels regarding endocrine therapy or chemotherapy. EXPERIMENTAL DESIGN: Plasma samples from 242 patients were assayed for circulating ECD/HER-2 levels, using a sandwich enzyme immunoassay. ECD/HER-2 was correlated with clinical data gathered from these patients while they were participating in prospective Cancer and Leukemia Group B (CALGB) therapeutic protocols for metastatic breast cancer. RESULTS: Eighty-nine (37%) of 242 patients had elevated ECD/HER-2 levels (> or =10.5 ng/ml). ECD/HER-2 was significantly associated with tumor burden, progesterone receptor levels, and presence of visceral metastases. Patients with elevated pretreatment levels had a significantly shorter OS but not time-to-progression than did those with ECD/HER-2 levels <10.5 ng/ml in univariate analysis. In univariate but not multivariate subset analyses, among patients treated with endocrine therapy (megestrol acetate), elevated initial ECD/HER-2 was associated with worse OS compared with nonelevated patients. However, among patients treated with chemotherapy (mainly anthracycline-containing regimens), OS did not differ significantly. Rates of response to either endocrine therapy or chemotherapy were similar for patients with elevated and nonelevated ECD/HER-2 levels. CONCLUSIONS: ECD/HER-2 levels are elevated in 35-40% of patients with metastatic breast cancer. Elevated ECD/HER-2 levels are associated with a poorer prognosis in these patients. However, no predictive role for ECD/HER-2 was identified, either for endocrine therapy or for anthracycline-based chemotherapy in the metastatic setting.

Cancer genomics: promises and complexities.

The impending final deciphering of the complete human genome, coupled with the advancement of high-throughput technologies, is positioned to bring about a fundamental transformation in cancer research. The era of molecular biology is transforming into the era of genomic biology, with an unprecedented promise of understanding multifactorial diseases and of identifying specific targets that can be used to develop patient-tailored therapies. Although the genomic approach is in an early phase of its development and its tools need to be honed, the application of genomic technologies to cancer research has already generated exciting results both in target identification and in disease classification. In this article, we review some of the developments pertinent to cancer research, discuss potentially problematic areas associated with them, and comment on future trends and issues.

Characterization of the medial surface of the vocal folds.

A method is developed for the quantification of the medial surface of the vocal folds in excised larynges. Lead molds were constructed from the glottal airway of a canine larynx for 3 distinct glottal configurations corresponding to "pressed" folds, just barely adducted folds, and 1-mm-abducted folds as measured between the vocal processes. With a high-resolution laser striping system, the 3-dimensional molds were digitally scanned. Low-order polynomials were fitted to the data, and goodness-of-fit statistics were reported. For all glottal configurations, a linear variation (flat surface) approximated the data with a coefficient of determination of 90%. This coefficient increased to roughly 95% when a quadratic variation (curvature) was included along the vertical dimension. If more than the top 5 mm or so of the folds was included (the portion usually corresponding to vibration), a cubic variation along the vertical dimension was necessary to explain a change in concavity at the conus elasticus. These findings suggest the utility of a model based on a convergence coefficient and a bulging coefficient. For all glottal configurations, the convergence coefficients and bulging coefficients can be computed. Because pre-phonatory conditions have a profound influence on vocal fold vibration and on the quality of phonation, such shaping parameters are highly significant. With the viability of this method substantiated, it is envisioned that future studies will characterize greater quantities of glottal shapes, including those of human vocal folds.

Comparison of methods of measuring HER-2 in metastatic breast cancer patients treated with high-dose chemotherapy.

PURPOSE: HER-2 is overexpressed in 20% to 30% of human breast cancer and is associated with poor outcome. Studies suggest an association between HER-2 overexpression and resistance to alkylating agents. To further evaluate this relationship, we assessed the interaction of HER-2, measured by different methods, and outcome after dose intensification with alkylating agents in metastatic breast cancer. PATIENTS AND METHODS: From 1988 to 1995 at Duke University, 425 patients with metastatic breast cancer were enrolled in a study of high-dose alkylating agents (HDC) with autologous cellular support after doxorubicin-based therapy (AFM). HER-2 was measured in serum for shed extracellular domain (ECD) and in tissue by immunohistochemistry (IHC) and fluorescent in situ hybridization (FISH). RESULTS: HER-2 ECD was positive in 29% (19 of 65) of patients pre-AFM and in 11.7% (34 of 290) pre-HDC. Higher pre-AFM and higher pre-HDC HER-2 ECD predicted worse overall survival (P =.045 and P =.0096, respectively). HER-2 overexpression by IHC and FISH showed no correlation with worse disease-free survival or overall survival. FISH and ECD were highly specific for IHC (97.3% and 97.7% respectively). However, ECD had a low sensitivity for IHC-only 22% of patients with HER-2 in the primary tumor shed ECD into the serum. CONCLUSION: These data suggest that the method of measuring HER-2 is important in predicting clinical outcome. HER2 ECD may identify a poor prognosis subgroup of HER-2-positive tumors. Lack of association of HER2 by IHC/FISH with worse outcome suggests that therapy with AFM and/or HDC therapy may be able to overcome the effect of this prognostic factor or it may not be a prognostic factor in this setting.

A quantitative output-cost ratio in voice production.

A quantitative output-cost ratio (OCR) is proposed for objective use in voice production and is defined as the ratio of the acoustic output intensity to the collision intensity of the vocal folds. Measurement of the OCR is demonstrated in a laboratory experiment using 5 excised larynges and a transducer designed for use on human subjects. Data were gathered at constant fundamental frequency (150 Hz). Subglottal pressure was varied from 1.0 to 1.6 kPa, and glottal width at the vocal processes was varied from a pressed condition to a 2-mm gap. The OCR was plotted as a function of glottal width. With no vocal tract, the excised larynx experiments yielded a broad maxima in the OCR curves, across all subglottal pressure conditions, at about 0.6 mm. Computer simulations indicate that sharper maxima may occur when the influence of the vocal tract is taken into account. The potential clinical utility of the OCR is discussed for treatment of a wide range of voice disorders, including those involving both hyper- and hypoadduction.