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Ana Herrero

Publications and source records attributed to Ana Herrero.

7 recordsLinked to original sources
PubMed2005

Robust and non-parametric statistics in the evaluation of figures of merit of analytical methods. Practices for students.

A set of laboratory practices is proposed in which evaluation of the quality of the analytical measurements is incorporated explicitly by applying systematically suitable methodology for extracting the useful information contained in chemical data. Non-parametric and robust techniques useful for detecting outliers have been used to evaluate different figures of merit in the validation and optimization of analytical methods. In particular, they are used for determination of the capability of detection according to ISO 11843 and IUPAC and for determination of linear range, for assessment of the response surface fitted using an experimental design to optimize an instrumental technique, and for analysis of a proficiency test carried out by different groups of students. The tools used are robust regression, least median of squares (LMS) regression, and some robust estimators as median absolute deviation (m.a.d.) or Huber estimator, which are very useful as an alternatives to the usual centralization and dispersion estimators.

Journal Article↗
PubMed2004

Phase II study of temozolomide and cisplatin as primary treatment prior to radiotherapy in newly diagnosed glioblastoma multiforme patients with measurable disease. A study of the Spanish Medical Neuro-Oncology Group (GENOM).

UNLABELLED: This phase II study evaluates the activity of temozolomide and cisplatin administered before radiation therapy in newly diagnosed glioblastoma multiforme patients, in terms of response, time to progression and survival. PATIENTS AND METHODS: Forty patients with measurable disease after surgery, a Karnofsky status > 60, and Barthel Index > 10 were included. They were treated with three cycles of temozolomide 200 mg/m2/day for 5 days and cisplatin 100 mg/m2 on day 1. Conventional focal radiation therapy to 60 Gy was administered after response evaluation. RESULTS: Three patients were not evaluable for central reviewed response but all 40 were evaluable for toxicity, time to progression and survival. Objective responses by Macdonald criteria on an intent to treat basis were 45% including complete response in three patients (7.5%), and partial response in 15 patients (37.5%). Responses were seen in biopsy-only patients (33.4%) as well as in partial surgery patients (52%). Median survival for all patients was 12.5 months. Biopsy-only patients had a median survival of 12.8 months. Grade 3 to 4 neutropenia was the most important toxicity, and occurred in 37.5% of patients. A delay in 18.2% and a dose reduction in 9.6% of cycles were necessary due to myelosuppression on day 28. Two patients had neutropenic fever resulting in one treatment-related death. Eighty-two percent of patients received radiotherapy. CONCLUSION: This regimen has significant activity, as it induces objective responses even in biopsy-only patients, appearing to improve their median survival. A better combination schedule is needed to improve the toxicity profile.

Adult↗
PubMed2003

Increasing-dose gemcitabine plus low-dose cisplatin in metastatic non-small cell lung cancer.

UNLABELLED: Gemcitabine, a pyrimidine analog active in non-small cell lung cancer (NSCLC), is widely used with cisplatin. The potential activity of the combination has not been fully assessed: gemcitabine is not used at its maximum tolerated dose (MTD) and cisplatin shows a clearly dose-related toxicity. This trial was designed to assess the MTD and dose-limiting toxicity (DLT) of low-dose cisplatin and increasing gemcitabine dose. CHEMOTHERAPY: cisplatin 50 mg/m2 on day 1, gemcitabine starting at 1400 mg/m on days 1 and 8 every 21 days. Subsequent levels were increased by 200 mg/m2. Forty-two patients with metastatic NSCLC were enrolled (37 males; median age 61 years; squamous cell carcinoma 19 patients; performance status 2, in 13 patients; 18 patients had significant weight loss). MTD was found to be 2600 mg/m2 because of DLT in three of six patients: two neutropenic fever and one massive bleeding. Overall toxicity was generally mild consisting mainly of neutropenia. Asthenia was the most common non-hematological effect. Overall response rate was 19 out of 41 patients (46.3%) and median survival was 31 weeks. We conclude that the recommended dose for a phase II dose is gemcitabine 2400 mg/m2 days 1 and 8 as a 30-min infusion when given with cisplatin 50 mg/m2.

Adenocarcinoma↗
PubMed2003

Weekly docetaxel as neoadjuvant chemotherapy for stage II and III breast cancer: efficacy and correlation with biological markers in a phase II, multicenter study.

PURPOSE: This is one of the first reports of weekly docetaxel (Taxotere) in the neoadjuvant treatment of stage II and III breast cancer. We evaluated docetaxel's efficacy and safety and analyzed correlations between response and the expression of c-erbB2, ER status, and Ki-67 labeling index. EXPERIMENTAL DESIGN: Patients with previously untreated, stage II and III breast cancer were entered into the study. Docetaxel (40 mg/m(2)) was given i.v. once weekly for the first 6 weeks of an 8-week cycle for 2 cycles. RESULTS: A total of 56 patients were evaluated by intention-to-treat analysis for efficacy and safety. The overall clinical response rate was 68% (complete and partial response, 29 and 39%, respectively). Nine patients (16%) achieved a pathological complete response. There was no correlation between response to docetaxel and the expression of molecular markers, however, the majority of the pathological complete responses were observed in patients with c-erbB2-negative tumors. Nonhematological toxicity was more common than hematological toxicity, with alopecia and asthenia the most frequently reported adverse events (89 and 77% of patients, respectively). Severe hematological toxicity was rare. CONCLUSIONS: Weekly docetaxel appears to be very effective in the neoadjuvant setting. A high pathological response rate was achieved with tolerable toxicity.

Adult↗
PubMedDate not supplied

Serum markers and prognosis in locally advanced breast cancer.

BACKGROUND: Locally advanced breast cancer (LABC) represents a heterogeneous subgroup of breast cancer with an often dismal outcome. Identifying prognostic factors has acquired great significance for the selection of optimal treatment in individual patients. METHODS: Between January 1993 and December 1997, 103 patients were treated in our institution with multimodality treatment consisting of neoadjuvant chemotherapy followed by surgery, adjuvant chemotherapy and radiotherapy; tamoxifen was added in hormone receptor-positive cases. In the search for prognostic factors well-established parameters (clinical, pathological and treatment-related) as well as new features with potential value (c-erbB-2, baseline serum levels of CA 15.3 and CEA) were included in the univariate and multivariate analysis. RESULTS: At a median follow-up of 92 months (range, 8-130), the estimated five-year cancer-specific overall survival (OS) and disease-free survival (DFS) were 71.34% and 57.7%, respectively. Among the 22 different variables studied, only 10 were significantly correlated with OS and DFS. In multivariate analysis five retained independent prognostic value for both OS and DFS: tumor grade, serum markers, features of inflammatory breast cancer (IBC), response to neoadjuvant chemotherapy and lymph node status. With cutoff values of 35 U/mL for CA 15.3 and 5 ng/mL for CEA, the probability of five-year OS (Cox hazard ratio 3.91, P = 0.0009) and DFS (Cox hazard ratio 2.40, P = 0.02) decreased from 78% to 52% and from 68% to 47%, respectively, when at least one of these markers was abnormal. CONCLUSIONS: Baseline serum levels of CEA and CA 15.3 emerged from this study as strong independent predictors of outcome in LABC, whose value adds to other established prognostic factors such as postoperative nodal status, IBC, histological grade and response to neoadjuvant chemotherapy.

Adult↗