Neural network-derived multivariate index assay demonstrates effective clinical performance in longitudinal monitoring of ovarian cancer risk.

OBJECTIVE: We recently characterized the clinical performance of a multivariate index assay (MIA3G) to assess ovarian cancer risk for adnexal masses at initial presentation. This study evaluated how MIA3G varies when applied longitudinally to monitor risk during clinical follow-up. METHOD: The study evaluated women presenting with adnexal masses from eleven centers across the US. Patients received an initial blood draw at enrollment and at the standard-of-care follow-up visits. MIA3G was determined for all visits but physicians did not have access to MIA3G scores to determine clinical management. The primary outcome was the relative change value (RCV) of MIA3G over the period of clinical observation. RESULTS: A total of 510 patients of 785 enrolled met study criteria. Of these, 30.8% had a second, 25.4% a third and 22.2% a fourth blood draw following initial collection. The median duration from initial draw was 131 d to second draw, 301.5 d to the third draw and 365.5 d to the fourth draw. MIA3G RCV of >50% was observed in 22-26% patients, whereas 70-75% patients had MIA3G RCV >5%. An empirical baseline RCV of 56% - transformed to 1 in logarithmic scale - was calculated from averaging RCVs of all patients who had no malignancy risk after 210 days. RCV > 1 log was associated with higher incidence of surgical intervention (29.6%) compared to RCV < 1 log (16.9%). CONCLUSIONS: Variation in MI3AG does not change the accuracy of the test for excluding malignancy, while marked changes may be associated with a slightly higher likelihood of surgical intervention. In addition to MIA3G score itself, the MIA3G RCV may be important for clinical management.

Ethnic disparity in clinical performance between multivariate index assay and CA125 in detection of ovarian malignancy.

Aim: Based on evidence that African-American (AA) women have lower CA125 values than Caucasian (C) women, we investigated this to see if this disparity would have an impact on ovarian cancer detection using CA125 and multivariate index assay (MIA). Materials & methods: Serum from two prospective trials of 1029 (274 malignancies [250 C/24AA]) were analyzed for CA125 and MIA results. Clinical performance was calculated. Results: Sensitivity of MIA in Caucasian women was 93.2%, 74.4% for CA125 at the ACOG approved cut-off level of 200 U/ml cutoff, and 80.4% using the 2007, Dearking 67 U/ml cutoff. In AA American women, MIA sensitivity was 79.2%, 33.3% for CA125 at the ACOG approved cut-off levels and 62.5% at the 2007, Dearking 67 U/ml cutoff. Conclusion: Our results support that CA125 in AA women with adnexal masses has lower sensitivity than MIA no matter what the cutoff value is. Implementation of MIA in evaluation of adnexal masses should increase sensitivity of detection of malignancy compared with CA125, particularly in AA women.

Adnexal mass risk assessment: a multivariate index assay for malignancy risk stratification.

Aims: Adnexal mass risk assessment (AMRA) stratifies patients with adnexal masses, identifying the relatively small number of malignancies from benigns which might take a 'watchful waiting' approach. Methods: AMRA uses seven biomarkers and derived from women with adnexal masses scheduled for surgery. Estimated clinical performance was calculated using fixed prevalence. Results: At 5% prevalence, the high-risk group, 7.9% total, captured 75.9% of invasive malignancies at a positive predictive value of 35.8%. High risk/intermediate risk combined had a sensitivity of 89.7 and 95.6% for pre- and post-menopausal cancers, respectively. The low-risk group, 67.8% total, had an negative predictive value of 99.0%. Conclusion: With highly differentiating risk stratification capability across histological subtypes and stages, AMRA is potentially applicable to patients with adnexal masses to assist deciding whether immediate surgery is recommended.

CA11-19: a tumor marker for the detection of colorectal cancer.

BACKGROUND AND AIM: Colorectal cancer (CRC) remains the second most frequent cause of cancer deaths in the United States. Blood tests using tumor-related antigens aid in diagnosing CRC. However, higher sensitivity and specificity are needed before an acceptable tumor antigen blood test for CRC is clinically useful. This study describes the diagnostic accuracy of an enzyme-linked immunosorbent assay for the CA11-19 serologic tumor antigen for the detection of CRC. METHODS: Serum specimens were obtained from 522 colonoscopy-confirmed subjects in institutional review board-approved studies. Specimens were blind coded. CA11-19 levels were determined by using enzyme-linked immunosorbent assay analysis. The results were tabulated for categories of normal, hyperplastic polyps, benign GI, adenomatous polyps, and CRC based on their final diagnosis. RESULTS: When a cutoff of 6.4 units/mL for normal is used, the CA11-19 level was elevated in 128 of 131 of CRC subjects, for an observed sensitivity of 98% (95% confidence interval, 93.1%-99.5%). Normal levels were found in 87% of normal subjects (90/103) and 83% of those with benign GI diseases (185/223). When combined, this yields an observed specificity of 84% (95% confidence interval, 80.0%-87.9%). CONCLUSION: CA11-19 is a serologic tumor marker for the diagnosis of CRC with a sensitivity of 98% and specificity of 84%. This high sensitivity means that this test will detect 43 of 44 cases of CRC presented. For those older than 50 years of age, it has a positive predictive value of 3.6% and a negative predictive value of 99.98%. Additional prospective studies are needed to further clarify the use of CA11-19 as an aid in the diagnosis of CRC.

Ovarian Cancer surgical consideration is markedly improved by the neural network powered-MIA3G multivariate index assay.

Background: Surgery remains the main treatment option for an adnexal mass suspicious of ovarian cancer. The malignancy rate is, however, only 10-15% in women undergoing surgery. This results in a high number of unnecessary surgeries. A surveillance-based approach is recommended to form the basis for surgical referrals. We have previously reported the clinical performance of MIA3G, a deep neural network-based algorithm, for assessing ovarian cancer risk. In this study, we show that MIA3G markedly improves the surgical selection for women presenting with adnexal masses. Methods: MIA3G employs seven serum biomarkers, patient age, and menopausal status. Serum samples were collected from 785 women (IQR: 39-55 years) across 12 centers that presented with adnexal masses. MIA3G risk scores were calculated for all subjects in this cohort. Physicians had no access to the MIA3G risk score when deciding upon a surgical referral. The performance of MIA3G for surgery referral was compared to clinical and surgical outcomes. MIA3G was also tested in an independent cohort comprising 29 women across 14 study sites, in which the physicians had access to and utilized MIA3G prior to surgical consideration. Results: When compared to the actual number of surgeries (n = 207), referrals based on the MIA3G score would have reduced surgeries by 62% (n = 79). The reduction was higher in premenopausal patients (77%) and in patients ≤55 years old (70%). In addition, a 431% improvement in malignancy prediction would have been observed if physicians had utilized MIA3G scores for surgery selection. The accuracy of MIA3G referral was 90.00% (CI 87.89-92.11), while only 9.18% accuracy was observed when the MIA3G score was not used. These results were corroborated in an independent multi-site study of 29 patients in which the physicians utilized MIA3G in surgical consideration. The surgery reduction was 87% in this cohort. Moreover, the accuracy and concordance of MIA3G in this independent cohort were each 96.55%. Conclusion: These findings demonstrate that MIA3G markedly augments the physician's decisions for surgical intervention and improves malignancy prediction in women presenting with adnexal masses. MIA3G utilization as a clinical diagnostic tool might help reduce unnecessary surgeries.

A 2-stage ovarian cancer screening strategy using the Risk of Ovarian Cancer Algorithm (ROCA) identifies early-stage incident cancers and demonstrates high positive predictive value.

BACKGROUND: A 2-stage ovarian cancer screening strategy was evaluated that incorporates change of carbohydrate antigen 125 (CA125) levels over time and age to estimate risk of ovarian cancer. Women with high-risk scores were referred for transvaginal ultrasound (TVS). METHODS: A single-arm, prospective study of postmenopausal women was conducted. Participants underwent an annual CA125 blood test. Based on the Risk of Ovarian Cancer Algorithm (ROCA) result, women were triaged to next annual CA125 test (low risk), repeat CA125 test in 3 months (intermediate risk), or TVS and referral to a gynecologic oncologist (high risk). RESULTS: A total of 4051 women participated over 11 years. The average annual rate of referral to a CA125 test in 3 months was 5.8%, and the average annual referral rate to TVS and review by a gynecologic oncologist was 0.9%. Ten women underwent surgery on the basis of TVS, with 4 invasive ovarian cancers (1 with stage IA disease, 2 with stage IC disease, and 1 with stage IIB disease), 2 ovarian tumors of low malignant potential (both stage IA), 1 endometrial cancer (stage I), and 3 benign ovarian tumors, providing a positive predictive value of 40% (95% confidence interval = 12.2%, 73.8%) for detecting invasive ovarian cancer. The specificity was 99.9% (95% confidence interval = 99.7%, 100%). All 4 women with invasive ovarian cancer were enrolled in the study for at least 3 years with low-risk annual CA125 test values prior to rising CA125 levels. CONCLUSIONS: ROCA followed by TVS demonstrated excellent specificity and positive predictive value in a population of US women at average risk for ovarian cancer.

A reflex testing protocol using two multivariate index assays improves the risk assessment for ovarian cancer in patients with an adnexal mass.

OBJECTIVES: Patients with adnexal masses suspicious for malignancy benefit from referral to oncology specialists during presurgical assessment of the mass. OVA1 is a multivariate assay using a five-biomarker panel which offers high overall and early-stage sensitivity. However, OVA1 has a high false-positive rate for benign masses. Overa, a second-generation multivariate index assay was developed to reduce the false-positive rate. The aim of the present study was to use Overa as a reflex for OVA1 and increase specificity. METHODS: OVA1 cut-off scores were established to place patients into three categories: low, intermediate, and high cancer risk. Samples with intermediate-risk OVA1 scores were reflexed to the Overa and defined as high or low risk. This protocol was tested with 1035 prospectively collected serum samples and validated with an independent prospectively collected sample set (N = 207). RESULTS: Thirty-five per cent (359) of samples had intermediate OVA1 scores. Reflexing these to Overa eliminated 58% of the false-positives and improved the overall specificity from 50% to 72%. This finding was confirmed in the independent dataset, in which the specificity increased from 56% to 73%. CONCLUSIONS: Reflexing samples with intermediate OVA1 scores significantly decreases the false-positive rate, thereby reducing unnecessary surgical referrals.

Validation of a deep neural network-based algorithm supporting clinical management of adnexal mass.

Background: Conservative management of adnexal mass is warranted when there is imaging-based and clinical evidence of benign characteristics. Malignancy risk is, however, a concern due to the mortality rate of ovarian cancer. Malignancy occurs in 10-15% of adnexal masses that go to surgery, whereas the rate of malignancy is much lower in masses clinically characterized as benign or indeterminate. Additional diagnostic tests could assist conservative management of these patients. Here we report the clinical validation of OvaWatch, a multivariate index assay, with real-world evidence of performance that supports conservative management of adnexal masses. Methods: OvaWatch utilizes a previously characterized neural network-based algorithm combining serum biomarkers and clinical covariates and was used to examine malignancy risk in prospective and retrospective samples of patients with an adnexal mass. Retrospective data sets were assembled from previous studies using patients who had adnexal mass and were scheduled for surgery. The prospective study was a multi-center trial of women with adnexal mass as identified on clinical examination and indeterminate or asymptomatic by imaging. The performance to detect ovarian malignancy was evaluated at a previously validated score threshold. Results: In retrospective, low prevalence (N = 1,453, 1.5% malignancy rate) data from patients that received an independent physician assessment of benign, OvaWatch has a sensitivity of 81.8% [95% confidence interval (CI) 65.1-92.7] for identifying a histologically confirmed malignancy, and a negative predictive value (NPV) of 99.7%. OvaWatch identified 18/22 malignancies missed by physician assessment. A prospective data set had 501 patients where 106 patients with adnexal mass went for surgery. The prevalence was 2% (10 malignancies). The sensitivity of OvaWatch for malignancy was 40% (95% CI: 16.8-68.7%), and the specificity was 87% (95% CI: 83.7-89.7) when patients were included in the analysis who did not go to surgery and were evaluated as benign. The NPV remained 98.6% (95% CI: 97.0-99.4%). An independent analysis set with a high prevalence (45.8%) the NPV value was 87.8% (95% CI: 95% CI: 75.8-94.3%). Conclusion: OvaWatch demonstrated high NPV across diverse data sets and promises utility as an effective diagnostic test supporting management of suspected benign or indeterminate mass to safely decrease or delay unnecessary surgeries.

Analytical Validation of a Deep Neural Network Algorithm for the Detection of Ovarian Cancer.

PURPOSE: Early detection of ovarian cancer, the deadliest gynecologic cancer, is crucial for reducing mortality. Current noninvasive risk assessment measures include protein biomarkers in combination with other clinical factors, which vary in their accuracy. Machine learning can be applied to optimizing the combination of these features, leading to more accurate assessment of malignancy. However, the low prevalence of the disease can make rigorous validation of these tests challenging and can result in unbalanced performance. METHODS: MIA3G is a deep feedforward neural network for ovarian cancer risk assessment, using seven protein biomarkers along with age and menopausal status as input features. The algorithm was developed on a heterogenous data set of 1,067 serum specimens from women with adnexal masses (prevalence = 31.8%). It was subsequently validated on a cohort almost twice that size (N = 2,000). RESULTS: In the analytical validation data set (prevalence = 4.9%), MIA3G demonstrated a sensitivity of 89.8% and a specificity of 84.02%. The positive predictive value was 22.45%, and the negative predictive value was 99.38%. When stratified by cancer type and stage, MIA3G achieved sensitivities of 94.94% for epithelial ovarian cancer, 76.92% for early-stage cancer, and 98.04% for late-stage cancer. CONCLUSION: The balanced performance of MIA3G leads to a high sensitivity and high specificity, a combination that may be clinically useful for providers in evaluating the appropriate management strategy for their patients. Limitations of this work include the largely retrospective nature of the data set and the unequal, albeit random, assignment of histologic subtypes between the training and validation data sets. Future directions may include the addition of new biomarkers or other modalities to strengthen the performance of the algorithm.

National Academy of Clinical Biochemistry Laboratory Medicine Practice Guidelines for use of tumor markers in liver, bladder, cervical, and gastric cancers.

BACKGROUND: Updated National Academy of Clinical Biochemistry Laboratory Medicine Practice Guidelines for the use of tumor markers in the clinic have been developed. METHODS: Published reports relevant to use of tumor markers for 4 cancer sites--liver, bladder, cervical, and gastric--were critically reviewed. RESULTS: Alpha-fetoprotein (AFP) may be used in conjunction with abdominal ultrasound for early detection of hepatocellular carcinoma (HCC) in patients with chronic hepatitis or cirrhosis associated with hepatitis B or C virus infection. AFP concentrations >200 microg/L in cirrhotic patients with typical hypervascular lesions >2 cm in size are consistent with HCC. After a diagnosis of HCC, posttreatment monitoring with AFP is recommended as an adjunct to imaging, especially in the absence of measurable disease. Although several urine markers have been proposed for bladder cancer, none at present can replace routine cystoscopy and cytology in the management of patients with this malignancy. Some may, however, be used as complementary adjuncts to direct more effective use of clinical procedures. Although carcinoembryonic antigen and CA 19-9 have been proposed for use gastric cancer and squamous cell carcinoma antigen for use in cervical cancer, none of these markers can currently be recommended for routine clinical use. CONCLUSIONS: Implementation of these recommendations should encourage optimal use of tumor markers for patients with liver, bladder, cervical, or gastric cancers.

Survey of canine use and safety of isoxazoline parasiticides.

A veterinarian and pet owner survey (Project Jake) examined the use and safety of isoxazoline parasiticides given to dogs. Data were received during August 1-31, 2018 from a total of 2,751 survey responses. Forty-two percent (1,157) reported no flea treatment or adverse events (AE), while 58% (1594) had been treated with some parasiticide for flea control, and of those that received a parasiticide, the majority, or 83% (1,325), received an isooxazoline. When any flea treatment was given, AE were reported for 66.6% of respondents, with no apparent AE noted for 36.1%. Project Jake findings were compared to a retrospective analysis of publicly available Food and Drug Administration (FDA) and European Medicines Agency (EMA) reported AE. The number of total AE reported to FDA and EMA were comparable, although a 7 to 10 times higher occurrence of death and seizures was reported from the EMA or from outside the United States (US). Serious AE responses for death, seizures and neurological effects reported in our survey were higher than the FDA but moderately lower than the EMA reports. These sizable global data sets combined with this pre- and post-parasiticide administration survey indicated that isoxazoline neurotoxicity was not flea- and tick-specific. Post-marketing serious AE were much higher than in Investigational New Drug (IND) submissions. Although the labels have recently been updated, dogs, cats and their caregivers remain impacted by their use. These aggregate data reports support the need for continued cross-species studies and critical review of product labelling by regulatory agencies and manufacturers.

Multivariate Index Assay Is Superior to CA125 and HE4 Testing in Detection of Ovarian Malignancy in African-American Women.

OBJECTIVE: To review and analyze the serum values of risk of ovarian malignancy algorithm (ROMA) and multivariate index assay (MIA) in subgroups of women who underwent surgery for adnexal masses to determine sensitivity, specificity, and positive and negative predictive values for the detection of malignancy in different ethnic populations. METHODS: Serum samples from 2 prospective trials of 1029 women in which 274 women diagnosed with malignancy were analyzed for ROMA scores and MIA results. Biomarker data were obtained from the previous prospective studies that validated the MIA test. Of these, 250 women were Caucasian (C) and 24 were African-American (AA). Sensitivity, specificity, positive and negative predictive values, and confidence intervals for preoperative test results were calculated using DTComPair package of the R programming language. In premenopausal women, a ROMA value equal to or greater than 1.14 indicates a high risk of finding epithelial ovarian cancer. In premenopausal women, MIA values greater than 5.0 are associated with a greater risk of malignancy. In postmenopausal women, a ROMA value equal to or greater than 2.99 indicates a high risk of finding epithelial ovarian cancer. In postmenopausal women, MIA values greater than 4.4 are associated with a greater risk of malignancy. RESULTS: Primary ovarian malignancy was diagnosed in 179 cases (167 C/12 AA) and metastatic disease to the ovary in an additional 27 cases (22 C/5 AA). Overall results are shown below. CONCLUSIONS: Our results demonstrate that ROMA in AA women with adnexal masses have lower sensitivity for the detection of malignancy than does MIA. Implementation of MIA in the evaluation of adnexal masses will increase the sensitivity of the detection of malignancy compared with ROMA, with the most marked results in AA women.

Validation of reverse phase protein array for practical screening of potential biomarkers in serum and plasma: accurate detection of CA19-9 levels in pancreatic cancer.

The current study analyzed reverse phase protein arrays (RPPA) as a means to experimentally validate biomarkers in blood samples. One microliter samples of sera (n = 71), and plasma (n = 78) were serially diluted and printed on NC-coated slides. CA19-9 levels from RPPA results were compared with identical patient samples as measured by ELISA. There was a strong correlation between RPPA and ELISA (r = 0.87) as determined by scatter plots. Sample reproducibility of CA19-9 levels was excellent (interslide correlation r = 0.88; intraslide correlation r = 0.83). The ability of RPPA to accurately distinguish CA19-9 levels between cancer and noncancer samples were determined using receiver operating characteristic curves and compared with ELISA. The AUC for RPPA and ELISA was comparable (0.87 and 0.86, respectively). When the mean CA19-9 levels of normal samples was used as a cutoff for RPPA and compared with the standard clinical ELISA cutoff, comparable specificities (71% for both) were observed. Notably, RPPA samples normalized to albumin showed increased sensitivity compared to ELISA (90% vs. 75%). As RPPA is a high-throughput method that shows results comparable to that of ELISA, we propose that RPPA is a viable technique for rapid experimental screening and validation of candidate biomarkers in blood samples.

PCA3 molecular urine assay correlates with prostate cancer tumor volume: implication in selecting candidates for active surveillance.

PURPOSE: Prostate cancer gene 3 (PCA3) has shown promise as a molecular marker in prostate cancer detection. We assessed the association of urinary PCA3 score with prostatectomy tumor volume and other clinical and pathological features. MATERIALS AND METHODS: Urine specimens were collected after digital rectal examination from 59 men scheduled for prostate biopsy and 83 men scheduled for radical prostatectomy. Prostatectomy findings were evaluable for 96 men. PCA3 and prostate specific antigen mRNAs were quantified with Gen-Probe DTS 400 System. The PCA3 score was defined as the ratio of PCA3 mRNA/prostate specific antigen mRNA x10(3). RESULTS: The PCA3 score in men with negative biopsies (30) and positive biopsies (29) were significantly different (median 21.1 and 31.0, respectively, p = 0.029). The PCA3 score was significantly correlated with total tumor volume in prostatectomy specimens (r = 0.269, p = 0.008), and was also associated with prostatectomy Gleason score (6 vs 7 or greater, p = 0.005) but not with other clinical and pathological features. The PCA3 score was significantly different when comparing low volume/low grade cancer (dominant tumor volume less than 0.5 cc, Gleason score 6) and significant cancer (p = 0.007). On multivariate analysis PCA3 was the best predictor of total tumor volume in prostatectomy (p = 0.001). Receiver operating characteristic curve analysis showed that the PCA3 score could discriminate low volume cancer (total tumor volume less than 0.5 cc) well with area under the curve of 0.757. CONCLUSIONS: The PCA3 score appears to stratify men based on prostatectomy tumor volume and Gleason score, and may have clinical applicability in selecting men who have low volume/low grade cancer.

Circulating tumor cells in peripheral blood samples from patients with increased serum prostate specific antigen: initial results in early prostate cancer.

PURPOSE: We evaluated the hypothesis that circulating tumor cells as determined using the CellSearch System would correlate with tumor volume, pathological stage and Gleason score in men with localized prostate cancer. MATERIALS AND METHODS: Samples of blood (30 ml) were drawn from 97 men with localized prostate cancer before radical prostatectomy, on postoperative days 2 to 3 and at 6 weeks. A control group consisted of 25 men with an increased prostate specific antigen and no tumor detected on extended prostate biopsy. Samples were analyzed for circulating tumor cells using the CellSearch System. RESULTS: Circulating tumor cells were detected in 21% of patients with cancer and 20% of controls (p = 0.946). At 6 weeks after prostatectomy circulating tumor cells were detected in 16% and 11% (p = 0.51) of the men positive and negative for circulating tumor cells at baseline, respectively. Of the 20 patients with cancer who had circulating tumor cells at baseline 18 showed no circulating tumor cells after surgery. Circulating tumor cell values did not correlate with tumor volume, pathological stage or Gleason score. Only 3.1% of the men with cancer and 8% of the control group had 3 or more circulating tumor cells per 22.5 ml blood at baseline. CONCLUSIONS: In metastatic breast, prostate and other cancers more than 5 circulating tumor cells are often detected using the CellSearch System, and may correlate with prognosis. However, in the setting of localized prostate cancer the number of detectable circulating tumor cells was low, with findings comparable to those in men who were biopsy negative for cancer. We found no correlation between the number of circulating tumor cells and known prognostic factors in this population.

A multicenter evaluation of the Iris iQ200 automated urine microscopy analyzer body fluids module and comparison with hemacytometer cell counts.

Manual hemacytometer cell counting of body fluids is labor-intensive and requires skilled testing personnel. We performed a multicenter evaluation of the Iris iQ200 automated microscopy analyzer Body Fluids Module (Iris Diagnostics, Chatsworth, CA) and compared 350 iQ200 body fluid cell counts with manual hemacytometer cell counts. Within-run imprecision, expressed as coefficient of variation (CV), ranged from 2.6% to 5.9% for RBC counts between 875 and 475 x 10(6)/L and from 4.2% to 6.5% for nucleated cell counts between 820 and 590 x 10(6)/L. The lower limits of detection, based on a CV of 20% or less, were 30 and 35 x 10(6)/L for RBCs and nucleated cells, respectively. There was very good agreement between automated iQ200 and manual body fluid cell counts based on slopes and r2 values. The iQ200 has satisfactory performance for enumerating RBCs and nucleated cells in most body fluids, with the exception of cerebrospinal fluid specimens that contain low cell numbers.

Detection of circulating tumor cells in peripheral blood of patients with metastatic breast cancer: a validation study of the CellSearch system.

PURPOSE: The CellSearch system (Veridex, Warren, NJ) is designed to enrich and enumerate circulating tumor cells (CTCs) from peripheral blood. Here, we validated the analytic performance of this system for clinical use in patients with metastatic breast cancer. EXPERIMENTAL DESIGN: This prospective multicenter study conducted at three independent laboratories involved samples from 92 patients with metastatic breast cancer. Intra- and inter-assay variability using controls containing defined numbers of cells (average, 50 and 1,000, respectively), cell stability based on varying storage and shipment conditions, recovery precision from samples spiked with 4 to 12 tumor cells, inter-instrument variability, and positivity of samples from metastatic breast cancer patients were tested. RESULTS: Intra- and inter-assay precision for two sites were high: All eight positive controls analyzed in the same run and >95% of the run to run control values (n=299) were within the specified ranges. Recovery rate of spiked samples averaged between 80% and 82%. CTCs were detected in approximately 70% of metastatic breast cancer patients. CTC values of identical samples processed either immediately after blood drawing or after storage for 24, 48, or 72 h at room temperature or at 4 degrees C did not differ significantly. Shipment of samples had no influence on CTC values. When analyzing identical samples in different centers, inter-instrument accordance was high. CONCLUSIONS: The CellSearch system enables the reliable detection of CTCs in blood and is suitable for the routine assessment of metastatic breast cancer patients in the clinical laboratory. Blood samples should be shipped at room temperature and CTC counts are stable for at least 72 h.

Application of Bayesian modeling of autologous antibody responses against ovarian tumor-associated antigens to cancer detection.

Biomarkers for early detection of epithelial ovarian cancer (EOC) are urgently needed. Patients can generate antibodies to tumor-associated antigens (TAAs). We tested multiplex detection of antibodies to candidate ovarian TAAs and statistical modeling for discrimination of sera of EOC patients and controls. Binding of serum antibody of women with EOC or healthy controls to candidate TAA-coated microspheres was assayed in parallel. A Bayesian model/variable selection approach using Markov Chain Monte Carlo computations was applied to these data, and serum CA125 values, to determine the best predictive model. The selected model was subjected to area under the receiver-operator curve (AUC) analysis. The best model generated an AUC of 0.86 [95% confidence interval (95% CI), 0.78-0.90] for discrimination between sera of EOC patients and healthy patients using antibody specific to p53, NY-CO-8, and HOXB7. Inclusion of CA125 in the model provided an AUC of 0.89 (95% CI, 0.84-0.92) compared with an AUC of 0.83 (95% CI, 0.81-0.85) using CA125 alone. However, using TAA responses alone, the model discriminated between independent sera of women with nonmalignant gynecologic conditions and those with advanced-stage or early-stage EOC with AUCs of 0.71 (95% CI, 0.67-0.76) and 0.70 (95% CI, 0.48-0.75), respectively. Serum antibody to p53 and HOXB7 is positively associated with EOC, whereas NY-CO-8-specific antibody shows negative association. Bayesian modeling of these TAA-specific serum antibody responses exhibits similar discrimination of patients with early-stage and advanced-stage EOC from women with nonmalignant gynecologic conditions and may be complementary to CA125.

Circulating tumor cells in metastatic breast cancer: biologic staging beyond tumor burden.

BACKGROUND: The detection of circulating tumor cells (CTCs) predicts overall survival in patients with metastatic breast cancer (MBC). However, it is unknown whether CTCs have superior value compared with other standard prognostic factors. We compared the prognostic significance of CTCs with clinical and laboratory measures of tumor burden and phenotypic subtype of disease. PATIENTS AND METHODS: One hundred fifty-one patients with MBC evaluated between 2000 and 2006 were included in this retrospective analysis. Circulating tumor cells were isolated and enumerated in whole blood using an immunomagnetic bead system (CellSearch System). Overall survival was evaluated according to the level of CTCs (negative: <5 CTCs per 7.5 mL of blood; positive: >or=5 CTCs per 7.5 mL of blood), Swenerton score, cancer antigen 27-29 level, age (<50 years vs. >or=50 years), hormone-receptor status and HER2 status, metastatic site, and type and line of therapy. RESULTS: The median age of patients was 53 years (range, 24-88 years), and 44% of the patients had >5 CTCs. The median overall survival for negative versus positive CTCs were 29.3 months and 13.5 months, respectively (P<0.0001). In the multivariable Cox model, the detection of>or=5 CTCs demonstrated the highest hazard ratio with 2.2 times the risk of death (P=0.003). The prognostic value was independent of measure of tumor burden and type and line of therapy, and phenotypic subtype of the disease. CONCLUSION: Circulating tumor cells have superior and independent prognostic value of tumor burden and disease phenotype and might represent an important marker of tumor biology in MBC. Detection of CTCs should be considered for new staging stratification of patients with MBC.