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981.
The role of 18F-FDG-PET in the local/regional evaluation of women with breast cancer 总被引:8,自引:0,他引:8
Danforth DN Aloj L Carrasquillo JA Bacharach SL Chow C Zujewski J Whatley M Galen B Merino M Neumann RD 《Breast cancer research and treatment》2002,75(2):135-146
Purpose. In women with breast cancer, knowledge of the local/regional extent of the tumor is essential for staging, treatment planning, monitoring response to therapy, and follow-up. Positron emission tomography (PET) is an important imaging test which can detect tumor at multiple sites in women with breast cancer. We compared the ability of PET to provide a comprehensive view of the local/regional extent of tumor in women with stage I, II and stage III, IV breast cancer.
Materials and methods. Forty-six women with breast cancer underwent PET using 18F-FDG. 18FDG uptake in the breast primary tumor, associated skin, axillary and internal mammary lymph nodes, and the contralateral breast was determined qualitatively, and correlated with histologic, clinical and radiographic findings.
Results. Twenty-four patients were premenopausal and 22 were postmenopausal, with the following distribution according to clinical stage: stage I – 2 patients, stage II – 16, stage III – 16, stage IV – 12 patients. Among stage I, II patients, the sensitivity for detection of the primary tumor was 83.3%, and for detection of axillary lymph node metastases was 42.9%. 18FDG-PET was negative for the breast skin, contralateral breast, and internal mammary lymph nodes in all stage I, II patients, in agreement with clinical and radiographic findings. Among 28 stage III, IV patients, the sensitivity of 18FDG-PET for detection of the primary tumor was 90.5%, and for detection of axillary lymph node metastases 83.3%. Fourteen patients had clinically advanced changes in the skin, and the sensitivity of PET for detection of skin changes was 76.9%. 18FDG-PET was positive in the internal mammary lymph nodes in 25.0%, and negative in the contralateral breast in all patients with stage III, IV breast cancer. 18FDG-PET was studied in 10 patients following neoadjuvant chemotherapy, and showed a strong correlation with clinical response, and with clinical and pathological findings post-treatment at multiple local/regional sites.
Conclusion.
18FDG-PET can provide a comprehensive image of local/regional tumor in women with breast cancer. 18FDG-PET may play a greater role in women with stage III, IV breast cancer because of increased sensitivity and the increased involvement of multiple local/regional sites with tumor. 相似文献
982.
De Leon Matsuda ML Liede A Kwan E Mapua CA Cutiongco EM Tan A Borg A Narod SA 《International journal of cancer. Journal international du cancer》2002,98(4):596-603
Age-adjusted incidence rates of breast cancer vary more than 10-fold worldwide, with the highest rates reported in North America and Europe. The highest breast cancer incidence rates in Southeast Asia have been reported for the Manila Cancer Registry in the Philippines, with an age-standardized rate of 47.7 per 100,000 per year. The possible contribution of hereditary factors to these elevated rates has not been investigated. We conducted a case-control study of 294 unselected incident breast cancer cases and 346 female controls from Manila, Philippines. Cases and controls were selected from women below the age of 65 undergoing evaluation at the PGH in Manila because of a suspicious breast mass. Molecular analysis identified 12 BRCA2 mutations and 3 BRCA1 mutations. We estimate the prevalence of BRCA mutations among unselected breast cancer cases in the Philippines to be 5.1% (95% CI: 2.6-7.6%), with a prevalence of 4.1% (95% CI: 1.8-6.4%) for BRCA2 mutations alone. The BRCA2 4265delCT and 4859delA mutations were found in 2 and 4 unrelated cases, respectively; haplotype analysis confirmed that these, and the BRCA1 5454delC mutation, are founder mutations. BRCA2 mutations were also found in 2 of 346 controls (0.6%; 95% CI: 0.2-1.4%). Compared with non-carrier cases, the cumulative risk of breast cancer for first-degree relatives of mutation carriers was 24.3% to age 50, compared with <4% for first-degree relatives of non-carrier cases (RR = 6.6; 95% CI: 2.6-17.2; p= 7.5 x 10(-6)). Our data suggest that penetrance of BRCA mutations is not reduced in the Philippines. Germline mutations in the BRCA2 gene contribute more than mutations BRCA1 to breast cancer in the Philippines, due in large part to the presence of 2 common founder mutations. 相似文献
983.
Xiaoying Liang Dandan Zheng Maria Mamalui-Hunter Stella Flampouri Bradford S. Hoppe Nancy Mendenhall Zuofeng Li 《Practical radiation oncology》2019,9(1):38-48
Purpose
Using planning target volume (PTV) to account for setup uncertainties in stereotactic body radiation therapy (SBRT) of lung cancer has been questioned because a significant portion of the PTV contains low-density lung tissue. The purpose of this study is to (1) investigate the feasibility of using robust optimization to account for setup uncertainties in volumetric modulated arc therapy plan for lung SBRT and (2) evaluate the potential normal tissue–sparing benefit of a robust optimized plan compared with a conventional PTV-based optimized plan.Methods and materials
The study was conducted with both phantom and patient cases. For each patient or phantom, 2 SBRT lung volumetric modulated arc therapy plans were generated, including an optimized plan based on the PTV (PTV-based plan) with a 5-mm internal target volume (ITV)-to-PTV margin and a second plan based on robust optimization of ITV (ITV-based plan) with ±5-mm setup uncertainties. The target coverage was evaluated on ITV D99 in 15 scenarios that simulated a 5-mm setup error. Dose-volume information on normal lung tissue, intermediate-to-high dose spillage, and integral dose was evaluated.Results
Compared with PTV-based plans, ITV-based robust optimized plans resulted in lower normal lung tissue dose, lower intermediate-to-high dose spillage to the body, and lower integral dose, while preserving the dose coverage under setup error scenarios for both phantom and patient cases.Conclusions
Using ITV-based robust optimization, we have shown that accounting for setup uncertainty in SBRT planning is feasible. Further clinical studies are warranted to confirm the clinical effectiveness of this novel approach. 相似文献984.
985.
Munzone E Nolé F Goldhirsch A Botteri E Esposito A Zorzino L Curigliano G Minchella I Adamoli L Cassatella MC Casadio C Sandri MT 《Clinical breast cancer》2010,10(5):392-397
BackgroundHER2/neu status of tumor cells at metastatic sites in patients with advanced disease may differ from that of the primary tumor. Assessing the presence of target antigens on circulating tumor cells (CTCs) might affect treatment choice.Patients and MethodsFrom June 2007 to October 2008, we collected 23 mL of blood from each of the 76 consecutive patients before and during chemotherapy to determine CTC numbers and HER2 overexpression. CTCs were isolated with the CellSearch System® (Veridex, LLC; Raritan, NJ) and fluorescently stained with the Epithelial Cell Kit®. Tumor Phenotyping Reagent® was used to investigate HER2/neu overexpression.ResultsConcordance of HER2 status between the primary tumor and CTCs was 86% (49 out of 57 patients) at baseline and 82% (50 out of 61 patients) in the treatment samples. HER2 overexpression in CTCs was acquired in 8 out of 45 patients (18%) and lost in 3 out of 16 patients (19%) during a treatment containing trastuzumab. The overall discordance rate between the primary tumor and CTCs was 18% (11 out of 61 patients). Patients with HER2 overexpression in CTCs had poorer progression-free survival compared with those without CTCs or with HER2? CTCs (log-rank P =.036).ConclusionInformation on the presence or absence of HER2 overexpression can be obtained in CTCs. Larger trials are needed to evaluate the activity of HER2-targeted therapy in patients with acquired HER2 overexpression in CTCs. 相似文献
986.
987.
988.
Tampellini M Berruti A Bitossi R Gorzegno G Alabiso I Bottini A Farris A Donadio M Sarobba MG Manzin E Durando A Defabiani E De Matteis A Ardine M Castiglione F Danese S Bertone E Alabiso O Massobrio M Dogliotti L 《Breast cancer research and treatment》2006,98(3):241-248
Summary Tumor response to first-line chemotherapy in advanced breast cancer offers prognostic information and may be used as a surrogate marker for evaluating treatment efficacy. With this study we wanted to determine whether changes in circulating serum CA 15-3 levels during chemotherapy provided additional information for prognostic prediction. Serum CA 15-3 was measured at baseline and after 3 and 6 months during anthracycline-based first-line chemotherapy in 526 patients with advanced breast cancer prospectively enrolled in five phase II-III trials. Changes in marker levels were correlated with disease response, time to progression and overall survival. In all, 336 patients attained a disease response. A significant relationship was found between disease response and CA 15-3 variations, although many individual discrepancies were also observed. At the 6-month time point, the median time to progression was 15.3 months in patients with normal marker levels throughout the study, 11.7 months in those with a CA15-3 reduction >25%, 9.6 months in those with elevated baseline CA 15-3 levels which did not change during therapy and 8.6 months in those with increased marker levels (p < 0.001). The median survival was 42.3, 29.7, 28.5, and 24.8 months, respectively (p < 0.002). The prognostic role of changes in CA 15-3 levels was maintained in the patient subset attaining disease response or stabilization to treatment (p < 0.001) and after adjusting for clinical response and major prognostic parameters in the multivariate analysis (p < 0.001). In conclusion, monitoring serum CA 15-3 levels during first-line chemotherapy in advanced breast cancer patients provides prognostic information independently from tumor response. 相似文献
989.
Federica Perrone Simona Suardi Elisa Pastore Paola Casieri Marta Orsenigo Stefano Caramuta Gianpaolo Dagrada Marco Losa Lisa Licitra Paolo Bossi Samantha Staurengo Maria Oggionni Laura Locati Giulio Cantu Massimo Squadrelli Antonino Carbone Marco A Pierotti Silvana Pilotti 《Clinical cancer research》2006,12(22):6643-6651
PURPOSE: The aim of this study was to acquire further insights into the pathogenetic pathways of head and neck squamous cell carcinomas (HNSCC) that may be useful for identifying new biomarkers instrumental in developing more specific treatment approaches. EXPERIMENTAL DESIGN: Cell cycle regulators and epidermal growth factor receptor (EGFR) and BRAF genes were analyzed in a series of 90 oropharyngeal SCCs of a cohort of surgically treated patients from a single institution, and the results were matched with the presence of high-risk human papillomavirus (HR-HPV) DNA and the TP53 status. RESULTS: At least four distinct groups of tumors were identified sharing a common histology but displaying different molecular/cytogenetic patterns: (a) 19% were HPV-positive SCCs whose lack of alterations of the investigated genes could explain their particular natural history, which requires less aggressive treatment; (b) 37% were HPV-negative SCCs carrying TP53 mutations, which may be more effectively treated by drugs acting through p53-independent apoptosis; (c) 34% were HPV-negative SCCs carrying wild-type TP53 and loss of 9p21 (p16INK4a and p15INK4b) and/or cyclin D1 overexpression that justify treatment with DNA-damaging drugs followed by cell cycle inhibitors; and (d) 10% were HPV-negative lacking tumor suppressor genes and cell cycle alterations. The second, third, and fourth groups also showed an increased copy number of EGFR and chromosome 7 (43%) that might justify the additional or alternative use of EGFR inhibitors. CONCLUSIONS: Our findings suggest that assessing HPV, TP53, 9p21, and EGFR status may be crucial to finding more tailored and beneficial treatments for oropharyngeal SCCs. 相似文献
990.
Pantalone O Palladino F Lotito RM Missere M Savino G Minella G Meduri A Natale L Marano P 《Rays》2003,28(1):13-19
The introduction of spiral multislice or multidetector CT (MSCT) has led to significant results in coronary diagnostic imaging. In fact with MSCT, isotropic (cubic voxel) three-dimensional imaging of large volumes (e.g. the entire cardiac volume) was possible in a single breath-hold. Moreover, with dedicated reconstruction algorithms, temporal resolution and scannable volume could be optimized, limiting the artifacts associated with the spiral technique. The quantification of calcium deposits in the coronary walls and, in particular, the morphologic study of these vessels represent an important challenge to this technique. Multislice CT with retrospective gating is now a relevant diagnostic instrument in coronary heart disease; however only most recent CT devices with 16 rows of detectors enable a real solution of problems of spatial (isotropic, submillimetric imaging) and temporal (< 0.5 s rotation time) required for correct identification of stenosis and plaque characterization, which are the two main goals of noninvasive coronary imaging. 相似文献