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MATERIAL AND METHODS: Retrospective multi-center analysis of women diagnosed with borderline ovarian tumor and treated between January 1990 and December 1997. A national survey was conducted, in which 457 patients from 27 centers corresponding to ten of Spain's autonomous communities were analyzed. RESULTS: Four hundred fifty-seven women with borderline ovarian tumor were analyzed. The mean age of patients was 45.5+/-16.9 years. Of these, 390 patients (85.3%) were at stage I, 8 (1.8%) were at stage II and 36 (7.9%) at stage III. A bilateral tumor was observed in 63 women (13.8%). The mean tumor size was 14.2 cm and in 88 cases (19.3%) the tumor was on the surface of the ovary. Microinvasion was observed in 25 (5.5%) cases, and 29 women (6.3%) showed a micropapillary pattern. Study of the factors related to the appearance of peritoneal implants revealed positive tumor markers (OR 15.02: 1.9-32.9) and a tumor on the ovarian surface (OR 8.0: 1.8-127) to be independent risk factors. With respect to recurrence, the presence of peritoneal implants at the time of initial surgery (OR 3.4: 1.1-10.4) and signs of microinvasion in the anatomicopathological study (OR 5.5: 1.5-17.8) were found to be independent risk factors. The overall survival rate in our series was 97% with a mean follow-up of 88.3 months. The survival rate by stage was 97% for stage I, 100% for stage II and 97% for stage III. CONCLUSIONS: Although borderline ovarian tumors have an excellent prognosis, they are not exempt from a risk of recurrence. Characterization of patients with borderline ovarian tumor is essential in order to prevent their evolution. Likewise, the taking on board of risk factors will enable more selective treatments to be offered in each case.  相似文献   
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Background Biliary tract cancers (BTC) are rare but highly aggressive tumours with poor prognosis, usually detected at advanced stages. Herein, we aimed at identifying BTC-specific DNA methylation alterations.Methods Study design included statistical power and sample size estimation. A genome-wide methylation study of an explorative cohort (50 BTC and ten matched non-tumoral tissue samples) has been performed. BTC-specific altered CpG islands were validated in over 180 samples (174 BTCs and 13 non-tumoral controls). The final biomarkers, selected by a machine-learning approach, were validated in independent tissue (18 BTCs, 14 matched non-tumoral samples) and bile (24 BTCs, five non-tumoral samples) replication series, using droplet digital PCR.Results We identified and successfully validated BTC-specific DNA methylation alterations in over 200 BTC samples. The two-biomarker panel, selected by an in-house algorithm, showed an AUC > 0.97. The best-performing biomarker (chr2:176993479-176995557), associated with HOXD8, a pivotal gene in cancer-related pathways, achieved 100% sensitivity and specificity in a new series of tissue and bile samples.Conclusions We identified a novel fully efficient BTC biomarker, associated with HOXD8 gene, detectable both in tissue and bile by a standardised assay ready-to-use in clinical trials also including samples from non-invasive matrices.Subject terms: Diagnostic markers, Biliary tract cancer  相似文献   
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The aim of this study was to evaluate the applicability of different calibration approaches in trichothecenes analysis from wheat flour. Concretely eight trichothecenes (five type B trichothecenes and three type A trichothecenes) were analyzed by matrix solid-phase dispersion (MSPD) and liquid chromatography–tandem mass spectrometry (LC–MS/MS). In the first set of experiments the presence of matrix effects was evaluated; values ranged between 59% and 79%. In the second set of experiments, solutions to compensate these signal suppressions were examined. Different calibration methods showed to tackle matrix effects obtaining values between 69% and 85% for external matrix matched calibration and values from 76% to 111% and from 78% to 108% by analog and deuterated internal standard calibrations, respectively. Trueness of the method was studied using quality control material and certificated reference material (DON 1062 ± 110 μg kg−1). The values were compared by matrix-matched, analog internal standard (deepoxydeoxynivalenol (DOM-1)) and deuterated internal standard (DON-d1).  相似文献   
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