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Biomedical subjects

M Gion

Publications and source records attributed to M Gion.

At least 73 records · Page 4Linked to original sources
PubMedDate not supplied

Evaluation of HER-2/neu in serum and tissue of primary and metastatic breast cancer patients using an automated enzyme immunoassay.

Serum HER-2/neu concentrations were evaluated in 172 healthy subjects, 176 primary and 55 metastatic breast cancer patients, employing a new automated assay (Bayer Immuno 1 serum HER-2/neu). Using 13 ng/mL as the cutoff, abnormal HER-2/neu serum levels were found in 8% (14/176) of primary and 50.9% (28/55) of metastatic breast cancer patients. Both in primary and metastatic breast cancer a significant relationship was found with the stage of the disease when serum HER-2/neu was considered as a categorized variable (p=0.0003 and p=0.02, respectively), but not when it was taken as a continuous variable (p=0.247 and p=0.146, respectively). Moreover, we evaluated the correlation between Immuno 1 HER-2/neu and Oncogene Research Products ELISA assay in 53 normal subjects, 46 primary and 34 metastatic breast cancer patients. The correlation was relatively good (p<0.0001), although substantial differences could be found in single cases. The Immuno 1 assay was also evaluated for the first time in breast cancer tissue. The method, which showed good performance both in terms of imprecision and linearity, was used to measure HER-2/neu protein in 140 cytosol samples from primary breast cancer tissue and in homogenates from 40 matched cases. The correlation between the two matrixes was very close (p<0.0001). By contrast, no correlation was found between serum and matched cytosol (p=0.101) or homogenate samples (p=0.511).

Adult↗
PubMedDate not supplied

Quality control for biomarker determination in oncology: the experience of the Italian Network for Quality Assessment of Tumor Biomarkers (INQAT).

Biomarker analysis and evaluation in oncology is the product of a number of processes (including managerial, technical and interpretation steps) which need to be monitored and controlled to prevent and correct errors and guarantee a satisfactory level of quality. Several biomarkers have recently moved to clinical validation studies and successively to clinical practice without any definition of standard procedures and/or quality control (QC) schemes necessary to guarantee the reproducibility of the laboratory information. In Italy several national scientific societies and single researchers have activated -- often on a pilot level -- specific external quality assessment protocols, thereby potentially jeopardizing the clinical reality even further. In view of the seriousness of the problem, in 1998 the Italian Ministry of Health sponsored a National Survey Project to coordinate and standardize the procedures and to develop QC programs for the analysis of cancer biomarkers of potential clinical relevance. Twelve QC programs focused on biomarkers and concerning morphological, immunohistochemical, biochemical, molecular, and immunoenzymatic assays were coordinated and implemented. Specifically, external QC programs for the analytical phase of immunohistochemical p53, Bcl-2, c-erb-2/neu/HER2, and microvessel density determination, of morphological evaluation of tumor differentiation grade, and of molecular p53 analysis were activated for the first time within the project. Several hundreds of Italian laboratories took part in these QC programs, the results of which are available on the web site of the Network (www.cqlaboncologico.it). Financial support from the Italian Government and the National Research Council (CNR) will guarantee the pursuit of activities that will be extended to new biomarkers, to preanalytical phases of the assays, and to revision of the criteria of clinical usefulness for evaluating the cost/benefit ratio.

Autoradiography↗
PubMedDate not supplied

The prognostic value of vascular endothelial growth factor, urokinase plasminogen activator and plasminogen activator inhibitor-1 in node-negative breast cancer.

The vascular endothelial growth factor (VEGF) and the plasminogen activator system play an essential role in solid tumor angiogenesis and in tumor invasion and metastasis. In the present study we investigated the relationship between patient outcome and levels of VEGF, urokinase plasminogen activator (uPA) and plasminogen activator inhibitor-1 (PAI-1) in tumor cytosols of 196 node-negative primary invasive breast cancer patients who did not receive any adjuvant therapy. The median follow-up was 65 months. VEGF, uPA and PAI-1 were measured by commercially available enzyme-linked immunosorbent assays. Cox's univariate analysis showed that pT (p = 0.0007), uPA (p = 0.0156) and PAI-1 (p = 0.0015) had a significant impact on relapse-free survival, whereas VEGF did not have any prognostic value (p = 0.18). Bivariate analysis showed significant interactions between uPA and PAI-1 (p = 0.0035) and between VEGF and PAI-1 (p = 0.006). Our study confirms that uPA and PAI-1 cytosol levels can be considered as prognostic factors for relapse-free survival in node-negative breast cancer. Moreover, the interaction between VEGF and PAI-1 warrants further investigation into the relationship between the biomarkers of angiogenesis and those of the protease cascade.

Adult↗
PubMedDate not supplied

Free DNA in urine: a new marker for bladder cancer? Preliminary data.

The aim of the present preliminary study was to investigate the presence of free DNA (FDNA) in urine as a possible marker for the diagnosis of bladder cancer. Naturally voided morning urine specimens were collected from 57 patients with suspected bladder cancer before cystoscopy. A standard urine test was performed; the specimens were then processed in order to obtain a quantitative evaluation of the presence of free DNA in the urine. Twenty-two patients were excluded from the study because they had leukocyturia and/or bacteriuria. Free DNA concentrations higher than 250 ng/mL were found in all 16 patients showing bladder cancer at cystoscopy and in seven (36.8%) of the 19 patients with negative cystoscopy. Urinary FDNA seems to have an excellent sensitivity: we observed no false negative cases and 36.8% false positive cases. By contrast, only 6.25% of the bladder cancer patients had positive urine cytology. Our results seem promising, although further studies and larger numbers are needed to define urinary free DNA as a reliable marker of bladder cancer.

Aged↗
PubMedDate not supplied

Comparison between two methods in the determination of circulating chromogranin A in neuroendocrine tumors (NETs): results of a prospective multicenter observational study.

Several methods for analyzing CgA using either monoclonal or polyclonal antibodies have been developed, which differ in their diagnostic performance. The present paper describes the results of a prospective multicenter study aimed at comparing the clinical value of the two most widely used commercially available CgA assay kits in patients affected by neuroendocrine tumors (NETs). Two hundred sixty-one patients from 40 different centers and 99 healthy subjects were evaluated. CgA levels were measured with two different methods, a two-step immunoradiometric assay (IRMA) and an enzyme-linked immunosorbent assay (ELISA). CgA was measured centrally by two reference laboratories, one of which used IRMA and the other ELISA, and it was measured by the participating institutions with the method routinely used by each of them. The major findings of the present study were: (i) the two assays for the determination of CgA present good diagnostic performance; (ii) both assays are robust and guarantee comparable results when applied in different settings (central vs local laboratory); (iii) the negative/positive cutoff points (87 ng/mL for IRMA and 21.3 U/L for ELISA) were established according to standardized criteria; (iv) the results obtained with the two assays in basal clinical samples of patients affected by NETs show an apparently satisfactory correlation (rs = 0.843, p < 0.0001). However, a possibly clinically meaningful 36% discordance rate was found. These findings support the hypothesis that the two CgA kits might provide partially different information.

Adult↗
PubMedDate not supplied

Carcinoembryonic antigen, ferritin, tissue polypeptide antigen, and CA15/3 in breast cancer: relationship between carcinoma and normal breast tissue.

The study of tumor markers in breast cancer tissue may supply information on the tumor's biological features and its clinical behaviour. Forty-nine primary breast cancer patients are evaluable to date. CEA, ferritin, TPA and CA15/3 were measured with radioimmunometric methods in the cytosol of carcinoma and normal tissue from the same breast. The concentrations of the four markers were higher in the tumor than in normal tissue in 42/49 cases for CEA, 47/49 for ferritin, 42/49 for TPA and in 24/29 for CA15/3. However, an overlap was found between carcinoma and normal tissue levels, particularly for CEA and TPA. We can conclude that the four substances studied may be markers of malignancy in breast carcinoma when non-malignant breast tissue from the same patient is determined at the same time, whereas assays within a single, unknown breast tissue sample may be useful only in the case of ferritin and, partly, CA15/3.

Antigens, Neoplasm↗
PubMedDate not supplied

Evaluation of a radioreceptor assay to assess exogenous estrogen activity in serum of patients with breast cancer.

A radioreceptor assay (RRA) for the determination of total estrogen activity, was set up and used to assess the possible presence of exogenous molecules with estrogen activity in serum; a comparison was made with the specific radioimmunoassay (RIA) for the endogenous estrogen 17-B estradiol (17-B-E2). The assay was first performed on sera from healthy people taking estrogens in the form of oral contraceptives or lotions for local application whose total estrogenic activity in the blood was assumed to be abnormal. The assay was then performed on serum from 98 patients with early breast cancer and 20 patients with metastasis, not undergoing hormone therapy. A higher estrogen activity was found in 2.5% of sera compared to the activity found using the RIA method which is specific for endogenous estrogen 17-B-E2, the RRA/17-B-E2 ratio being higher than 3. Increased estrogen activity was found in 10% serum samples from digoxin treated cardiopathic patients, with an RRA/17-B-E2 ratio ranging from 4.4 to 20. The RRA assay could prove useful for showing up exogenous estrogen activity from various sources (drugs, food) in sera of people in whom estrogen stimulation could be potentially dangerous (i.e. in patients with hormone-sensitive tumors). This exogenous activity could support a certain degree of neoplastic stimulation and, therefore, unfavourably condition the patients' therapeutic response.

Biomarkers, Tumor↗
PubMedDate not supplied

TAF test in primary esophageal carcinoma: comparison with other tumor markers.

An ELISA method for the determination of circulating specific HSV-TAA antibodies has recently become available (TAF test). The presence of TAF was tested in serum of 154 patients with primary esophageal carcinoma, collected in three institutions. The overall TAF-test positivity rate was 57.1%, being significantly lower in stage IV than in stage III patients. The concordance rate between TAF and CEA, ferritin, TPA, SCC and TATI was low, suggesting that TAF is probably independent of the other tumor markers evaluated. The clinical role of TAF-test determination in patients with esophageal carcinoma is currently under evaluation.

Aged↗
PubMedDate not supplied

Cost/effectiveness ratio of carcinoembryonic antigen--importance of adequacy of routine requests of tumor markers.

Since 1987 we have been evaluating the cost/effectiveness ratio of tumor markers using carcinoembryonic antigen (CEA) as a leading indicator. Preliminary to the evaluation of cost/effectiveness ratio we verified the fitness of CEA requests to the proper clinical problems in order to identify any bias of cost due to inadequate CEA use. 2677 CEA orders were evaluated in 1987. The percentage of inadequate requests was very high (43%). Therefore, it seemed not advisable to carry out the evaluation of cost/effectiveness ratio, while educational actions (divulgation of informative material, service of telephone consultation) were addressed to the physicians of the geographic area of laboratory users. In 1991 the adequacy of CEA requests was reevaluated. The percentage of inadequate requests on 2647 orders was 29.4%. This result, although not yet satisfactory, suggests that proper educational programs may probably improve the fitness of tumor marker requests to correct clinical problems. Additional educational actions are mandatory to further reduce the rate of inadequate tumor marker orders.

Carcinoembryonic Antigen↗
PubMedDate not supplied

A new approach to tumour marker assessment by perioperative determination in breast and colorectal cancer.

Preoperative serum tumour markers are currently classified as positive or negative according to a predetermined cut-off point. In the present study we examined the dynamic variation of marker levels after radical surgery of breast and colorectal cancer. CEA and CA15.3 were measured in 93 patients with breast cancer, CEA and CA19.9 in 97 patients with colorectal carcinoma before and 30 days after radical surgery. Any variation higher than 3-fold the analytical coefficient of variation of the assay was considered significant. In patients with negative preoperative marker levels a significant decrease was noted after surgery in 15.6% of cases for CEA and 27.8% for CA15.3 in breast cancer and in 46.8% for CEA and 25.7% for CA19.9 in colorectal cancer. Using both cut-off-based and dynamic criteria, we found an overall positivity rate of 19.6% for CEA and 33.3% for CA15.3 in breast cancer; 60.0% for CEA and 37.1% for CA19.9 in colorectal cancer. From the present findings we conclude that the dynamic study of perioperative variations of tumour markers is a sensitive method additional to cut-off-based criteria for the assessment of the phenotypic expression of the marker by the tumour.

Antigens, Tumor-Associated, Carbohydrate↗
PubMedDate not supplied

Relationship between cytosol TPS, TPA and cell proliferation.

The serological tumor marker tissue polypeptide antigen (TPA) and the more recently identified tissue-specific polypeptide antigen (TPS) have been reported to be indicators of the proliferation rate of the tumor. In the present investigation we compared the cytosol level of the two markers with the proliferative activity of the tumor measured using the 3H-thymidine labelling index. The preliminary results presented here show that higher TLI is associated with lower cytosol levels of both TPA and TPS. TPA and TPS in the cytosol were significantly associated. These findings are in agreement with the previously demonstrated association between high TPA cytosol levels and better prognosis in breast cancer. Further studies are ongoing in order to: 1. confirm these findings in a larger patient series; 2. investigate any possible prognostic indication provided by TPS; 3. evaluate any possible biological meaning of the negative association between TPA/TPS and TLI in the cytosol of breast cancer.

Biomarkers, Tumor↗
PubMedDate not supplied

Evaluation of critical differences of CEA and CA 15.3 levels in serial samples from patients operated for breast cancer.

In the present investigation we evaluated the variability of tumor marker levels in the follow-up of patients without evidence of disease after resection of primary breast cancer. CEA and CA15.3 were measured using commercially available methods in serial blood samples collected from 170 patients. The coefficient of variation among all samples from each patient, which accounts for the total variability (analytical variability+biological variability), was widely scattered (from 4 to 99% for CEA; from 4 to 52% for CA15.3). The critical difference was calculated using the formula designed by Fraser [CD = 2.77. (CVa2 + CVb2)1/2]. It ranged from 11 to 276 for CEA and from 11 to 144 for CA15.3. From the present findings we conclude that: 1) it is possible to identify individually tailored decision criteria to evaluate tumor marker variations in the follow-up of breast cancer patients; 2) in a considerable number of cases the non-tumor-related variability is too high to allow the early identification of minor tumor marker variations that are of clinical relevance.

Analysis of Variance↗