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1.
Clin Transl Radiat Oncol ; 34: 82-89, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35372703

RESUMO

Purpose: This R-Ideal stage 1b/2a study describes the workflow and feasibility of long-course fractionated online adaptive MR-guided chemoradiotherapy with reduced CTV-to-PTV margins on the 1.5T MR-Linac for patients with esophageal cancer. Methods: Patients with esophageal cancer scheduled to undergo chemoradiation were treated on a 1.5T MR-Linac. Daily MR-images were acquired for online contour adaptation and replanning. Contours were manually adapted to match the daily anatomy and an isotropic CTV-to-PTV margin of 6 mm was applied. Time was recorded for all individual steps in the workflow. Feasibility and patient tolerability were defined as on-table time of ≤60 min and completion of >95% of the fractions on the MR-Linac, respectively. Positioning verification and post-treatment MRIs were retrospectively analyzed and dosimetric parameters were compared to standard non-adaptive conventional treatment plans. Results: Nine patients with esophageal cancer were treated with chemoradiation; eight patients received 41.4 Gy in 23 fractions and one received 50.4 Gy in 28 fractions. Four patients received all planned fractions on the MR-Linac, whereas for two patients >5% of fractions were rescheduled to a conventional linac for reasons of discomfort. A total of 183 (86%) of 212 scheduled fractions were successfully delivered on the MR-Linac. Three fractions ended prematurely due to technical issues and 26 fractions were rescheduled on a conventional linac due to MR-Linac downtime (n = 10), logistical reasons (n = 3) or discomfort (n = 13).The median time per fraction was 53 min (IQR = 3 min). Daily adapted MR-Linac plans had similar target coverage, whereas dose to the organs-at-risk was significantly reduced compared to conventional treatment (26% and 12% reduction in mean lung and heart dose, respectively). Conclusion: Daily online adaptive fractionated chemoradiotherapy with reduced PTV margins is moderately feasible for esophageal cancer and results in better sparing of heart and lungs. Future studies should focus on further optimization and acceleration of the current workflow.

2.
J Gastrointest Surg ; 25(1): 67-76, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33140322

RESUMO

INTRODUCTION: After endoscopic resection (ER) of neoplasia in Barrett's esophagus (BE), it is recommended to ablate the remaining BE to minimize the risk for metachronous disease. However, we report long-term outcomes for a nationwide cohort of all patients who did not undergo ablation of the remaining BE after ER for early BE neoplasia, due to clinical reasons or performance status. METHODS: Endoscopic therapy for BE neoplasia in the Netherlands is centralized in 8 expert centers with specifically trained endoscopists and pathologists. Uniformity is ensured by a joint protocol and regular group meetings. We report all patients who underwent ER for a neoplastic lesion between 2008 and 2018, without further ablation therapy. Outcomes include progression during endoscopic FU and all-cause mortality. RESULTS: Ninety-four patients were included with mean age 74 (± 10) years. ER was performed for low-grade dysplasia (LGD) (10%), high-grade dysplasia (HGD) (25%), or low-risk esophageal adenocarcinoma (EAC) (65%). No additional ablation was performed for several reasons; in 73 patients (78%), the main argument was expected limited life expectancy. Median C2M5 BE persisted after ER, and during median 21 months (IQR 11-51) with 4 endoscopies per patient, no patient progressed to advanced cancer. Seventeen patients (18%) developed HGD/EAC: all were curatively treated endoscopically. In total, 29/73 patients (40%) with expected limited life expectancy died due to unrelated causes during FU, none of EAC. CONCLUSION: In selected patients, ER monotherapy with endoscopic surveillance of the residual BE is a valid alternative to eradication therapy with ablation.


Assuntos
Adenocarcinoma , Esôfago de Barrett , Ablação por Cateter , Neoplasias Esofágicas , Lesões Pré-Cancerosas , Adenocarcinoma/cirurgia , Idoso , Esôfago de Barrett/cirurgia , Neoplasias Esofágicas/cirurgia , Esofagoscopia , Humanos , Países Baixos/epidemiologia , Lesões Pré-Cancerosas/cirurgia
3.
Ann Oncol ; 25(5): 998-1004, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24585721

RESUMO

BACKGROUND: The role of zoledronic acid (ZA) when added to the neoadjuvant treatment of breast cancer (BC) in enhancing the clinical and pathological response of tumors is unclear. The effect of ZA on the antitumor effect of neoadjuvant chemotherapy has not prospectively been studied before. PATIENTS AND METHODS: NEOZOTAC is a national, multicenter, randomized study comparing the efficacy of TAC (docetaxel, adriamycin and cyclophosphamide i.v.) followed by granulocyte colony-stimulating factor on day 2 with or without ZA 4 mg i.v. q 3 weeks inpatients withstage II/III, HER2-negative BC. We present data on the pathological complete response (pCR in breast and axilla), on clinical response using MRI, and toxicity. Post hoc subgroup analyses were undertaken to address the predictive value of menopausal status. RESULTS: Addition of ZA to chemotherapy did not improve pCR rates (13.2% for TAC+ZA versus 13.3% for TAC). Postmenopausal women (N = 96) had a numerical benefit from ZA treatment (pCR 14.0% for TAC+ZA versus 8.7% for TAC, P = 0.42). Clinical objective response did not differ between treatment arms (72.9% versus 73.7%). There was no difference in grade III/IV toxicity between treatment arms. CONCLUSIONS: Addition of ZA to neoadjuvant chemotherapy did not improve pathological or clinical response to chemotherapy. Further investigations are warranted in postmenopausal women with BC, since this subgroup might benefit from ZA treatment.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Receptor ErbB-2/metabolismo , Adulto , Idoso , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Quimioterapia Adjuvante , Ciclofosfamida/administração & dosagem , Difosfonatos/administração & dosagem , Docetaxel , Doxorrubicina/administração & dosagem , Feminino , Humanos , Imidazóis/administração & dosagem , Pessoa de Meia-Idade , Terapia Neoadjuvante , Estadiamento de Neoplasias , Estudos Prospectivos , Taxoides/administração & dosagem , Resultado do Tratamento , Ácido Zoledrônico
4.
Cancer Res ; 74(4): 979-1004, 2014 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-24514041

RESUMO

Photoacoustic imaging (PAI) has the potential for real-time molecular imaging at high resolution and deep inside the tissue, using nonionizing radiation and not necessarily depending on exogenous imaging agents, making this technique very promising for a range of clinical applications. The fact that PAI systems can be made portable and compatible with existing imaging technologies favors clinical translation even more. The breadth of clinical applications in which photoacoustics could play a valuable role include: noninvasive imaging of the breast, sentinel lymph nodes, skin, thyroid, eye, prostate (transrectal), and ovaries (transvaginal); minimally invasive endoscopic imaging of gastrointestinal tract, bladder, and circulating tumor cells (in vivo flow cytometry); and intraoperative imaging for assessment of tumor margins and (lymph node) metastases. In this review, we describe the basics of PAI and its recent advances in biomedical research, followed by a discussion of strategies for clinical translation of the technique.


Assuntos
Imagem Molecular/métodos , Neoplasias/diagnóstico , Técnicas Fotoacústicas , Pesquisa Translacional Biomédica/tendências , Animais , Corantes , Meios de Contraste , Técnicas de Diagnóstico Obstétrico e Ginecológico , Técnicas de Diagnóstico Urológico , Detecção Precoce de Câncer/métodos , Feminino , Humanos , Masculino
5.
Cancer Treat Rev ; 37(6): 422-30, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21177040

RESUMO

Neoadjuvant chemotherapy (NAC) for breast cancer is evolving and subsequent adjuvant systemic treatment is mainly based on the presence of the Estrogen (ER) receptor, Progesterone (PR) receptor and Human Epidermal growth factor Receptor 2 (HER2) status on the core needle biopsy prior to treatment. It is not well known whether these biomarkers change after NAC, requiring a change in further adjuvant systemic treatment. A review of the literature (PubMed search) revealed 32 relevant studies that investigated the concordance of the hormone receptors (ER and/or PR) and HER2 after NAC with or without trastuzumab. Discordance of the hormone receptor status was reported in four out of eight studies in 8-33% of the patients. About half of the studies that tested the ER and PR receptor status separately reported discordances of 2.5-17% and 5.9-51.7% respectively. Studies that concluded that ER and/or PR receptor remained stable after NAC were performed with evidently lower number of patients compared to studies that reported a change. Good concordance of the HER2 amplification tested with FISH was reported, although the HER2 expression measured with immunohistochemistry was more discordant. A switch to a negative HER2 receptor in up to 43% of the patients was reported when NAC was combined with trastuzumab. Until more comparable studies are being published, retesting the receptor status of the residual tumor after NAC should be considered in order to improve future tailored adjuvant therapies.


Assuntos
Antineoplásicos/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/metabolismo , Terapia Neoadjuvante , Receptor ErbB-2/metabolismo , Receptores de Estrogênio/metabolismo , Receptores de Progesterona/metabolismo , Biomarcadores Tumorais/metabolismo , Feminino , Humanos , Prognóstico
6.
Eur J Surg Oncol ; 35(6): 573-7, 2009 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-18986790

RESUMO

AIM: Preoperative stratification of patients presenting with nipple discharge (ND) according to malignancy risk has proven difficult. Nevertheless, cytological examination is considered to be a diagnostic aid. The aim of this study was to determine its complementary value in clinical decision-making in patients presenting with ND. METHODS: We retrospectively collected data on macroscopic ND colour, ND cytology, physical examination, mammography, ultrasound and fine-needle aspiration cytology results. On ND cytology, benign diagnoses were considered negative, whereas suspicious and malignant diagnoses were considered positive for malignancy. RESULTS: From 1992 to 2006, 618 patients had an ND smear, of those 163 patients had a biopsy. Sensitivity and specificity were 16.7% and 66.1%, respectively. These values were lower when ND was bloody than when ND was non-bloody (p=0.66 and p<0.05 for sensitivity and specificity, respectively). When macroscopically defining bloody ND as positive and non-bloody ND as negative, macroscopic ND colour examination had a remarkably higher sensitivity (60.6 vs. 18.2%, p<0.001) and only a slightly lower specificity (53.6 vs. 65.0%, p=0.07) when compared to cytological ND examination. Only 1 malignant lesion was designated positive solely by ND cytology (unique sensitivity (95% CI), 2.8% (0.0-8.4%)) and 3 lesions were correctly classified as negative by ND cytology (unique specificity (95% CI), 1.6%, 0.0-3.7%)). CONCLUSION: Nipple discharge cytology has little complementary diagnostic value. Therefore, its routine use for detection of ND-related breast pathology should be reconsidered carefully. Nipple discharge cytology may redirect patient management well in some cases, but it may confuse work-up in the majority.


Assuntos
Neoplasias da Mama/patologia , Exsudatos e Transudatos/citologia , Mamilos/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias da Mama/diagnóstico , Neoplasias da Mama Masculina/diagnóstico , Neoplasias da Mama Masculina/patologia , Feminino , Humanos , Masculino , Mamografia , Pessoa de Meia-Idade , Estudos Retrospectivos , Adulto Jovem
7.
Cancer Imaging ; 8: 206-15, 2008 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-19028613

RESUMO

This review provides a summary of the current state of optical breast imaging and describes its potential future clinical applications in breast cancer imaging. Optical breast imaging is a novel imaging technique that uses near-infrared light to assess the optical properties of breast tissue. In optical breast imaging, two techniques can be distinguished, i.e. optical imaging without contrast agent, which only makes use of intrinsic tissue contrast, and optical imaging with a contrast agent, which uses exogenous fluorescent probes. In this review the basic concepts of optical breast imaging are described, clinical studies on optical imaging without contrast agent are summarized, an outline of preclinical animal studies on optical breast imaging with contrast agents is provided, and, finally, potential applications of optical breast imaging in clinical practice are addressed. Based on the present literature, diagnostic performance of optical breast imaging without contrast agent is expected to be insufficient for clinical application. Development of contrast agents that target specific molecular changes associated with breast cancer formation is the opportunity for clinical success of optical breast imaging.


Assuntos
Neoplasias da Mama/diagnóstico , Neoplasias da Mama/terapia , Meios de Contraste , Diagnóstico por Imagem/métodos , Feminino , Humanos , Espectroscopia de Luz Próxima ao Infravermelho/métodos , Resultado do Tratamento
8.
J Appl Microbiol ; 84(6): 1059-68, 1998 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-9717291

RESUMO

Four Streptococcus thermophilus strains (Strep. thermophilus BTC, Strep. thermophilus LY03, Strep. thermophilus 480 and Strep. thermophilus Sfi20) have been examined for their exopolysaccharide production capacity. All strains produced a polymer composed of the neutral sugars glucose and galactose, but in different ratios. It was clearly shown that the biosynthesis of exopolysaccharides from Strep. thermophilus LY03 is growth-associated and hence displays primary metabolite kinetics. The monomer ratio of the exopolysaccharide synthesized did not vary throughout the fermentation cycle. The production kinetics and exopolysaccharide yields were strongly dependent on the fermentation conditions. Physical factors such as temperature, pH and oxygen tension as well as chemical factors (medium composition, initial lactose concentration, carbon/nitrogen levels) were of utmost importance.


Assuntos
Polissacarídeos Bacterianos/biossíntese , Polissacarídeos Bacterianos/isolamento & purificação , Streptococcus/metabolismo , Animais , Carbono/farmacologia , Meios de Cultura , Fermentação , Concentração de Íons de Hidrogênio , Cinética , Lactose/farmacologia , Leite , Nitrogênio/farmacologia , Polissacarídeos Bacterianos/análise , Streptococcus/crescimento & desenvolvimento , Temperatura
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