First application of the Automated QUantitative Analysis (AQUA) technique to quantify PTEN protein expression in ovarian cancer: A correlative study of NCIC CTG OV.16.

BACKGROUND: Platinum resistance is a dominant cause of poor outcomes in advanced ovarian cancer (OC). A mechanism of platinum resistance is the inhibition of apoptosis through phosphatidylinositol 3 kinase (PI3K) pathway activation. The role of phosphatase and tensin homolog (PTEN), a negative regulator of this pathway, as a tumor biomarker is unclear. Quantitative analysis of PTEN expression as an alternative to immunohistochemistry has not been considered. PATIENTS AND METHODS: In 238 patient tumors from the NCIC-CTG trial OV.16, PTEN protein expression was quantified by Automated QUantitative Analysis (AQUA). Cox model was used to study the association between PTEN expression and clinical outcomes using a minimum p-value approach in univariate analysis. Multivariate analysis was used to adjust for clinical and pathological parameters. RESULTS: PTEN scores (range 13.9-192.3) of the 202 samples that passed quality control were analyzed. In univariate analysis, there was a trend suggesting an association between PTEN expression by AQUA as a binary variable (low ≤61 vs high >61) and progression free survival (HR=0.77, p=0.083), and in multivariate analysis, this association approached significance (HR=0.74, p=0.059). The relationship between quantitative PTEN expression and PFS differed (p=0.01 for interaction) by the extent of surgical debulking (residual disease (RD) <1cm or ≥1cm), with a numerically superior PFS in patients with high PTEN (23.5 vs 14.9m) only when RD<1cm (p=0.19). There was no association between PTEN levels and overall survival. CONCLUSIONS: AQUA is a novel method to measure PTEN expression. Further study of PTEN as a biomarker in OC is warranted.

Outcome of patients with primary refractory diffuse large B cell lymphoma after R-CHOP treatment.

Primary refractory diffuse large B cell lymphoma (DLBCL) following R-CHOP chemotherapy is a major concern. We identified 1126 patients with DLBCL treated with R-CHOP from 2000 to 2009, of whom 166 (15 %) had primary refractory disease. Of the 75/166 (45 %) who were age <70 years and had been planned for stage-directed curative therapy, 43 (57 %) were primary nonresponders and 32 (43 %) relapsed within 3 months of completing R-CHOP. Thirty of 75 (40 %) patients had serious comorbidity and organ dysfunction precluding intensive treatment and had palliative treatment only. Twelve of 45 (27 %) patients responded to second-line treatment and underwent ASCT. The median overall survival for the 75 patients was 10 months with only seven patients alive without evidence of disease at follow-up ranging from 14 to 106 months. Primary refractory DLBCL after R-CHOP has a very poor outcome with only anecdotal survivors independent of the intended treatment approach.

A phase II study single agent of aflibercept (VEGF Trap) in patients with recurrent or metastatic gynecologic carcinosarcomas and uterine leiomyosarcoma. A trial of the Princess Margaret Hospital, Chicago and California Cancer Phase II Consortia.

OBJECTIVE: The aim of this multi-institutional non randomized phase II trial was to determine the efficacy and safety of single agent aflibercept (VEGF Trap), a recombinant fusion protein that blocks multiple vascular endothelial growth factor isoforms, in women with gynecologic soft tissue sarcoma. METHODS: Patients were enrolled in two cohorts each with Simon two stage designs: uterine leiomyosarcoma and carcinosarcoma of endometrial, ovarian or fallopian tube origin. Eligibility criteria included ≤2 prior lines of chemotherapy for metastatic disease and ECOG performance status of ≤2. Aflibercept 4mg/kg was administered intravenously on day 1 of a 14 day cycle. Primary endpoints were objective response and disease stabilization (Progression Free Survival (PFS) at 6 months). RESULTS: 41 patients with uterine leiomyosarcoma and 22 patients with carcinosarcoma (19 uterine, 3 ovarian) were enrolled on study. In the leiomyosarcoma cohort, eleven (27%) patients had stable disease (SD), 4 with SD lasting at least 24 weeks. The 6 month PFS was 17%, with median time to progression (TTP) of 1.8 (95% CI:1.6-2.1) months. In the carcinosarcoma cohort, two (9%) patients had SD, one lasting >24 weeks, median TTP was 1.6 months (95%CI: 1.1-1.7) No partial responses were observed in patients from either cohort. Grade 3 or more aflibercept related toxicity was uncommon and included hypertension, fatigue, headache and abdominal pain. CONCLUSIONS: Single agent aflibercept has modest activity in patients with uterine leiomyosarcoma and minimal activity in women with carcinosarcoma.

Histotype predicts the curative potential of radiotherapy: the example of ovarian cancers.

BACKGROUND: To explore the influence of ovarian cancer histotype on the effectiveness of adjuvant radiotherapy (RT). METHODS: A review of a population-based experience included all referred women with no reported macroscopic residuum following primary surgery who underwent adjuvant platin-based chemotherapy (CT), with or without sequential RT, and for whom it was possible to assign histotype according to the contemporary criteria. RESULTS: Seven hundred and three subjects were eligible, of these 351 received RT. For those with apparent stage I and II tumors, the cohort with clear cell (C), endometrioid (E), and mucinous (M) disease who additionally received RT exhibited a 40% reduction in disease-specific mortality and a 43% reduction in overall mortality. CONCLUSIONS: The curability of those with stage I and II C-, E-, and M-type ovarian carcinomas was enhanced by RT-containing adjuvant therapy. This benefit did not extend to those with stage III or serous tumors. These findings necessitate reassessments of the role of RT and of the nonselective surgical and CT approaches that have characterized ovarian cancer care.

Breast cancer 1 (BRCA1) protein expression as a prognostic marker in sporadic epithelial ovarian carcinoma: an NCIC CTG OV.16 correlative study.

BACKGROUND: Breast cancer 1 (BRCA1) protein inactivation in sporadic ovarian carcinoma (OC) is common and low BRCA1 expression is linked with platinum sensitivity. The clinical validation of BRCA1 as a prognostic marker in OC remains unresolved. PATIENTS AND METHODS: In 251 patient samples from the NCIC CTG clinical trial, OV.16, BRCA1 protein expression was determined by immunohistochemistry. RESULTS: For all patients, when BRCA1 score was analyzed as a continuous variable, there was no significant correlation between BRCA1 protein expression and progression-free survival (PFS) [adjusted hazard ratio (HR) = 1.15 (0.96-1.37), P = 0.12] or response rate [HR = 0.89 (0.70-1.12), P = 0.32]. In the 116 patients with minimal residual disease (RD), higher BRCA1 expression correlated significantly with worse PFS [HR = 1.40 (1.04-1.89), P = 0.03]. Subgroup analysis divided patients with minimal RD into low (BRCA1 ≤2.5) and high (BRCA1 >2.5) expression groups. Patients with low BRCA1 expression had a more favorable outcome [median PFS was 24.7 and 16.6 months in patients with low and high BRCA1, respectively; HR = 0.56 (0.35-0.89), P = 0.01]. CONCLUSIONS: This study suggests that BRCA1 protein is a prognostic marker in sporadic OC patients with minimal RD. Further research is needed to evaluate BRCA1 as a predictive biomarker and to target BRCA1 expression to enhance chemotherapeutic sensitivity.

CA 125 normalization with chemotherapy is independently predictive of survival in advanced endometrial cancer.

OBJECTIVE: Changes in CA 125 with chemotherapy predict outcome for epithelial ovarian cancer. There is no such data for advanced endometrial cancer. METHOD: Retrospective review of all women receiving carboplatin and paclitaxel for advanced endometrial cancer at any of the institutions of the British Columbia Cancer Agency between September 1995 and September 2006. RESULTS: 185 newly diagnosed women were treated. Univariable analysis for progression-free survival identified as adverse predictors: grade 3, positive residual, age > 60, deep myometrial invasion, increasing stage/substage, papillary serous subtype, presence of cervical involvement, ECOG 1 or greater, CA 125 above 35 either preoperatively or at start of cycle 1 and CA 125 greater than 24 at the start of cycle 3. Upon multivariate analysis, CA 125 above 24 at cycle 3, grade 3 and positive residual remained as independent predictors. The single most important factor identified by decision tree analysis was CA 125 level at cycle 3. CONCLUSION: As with epithelial ovarian cancer, changes in CA 125 are highly predictive of outcome for advanced, chemotherapy treated endometrial cancer.

Exploring palliative treatment outcomes in women with advanced or recurrent ovarian clear cell carcinoma.

OBJECTIVE: Clear cell carcinoma (CCC) of the ovary is increasingly recognized as responding poorly to chemotherapy (CT). This review examines the outcomes achieved with a variety of CT regimens, looking for evidence of activity that might guide the development of more effective treatments. METHODS: A retrospective chart review of all cases of CCC referred to the BC Cancer Agency (BCCA) between 2000 and 2008 was conducted. Data were collected from those with primarily advanced disease and from those who recurred after adjuvant treatment. Outcomes were measured using broad definitions of treatment benefit (any objective or subjective evidence of disease control) in order to reflect the real-life use of palliative therapy. RESULTS: There were 158 women with pure CCC. First-line therapy for advanced disease was delivered to 33 patients. Second- and third-line treatment was delivered to 47 and 25 patients, respectively. The total number of treatment courses was 105: 88 CT-alone courses, 14 radiation therapy (RT)-alone and 3 combined modality. Treatment benefit was recorded in 24% of patients receiving CT, 64% of patients receiving RT, and each who received combined modality treatment. There was no CT drug class identified as obviously efficacious. CONCLUSION: Most patients with advanced or recurrent CCC have a low benefit-to-failure ratio from palliative CT. The role of RT and targeted agents must be explored to improve clinical outcomes for such patients.

Haemodynamics and blood flow measured using ultrasound imaging.

Visualization of, and measurements related to, haemodynamic phenomena in arteries may be made using ultrasound systems. Most ultrasound technology relies on simple measurements of blood velocity taken from a single site, such as the peak systolic velocity for assessment of the degree of lumen reduction caused by an arterial stenosis. Real-time two-dimensional (2D) flow field visualization is possible using several methods, such as colour flow, blood flow imaging, and echo particle image velocimetry; these have applications in the examination of the flow field in diseased arteries and in heart chambers. Three-dimensional (3D) and four-dimensional ultrasound systems have been described. These have been used to provide 2D velocity profile data for the estimation of volumetric flow. However, they are limited for haemodynamic evaluation in that they provide only one component of the velocity. The provision of all seven components (three space, three velocity, and one time) is possible using image-guided modelling, in which 3D ultrasound is combined with computational fluid dynamics. This method also allows estimation of turbulence data and of relevant quantities such as the wall shear stress.

Fluid-structure interaction in axially symmetric models of abdominal aortic aneurysms.

Abdominal aortic aneurysm disease progression is probably influenced by tissue stresses and blood flow conditions and so accurate estimation of these will increase understanding of the disease and may lead to improved clinical practice. In this work the blood flow and tissue stresses in axially symmetric aneurysms are calculated using a complete fluid-structure interaction as a benchmark for calculating the error introduced by simpler calculations: rigid walled for the blood flow, homogeneous pressure for the tissue stress, as well as one-way-coupled interactions. The error in the peak von Mises stress in a homogeneous pressure calculation compared with a fluid-structure interaction calculation was less than 3.5 per cent for aneurysm diameters up to 7 cm. The error in the mean wall shear stress, in a rigid-walled calculation compared with a fluid-structure interaction calculation, varied from 30 per cent to 60 per cent with increasing aneurysm diameter. These results suggest that incorporation of the fluid-structure interaction is unnecessary for purely mechanical modelling, with the aim of evaluating the current rupture probability. However, for more complex biological modelling, perhaps with the aim of predicting the progress of the disease, where accurate estimation of the wall shear stress is essential, some form of fluid-structure interaction is necessary.

Preoperative tumor markers at diagnosis in women with malignant mixed müllerian tumors/carcinosarcoma of the uterus.

CA125 is a well-recognized marker for endometrial cancer. Uterine malignant mixed müllerian tumors (MMMTs) are increasingly being recognized as an aggressive adenocarcinoma, not a sarcoma. There are no data in the literature regarding CA125 in this malignancy. One hundred twelve women with surgically staged MMMT, diagnosed between July 1990 and September 2005, had a retrospective chart review performed. Preoperative CA125 levels were available in 29 (26%) women. Seventeen (49%) women had levels above the upper limit of normal of 35 kmicro/L. Mean levels increased with increasing surgical stage: stage I 53.4 kmicro/L; stage II 122.5 kmicro/L; stage III 147.1 kmicro/L; and stage IV 428.4 kmicro/L. Elevated levels of CA19-9, CEA, and CA15-3 were found in 8%, 12%, and 25%, respectively.

Inadequate Rates of BRCA Testing with its Negative Consequences for Women with Epithelial Ovarian Cancer and their Families: an Overview of the Literature.

Fifteen per cent of women with epithelial ovarian cancer possess inherited mutations in the BRCA genes. Knowledge of her BRCA status is important to her and her family. Poly(ADP-ribose) polymerase (PARP) inhibitors provide a new therapeutic option for her. For her family it provides the opportunity for the prevention of what otherwise is often a lethal disease. To access these opportunities, the mandatory first step is testing the woman with the cancer. However, referral rates for genetic counselling and subsequent BRCA testing are low, in the of 10-30% range. The current paradigm needs the patient to be referred to genetics, be counselled and then undergo testing. Such an ad hoc process will never be 100% successful. Removing the human element by using reflex tumour testing as part of the routine pathological analysis is an obvious solution. Now 100% of women carrying mutations will be identified. Subsequent testing within the family would identify all the carriers, who would then be eligible for risk-reducing surgery. The current process for this is also flawed, with significant drop off at each stage, as it involves the woman with epithelial ovarian carcinoma and a mutation providing the information to her family who then in turn need to be referred or make an appointment for genetic counselling/testing and then, finally, if carrying the mutation, make a decision about risk-reducing surgery. Process improvements and education can help to diminish these roadblocks. The relevant available literature has been reviewed in order to provide an extensive overview of this broad topic with actual rates of counselling/testing at each step, the uptake of risk-reducing surgery and some solutions to make the process more effective. The value of PARP inhibitors and surgical prevention are also discussed, but in a more condensed format.

Numerical analysis of pulsatile blood flow and vessel wall mechanics in different degrees of stenoses.

Hemodynamics factors and biomechanical forces play key roles in atherogenesis, plaque development and final rupture. In this paper, we investigated the flow field and stress field for different degrees of stenoses under physiological conditions. Disease is modelled as axisymmetric cosine shape stenoses with varying diameter reductions of 30%, 50% and 70%, respectively. A simulation model which incorporates fluid-structure interaction, a turbulence model and realistic boundary conditions has been developed. The results show that wall motion is constrained at the throat by 60% for the 30% stenosis and 85% for the 50% stenosis; while for the 70% stenosis, wall motion at the throat is negligible through the whole cycle. Peak velocity at the throat varies from 1.47 m/s in the 30% stenosis to 3.2m/s in the 70% stenosis against a value of 0.78 m/s in healthy arteries. Peak wall shear stress values greater than 100 Pa were found for > or =50% stenoses, which in vivo could lead to endothelial stripping. Maximum circumferential stress was found at the shoulders of plaques. The results from this investigation suggest that severe stenoses inhibit wall motion, resulting in higher blood velocities and higher peak wall shear stress, and localization of hoop stress. These factors may contribute to further development and rupture of plaques.

Anatomical flow phantoms of the nonplanar carotid bifurcation, part II: experimental validation with Doppler ultrasound.

A nonplanar wall-less anatomical flow phantom of a healthy human carotid artery is described, the construction of which is based on a lost-core technique described in the companion paper (Part I) by . The core was made by rapid prototyping of an idealized three-dimensional computer model of the carotid artery. Flow phantoms were built using these idealized non planar carotid artery bifurcations. Physiologically realistic flow waveforms were produced with resistance index values of 0.75, 0.72 and 0.63 in the common, external and internal carotid artery branches, respectively. Distension of the common carotid using M-mode imaging was found to be at 10% of diameter. Although differences in vessel diameter between the phantom and that of the original computer model were statistically significant (p < 0.05), there was no difference (p > 0.05) in measurements made on the lost-cores and those obtained by B-mode ultrasound on the resulting flow phantoms. In conclusion, it was possible to reliably reproduce geometrically similar anatomical flow phantoms that are capable of producing realistic physiological flow patterns and distensions.

Anatomical flow phantoms of the nonplanar carotid bifurcation, part I: computer-aided design and fabrication.

Doppler ultrasound is widely used in the diagnosis and monitoring of arterial disease. Current clinical measurement systems make use of continuous and pulsed ultrasound to measure blood flow velocity; however, the uncertainty associated with these measurements is great, which has serious implications for the screening of patients for treatment. Because local blood flow dynamics depend to a great extent on the geometry of the affected vessels, there is a need to develop anatomically accurate arterial flow phantoms with which to assess the accuracy of Doppler blood flow measurements made in diseased vessels. In this paper, we describe the computer-aided design and manufacturing (CAD-CAM) techniques that we used to fabricate anatomical flow phantoms based on images acquired by time-of-flight magnetic resonance imaging (TOF-MRI). Three-dimensional CAD models of the carotid bifurcation were generated from data acquired from sequential MRI slice scans, from which solid master patterns were made by means of stereolithography. Thereafter, an investment casting procedure was used to fabricate identical flow phantoms for use in parallel experiments involving both laser and Doppler ultrasound measurement techniques.

Finite element analysis to investigate variability of MR elastography in the human thigh.

PURPOSE: To develop finite element analysis (FEA) of magnetic resonance elastography (MRE) in the human thigh and investigate inter-individual variability of measurement of muscle mechanical properties. METHODS: Segmentation was performed on MRI datasets of the human thigh from 5 individuals and FEA models consisting of 12 muscles and surrounding tissue created. The same material properties were applied to each tissue type and a previously developed transient FEA method of simulating MRE using Abaqus was performed at 4 frequencies. Synthetic noise was applied to the simulated data at various levels before inversion was performed using the Elastography Software Pipeline. Maps of material properties were created and visually assessed to determine key features. The coefficient of variation (CoV) was used to assess the variability of measurements in each individual muscle and in the groups of muscles across the subjects. Mean measurements for the set of muscles were ranked in size order and compared with the expected ranking. RESULTS: At noise levels of 2% the CoV in measurements of |G*| ranged from 5.3 to 21.9% and from 7.1 to 36.1% for measurements of ϕ in the individual muscles. A positive correlation (R2 value 0.80) was attained when the expected and measured |G*| ranking were compared, whilst a negative correlation (R2 value 0.43) was found for ϕ. CONCLUSIONS: Created elastograms demonstrated good definition of muscle structure and were robust to noise. Variability of measurements across the 5 subjects was dramatically lower for |G*| than it was for ϕ. This large variability in ϕ measurements was attributed to artefacts.

Design and characterisation of a wall motion phantom.

Arterial wall motion is an essential feature of a healthy cardiovascular system and it is known that wall motion is affected by age and disease. In recent years, methods have been developed for measurement of wall motion with the intention of providing diagnostically useful information. An issue with all of these techniques is the accuracy and variability of both wall motion and derived quantities such as elasticity, which requires the development of suitable test tools. In this paper, a vessel wall phantom is described for use in ultrasound studies of wall motion. The vessel was made from polyvinyl alcohol (PVA) subjected to a freeze-thaw process to form a cryogel (PVA-C). The elastic modulus, acoustic velocity and attenuation coefficient varied from 57 kPa, 1543 m s(-1) and 0.18 dB cm(-1) MHz(-1) for one freeze-thaw cycle to 330 kPa, 1583 m s(-1) and 0.42 dB cm(-1) MHz(-1) for 10 freeze-thaw cycles. Wall motion was effected by the use of pulsatile flow produced from a gear pump. The use of a downstream flow resistor removed gross distortions in the wall motion waveform, possibly by removal of reflected pressure waves. However, a low amplitude 20 Hz oscillation remained, which is unphysiologic and thought to be caused by the vibration of the distended PVA-C vessel.

The simulation of magnetic resonance elastography through atherosclerosis.

The clinical diagnosis of atherosclerosis via the measurement of stenosis size is widely acknowledged as an imperfect criterion. The vulnerability of an atherosclerotic plaque to rupture is associated with its mechanical properties. The potential to image these mechanical properties using magnetic resonance elastography (MRE) was investigated through synthetic datasets. An image of the steady state wave propagation, equivalent to the first harmonic, can be extracted directly from finite element analysis. Inversion of this displacement data yields a map of the shear modulus, known as an elastogram. The variation of plaque composition, stenosis size, Gaussian noise, filter thresholds and excitation frequency were explored. A decreasing mean shear modulus with an increasing lipid composition was identified through all stenosis sizes. However the inversion algorithm showed sensitivity to parameter variation leading to artefacts which disrupted both the elastograms and quantitative trends. As noise was increased up to a realistic level, the contrast was maintained between the fully fibrous and lipid plaques but lost between the interim compositions. Although incorporating a Butterworth filter improved the performance of the algorithm, restrictive filter thresholds resulted in a reduction of the sensitivity of the algorithm to composition and noise variation. Increasing the excitation frequency improved the techniques ability to image the magnitude of the shear modulus and identify a contrast between compositions. In conclusion, whilst the technique has the potential to image the shear modulus of atherosclerotic plaques, future research will require the integration of a heterogeneous inversion algorithm.

Oral etoposide is active against platinum-resistant epithelial ovarian cancer.

PURPOSE: To determine whether etoposide (VP16) is more effective when administered on a chronic schedule, women with clinically defined platinum-resistant epithelial ovarian cancer (EOC) were studied. PATIENTS AND METHODS: Thirty-one eligible women were treated with oral VP16. The first seven received a dose that varied depending on their body-surface area, but this proved too toxic, and so a fixed dose of 100 mg orally per day for 14 days every 3 weeks was used for the other subjects. RESULTS: The response rate was 26% (95% confidence interval [CI], 11% to 41%). The 28 women with cancer that had progressed while they were receiving a platinum analog had a response rate of 21% (95% CI, 6% to 36%). Response durations were short. CONCLUSION: When administered on this chronic schedule, VP16 has activity against platinum-resistant EOC.

Prognostic variables in patients with diffuse large-cell lymphoma treated with MACOP-B.

One hundred twenty-six patients with diffuse large-cell lymphoma were treated with methotrexate with leucovorin, doxorubicin, cyclophosphamide, vincristine, prednisone, and bleomycin (MACOP-B) between April 1981 and June 1986. Univariate and multivariate analyses were performed using overall survival as of September 1989 as the end point. Four independent negative predictors of survival were identified: presence of B symptoms; more than two involved lymph node sites; more than one extranodal site (variables related to tumor burden), and age older than 60, a variable related to the patient's ability to tolerate treatment. Each variable contributed the same relative risk of dying and, accordingly, this simple predictive formula was developed empirically: (4-N) x 30 = the approximate percentage of chance of survival at 5 years. "N" is the number of predictive variables present. The same four predictors were also found to be significant by multivariate analysis when only those patients achieving a complete response were analyzed.