Analytical performance of the FDA-cleared Parsortix® PC1 system

Introduction

The Parsortix® PC1 system, Food and Drug Administration (FDA) cleared for use in metastatic breast cancer (MBC) patients, is an epitope-independent microfluidic device for the capture and harvest of circulating tumor cells from whole blood based on cell size and deformability. This report details the analytical characterization of linearity, detection limit, precision, and reproducibility for this device.

Methods

System performance was determined using K2-EDTA blood samples collected from self-declared healthy female volunteers (HVs) and MBC patients spiked with prelabeled cultured breast cancer cell lines (SKBR3, MCF7, or Hs578T). Samples were processed on Parsortix® PC1 systems and captured cells were harvested and enumerated.

Results

The system captured and harvested live SKBR3, MCF7, and Hs578T cells and fixed SKBR3 cells linearly between 2 and ~100 cells, with average harvest rates of 69%, 73%, 79%, and 90%, respectively. To harvest ≥1 cell ≥95% of the time, the system required 3, 5 or 4 live SKBR3, MCF7 or Hs578T cells, respectively. Average harvest rates from precision studies using 5, 10, and ~50 live cells spiked into blood for each cell line ranged from 63.5% to 76.2%, with repeatability and reproducibility percent coefficient of variation (%CV) estimates ranging from 12.3% to 32.4% and 13.3% to 34.1%, respectively. Average harvest rates using ~20 fixed SKBR3 cells spiked into HV and MBC patient blood samples were 75.0% ± 16.1% (%CV = 22.3%) and 68.4% ± 14.3% (%CV = 21.1%), respectively.

Conclusions

These evaluations demonstrate the Parsortix® PC1 system linearly and reproducibly harvests tumor cells from blood over a range of 1 to ~100 cells.

National audit of non-melanoma skin cancer excisions performed by plastic surgery in the UK

A national, multi-centre audit of non-melanoma skin cancer excisions by plastic surgery.

HE4 and CA125 serum biomarker monitoring in women with epithelial ovarian cancer

BACKGROUND

CA125 is the gold standard serum biomarker for monitoring patients with epithelial ovarian cancer (EOC). Human epididymal protein 4 (HE4) is a novel serum biomarker for EOC patients.

OBJECTIVE

The objective of this trial was to examine the utility of measuring serum HE4 levels for monitoring EOC patients and to compare HE4 performance parameters to serum CA125.

METHODS

A retrospective trial using residual longitudinal serum samples drawn during treatment and monitoring from EOC patients. Serum CA125 and HE4 levels were analyzed at each time point, and a velocity of change was calculated and correlated with clinical status. The null hypothesis was that HE4 is inferior to CA125, and this was tested using concordance and two-sided Fisher's exact testing. McNemar's test was used to assess the overall agreement of the two assays with the clinical status.

RESULTS

A total of 129 patients with 272 separate clinical periods and 1739 events (serum samples) were evaluated. Using a 25% change in serum biomarker levels to indicate change in disease status, the accuracy and NPV determined for HE4 versus CA125 were 81.8% versus 82.6% (p = 0.846) and 87.4% versus 89.7% (p = 0.082), respectively. Concordance comparison of HE4 accuracy / CA125 accuracy was 0.990, indicating HE4 was not inferior to CA125 (McNemar's test p-value = 0.522). Performing a velocity of change analysis, the accuracy and NPV determined for HE4 versus CA125 were 78.3% versus 78.6% (p = 0.995) and 74.9% versus 76.3% (p = 0.815), respectively. Concordance comparison of HE4 velocity accuracy / CA125 velocity accuracy was 0.996, again indicating HE4 was not inferior to CA125 (McNemar's test p-value = 0.884). The combination of HE4 and CA125 velocity changes showed a similar accuracy of 81.3% (p = 0.797 compared to HE4 and CA125 alone) and NPV of 81.1% (p≥0.172 compared to HE4 and CA125 alone), and an increased sensitivity of 70.5% (p≤0.070 compared to HE4 and CA125 alone).

CONCLUSION

HE4 is equivalent to CA125 for monitoring of EOC patients. The combination of CA125 and HE4 velocities is superior to either marker alone.

Analysis of serum HE4 levels in various histologic subtypes of epithelial ovarian cancer and other malignant tumors

BACKGROUND: The measurement of serum HE4 levels has emerged as a sensitive and specific biomarker for epithelial ovarian cancers (EOCs). However, serum levels in women diagnosed with various histologic subtypes of EOC and in women with metastatic non-ovarian primary malignancies have not been widely reported. OBJECTIVE: The goal of this study was to identify how serum HE4 levels vary in women diagnosed with different histologic subtypes of EOC and non-ovarian malignancies. METHODS: Data from six prospective pelvic mass clinical trials was combined and an evaluation of serum HE4 levels in women diagnosed with a malignancy was performed. For all patients, serum was obtained prior to surgery and final pathology, including primary tumor site, histologic subtype, grade and stage, were recorded. The mean, median, standard deviation, maximum, and minimum HE4 levels were determined for each group. RESULTS: A total of 984 patients were included in this study, with the average patient age being 60 years old. There were 230 premenopausal and 754 postmenopausal patients. Serum HE4 levels were elevated (≥70.0 pMol) in 85%of EOCs, 40%of LMP tumors, 21%of non-EOCs (germ cell tumors), 25%of cervical cancers, and 47%of non-gynecologic metastatic cancers. Analysis of histologic subtypes revealed 90%(n = 391) of serous, 85%(n = 73) of endometrioid, 45%(n = 42) of mucinous, 86%(n = 51) of mixed tumors, and 69%(n = 36) of clear cell tumors had elevated serum HE4 levels. CONCLUSIONS: Serum HE4 levels are most often elevated in women with high grade serous and endometrioid EOCs, and though serum elevations are seen more often with advanced stage disease, HE4 is also often elevated in early stage disease and lower grade tumors.

Characterization of RNA-Binding Motif 3 (RBM3) Protein Levels and Nuclear Architecture Changes in Aggressive and Recurrent Prostate Cancer

Background

The RNA-binding motif protein 3 (RBM3) has been shown to be up-regulated in several types of cancer, including prostate cancer (PCa), compared to normal tissues. Increased RBM3 nuclear expression has been linked to improved clinical outcomes.

Aims

Given that RBM3 has been hypothesized to play a role in critical nuclear functions such as chromatin remodeling, DNA damage response, and other post-transcriptional processes, we sought to: (1) quantify RBM3 protein levels in archival PCa samples; (2) develop a nuclear morphometric model to determine if measures of RBM3 protein levels and nuclear features could be used to predict disease aggressiveness and biochemical recurrence.

Methods & Results

This study utilized two tissue microarrays (TMAs) stained for RBM3 that included 80 total cases of PCa stratified by Gleason score. A software-mediated image processing algorithm identified RBM3-positive cancerous nuclei in the TMA samples and calculated twenty-two features quantifying RBM3 expression and nuclear architecture. Multivariate logistic regression (MLR) modeling was performed to determine if RBM3 levels and nuclear structural changes could predict PCa aggressiveness and biochemical recurrence (BCR). Leave-one-out cross validation (LOOCV) was used to provide insight on how the predictive capabilities of the feature set might behave with respect to an independent patient cohort to address issues such as model overfitting. RBM3 expression was found to be significantly downregulated in highly aggressive GS ≥ 8 PCa samples compared to other Gleason scores (P < 0.0001) and significantly down-regulated in recurrent PCa samples compared to non-recurrent samples (P = 0.0377). An eleven-feature nuclear morphometric MLR model accurately identified aggressive PCa, yielding a receiver operating characteristic area under the curve (ROC-AUC) of 0.90 (P < 0.0001) in the raw data set and 0.77 (95% CI: 0.83-0.97) for LOOCV testing. The same eleven-feature model was then used to predict recurrence, yielding a ROC-AUC of 0.92 (P = 0.0004) in the raw data set and 0.76 (95% CI: 0.64-0.87) for LOOCV testing.

Conclusions

The RBM3 biomarker alone is a strong prognostic marker for the prediction of aggressive PCa and biochemical recurrence. Further, RBM3 appears to be down-regulated in aggressive and recurrent tumors.

A simple foot pedal device in a horizontal bore imaging facility replicates weightbearing outcomes for Hallux Valgus patients

BACKGROUND

Weightbearing images are important to the diagnosis of foot pathologies as are the three dimensional views available from CT and MRI. Standard three-dimensional imaging hardware, however, does not have a simple tool to obtain weightbearing images. The current research aimed to design, build and test a simple device to apply load in a horizontal bore imaging facility.

METHODS

With the immediate need in hallux valgus studies, hallux valgus subjects were imaged using the new loading device, which could be easily transported and had no additional electronics.

RESULTS

Testing showed that the usual angular measures of the foot (intermetatarsal and hallux valgus) replicated the results from the standard of care standing plain film results. With application of load, HV angle changed from 29.9° non-weightbearing to 32.2° weightbearing, while IM angle changed from nonweightbearing 15.8° to weightbearing 16.5°.

CONCLUSION

The pedal-like device can provide weightbearing images in a horizontal bore MRI facility.

Multiple biomarker algorithms to predict epithelial ovarian cancer in women with a pelvic mass: Can additional makers improve performance?

INTRODUCTION

Management of a woman with a pelvic mass is complicated by difficulty in discriminating malignant from benign disease. Many serum biomarkers have been examined to determine their sensitivity for detecting malignancy. This study was designed to evaluate if the addition of biomarkers to HE4 and CA125, as used in the Risk of Malignancy Algorithm (ROMA), can improve the detection of EOC.

METHODS

This was an IRB approved, prospective clinical trial examining serum obtained from women diagnosed with a pelvic mass who subsequently underwent surgery. Serum biomarker levels for CA125, HE4, YKL-40, transthyretin, ApoA1, Beta-2-microglobulin, transferrin, and LPA were measured. Logistic regression analysis was performed for various marker combinations, ROC curves were generated, and the area under the curves (AUCs) were determined.

RESULTS

A total of 184 patients met inclusion criteria with a median age of 56 years (Range 20-91). Final pathology revealed there were 103 (56.0%) benign tumors, 4 (2.2%) LMP tumors, 61 EOC (33.1%), 2 (1.1%) non-EOC ovarian cancers, 6 (3.3%) gynecologic cancers with metastasis to the ovary and 8 (4.3%) non-gynecologic cancers with metastasis to the ovary. The combination of HE4 and CA125 (i.e. ROMA) achieved an AUC of 91.2% (95% CI: 86.0-96.4) for the detection of EOC vs benign disease. The combination of CA125, HE4, YKL-40, transthyretin, ApoA1, Beta 2 microglobulin, transferrin, LPA and menopausal status achieved the highest AUC of 94.6% (95% CI: 90.1-99.2) but this combination was not significantly better than the HE4 and CA125 combination alone (p = 0.078).

CONCLUSIONS

The addition of select further serum biomarkers to HE4 and CA125 does not add to the performance of the dual marker combination for the detection of ovarian cancer.

The Parsortix™ Cell Separation System-A versatile liquid biopsy platform

Cancer cells from solid tumors can enter the circulatory system and survive to subsequently form distant metastases. The CellSearch® system (Menarini-Silicon Biosystems, Huntingdon Valley, PA) was the first, FDA-cleared system that provided a reliable tool for the investigation of circulating tumor cells (CTCs), which have been shown to be strongly associated with poor survival and therapy failure. Since that time, a number of new technologies have been introduced to improve CTC detection and/or isolation for further characterization. The continued and growing interest in the "liquid biopsy" field has spurred the development of numerous different CTC technologies. However, selecting the most appropriate CTC platform for individual applications can be challenging. No consensus has yet been reached in the community regarding which liquid biopsy technology is optimal. Here, we introduce the Parsortix™ Cell Separation System (ANGLE North America, Inc., King of Prussia, PA), a microfluidic based technology that captures rare cells based on size and deformability, offers reproducibly high capture efficiency, and produces highly enriched, viable (viability dependent on preservative used) CTCs that are amenable to a multitude of downstream analyses, including the isolation and interrogation of single cells. © 2018 The Authors. Cytometry Part A published by Wiley Periodicals, Inc. on behalf of International Society for Advancement of Cytometry.

PBOV1 as a potential biomarker for more advanced prostate cancer based on protein and digital histomorphometric analysis

BACKGROUND

There are few tissue-based biomarkers that can accurately predict prostate cancer (PCa) progression and aggressiveness. We sought to evaluate the clinical utility of prostate and breast overexpressed 1 (PBOV1) as a potential PCa biomarker.

METHODS

Patient tumor samples were designated by Grade Groups using the 2014 Gleason grading system. Primary radical prostatectomy tumors were obtained from 48 patients and evaluated for PBOV1 levels using Western blot analysis in matched cancer and benign cancer-adjacent regions. Immunohistochemical evaluation of PBOV1 was subsequently performed in 80 cancer and 80 benign cancer-adjacent patient samples across two tissue microarrays (TMAs) to verify protein levels in epithelial tissue and to assess correlation between PBOV1 proteins and nuclear architectural changes in PCa cells. Digital histomorphometric analysis was used to track 22 parameters that characterized nuclear changes in PBOV1-stained cells. Using a training and test set for validation, multivariate logistic regression (MLR) models were used to identify significant nuclear parameters that distinguish Grade Group 3 and above PCa from Grade Group 1 and 2 PCa regions.

RESULTS

PBOV1 protein levels were increased in tumors from Grade Group 3 and above (GS 4 + 3 and ≥ 8) regions versus Grade Groups 1 and 2 (GS 3 + 3 and 3 + 4) regions (P = 0.005) as assessed by densitometry of immunoblots. Additionally, by immunoblotting, PBOV1 protein levels differed significantly between Grade Group 2 (GS 3 + 4) and Grade Group 3 (GS 4 + 3) PCa samples (P = 0.028). In the immunohistochemical analysis, measures of PBOV1 staining intensity strongly correlated with nuclear alterations in cancer cells. An MLR model retaining eight parameters describing PBOV1 staining intensity and nuclear architecture discriminated Grade Group 3 and above PCa from Grade Group 1 and 2 PCa and benign cancer-adjacent regions with a ROC-AUC of 0.90 and 0.80, respectively, in training and test sets.

CONCLUSIONS

Our study demonstrates that the PBOV1 protein could be used to discriminate Grade Group 3 and above PCa. Additionally, the PBOV1 protein could be involved in modulating changes to the nuclear architecture of PCa cells. Confirmatory studies are warranted in an independent population for further validation.

Weight-bearing recommendations after first metatarsophalangeal joint arthrodesis fixation: a biomechanical comparison

Background

This study sought to determine whether several metatarsophalangeal (MTP) fusion techniques require complete immobilization or if some level of weight-bearing could be recommended after surgery. A comparison of synthetic composite to actual bone was included in order to examine the validity of the testing conditions.

Methods

Four MTP fusion modalities were tested in synthetic composite bone models: unlocked plating, locked plating, crossed lag screws, and an unlocked plate with a single lag screw. Stiffness was calculated and then used to find the two most rigid constructs; the load to failure was recorded. Stiffness and load to failure testing for the two more rigid constructs in paired cadaveric bones were followed.

Results

The unlocked plate plus screw and crossed screw constructs were stiffest (p < 0.008). Loads to failure of the unlocked plate plus screw and crossed screws in synthetic bone were 131 and 101 N, respectively and in cadaveric bone were 154 and 94 N, respectively, which are less than the estimated 25% body weight required at the MTP joint. The plate plus screws were statistically more stiff than crossed screws (p = 0.008), but there was no statistical difference between synthetic and cadaveric bone in load to failure (p = 0.296).

Conclusions

The plate plus screw offered the greatest stiffness; the failure test showed that no construct could withstand weight-bearing as tolerated; and, synthetic composite models of the MTP joint did not provide the consistent results in stiffness and failure.

Open-label, randomized study of individualized, pharmacokinetically (PK)-guided dosing of paclitaxel combined with carboplatin or cisplatin in patients with advanced non-small-cell lung cancer (NSCLC)

BACKGROUND

Variable chemotherapy exposure may cause toxicity or lack of efficacy. This study was initiated to validate pharmacokinetically (PK)-guided paclitaxel dosing in patients with advanced non-small-cell lung cancer (NSCLC) to avoid supra- or subtherapeutic exposure.

PATIENTS AND METHODS

Patients with newly diagnosed, advanced NSCLC were randomly assigned to receive up to 6 cycles of 3-weekly carboplatin AUC 6 or cisplatin 80 mg/m(2) either with standard paclitaxel at 200 mg/m(2) (arm A) or PK-guided dosing of paclitaxel (arm B). In arm B, initial paclitaxel dose was adjusted to body surface area, age, sex, and subsequent doses were guided by neutropenia and previous-cycle paclitaxel exposure [time above a plasma concentration of 0.05 µM (Tc>0.05)] determined from a single blood sample on day 2. The primary end point was grade 4 neutropenia; secondary end points included neuropathy, radiological response, progression-free survival (PFS) and overall survival (OS).

RESULTS

Among 365 patients randomly assigned, grade 4 neutropenia was similar in both arms (19% versus 16%; P = 0.10). Neuropathy grade ≥2 (38% versus 23%, P < 0.001) and grade ≥3 (9% versus 2%, P < 0.001) was significantly lower in arm B, independent of the platinum drug used. The median final paclitaxel dose was significantly lower in arm B (199 versus 150 mg/m(2), P < 0.001). Response rate was similar in arms A and B (31% versus 27%, P = 0.405), as was adjusted median PFS [5.5 versus 4.9 months, hazard ratio (HR) 1.16, 95% confidence interval (CI) 0.91-1.49, P = 0.228] and OS (10.1 versus 9.5 months, HR 1.05, 95% CI 0.81-1.37, P = 0.682).

CONCLUSION

PK-guided dosing of paclitaxel does not improve severe neutropenia, but reduces paclitaxel-associated neuropathy and thereby improves the benefit-risk profile in patients with advanced NSCLC.

CLINICAL TRIAL INFORMATION

NCT01326767 (https://clinicaltrials.gov/ct2/show/NCT01326767).

A Novel Quantitative Multiplex Tissue Immunoblotting for Biomarkers Predicts a Prostate Cancer Aggressive Phenotype

BACKGROUND

Early prediction of disease progression in men with very low-risk (VLR) prostate cancer who selected active surveillance (AS) rather than immediate treatment could reduce morbidity associated with overtreatment.

METHODS

We evaluated the association of six biomarkers [Periostin, (-5, -7) proPSA, CACNA1D, HER2/neu, EZH2, and Ki-67] with different Gleason scores and biochemical recurrence (BCR) on prostate cancer TMAs of 80 radical prostatectomy (RP) cases. Multiplex tissue immunoblotting (MTI) was used to assess these biomarkers in cancer and adjacent benign areas of 5 μm sections. Multivariate logistic regression (MLR) was applied to model our results.

RESULTS

In the RP cases, CACNA1D, HER2/neu, and Periostin expression were significantly correlated with aggressive phenotype in cancer areas. An MLR model in the cancer area yielded a ROC-AUC = 0.98, whereas in cancer-adjacent benign areas, yielded a ROC-AUC = 0.94. CACNA1D and HER2/neu expression combined with Gleason score in a MLR model yielded a ROC-AUC = 0.79 for BCR prediction. In the small biopsies from an AS cohort of 61 VLR cases, an MLR model for prediction of progressors at diagnosis retained (-5, -7) proPSA and CACNA1D, yielding a ROC-AUC of 0.78, which was improved to 0.82 after adding tPSA into the model.

CONCLUSIONS

The molecular profile of biomarkers is capable of accurately predicting aggressive prostate cancer on retrospective RP cases and identifying potential aggressive prostate cancer requiring immediate treatment on the AS diagnostic biopsy but limited in BCR prediction.

IMPACT

Comprehensive profiling of biomarkers using MTI predicts prostate cancer aggressive phenotype in RP and AS biopsies.

Assessing the risk of ovarian malignancy algorithm for the conservative management of women with a pelvic mass

OBJECTIVE

To evaluate the use of as an aid in the identification of women who can safely undergo conservative, non-surgical management.

METHODS

All patients referred to the Program in Women's Oncology for surgery with a pelvic mass are evaluated at a prospective multidisciplinary tumor board (TB) where ROMA and imaging are used for management recommendations. This study evaluated women presented to TB with a pelvic mass between 2009 and 2013 who had either surgical or conservative management.

RESULTS

Of the 498 patients assessed, 392 (79%) had benign disease, 22 (4%) had LMP tumors, 28 (6%) had stage I-II epithelial ovarian cancer (EOC), 36 (7%) had stage III-IV EOC and 20 (4%) had non-EOC. Using clinical assessment in conjunction with ROMA, the TB recommended observation in 188 (37.8%) women. All patients diagnosed with an invasive malignancy were recommended for surgery by the TB. In the 315 patients managed surgically, 212 were found to have benign disease and 84 women were diagnosed with an invasive malignancy. The sensitivity for the initial TB recommendations using ROMA in conjunction with clinical judgment for detecting malignancy was 100% with a specificity of 47.7% and a NPV of 100%. When including low malignant potential tumors the sensitivity was 99.1%. For stage I-IV EOC ROMA alone had a sensitivity of 95.3%.

CONCLUSIONS

ROMA in conjunction with clinical assessment can safely identify women for conservative management.

Development of circulating tumor cell-endocrine therapy index in patients with hormone receptor-positive breast cancer

BACKGROUND

Endocrine therapy (ET) fails to induce a response in one half of patients with hormone receptor (HR)-positive metastatic breast cancer (MBC), and almost all will eventually become refractory to ET. Circulating tumor cells (CTC) are associated with worse prognosis in patients with MBC, but enumeration alone is insufficient to predict the absolute odds of benefit from any therapy, including ET. We developed a multiparameter CTC-Endocrine Therapy Index (CTC-ETI), which we hypothesize may predict resistance to ET in patients with HR-positive MBC.

METHODS

The CTC-ETI combines enumeration and CTC expression of four markers: estrogen receptor (ER), B-cell lymphoma 2 (BCL-2), Human Epidermal Growth Factor Receptor 2 (HER2), and Ki67. The CellSearch System and reagents were used to capture CTC and measure protein expression by immunofluorescent staining on CTC.

RESULTS

The feasibility of determining CTC-ETI was initially established in vitro and then in a prospective single-institution pilot study in patients with MBC. CTC-ETI was successfully determined in 44 of 50 (88%) patients. Eighteen (41%), 9 (20%), and 17 (39%) patients had low, intermediate, and high CTC-ETI scores, respectively. Interobserver concordance of CTC-ETI determination was from 94% to 95% (Kappa statistic, 0.90-0.91). Inter- and cell-to-cell intrapatient heterogeneity of expression of each of the CTC markers was observed. CTC biomarker expression was discordant from both primary and metastatic tissues.

CONCLUSIONS

CTC expression of ER, BCL-2, HER2, and Ki67 can be reproducibly measured with high analytical validity using the CellSearch System. The clinical implications of CTC-ETI, and of the heterogeneity of CTC biomarker expression, are being evaluated in an ongoing prospective trial.

Monitoring apoptosis and Bcl-2 on circulating tumor cells in patients with metastatic breast cancer

BACKGROUND

Enumeration of circulating tumor cells (CTC) from whole blood permits monitoring of patients with breast carcinoma. Analysis of apoptosis & Bcl-2 expression in CTC might add additional prognostic and predictive information. We estimated the degree of these markers in CTC from patients being treated for metastatic breast cancer.

METHODS

Eighty-three evaluable patients initiating a new therapy for metastatic breast cancer were enrolled. Whole blood was collected at baseline, at one of three short term time windows (24, 48, or 72 h) after initiating treatment, and at first follow-up (3-5 weeks). CTC were isolated, enumerated, and expression of M30 and Bcl2 was determined using the CellSearch(®) System.

RESULTS

At baseline, window, and 3-5 weeks post-treatment, 41/80 (51%), 40/80 (50%) and 21/75 (28%) patients had ≥5 CTC, respectively. At baseline, the proportion of CTC-apoptosis (M30) was inversely correlated with CTC number, and modestly inversely correlated with CTC-Bcl-2. As expected, higher CTC levels at baseline or first follow-up were associated with worse prognosis. Surprisingly, in patients with elevated CTC, higher levels of CTC-apoptosis were associated with worse prognosis, while higher CTC-Bcl-2 levels correlated with better outcomes.

CONCLUSIONS

CTC apoptosis and expression of Bcl-2 can be analytically determined in patients with metastatic breast cancer and may have biological and clinical implications. Characterization of CTC for these and other markers could further increase the utility of CTC monitoring patients in clinical investigations of new anti-neoplastic agents.

Relationship among circulating tumor cells, CEA and overall survival in patients with metastatic colorectal cancer

BACKGROUND

We previously reported results of a prospective trial evaluating the significance of circulating tumor cells (CTCs) in patients with metastatic colorectal cancer (mCRC). This secondary analysis assessed the relationship of the CTC number with carcinoembryonic antigen (CEA) and overall survival.

PATIENTS AND METHODS

Patients with mCRC had CTCs measured at baseline and specific time points after the initiation of new therapy. Patients with a baseline CEA value ≥ 10 ng/ml and CEA measurements within ± 30 days of the CTC collection were included.

RESULTS

We included 217 patients with mCRC who had a CEA value of ≥ 10 ng/ml. Increased baseline CEA was associated with shorter survival (15.8 versus 20.7 months, P = 0.012). Among all patients with a baseline CEA value of ≥ 25 ng/ml, patients with low baseline CTCs (<3, n = 99) had longer survival than those with high CTCs (≥ 3, n = 58; 20.8 versus 11.7 months, P = 0.001). CTCs added prognostic information at the 3-5- and 6-12-week time points regardless of CEA. In a multivariate analysis, CTCs at baseline but not CEA independently predicted survival and both CTCs and CEA independently predicted survival at 6-12 weeks.

CONCLUSIONS

This study demonstrates that both CEA and CTCs contribute prognostic information for patients with mCRC.

Design and implementation of a multichannel millimeter wave interferometer for the Compact Toroidal Hybrid experiment

A three-channel 1 mm wave interferometer has been designed, assembled, and installed on the Compact Toroidal Hybrid torsatron (CTH). The interferometer design makes novel use of a subharmonic mixer for detection, which simplifies alignment. It employs a single electronically tunable source that is repetitively chirped using a sawtooth waveform of frequency up to 1 MHz. The 15.25 GHz drive oscillator is multiplied in two stages to 122 GHz before a final doubler stage brings it to 244 GHz. Local oscillator (LO) power at 122 GHz is directed through waveguide to the LO input of the subharmonic mixer of each viewing chord, simplifying alignment. Phase detection is performed by directly digitizing the amplified mixer outputs at 50 MHz and processing them with a software algorithm. Initial measurements made with the central chord of the new interferometer agree with those from the existing 4 mm system at low densities. The 1 mm system performs well in current-driven discharges reaching densities over 10(19) m(-3), whereas the lower frequency interferometer is found to be less reliable due to loss of fringes. This is a critical improvement for experiments studying the onset, avoidance, and vacuum magnetic transform dependence of disruptions in the CTH device.

Intraosseous hemangioma of the clivus: a case report and review of the literature

Intraosseous hemangiomas are benign vascular tumors that are encountered most commonly in vertebrae and rarely in the skull. When presenting in the skull, they are commonly found in the calvarium in frontal and parietal bones and seldom in the skull base. We encountered a patient with an incidental finding on magnetic resonance imaging (MRI) of an enhancing lesion in the clivus. Here we report an unusual location of a clival intraosseous hemangioma. A 62 year old man worked up for carpal tunnel syndrome had imaging of his cervical spine that revealed an enhancing clival lesion, which extended into the left occipital condyle. Endoscopic endonasal biopsy was performed on the abnormality revealing a capillary hemangioma. Patient tolerated the biopsy well and no further surgical intervention is indicated at this time. Patient will be followed at six month intervals. Primary intraosseus hemangiomas of the skull are extremely rare and usually occur in the calvarium. This is one of the few reported case of an intraosseus hemangioma in the clivus. We present this case in part because it is unusual, but more importantly, with the wider use of MRI, it is likely that these lesions will be discovered more frequently, and conceivably confused for more dangerous lesions.

Expression of inhibin/activin proteins and receptors in the human hypothalamus and basal forebrain

The inhibin/activin family of proteins is known to have a broad distribution of synthesis and expression in many species, as well as a variety of functions in reproductive and other physiological systems. Yet, our knowledge regarding the production and function of inhibin and activin in the central nervous system is relatively limited, especially in humans. The present study aimed to explore the distribution of inhibin/activin protein subunits and receptors in the adult human brain. The human hypothalamus and surrounding basal forebrain was examined using post-mortem tissues from 29 adults. Immunocytochemical studies were conducted with antibodies directed against the inhibin/activin α, βA, and βB subunits, betaglycan and the activin type IIA and IIB receptors. An immunoassay was also utilised to measure dimeric inhibin A and B levels in tissue homogenates of the infundibulum of the hypothalamus. Robust βA subunit immunoreactivity was present in the paraventricular, supraoptic, lateral hypothalamic, infundibular, dorsomedial and suprachiasmatic nuclei of the hypothalamus, in the basal ganglia, and in the nucleus basalis of Meynert. A similar staining distribution was noted for the βB subunit, betaglycan and the type II receptor antibodies, whereas α subunit staining was not detected in any of the major anatomical regions of the human brain. Inhibin B immunoreactivity was present in all tissues, whereas inhibin A levels were below detectable limits. These studies show for the first time that the inhibin/activin protein subunits and receptors can be co-localised in the human brain, implicating potential, diverse neural functions.

Human epididymis protein 4 offers superior specificity in the differentiation of benign and malignant adnexal masses in premenopausal women

OBJECTIVE

We sought to assess the ability of human epididymis protein 4 (HE4) and CA-125 to distinguish among benign, borderline, and malignant pelvic masses in premenopausal women.

STUDY DESIGN

We conducted a subset analysis of data from a prospective clinical trial that enrolled women undergoing surgery for an adnexal mass. Diagnostic performance of CA-125 and HE4 for epithelial ovarian cancer (EOC) detection in premenopausal women was determined.

RESULTS

Of 229 premenopausal patients, 195 (85%) had benign masses, 18 (8%) had EOC, and 16 (7%) had borderline ovarian tumor. The sensitivity of CA-125 and HE4 for EOC detection was 83.3% and 88.9%, respectively. The specificity of CA-125 and HE4 was 59.5% and 91.8%, respectively. A normal HE4 level ruled out invasive cancer in 98% of women with an elevated CA-125.

CONCLUSION

HE4 offers superior specificity compared to CA-125 for the differentiation of benign and malignant adnexal masses in premenopausal women.

Circulating endothelial cells, circulating tumour cells, tissue factor, endothelin-1 and overall survival in prostate cancer patients treated with docetaxel

PURPOSE

We investigated whether serum markers of angiogenesis endothelin-1 (ET-1) and tissue factor (TF), and/or markers of vascular damage such as circulating endothelial cells (CECs), or their relative changes during treatment, were prognostic for overall survival (OS) in castration resistant prostate cancer (CRPC) patients. Additionally, we combined these markers with circulating tumour cells (CTCs) to construct a predictive nomogram for treatment outcome.

PATIENTS AND METHODS

One hundred and sixty two CRPC patients treated with a docetaxel containing regimen had blood drawn before and at 2-5 weeks and 6-8 weeks after treatment start. Prospectively determined CTC and CEC levels, and retrospectively measured serum concentrations of ET-1 (pg/mL) and TF (pg/mL) were evaluated to determine their prognostic value for OS.

RESULTS

Baseline CEC, TF and ET-1 were not prognostic for OS. A > or = 3.8-fold increase in CEC 2-5 weeks after treatment initiation was associated with decreased OS (median 10.9 versus 16.8 months; P=0.015), as was any decrease in TF levels compared to baseline levels (median 11.9 versus 21.5 months; P=0.0005). As previously published, baseline and CTC counts > or = 5 at 2-5 weeks were also predictive of decreased OS. Combining CTC with changes in TF and CEC 2-5 weeks after treatment initiation yielded four groups differing in OS (median OS 24.2 versus 16.0 versus 11.4 versus 6.1 months; P<0.0001).

CONCLUSION

CEC, CTC and TF levels alone and combined can predict early on OS in CRPC patients treated with docetaxel-based therapy. A prospective study to confirm the use of these markers for patient management is needed.

Comparison of a novel multiple marker assay vs the Risk of Malignancy Index for the prediction of epithelial ovarian cancer in patients with a pelvic mass

OBJECTIVE

We sought to compare the Risk of Malignancy Index (RMI) to the Risk of Ovarian Malignancy Algorithm (ROMA) to predict epithelial ovarian cancer (EOC) in women with a pelvic mass.

STUDY DESIGN

In all, 457 women with imaging results from ultrasound, computed tomography, magnetic resonance imaging, and serum HE4 and CA125 determined prior to surgery for pelvic mass were evaluable. RMI values were determined using CA125, imaging score, and menopausal status. ROMA values were determined using HE4, CA125, and menopausal status.

RESULTS

At a set specificity of 75%, ROMA had a sensitivity of 94.3% and RMI had a sensitivity of 84.6% for distinguishing benign status from EOC (P = .0029). In patients with stage I and II disease, ROMA achieved a sensitivity of 85.3% compared with 64.7% for RMI (P < .0001).

CONCLUSION

The dual marker algorithm utilizing HE4 and CA125 to calculate a ROMA value achieves a significantly higher sensitivity for identifying women with EOC than does RMI.

Nuclear roundness variance predicts prostate cancer progression, metastasis, and death: A prospective evaluation with up to 25 years of follow-up after radical prostatectomy

BACKGROUND

Nuclear structure is often altered in cancer due to spatial rearrangements of chromatin organization via activation of oncogenes and other chromatin remodeling genes. Therefore, we evaluated the prognostic value of nuclear roundness variance (NRV) for prostate cancer (PCa) progression, metastasis and PCa-specific death free survivals in a cohort of 116 men after radical prostatectomy (RP).

METHOD

NRV was calculated for each case using the variance of the nuclear roundness from approximately 150 nuclei captured at a magnification of 2,440x for each case in 1992-1993. $${\rm Nuclear}\,{\rm roundness} = {{{\rm Radius}({\rm circumference})} \over {{\rm radius}({\rm area})}} = {R \over r} = {{P/2\pi } \over {\sqrt {A/\pi } }}$$ NRV data were merged with clinical, pathologic, and follow-up data for all patients in 2009. Cox proportional hazards regression and Kaplan-Meier plots were employed to analyze the data.

RESULTS

Median follow-up time after RP for all patients was 19 years (range: 1-25 years, mean: 17 years), with approximately 92% (107/116), 71% (82/116), and 47% (55/116) patients having >or=10, 15, and 20 years of follow-up, respectively. NRV was the most significant parameter for prediction of all three outcomes and its concordance-index (C-Index) increased from progression (0.7080) to metastasis (0.7332) to PCa-specific death (0.8090) free survival predictions. Of note, NRV C-Index was significantly higher compared to Gleason Score C-Index for metastasis (0.7332 vs. 0.6046; P = 0.027) and PCa-specific death (0.8090 vs. 0.6336; P = 0.004) free survival predictions. However, the difference between NRV and Gleason Score C-Indexes was not statistically significant for progression free survival prediction (0.7080 vs. 0.6463; P = 0.106).

CONCLUSION

NRV is valuable nuclear structural feature that exceeds Gleason score to predict an aggressive phenotype of PCa.

Significance of Circulating Tumor Cells Detected by the CellSearch System in Patients with Metastatic Breast Colorectal and Prostate Cancer

The increasing number of treatment options for patients with metastatic carcinomas has created a concomitant need for new methods to monitor their use. Ideally, these modalities would be noninvasive, be independent of treatment, and provide quantitative real-time analysis of tumor activity in a variety of carcinomas. Assessment of circulating tumor cells (CTCs) shed into the blood during metastasis may satisfy this need. We developed the CellSearch System to enumerate CTC from 7.5 mL of venous blood. In this review we compare the outcomes from three prospective multicenter studies investigating the use of CTC to monitor patients undergoing treatment for metastatic breast (MBC), colorectal (MCRC), or prostate cancer (MPC) and review the CTC definition used in these studies. Evaluation of CTC at anytime during the course of disease allows assessment of patient prognosis and is predictive of overall survival.

Circulating tumour cells early predict progression-free and overall survival in advanced colorectal cancer patients treated with chemotherapy and targeted agents

BACKGROUND

Early predictive markers for response are needed for advanced colorectal cancer (ACC) patients. We assessed the value of circulating tumour cells (CTC) in ACC patients treated with chemotherapy plus targeted agents (CAIRO2 phase III trial) and compared the results with computed tomography (CT) imaging.

MATERIALS AND METHODS

CTC were determined at baseline and at different time points during treatment. Patients were stratified into low (less than three CTC per 7.5 ml of blood) or high CTC (three or more CTC per 7.5 ml of blood).

RESULTS

A total of 467 patients were assessable for CTC analysis. Among them, 129 patients (29%) with high baseline CTC had a significantly decreased progression-free survival [PFS; hazard ratio (HR) 1.5] and overall survival (OS; HR 2.2) compared with 322 patients with low baseline CTC. This difference remained statistically significant during treatment. The sensitivity and specificity of high CTC at baseline for the prediction of progressive disease on CT imaging were 16.7% and 70.1%, respectively, and of high CTC at 1-2 weeks after the start of treatment 20.0% and 95.1%, respectively. The combined analysis of CTC and CT imaging provided a more accurate outcome assessment than either modality alone.

CONCLUSIONS

The CTC count before and during treatment independently predicts PFS and OS in ACC patients treated with chemotherapy plus targeted agents and provides additional information to CT imaging.

Circulating tumor cells and [18F]fluorodeoxyglucose positron emission tomography/computed tomography for outcome prediction in metastatic breast cancer

PURPOSE

Circulating tumor cells (CTCs) and [(18)F]fluorodeoxyglucose (FDG) positron emission tomography (PET)/computed tomography (CT) are two new promising tools for therapeutic monitoring. In this study, we compared the prognostic value of CTC and FDG-PET/CT monitoring during systemic therapy for metastatic breast cancer (MBC).

PATIENTS AND METHODS

A retrospective analyses of 115 MBC patients who started a new line of therapy and who had CTC counts and FDG-PET/CT scans performed at baseline and at 9 to 12 weeks during therapy (midtherapy) was performed. Patients were categorized according to midtherapy CTC counts as favorable (ie, < five CTCs/7.5 mL blood) or unfavorable (> or = five CTCs/7.5 mL blood) outcomes. CTC counts and FDG-PET/CT response at midtherapy were compared, and univariate and multivariate analyses were performed to identify factors associated with survival.

RESULTS

In 102 evaluable patients, the median overall survival time was 14 months (range, 1 to > 41 months). Midtherapy CTC levels correlated with FDG-PET/CT response in 68 (67%) of 102 evaluable patients. In univariate analysis, midtherapy CTC counts and FDG-PET/CT response predicted overall survival (P < .001 and P = .001, respectively). FDG-PET/CT predicted overall survival (P = .0086) in 31 (91%) of 34 discordant patients who had fewer than five CTCs at midtherapy. Only midtherapy CTC levels remained significant in a multivariate analysis (P = .004).

CONCLUSION

Detection of five or more CTCs during therapeutic monitoring can accurately predict prognosis in MBC beyond metabolic response. FDG-PET/CT deserves a role in patients who have fewer than five CTCs at midtherapy. Prospective trials should evaluate the most sensitive and cost-effective modality for therapeutic monitoring in MBC.

Prognostic significance of circulating tumor cells in patients with metastatic colorectal cancer

BACKGROUND

We demonstrated that circulating tumor cell (CTC) number at baseline and follow-up is an independent prognostic factor in metastatic colorectal cancer (mCRC). This analysis was undertaken to explore whether patient and treatment characteristics impact the prognostic value of CTCs.

PATIENTS AND METHODS

CTCs were enumerated with immunomagnetic separation from the blood of 430 patients with mCRC at baseline and on therapy. Patients were stratified into unfavorable and favorable prognostic groups based on CTC levels of > or = 3 or <3 CTCs/7.5 ml, respectively. Subgroups were analyzed by line of treatment, liver involvement, receipt of oxaliplatin, irinotecan, or bevacizumab, age, and Eastern Cooperative Oncology Group performance status (ECOG PS).

RESULTS

Seventy-one percent of deaths have occurred. Median follow-up for living patients is 25.8 months. For all patients, progression-free survival (PFS) and overall survival (OS) for unfavorable compared with favorable baseline CTCs is shorter (4.4 versus 7.8 m, P = 0.004 for PFS; 9.4 versus 20.6 m, P < 0.0001 for OS). In all patient subgroups, unfavorable baseline CTC was associated with inferior OS (P < 0.001). In patients receiving first- or second-line therapy (P = 0.003), irinotecan (P = 0.0001), having liver involvement (P = 0.002), >/=65 years (P = 0.0007), and ECOG PS of zero (P = 0.04), unfavorable baseline CTC was associated with inferior PFS.

CONCLUSION

Baseline CTC count is an important prognostic factor within specific subgroups defined by treatment or patient characteristics.

An instrument for combining x-ray multiple diffraction and x-ray topographic imaging for examining crystal microcrystallography and perfection

Diffraction imaging using x-ray topography (XRT) and x-ray multiple diffraction (XRMD) provide valuable tools for examining the growth defects in crystals and the distributions from ideal lattice symmetry (microcrystallography). The topographic x-ray multiple diffraction microprobe (TMDM) combines the complementary aspects of both techniques enabling XRT and XRMD studies within the same instrument providing a useful resource for the structural characterization of materials that are not very stable in vacuum and electron beam environments. The design of the TMDM instrument is described together with data taken on GaAs (001) and potassium dihydrogen phosphate (001).

DNA Ploidy as surrogate for biopsy gleason score for preoperative organ versus nonorgan-confined prostate cancer prediction

OBJECTIVES

Transformation of normal epithelium into cancer cells involves epigenetic and genetic changes and modifications in nuclear structure and tissue architecture. To evaluate nuclear morphometric alterations and clinicopathologic features for organ- vs nonorgan-confined prostate carcinoma (PCa) prediction.

METHODS

Of 557 prospectively enrolled patients, 370 had complete information and sufficient tumor area for all evaluated parameters (281 organ-confined and 89 nonorgan-confined PCa cases). Digital images of Feulgen DNA-stained nuclei were captured from biopsies using the AutoCyte imaging system, and the nuclear morphometric alterations were calculated. Logistic regression analysis with bootstrap resampling was used to determine the factors important for differentiation of the 2 groups and to generate models for organ- vs nonorgan-confined PCa prediction.

RESULTS

Several nuclear morphometric features were significantly altered and could differentiate organ- and nonorgan-confined disease. DNA ploidy was the most important factor among the significant nuclear morphometric features and was the second most important factor for organ- vs nonorgan-confined PCa prediction when considered with total prostate-specific antigen (PSA), complexed PSA, free/total PSA, biopsy Gleason score, and clinical stage. The combination of DNA ploidy with clinical stage, total PSA, and biopsy Gleason score showed an improvement of 1.5% in the area under the receiver operator characteristic curves compared with the combination of clinical stage, total PSA, and biopsy Gleason (73.97% vs 72.43%). The use of DNA ploidy in lieu of the biopsy Gleason score in each preoperative model evaluated resulted in equivalent or improved organ- vs nonorgan-confined PCa prediction.

CONCLUSIONS

The results of our study have shown that DNA ploidy can serve as a surrogate biomarker that has the potential to replace biopsy Gleason scores for organ- vs nonorgan-confined PCa prediction.

Long-term assessment of prostate cancer progression free survival: evaluation of pathological parameters, nuclear shape and molecular biomarkers of pathogenesis

BACKGROUND

Molecular pathways of proliferation, angiogenesis, neuroendocrine differentiation, apoptosis and alterations in nuclear structure of cancer epithelial cells are important in the pathogenesis of prostate cancer (PCa). Therefore, we evaluated the prognostic value of these parameters in 105 clinically localized PCa tumors with long-term follow-up after radical prostatectomy for progression-free survival (PFS).

METHOD

Nuclear roundness variance (NRV) was calculated for tumor nuclei using the graphic tracing DynaCELL system. Immunohistochemistry assessed expression of Ki67, PCNA (proliferation), Chromogranin A (neuroendocrine differentiation), CD31 (angiogenesis), BCL2 (apoptosis), and Her-2/neu (oncogene) in the tumors. Cox proportional hazards regression, Spearman's rank correlation, and Kaplan-Meier plots were employed to analyze the data.

RESULTS

Gleason score, focal vs. non-focal extra-prostatic extension, organ confined status, NRV, Her-2/neu, CD-31 and Ki67 were univariately significant predictors of PFS. NRV was the most significant prognostic indicator with the highest concordance index (0.7) for PFS. Gleason score, NRV and Her-2/neu were multivariately significant and yielded a concordance index of 0.77.

CONCLUSION

Her-2/neu oncogene and NRV were shown to be significant in the prediction of PFS. The assessment of alterations in nuclear structure using NRV proved to be the most significant factor in the prediction of PFS. Integration of image analysis-based NRV and molecular biomarkers with pathologic parameters should be considered for validation in the prediction of PFS.

Circulating tumor cells predict survival benefit from treatment in metastatic castration-resistant prostate cancer

PURPOSE

A method for enumerating circulating tumor cells (CTC) has received regulatory clearance. The primary objective of this prospective study was to establish the relationship between posttreatment CTC count and overall survival (OS) in castration-resistant prostate cancer (CRPC). Secondary objectives included determining the prognostic utility of CTC measurement before initiating therapy, and the relationship of CTC to prostate-specific antigen (PSA) changes and OS at these and other time points.

EXPERIMENTAL DESIGN

Blood was drawn from CRPC patients with progressive disease starting a new line of chemotherapy before treatment and monthly thereafter. Patients were stratified into predetermined Favorable or Unfavorable groups (<5 and > or =5 CTC/7.5mL).

RESULTS

Two hundred thirty-one of 276 enrolled patients (84%) were evaluable. Patients with Unfavorable pretreatment CTC (57%) had shorter OS (median OS, 11.5 versus 21.7 months; Cox hazard ratio, 3.3; P < 0.0001). Unfavorable posttreatment CTC counts also predicted shorter OS at 2 to 5, 6 to 8, 9 to 12, and 13 to 20 weeks (median OS, 6.7-9.5 versus 19.6-20.7 months; Cox hazard ratio, 3.6-6.5; P < 0.0001). CTC counts predicted OS better than PSA decrement algorithms at all time points; area under the receiver operator curve for CTC was 81% to 87% and 58% to 68% for 30% PSA reduction (P = 0.0218). Prognosis for patients with (a) Unfavorable baseline CTC who converted to Favorable CTC improved (6.8 to 21.3 months); (b) Favorable baseline CTC who converted to Unfavorable worsened (>26 to 9.3 months).

CONCLUSIONS

CTC are the most accurate and independent predictor of OS in CRPC. These data led to Food and Drug Administration clearance of this assay for the evaluation of CRPC.

A novel multiple marker bioassay utilizing HE4 and CA125 for the prediction of ovarian cancer in patients with a pelvic mass

INTRODUCTION

Patients diagnosed with epithelial ovarian cancer (EOC) have improved outcomes when cared for at centers experienced in the management of EOC. The objective of this trial was to validate a predictive model to assess the risk for EOC in women with a pelvic mass.

METHODS

Women diagnosed with a pelvic mass and scheduled to have surgery were enrolled on a multicenter prospective study. Preoperative serum levels of HE4 and CA125 were measured. Separate logistic regression algorithms for premenopausal and postmenopausal women were utilized to categorize patients into low and high risk groups for EOC.

RESULTS

Twelve sites enrolled 531 evaluable patients with 352 benign tumors, 129 EOC, 22 LMP tumors, 6 non EOC and 22 non ovarian cancers. The postmenopausal group contained 150 benign cases of which 112 were classified as low risk giving a specificity of 75.0% (95% CI 66.9-81.4), and 111 EOC and 6 LMP tumors of which 108 were classified as high risk giving a sensitivity of 92.3% (95% CI=85.9-96.4). The premenopausal group had 202 benign cases of which 151 were classified as low risk providing a specificity of 74.8% (95% CI=68.2-80.6), and 18 EOC and 16 LMP tumors of which 26 were classified as high risk, providing a sensitivity of 76.5% (95% CI=58.8-89.3).

CONCLUSION

An algorithm utilizing HE4 and CA125 successfully classified patients into high and low risk groups with 93.8% of EOC correctly classified as high risk. This model can be used to effectively triage patients to centers of excellence.

Probes for measuring fluctuation-induced Maxwell and Reynolds stresses in the edge of the Madison Symmetric Torus reversed field pinch

Several probes have been constructed to measure fluctuation-induced Maxwell and Reynolds stresses in the edge of the Madison Symmetric Torus reversed field pinch (RFP). The magnetic probe is composed of six magnetic pickup coil triplets. The triplets are separated spatially, which allows for local measurements of the Maxwell stress. To measure the plasma flow components for evaluation of the Reynolds stress, we employ a combination of an optical probe [Kuritsyn et al., Rev. Sci. Indrum. 77, 10F112 (2006)] and a Mach probe. The optical probe measures the radial ion flow locally using Doppler spectroscopy. The Mach probe consists of four current collectors biased negatively with respect to a reference tip and allows for measurements of the poloidal and toroidal components of the bulk plasma flow. The stresses are observed to play an important role in the momentum balance in the RFP edge during internal reconnection events.

Relationship of circulating tumor cells to tumor response, progression-free survival, and overall survival in patients with metastatic colorectal cancer

PURPOSE

As treatment options expand for metastatic colorectal cancer (mCRC), a blood marker with a prognostic and predictive role could guide treatment. We tested the hypothesis that circulating tumor cells (CTCs) could predict clinical outcome in patients with mCRC.

PATIENTS AND METHODS

In a prospective multicenter study, CTCs were enumerated in the peripheral blood of 430 patients with mCRC at baseline and after starting first-, second-, or third-line therapy. CTCs were measured using an immunomagnetic separation technique.

RESULTS

Patients were stratified into unfavorable and favorable prognostic groups based on CTC levels of three or more or less than three CTCs/7.5 mL, respectively. Patients with unfavorable compared with favorable baseline CTCs had shorter median progression-free survival (PFS; 4.5 v 7.9 months; P = .0002) and overall survival (OS; 9.4 v 18.5 months; P < .0001). Differences persisted at 1 to 2, 3 to 5, 6 to 12, and 13 to 20 weeks after therapy. Conversion of baseline unfavorable CTCs to favorable at 3 to 5 weeks was associated with significantly longer PFS and OS compared with patients with unfavorable CTCs at both time points (PFS, 6.2 v 1.6 months; P = .02; OS, 11.0 v 3.7 months; P = .0002). Among nonprogressing patients, favorable compared with unfavorable CTCs within 1 month of imaging was associated with longer survival (18.8 v 7.1 months; P < .0001). Baseline and follow-up CTC levels remained strong predictors of PFS and OS after adjustment for clinically significant factors.

CONCLUSION

The number of CTCs before and during treatment is an independent predictor of PFS and OS in patients with metastatic colorectal cancer. CTCs provide prognostic information in addition to that of imaging studies.

Relationship of circulating tumor cells to tumor response, progression-free survival, and overall survival in patients with metastatic colorectal cancer

PURPOSE

As treatment options expand for metastatic colorectal cancer (mCRC), a blood marker with a prognostic and predictive role could guide treatment. We tested the hypothesis that circulating tumor cells (CTCs) could predict clinical outcome in patients with mCRC.

PATIENTS AND METHODS

In a prospective multicenter study, CTCs were enumerated in the peripheral blood of 430 patients with mCRC at baseline and after starting first-, second-, or third-line therapy. CTCs were measured using an immunomagnetic separation technique.

RESULTS

Patients were stratified into unfavorable and favorable prognostic groups based on CTC levels of three or more or less than three CTCs/7.5 mL, respectively. Patients with unfavorable compared with favorable baseline CTCs had shorter median progression-free survival (PFS; 4.5 v 7.9 months; P = .0002) and overall survival (OS; 9.4 v 18.5 months; P < .0001). Differences persisted at 1 to 2, 3 to 5, 6 to 12, and 13 to 20 weeks after therapy. Conversion of baseline unfavorable CTCs to favorable at 3 to 5 weeks was associated with significantly longer PFS and OS compared with patients with unfavorable CTCs at both time points (PFS, 6.2 v 1.6 months; P = .02; OS, 11.0 v 3.7 months; P = .0002). Among nonprogressing patients, favorable compared with unfavorable CTCs within 1 month of imaging was associated with longer survival (18.8 v 7.1 months; P < .0001). Baseline and follow-up CTC levels remained strong predictors of PFS and OS after adjustment for clinically significant factors.

CONCLUSION

The number of CTCs before and during treatment is an independent predictor of PFS and OS in patients with metastatic colorectal cancer. CTCs provide prognostic information in addition to that of imaging studies.

Using nuclear morphometry to predict the need for treatment among men with low grade, low stage prostate cancer enrolled in a program of expectant management with curative intent

PURPOSE

We assessed the use of quantitative clinical and pathologic information to predict which patients would eventually require treatment for prostate cancer (CaP) in an expectant management (EM) cohort.

EXPERIMENTAL DESIGN

We identified 75 men having prostate cancer with favorable initial biopsy characteristics; 30 developed an unfavorable biopsy (Gleason grade >6, >2 cores with cancer, >50% of a core with cancer, or a palpable nodule) requiring treatment and 45 maintained favorable biopsies throughout a median follow-up of 2.7 years. Demographic, clinical data and quantitative tissue histomorphometry determined by digital image analysis were analyzed.

RESULTS

Logistic regression (LR) modeling generated a quantitative nuclear grade (QNG) signature based on the enrollment biopsy for differentiation of Favorable and Unfavorable groups using a variable LR selection criteria of P(z)<0.05. The QNG signature utilized 12 nuclear morphometric descriptors (NMDs) and had an area under the receiver operator characteristic curve (ROC-AUC) of 87% with a sensitivity of 82%, specificity of 70% and accuracy of 75%. A multivariable LR model combining QNG signature with clinical and pathological variables yielded an AUC-ROC of 88% and a sensitivity of 81%, specificity of 78% and accuracy of 79%. A LR model using prostate volume, PSA density, and number of pre-diagnosis biopsies resulted in an AUC-ROC of 68% and a sensitivity of 85%, specificity of 37% and accuracy of 56%.

CONCLUSIONS

QNG using EM prostate biopsies improves the predictive accuracy of LR models based on traditional clinicopathologic variables in determining which patients will ultimately develop an unfavorable biopsy. Our QNG-based model must be rigorously, prospectively validated prior to use in the clinical arena.

Statistical considerations for enumeration of circulating tumor cells

BACKGROUND

Circulating tumor cells (CTCs) in patients with carcinomas are extremely rare. In metastatic breast cancer, the presence of >or=5 CTCs in 7.5 ml of blood has been associated with short survival. As this threshold has clinical implications, it is important to recognize the limitations associated with the detection and enumeration of CTCs.

METHODS

Statistical analyses were performed on data generated from a multi-center clinical trial that utilized the CellSearchtrade mark System to isolate and enumerate CTCs in 7.5 ml blood samples. The statistical issues associated with each step of the process, from blood collection to final image analysis and CTC enumeration, were determined and implemented into a model.

RESULTS

A model describing the statistics of the different process steps that are needed for the isolation and detection of CTCs was developed. The model uses the Poisson distribution for blood collection and empirically determined distributions for the isolation and identification of CTCs. The variability between readers was identified as one of the main sources of errors responsible for the current threshold level of five CTCs.

CONCLUSIONS

Elimination of the errors made in the identification of tumor cells isolated from 7.5 ml of blood could potentially reduce the CTC threshold for the identification of patients with a poor prognosis from the current value of five CTCs to one CTC per 7.5 ml of blood.

Endothelial cells in peripheral blood of healthy subjects and patients with metastatic carcinomas

BACKGROUND

A lack of standardized assays and consensus of cell definition has lead to a wide variation in the reported range of circulating endothelial cells (CECs).

METHODS

An automated rare cell analysis system was used to enumerate nucleated, CD146+/CD105+/CD45- CECs in 4 mL of blood.

RESULTS

Recoveries of spiked HUVECs were linear over a range of 0-1,241 cells (R2>or=0.99) with recoveries of >or=70% at each spike level. Correlation coefficient values for interoperator variability and duplicate sample variation were (R2=0.99 and 0.90), respectively. Correlation of CEC counts between tubes 1-2 and 2-3 drawn from the same subject in sequence differed (R2=0.48 and 0.63, respectively). The normal CEC reference range established in 249 healthy donors was 1-20 CECs/mL blood. CEC counts were significantly higher in the 206 metastatic carcinoma patients (P<0.0001).

CONCLUSION

CECs can be accurately and reproducibly enumerated in blood and are elevated in metastatic carcinomas compared with healthy donors. Phlebotomy procedures can affect endothelial cell counts.

MESOMARK: a potential test for malignant pleural mesothelioma

BACKGROUND

Soluble mesothelin-related peptides (SMRP)have been reported to be potential biomarkers for malignant pleural mesothelioma (MPM). We report analytical and preliminary clinical studies of MESOMARK, a quantitative assay for SMRP.

METHODS

The MESOMARK assay is a 2-step immunoenzymatic assay in an ELISA format with a 6-point calibration curve (0-32 nmol/L). We assessed analytical imprecision, analyte stability, and analytical interferences. We measured SMRP by this assay in 409 apparently healthy individuals (reference interval study), 177 patients with nonmalignant conditions, and 500 cancer patients, including 88 with MPM.

RESULTS

The limit of detection was 0.16 nmol/L. At 2-19 nmol/L, intraassay imprecision (CV) was 1.1%-5.3%, and total imprecision was 4.0%-11.0%. The mean dilution recovery for 5 samples was 109% (range, 99%-113%). No interference was seen from added bilirubin (200 mg/L), hemoglobin (500 mg/L), triglycerides (30 g/L), chemotherapeutic agents, or other tested substances. Recombinant mesothelin was stable in serum upon freeze/thaw at -70 degrees C and upon storage for at least 7 days at 2-8 degrees C. The 99(th) percentile of the reference group was 1.5 nmol/L [95% confidence interval (CI), 1.2-1.6 nmol/L; n = 409], and mean SMRP was significantly higher in sera from patients with MPM (7.5 nmol/L; 95% CI, 2.8-12.1 nmol/L; n = 88). SMRP was increased in 52% and 5% of MPM patients and asbestos-exposed individuals, respectively. Concentrations in other nonmalignant and malignant conditions were similar to those in healthy controls.

CONCLUSIONS

The MESOMARK assay is analytically robust and may be useful for the detection and management of mesothelioma.

Circulating tumor cells at each follow-up time point during therapy of metastatic breast cancer patients predict progression-free and overall survival

PURPOSE

We reported previously that >or=5 circulating tumor cells (CTC) in 7.5 mL blood at baseline and at first follow-up in 177 patients with metastatic breast cancer (MBC) were associated with poor clinical outcome. In this study, additional follow-up data and CTC levels at subsequent follow-up visits were evaluated.

EXPERIMENTAL DESIGN

CTCs were enumerated in 177 MBC patients before the initiation of a new course of therapy (baseline) and 3 to 5, 6 to 8, 9 to 14, and 15 to 20 weeks after the initiation of therapy. Progression-free survival (PFS) and overall survival (OS) times were calculated from the dates of each follow-up blood draw. Kaplan-Meier plots and survival analyses were done using a threshold of >or=5 CTCs/7.5 mL at each blood draw.

RESULTS

Median PFS times for patients with <5 CTC from each of the five blood draw time points were 7.0, 6.1, 5.6, 7.0, and 6.0 months, respectively. For patients with >or=5 CTC, median PFS from these same time points was significantly shorter: 2.7, 1.3, 1.4, 3.0, and 3.6 months, respectively. Median OS for patients with <5 CTC from the five blood draw time points was all >18.5 months. For patients with >or=5 CTC, median OS from these same time points was significantly shorter: 10.9, 6.3, 6.3, 6.6, and 6.7 months, respectively. Median PFS and OS times at baseline and up to 9 to 14 weeks after the initiation of therapy were statistically significantly different.

CONCLUSIONS

Detection of elevated CTCs at any time during therapy is an accurate indication of subsequent rapid disease progression and mortality for MBC patients.

Circulating tumor cells versus imaging--predicting overall survival in metastatic breast cancer

PURPOSE

The presence of >or=5 circulating tumor cells (CTC) in 7.5 mL blood from patients with measurable metastatic breast cancer before and/or after initiation of therapy is associated with shorter progression-free and overall survival. In this report, we compared the use of CTCs to radiology for prediction of overall survival.

EXPERIMENTAL DESIGN

One hundred thirty-eight metastatic breast cancer patients had imaging studies done before and a median of 10 weeks after the initiation of therapy. All scans were centrally reviewed by two independent radiologists using WHO criteria to determine radiologic response. CTC counts were determined approximately 4 weeks after initiation of therapy. Specimens were analyzed at one of seven laboratories and reviewed by a central laboratory.

RESULTS

Interreader variability for radiologic responses and CTC counts were 15.2% and 0.7%, respectively. The median overall survival of 13 (9%) patients with radiologic nonprogression and >or=5 CTCs was significantly shorter than that of the 83 (60%) patients with radiologic nonprogression and <5 CTCs (15.3 versus 26.9 months; P=0.0389). The median overall survival of the 20 (14%) patients with radiologic progression and <5 CTCs was significantly longer than the 22 (16%) patients with >or=5 CTCs that showed progression by radiology (19.9 versus 6.4 months; P=0.0039).

CONCLUSIONS

Assessment of CTCs is an earlier, more reproducible indication of disease status than current imaging methods. CTCs may be a superior surrogate end point, as they are highly reproducible and correlate better with overall survival than do changes determined by traditional radiology.

Alterations in nuclear structure and expression of proPSA predict differences between native Japanese and Japanese-American prostate cancer

OBJECTIVES

To differentiate the benign and/or malignant epithelial cells in prostate cancer (PCa) glands of native Japanese (NJ) and Japanese-American (JA) men using biomarkers.

METHODS

Tissue microarrays from radical prostatectomy specimens of cancerous and adjacent benign areas from 25 NJ and 25 JA prostate glands were studied. Image analysis was used to quantify total prostate-specific antigen (PSA) and proPSA immunohistochemical staining, as well as the variance of several morphometric features from Feulgen-stained epithelial cell nuclei. Logistic regression analysis was applied to determine whether quantitative nuclear grade (QNG) calculations and PSA immunohistochemical staining could differentiate the two test groups.

RESULTS

The QNG model differentiated changes in the benign epithelium of the two Japanese groups with an area under the receiver operating characteristic curve of 84% and accuracy of 82% (P = 0.0001). A second QNG model differentiated changes in the malignant epithelium of the two groups with an area under the receiver operating characteristic curve of 84% and accuracy of 76% (P = 0.0023). Logistic regression models combining proPSA immunohistochemical data and QNG from either benign or malignant tissue components yielded areas under the receiver operating characteristic curve of 96% and 91% (P <0.0001) for differentiation of the JA and NJ groups, respectively.

CONCLUSIONS

Unique nuclear morphometric alterations demonstrated by QNG combined with proPSA immunohistologic localization independently predicted for significant differences between NJ and JA men with PCa. These preliminary observations indicate a basis for biologic and molecular alterations in the benign adjacent and malignant epithelium between these two groups.

Circulating tumor cells predict survival in patients with metastatic prostate cancer

OBJECTIVES

To determine whether circulating tumor cells (CTCs) predict for survival in patients with metastatic prostate cancer (PCa) and to compare its prognostic abilities with other clinical factors.

METHODS

Blood samples from 37 patients with metastatic PCa were analyzed for CTCs. CTCs were enriched from 7.5 mL blood using magnetic nanoparticles targeting the epithelial cell adhesion molecule and then fluorescently labeled. The samples were analyzed by multiparameter flow cytometry, and events with appropriate light scatter properties that were nucleic acid dye positive, cytokeratin positive, and CD45 negative were defined as CTCs.

RESULTS

The number of CTCs found ranged from 0 to 8586 per 7.5 mL (mean 530 +/- 1887, median 5). A threshold of 5 or more CTCs per 7.5 mL of blood was used to evaluate the ability of CTCs to predict for overall survival. Of the 37 patients, 23 (62%) had 5 or more CTCs, with a median overall survival of 0.70 year compared with more than 4 years for those patients with fewer than 5 CTCs (log-rank P = 0.002, Cox hazards ratio 7.4). In the subset of 26 patients with hormone-refractory PCa, the presence of CTCs was the most significant parameter predictive of survival in univariate and multivariate analyses.

CONCLUSIONS

In this pilot study, the presence of 5 or more CTCs in 7.5 mL blood was associated with poor overall survival in patients with metastatic PCa.

Global gene expression profiling of circulating tumor cells

Metastases from primary tumors are responsible for most cancer deaths. It has been shown that circulating tumor cells (CTCs) can be detected in the peripheral blood of patients with a variety of metastatic cancers and that the presence of these cells is associated with poor clinical outcomes. Characterization of CTCs in metastatic cancer patients could provide additional information to augment management of the disease. Here, we describe a novel approach for the identification of molecular markers to detect and characterize CTCs in peripheral blood. Using an integrated platform to immunomagnetically isolate and immunofluorescently detect CTCs, we obtained blood containing > or = 100 CTCs from one metastatic colorectal, one metastatic prostate, and one metastatic breast cancer patient. Using the RNA extracted from the CTC-enriched portion of the sample and comparing it with the RNA extracted from the corresponding CTC-depleted portion, for the first time, global gene expression profiles from CTCs were generated and a list of cancer-specific, CTC-specific genes was obtained. Subsequently, samples immunomagnetically enriched for CTCs from 74 metastatic cancer patients and 50 normal donors were used to confirm by quantitative real-time reverse transcription-PCR CTC-specific expression of selected genes and to show that gene expression profiles for CTCs may be used to distinguish normal donors from advanced cancer patients as well as to differentiate among the three different metastatic cancers. Genes such as AGR2, S100A14, S100A16, FABP1, and others were found useful for detection of CTCs in peripheral blood of advanced cancer patients.

Expression of epithelial cell adhesion molecule in carcinoma cells present in blood and primary and metastatic tumors

The epithelial cell adhesion molecule (EpCAM) is involved in homophilic cell-cell adhesion in normal epithelia and is frequently overexpressed in primary and metastatic adenocarcinomas. It has been postulated that during detachment and dissemination of tumor cells, EpCAM may be down-regulated. Circulating tumor cells (CTC) may demonstrate this phenomenon as they have successfully escaped their local microenvironment and entered the circulation. EpCAM expression of CTC was compared to tumor cells in paraffin-embedded tissue arrays containing various benign diseases and carcinomas. EpCAM expression on CTC was determined by flow cytometry (FCM) and by immunohistochemistry (IHC) in paraffin-embedded tissue. To permit comparison of FCM results to those derived by IHC, EpCAM was quantified on cancer cell lines by FCM and then paraffin-embedded cell-blocks of these lines were used as staining guides for IHC analysis of tissue arrays. By IHC, 97% (384/397) of solid tissues analyzed had detectable EpCAM, with 72% of tissues showing antigen expression levels of > or =400,000 EpCAM molecules per cell. FCM analysis of CTC from 100 metastatic carcinoma patients with > or =2 CTC/90 microl blood showed EpCAM expression ranging from 9,900 to 246,000 (mean 49,700) antigens per cell. EpCAM expression was approximately 10-fold lower on CTC as compared to primary and metastatic tissues, suggesting that EpCAM expression is transient and dependent upon the local micro-environment. This supports the hypothesis that this adhesion molecule is down-regulated on carcinoma cells in the circulation.

Tumor cells circulate in the peripheral blood of all major carcinomas but not in healthy subjects or patients with nonmalignant diseases

PURPOSE

The purpose of this study was to determine the accuracy, precision, and linearity of the CellSearch system and evaluate the number of circulating tumor cells (CTCs) per 7.5 mL of blood in healthy subjects, patients with nonmalignant diseases, and patients with a variety of metastatic carcinomas.

EXPERIMENTAL DESIGN

The CellSearch system was used to enumerate CTCs in 7.5 mL of blood. Blood samples spiked with cells from tumor cell lines were used to establish analytical accuracy, reproducibility, and linearity. Prevalence of CTCs was determined in blood from 199 patients with nonmalignant diseases, 964 patients with metastatic carcinomas, and 145 healthy donors.

RESULTS

Enumeration of spiked tumor cells was linear over the range of 5 to 1,142 cells, with an average recovery of >/=85% at each spike level. Only 1 of the 344 (0.3%) healthy and nonmalignant disease subjects had >/=2 CTCs per 7.5 mL of blood. In 2,183 blood samples from 964 metastatic carcinoma patients, CTCs ranged from 0 to 23,618 CTCs per 7.5 mL (mean, 60 +/- 693 CTCs per 7.5 mL), and 36% (781 of 2,183) of the specimens had >/=2 CTCs. Detection of >/=2 CTCs occurred at the following rates: 57% (107 of 188) of prostate cancers, 37% (489 of 1,316) of breast cancers, 37% (20 of 53) of ovarian cancers, 30% (99 of 333) of colorectal cancers, 20% (34 of 168) of lung cancers, and 26% (32 of 125) of other cancers.

CONCLUSIONS

The CellSearch system can be standardized across multiple laboratories and may be used to determine the clinical utility of CTCs. CTCs are extremely rare in healthy subjects and patients with nonmalignant diseases but present in various metastatic carcinomas with a wide range of frequencies.

Circulating tumor cells: a novel prognostic factor for newly diagnosed metastatic breast cancer

PURPOSE

Metastatic breast cancer (MBC) is incurable; its treatment is palliative. We investigated whether the presence of circulating tumor cells (CTCs) predicts treatment efficacy, progression-free survival (PFS), and overall survival (OS) in patients with newly diagnosed MBC who were about to start first-line therapy.

PATIENTS AND METHODS

One hundred seventy-seven patients with measurable MBC were enrolled onto a prospective study. Eighty-three of the 177 patients were entering first-line treatment, and these patients are the focus of this analysis. CTCs from 7.5 mL of whole blood drawn before treatment initiation (baseline) and monthly thereafter for up to 6 months were isolated and enumerated using immunomagnetics.

RESULTS

The mean (+/- standard deviation) follow-up time was 11.1 +/- 4.4 months (median, 12.2 months). Forty-three patients (52%) had > or = five CTCs at baseline. The median PFS was 7.2 months (95% CI, 4.9 to 9.4 months), and the median OS was more than 18 months. Patients with > or = five CTCs at baseline and at first follow-up (4 weeks) had a worse prognosis than patients with less than five CTCs (baseline: median PFS, 4.9 v 9.5 months, respectively; log-rank, P = .0014; median OS, 14.2 v > 18 months, respectively; log-rank, P = .0048; first follow-up: median PFS, 2.1 v 8.9 months, respectively; log-rank, P = .0070; median OS, 11.1 v > 18 months, respectively; log-rank, P = .0029). CTCs before and after the initiation of therapy were strong, independent prognostic factors.

CONCLUSION

Detection of CTCs before initiation of first-line therapy in patients with MBC is highly predictive of PFS and OS. This technology can aid in appropriate patient stratification and design of tailored treatments.