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1.
Microscopy (Oxf) ; 2024 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-38527311

RESUMO

Chlamydia psittaci is an avian bacterial pathogen that can cause atypical pneumonia in humans via zoonotic transmission. It is a Gram-negative intracellular bacterium that proliferates inside membrane bound inclusions in the cytoplasm of living eukaryotic cells. The study of such cells with C. psittaci inside without destroying them poses a significant challenge. We demonstrated in this work the utility of a combined multitool approach to analyze such complex samples. Atomic force microscopy was applied to obtain high-resolution images of the surface of infected cells upon entrance of bacteria. Atomic force microscopy scans revealed the morphological changes of the cell membrane of Chlamydia infected cells such as changes in roughness of cell membrane and the presence of micro vesicles. 4Pi Raman microscopy was used to image and probe the molecular composition of intracellular bacteria inside intact cells. Information about the structure of the inclusion produced by C. psittaci was obtained and it was found to have a similar molecular fingerprint as that of an intracellular lipid droplet but with less proteins and unsaturated lipids. The presented approach demonstrates complementarity of various microscopy-based approaches and might be useful for characterization of intracellular bacteria.

2.
Brachytherapy ; 17(1): 208-213, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29113782

RESUMO

PURPOSE: The aim of this study was to evaluate the interobserver variability (IOV) of rectum contouring, and its dosimetric consequences, for high-dose-rate brachytherapy in patients with prostate cancer across multiple institutions. METHODS AND MATERIALS: Five radiation oncologists contoured rectums in 10 patients on transperineal ultrasound image sets after establishing a delineation consensus. The D0.1cc, D1cc, and D2cc rectum volume parameters were determined. The mean, standard deviation, and range of each dose-volume histogram parameter were evaluated for each patient. The IOV was determined using the coefficient of variation, and the dosimetric impacts on the total dose were analyzed by estimating the biologically equivalent dose (EQD2α/ß = 3). RESULTS: The interobserver coefficients of variation (±standard deviation) for the reported D0.1cc, D1cc, and D2cc were 5 ± 1.84%, 4 ± 1.26%, and 4 ± 1.33%, respectively. As for the impact on the total dose, the mean dose differences for D0.1cc, D1cc, and D2cc were 10 Gy, 7.3 Gy, and 6.6 Gy, respectively. CONCLUSIONS: The D2cc is robust as evident by the low IOV (<5%). However, some variability ranges almost overlap with the clinical threshold level, which may present dosimetric and clinical complications. General rectal contouring guidelines for prostate high-dose-rate brachytherapy are desirable to reduce discrepancies in delineation.


Assuntos
Braquiterapia/métodos , Órgãos em Risco , Neoplasias da Próstata/radioterapia , Reto/anatomia & histologia , Reto/diagnóstico por imagem , Endossonografia , Humanos , Masculino , Variações Dependentes do Observador , Tamanho do Órgão , Estudos Prospectivos , Doses de Radiação , Dosagem Radioterapêutica , Planejamento da Radioterapia Assistida por Computador
3.
Opt Lett ; 42(21): 4410-4413, 2017 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-29088176

RESUMO

The advent of 4π microscopy broke the conventional optical resolution limit in the axial direction of the microscope. In combination with fluorescence microscopy, it broadened the knowledge of cell biology at the expense of perturbing the samples with extrinsic fluorescent labels. In contrast, Raman microscopy acquires the molecular fingerprint of the sample without the need of extrinsic labels, and therefore improving its resolution can make an even greater impact. Here, we take advantage of the improved axial resolution of a 4π configuration to form a 4π Raman microscope. With this microscope, we independently and simultaneously analyzed different nanolayers in a multilayer stack. We identified their chemical composition and retrieved their relative subwavelength optical separation with a precision of 6 nm.

4.
Sci Adv ; 3(9): e1701151, 2017 09.
Artigo em Inglês | MEDLINE | ID: mdl-28929137

RESUMO

Structural colors enable the creation of a spectrum of nonfading colors without pigments, potentially replacing toxic metal oxides and conjugated organic pigments. However, significant challenges remain to achieve the contrast needed for a complete gamut of colors and a scalable process for industrial application. We demonstrate a feasible solution for producing structural colors inspired by bird feathers. We have designed core-shell nanoparticles using high-refractive index (RI) (~1.74) melanin cores and low-RI (~1.45) silica shells. The design of these nanoparticles was guided by finite-difference time-domain simulations. These nanoparticles were self-assembled using a one-pot reverse emulsion process, which resulted in bright and noniridescent supraballs. With the combination of only two ingredients, synthetic melanin and silica, we can generate a full spectrum of colors. These supraballs could be directly added to paints, plastics, and coatings and also used as ultraviolet-resistant inks or cosmetics.

5.
Brachytherapy ; 16(3): 511-517, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28366276

RESUMO

PURPOSE: To determine the significance of dose-volume histogram parameters for predicting late rectal toxicity (LRT) after single-fraction high-dose-rate brachytherapy (HDRBT) boost and external beam radiotherapy (EBRT) in prostate cancer. MATERIALS AND METHODS: Three hundred patients with intermediate- or high-risk prostate cancer were included between August 2010 and March 2015. Treatment comprised a single-fraction HDRBT boost of 15.0 Gy plus EBRT (46.0 Gy delivered in 23 fractions) or an HDRBT boost of 9.5 Gy plus EBRT (60.0 Gy delivered in 30 fractions) if the seminal vesicles were infiltrated using real-time transrectal ultrasound-based planning. LRT was evaluated every 3 months after the end of the combined treatment using the Common Terminology Criteria for Adverse Events, version 4.0. The minimum dose received by the most exposed 0.1 and 2.0 cm3 volume of the rectum (D0.1 cc/D2cc) was analyzed by estimating the biologically equivalent rectal dose according to the recommendations of the Groupe Européen de Curiethérapie/European Society for Radiotherapy and Oncology and an ordinal regression analysis was performed. RESULTS: LRT was observed in 62 patients (20.7%) at a median followup of 33 (range, 2-68) months. Twenty patients (6.7%) developed grade 2 and 3 patients (1%) developed grade 3 LRT. A significant association was observed between D2cc and the probability of developing grade 1-3 LRT (p = 0.04). CONCLUSIONS: D2cc is associated with the occurrence of LRT in HDRBT-treated prostate cancer patients. The dose constraints proposed and recommended by experienced HDRBT centers must be investigated to determine the threshold dose through long-term and prospective studies.


Assuntos
Braquiterapia/efeitos adversos , Órgãos em Risco/efeitos da radiação , Neoplasias da Próstata/radioterapia , Lesões por Radiação/etiologia , Reto/efeitos da radiação , Idoso , Idoso de 80 Anos ou mais , Braquiterapia/métodos , Terapia Combinada , Fracionamento da Dose de Radiação , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Planejamento da Radioterapia Assistida por Computador , Análise de Regressão , Fatores de Tempo
6.
J Contemp Brachytherapy ; 8(4): 344-8, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27648089

RESUMO

PURPOSE: Esteya and Valencia surface applicators are designed to treat skin tumors using brachytherapy. In clinical practice, in order to avoid errors that may affect the treatment outcome, there are two issues that need to be carefully addressed. First, the selected applicator for the treatment should provide adequate margin for the target, and second, the applicator has to be precisely positioned before each treatment fraction. In this work, we describe the development and use of a new acrylic templates named Template La Fe-ITIC. They have been designed specifically to help the clinical user in the selection of the correct applicator, and to assist the medical staff in reproducing the positioning of the applicator. These templates are freely available upon request. MATERIAL AND METHODS: Templates that were developed by University and Polytechnic Hospital La Fe (La Fe) and Hospital Clínica Benidorm (ITIC) in cooperation with Elekta, consist of a thin sheet made of transparent acrylic. For each applicator, a crosshair and two different circles are drawn on these templates: the inner one corresponds to the useful beam, while the outer one represents the external perimeter of the applicator. The outer circle contains slits that facilitate to draw a circle on the skin of the patient for exact positioning of the applicator. In addition, there are two perpendicular rulers to define the adequate margin. For each applicator size, a specific template was developed. RESULTS: The templates have been used successfully in our institutions for more than 50 patients' brachytherapy treatments. They are currently being used for Esteya and Valencia applicators. CONCLUSIONS: The template La Fe-ITIC is simple and practical. It improves both the set-up time and reproducibility. It helps to establish the adequate margins, an essential point in the clinical outcome.

7.
J Contemp Brachytherapy ; 8(4): 349-55, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27648090

RESUMO

PURPOSE: Groupe Européen de Curiethérapie (GEC) and European Society for Radiotherapy & Oncology (ESTRO) has proposed a rectal dose constraint of the most exposed 2-cc volume (D2cc of ≤ 75 Gy EQD2α/ß = 3) during external-beam plus high-dose-rate brachytherapy (HDR-BT) in localized prostate cancer patients. This study aimed to evaluate D2cc for rectal contouring via interobserver variability. MATERIAL AND METHODS: Four blinded observers contoured rectums of 5 patients. Rectal contouring anatomical limits were determined through previous consensus. Dose-volume histogram (DVH) dosimetric parameters (D0.1cc, D1cc, and D2cc) were analyzed according to GEC/ESTRO recommendations and subjected to intra- and interobserver comparisons. Latter comparisons involved coefficients of variation. For each parameter, the mean, standard deviation (SD), and range were evaluated. The effect of interobserver variation on total dose was analyzed by estimating the biologically equivalent rectal dose (EQD2α/ß = 3). RESULTS: Interobserver coefficients of variation for D0.1cc, D1cc, and D2cc were 5.7%, 4.5%, and 4%, respectively. The highest interobserver rectal delineation variation yielded a rectal dose difference up to 5.8 Gy EQD2. Estimated intraobserver variation for the reported D2cc was 5.5% in the worst-case scenario (non-significant). CONCLUSIONS: We observed acceptable interobserver variability in EQD2 for D2cc, with strong impacts on clinical threshold levels (D2cc ≤ 75 Gy EQD2) in some cases. This small, single-center analysis will be extended in a multicenter study.

8.
Cureus ; 8(4): e572, 2016 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-27190730

RESUMO

Synovial sarcoma (SS) is a high-grade, rare variant of soft tissue sarcoma (STS). The biphasic subtype is less common than the monophasic subtype. SS is very common around joint cavities in the extremities, but can be present elsewhere in the body. Tumor staging and therapeutic management are usually clear for a localized disease, but the proper management at the metastatic stage can be unclear. According to the literature, the histologic presence of an SS tumor thrombus affects tumor staging, making it unclear whether the tumor stage corresponds to localized or metastatic disease. An intravascular SS tumor exhibiting high metastatic potential is a rare finding that warrants thorough investigation. A 49-year-old woman presented with a biphasic SS intravascular tumor of the left inguinal area with femoral vessels involvement. Ten cases of intravascular SS have been reported in the literature and contain little information regarding the proper management of a local metastatic disease. Ours is a rare case of SS with an intravascular tumor occupying the femoral-iliac vein (as seen in metastatic disease) that has been treated as a local disease with a multidisciplinary therapeutic approach. As a result, our patient has been disease-free for two years and, during that time, has achieved an acceptable quality of life. We discuss the pertinent clinical findings of this rare tumor and review the literature of tumor thrombus by SS. We also present the multidisciplinary therapeutic approach realized and the history of this disease.

9.
Electrophoresis ; 36(7-8): 1043-50, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25640071

RESUMO

Olive (Olea europaea L.) pollen is a major health concern in the Mediterranean countries and some olive growing regions in America and Australia. The molecular variability of pollen allergens constitutes a handicap for commercial extract standardization, which is the base of current diagnosis and vaccination procedures. In this paper, we report a time-saving and plant material saving multiplex detection method for the rapid and simultaneous analysis of Ole e 1, Ole e 2, and Ole e 5 allergen polymorphism on a single blot. This method combines high-resolution 2DE techniques with high-sensitive fluorescence-based detection methods. Using this strategy, we were capable to identify a higher number of allergen forms compared with classical 1D approach. The use of fluorescent probes and the increased resolution of 2D blots avoided overlapping effects, and allow estimating the amount of individual allergen forms. In addition, the pattern and identity of the IgE-reactive proteins of either a population or individual patients allergic to olive pollen was also effortlessly determined in a single additional step. This flexible method might be extended to a higher number of olive allergens and cultivars, and is also applicable to other allergogenic plant species and sources.


Assuntos
Alérgenos/análise , Western Blotting/métodos , Pólen , Rinite Alérgica Sazonal/imunologia , Antígenos de Plantas/análise , Eletroforese em Gel Bidimensional/métodos , Fluorescência , Corantes Fluorescentes , Humanos , Imunoglobulina E/imunologia , Proteínas de Plantas/análise , Pólen/efeitos adversos , Pólen/imunologia
10.
J Contemp Brachytherapy ; 6(2): 167-72, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25097557

RESUMO

PURPOSE: Radiotherapy (RT) has played a significant role in treating non melanoma skin cancer (NMSC). High-dose-rate brachytherapy (HDR-BT) approaches have a paramount relevance due to their adaptability, patient protection, and variable dose fractionation schedules. Several innovative applicators have been introduced to the brachytherapy community. The Valencia applicator is a new superficial device that improves the dose distribution compared with the Leipzig applicator. The purpose of this work is to assess the tumor control, cosmesis, and toxicity in patients with NMSC treated with the Valencia applicator and a new regimen of hypofractionation. MATERIAL AND METHODS: From January 2008 to March 2010, 32 patients with 45 NMSC lesions were treated with the Valencia applicator in the Hospital La Fe. The gross tumor volume was visually assessed, but the tumor depth was evaluated using ultrasound imaging. All lesions for the selected cases were limited to 4 mm depth. The prescription dose was 42 Gy in 6 or 7 fractions (biologically effective dose [BED] ≈ 70 Gy), delivered twice a week. RESULTS: Ninety-eight percent of the lesions were locally controlled at 47 months from treatment. Ninety-three percent of patients were out at least 36 months from treatment. The treatment was well tolerated in all cases. The highest skin toxicity was grade 1 RTOG/EORTC, having resolved with topical treatment at 4 weeks in all but one case which required 2 months. There were no grade 2 or higher late adverse events. CONCLUSIONS: In patients with superficial basal cell carcinoma lesions less than 25 mm in maximum diameter, HDRBT treatment with the Valencia applicator using a hypofractionated regimen provides excellent results, for both cosmetic and local control at a minimum of 3 years follow-up. Moreover, the shorter hypofractionated regimen facilitates compliance, which is very relevant for the elderly patients in our series. Valencia applicators offer a simple, safe, quick, and attractive nonsurgical treatment option.

11.
Radiat Oncol ; 9: 102, 2014 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-24885287

RESUMO

PURPOSE: To evaluate efficacy and toxicity after salvage brachytherapy (BT) in prostate local recurrence after radiation therapy. METHODS AND MATERIALS: Between 1993 and 2007, we retrospectively analyzed 56 consecutively patients (pts) undergoing salvage brachytherapy. After local biopsy-proven recurrence, pts received 145 Gy LDR-BT (37 pts, 66%) or HDR-BT (19 pts, 34%) in different dose levels according to biological equivalent doses (BED(2 Gy)). By the time of salvage BT, only 15 pts (27%) received ADT. Univariate and multivariate analyses were performed to identify predictors of biochemical control and toxicities. Acute and late genitourinary (GU) and gastrointestinal (GI) toxicities were graded using Common Terminology Criteria for Adverse Events (CTCv3.0). RESULTS: Median follow-up after salvage BT was 48 months. The 5-year FFbF was 77%. HDR and LDR late grade 3 GU toxicities were observed in 21% and 24%. Late grade 3 GI toxicities were observed in 2% (HDR) and 2.7% (LDR). On univariate analysis, pre-salvage prostate-specific antigen (PSA) > 10 ng/ml (p = 0.004), interval to relapse after initial treatment < 24 months (p = 0.004) and salvage HDR-BT doses BED(2 Gy) level < 227 Gy (p = 0.012) were significant in predicting biochemical failure. On Cox multivariate analysis, pre-salvage PSA, and time to relapse were significant in predicting biochemical failure. HDR-BT BED(2 Gy) (α/ß 1.5 Gy) levels ≥ 227 (p = 0.013), and ADT (p = 0.049) were significant in predicting grade ≥ 2 urinary toxicity. CONCLUSIONS: Prostate BT is an effective salvage modality in some selected prostate local recurrence patients after radiation therapy. Even, we provide some potential predictors of biochemical control and toxicity for prostate salvage BT, further investigation is recommended.


Assuntos
Braquiterapia , Radioisótopos do Iodo/uso terapêutico , Recidiva Local de Neoplasia/radioterapia , Neoplasias/tratamento farmacológico , Neoplasias da Próstata/radioterapia , Lesões por Radiação/diagnóstico , Terapia de Salvação , Idoso , Idoso de 80 Anos ou mais , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/mortalidade , Recidiva Local de Neoplasia/patologia , Estadiamento de Neoplasias , Neoplasias/patologia , Prognóstico , Neoplasias da Próstata/mortalidade , Neoplasias da Próstata/patologia , Estudos Retrospectivos , Taxa de Sobrevida
12.
Clin Transl Oncol ; 14(6): 471-80, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22634537

RESUMO

INTRODUCTION: Neoadjuvant 5-FU-based chemoradiotherapy in resectable rectal cancer (RC) is a standard of treatment. The use of oral fluoropyrimidines and new agents such as oxaliplatin may improve efficacy and tolerance. MATERIAL AND METHODS: Between 1999 and 2009, 126 RC patients with T3-T4 and/or N+ disease were given three successive protocols: UFT (32), UFT-oxaliplatin (75) and capecitabine-oxaliplatin (19), alongside 45 Gy of radiotherapy; with surgery 4-6 weeks after. Adjuvant treatment was given in all patients. The primary objective was pathologic complete response (pCR). RESULTS: Preoperative therapy was well tolerated, with no toxic deaths and a 15% grade 3-4 toxicity rate. Eighty-five percent of patients received the full chemotherapy dose, 56% had an abdominoperineal resection, 6% reinterventions and 57% received the full adjuvant chemotherapy planned. The pCR rate was 13%. The downstaging rate was 80%; 8% had progression of disease. The relapse rate was 20%, with local relapse in 6%. By 5 years of followup, 92% of relapses had occurred. Median follow-up was 73 months, 5- and 10-year disease-free survival rates were 75% and 50%, and 5- and 10-year overall survival rates were 79% and 66% respectively. There was no benefit from the use of oxaliplatin regarding survival or pCR rates. Older patients had worse long-term outcomes. CONCLUSIONS: Neoadjuvant chemoradiotherapy with oral fluoropyrimidines and oxaliplatin is feasible and well tolerated. The risk of early progression is low. However, there was no added benefit with the use of oxaliplatin. There were no relapses in patients with pCR. The role of adjuvant chemotherapy is unclear.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias Retais/terapia , Adulto , Idoso , Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Quimiorradioterapia , Vias de Administração de Medicamentos , Feminino , Fluoruracila/administração & dosagem , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Terapia Neoadjuvante , Compostos Organoplatínicos/administração & dosagem , Oxaliplatina , Neoplasias Retais/patologia , Neoplasias Retais/cirurgia
13.
J Appl Clin Med Phys ; 13(2): 3667, 2012 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-22402383

RESUMO

A new titanized breast mesh, TiLOOP Bra, is currently available for implantation in patients who require radiotherapy. The purpose of this work is to study the dosimetric effect of the presence of a TiLOOP Bra mesh on breast radiation treatment and radiographic imaging. The dosimetric effects have been measured for three X-ray energies: 1.25 MeV, 6 MV and 18 MV, using radiochromic films placed at three different depths. These depths are representative of mesh location in breast during the radiotherapy treatment and hence, are of interest in this study. In order to assess the disturbance in a radiographic image, different computed tomographic (CT) studies of the mesh have been performed. The absorbed dose differences with and without the mesh are less than 1%. No metallic artifacts have been observed in radiographic images associated with the mesh, nor significant disturbances in Hounsfield Units. The TiLOOP Bra mesh does not disturb the dosimetry of a typical radiotherapy treatment and its influence in the quality of the CT scan required for planning is negligible.


Assuntos
Implantes de Mama , Neoplasias da Mama/diagnóstico por imagem , Neoplasias da Mama/radioterapia , Interpretação de Imagem Radiográfica Assistida por Computador/métodos , Planejamento da Radioterapia Assistida por Computador , Telas Cirúrgicas , Tomografia Computadorizada por Raios X , Neoplasias da Mama/patologia , Feminino , Humanos , Imagens de Fantasmas , Dosagem Radioterapêutica
14.
J Contemp Brachytherapy ; 3(3): 121-4, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23346120

RESUMO

PURPOSE: The common use of nomograms in Low Dose Rate (LDR) permanent prostate brachytherapy (BT) allows to estimate the number of seeds required for an implant. Independent dosimetry verification is recommended for each clinical dosimetry in BT. Also, nomograms can be useful for dose calculation quality assurance and they could be adapted to High Dose Rate (HDR). This work sets nomograms for LDR and HDR prostate-BT implants, which are applied to three different institutions that use different implant techniques. MATERIAL AND METHODS: Patients treated throughout 2010 till April 2011 were considered for this study. This example was chosen to be the representative of the latest implant techniques and to ensure consistency in the planning. A sufficient number of cases for both BT modalities, prescription dose and different work methodology (depending on the institution) were taken into account. The specific nomograms were built using the correlation between the prostate volume and some characteristic parameters of each BT modality, such as the source Air Kerma Strength, number of implanted seeds in LDR or total radiation time in HDR. RESULTS: For each institution and BT modality, nomograms normalized to the prescribed dose were obtained and fitted to a linear function. The parameters of the adjustment show a good agreement between data and the fitting. It should be noted that for each institution these linear function parameters are different, indicating that each centre should construct its own nomograms. CONCLUSIONS: Nomograms for LDR and HDR prostate brachytherapy are simple quality assurance tools, specific for each institution. Nevertheless, their use should be complementary to the necessary independent verification.

15.
Clin Transl Oncol ; 12(3): 181-7, 2010 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-20231123

RESUMO

Gynaecologic brachytherapy (BT) is a fundamental part of the treatment of gynaecologic carcinomas, especially if it is not possible to perform surgery. Traditionally, low-dose-rate BT and planning by orthogonal X-rays have been used. Nowadays, high-dose-rate BT is available in most centres, enabling it to enhance the dose optimisation, radiation protection and comfort of patients. Technical advantages in image and dosimetry have enabled the switch to CT and MRI as a means to define the tumour and the organs at risk, and to perform realistic anatomical-based planning. However a general consensus about the way the dose should be prescribed has not yet been reached. Some centres still use the Manchester points A as the reference to specify the dose. It was imperative to work towards a consensus and for this reason the VII Consensus Meeting of the Radiation Oncology Spanish Society (SEOR) Brachytherapy Group was organised. We agreed that some imaging system, CT or MRI, rather than the traditional system with orthogonal X-rays, should always be used for treatment planning. The dose should be prescribed by volume instead of points. And the given dose should be reported by adding external beam radiotherapy dose and BT dose as EQD2 (isoeffective dose). Caution is also recommended in changing the mode of planning and prescription, taking into account previous experience with points A.


Assuntos
Braquiterapia/métodos , Neoplasias dos Genitais Femininos/radioterapia , Imageamento Tridimensional/métodos , Planejamento da Radioterapia Assistida por Computador/métodos , Feminino , Humanos , Imageamento por Ressonância Magnética , Radiometria/métodos , Sociedades Médicas , Espanha , Tomografia Computadorizada por Raios X
16.
Clin Transl Oncol ; 11(12): 835-41, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-20045790

RESUMO

INTRODUCTION: Neoadjuvant chemoradiotherapy before surgery is an option in the treatment of locally advanced resectable oesophageal cancer (EC). However toxicity is substantial and the improvement in overall survival (OS) with this approach is controversial. METHODS: This was a prospective, single-centre study of neoadjuvant chemotherapy and concomitant chemoradiotherapy with CDDP and 5-FU and 50.4 Gy of external radiotherapy before possible radical surgery in patients with locally advanced resectable EC. If surgery was not possible, a second-phase radiotherapy boost of 10 Gy and one cycle of modified dose chemotherapy were used. RESULTS: Seventy-three patients included between 1998 and 2007: 96% males, median age 61, 83% squamous cell carcinomas, 23% lower third tumours, 36% stage II and 54% stage III and 47% local lymph node involvement. Eighty-six percent completed the combined protocol. Main grade 3-4 toxicities: mucositis (19%) and infections (8%); 4 toxic deaths. Clinical response rates: complete response 54%, partial response 27%, stable disease 8%. Twenty-five patients proceeded to surgery, with radical resection in 24. Pathological response rate: complete response 32%, partial response 52%, progression 16%. There were 7 postoperative deaths and 16 of 34 patients that did not have surgery received the second-phase RT boost. Survival analysis: Median follow-up of 64 months (range 6-134 months). Median OS of 10.33 months. 2-year and 5-year OS of 22 and 16%. The only significant prognostic factor in OS is the clinical complete response rate: 13.9 vs. 7.7 months (p=0.0049). CONCLUSIONS: Our protocol offers a high rate of clinical activity although it is relatively toxic and seems to increase the postoperative mortality, which would blunt any small improvement in survival. The achievement of a complete response is a powerful prognostic factor.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Carcinoma de Células Escamosas/tratamento farmacológico , Carcinoma de Células Escamosas/radioterapia , Carcinoma de Células Escamosas/cirurgia , Neoplasias Esofágicas/tratamento farmacológico , Neoplasias Esofágicas/radioterapia , Neoplasias Esofágicas/cirurgia , Adenocarcinoma/tratamento farmacológico , Adenocarcinoma/mortalidade , Adenocarcinoma/radioterapia , Adenocarcinoma/cirurgia , Adulto , Idoso , Idoso de 80 Anos ou mais , Algoritmos , Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Carcinoma de Células Escamosas/mortalidade , Terapia Combinada , Progressão da Doença , Esquema de Medicação , Neoplasias Esofágicas/mortalidade , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Terapia Neoadjuvante , Análise de Sobrevida , Fatores de Tempo
17.
Radiother Oncol ; 91(2): 181-6, 2009 May.
Artigo em Inglês | MEDLINE | ID: mdl-18947893

RESUMO

PURPOSE: According to the GYN GEC-ESTRO Recommendations, MRI is needed with the modality of T2 weighted. CT-MR compatible tandem plus colpostats (T/C) (Nucletron) is widely used in cervical brachytherapy. The major challenge of MRI is the lack of dummy catheters. Therefore, an additional imaging modality is usually required. One disadvantage of sliced-based reconstruction is that resolution in longitudinal directions can be affected by the slice thickness. The aim of this study is to present a modified T/C applicator in which the catheter visibility is significantly improved. METHODS AND MATERIALS: A modification to the existing T/C applicator has been made available, increasing the catheter entrance diameter. It allows a greater dummy catheter diameter, and consequently it can be filled with more material per unit length. Visibility was studied with different materials. RESULTS: The catheter filled with saline water plus iodine compound was clearly seen in both axial and longitudinal acquisitions. To avoid uncertainties introduced by the slice thickness, a simple procedure is presented using longitudinal acquisitions. CONCLUSIONS: The modified applicator plus catheter allows a powerful signal in T2 weighted MRI, using a very simple and accessible material. Also, a method is proposed to solve the problem of the uncertainty derived from slice thickness using few longitudinal acquisitions.


Assuntos
Braquiterapia/métodos , Neoplasias dos Genitais Femininos/radioterapia , Imageamento por Ressonância Magnética/métodos , Planejamento da Radioterapia Assistida por Computador , Braquiterapia/instrumentação , Cateterismo , Feminino , Humanos , Dosagem Radioterapêutica
18.
J Clin Oncol ; 22(15): 3016-22, 2004 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-15210740

RESUMO

PURPOSE: To assess tolerance and efficacy of preoperative treatment with uracil/tegafur and radiotherapy (RT) followed by surgery and postoperative flurouracil (FU)/leucovorin (LV) in patients with rectal cancer. PATIENTS AND METHODS: Patients (n = 94) with potentially resectable tumors, ultrasound at stages T2N+ (n = 4), T3 (n = 77), T4 (n = 13) were treated with UFT (400 mg/m2/d, 5 days a week for 5 weeks) and concomitant RT to the pelvis (45 Gy; 1.8 Gy/d over 5 weeks). Patients underwent surgery 5 to 6 weeks later followed by four cycles of FU/LV. Primary end points included downstaging, pathologic responses, and sphincter-preserving surgery. Secondary end points were recurrence-free survival and overall survival. RESULTS: All patients received the full RT dose. Fifteen patients (16%) needed UFT dose reduction. Preoperative G3+ toxicities included diarrhea (14%), leukopenia (1%), thrombocytopenia (1%), and nausea (4%). The downstaging rate was 54%, pathologic complete response (pCR) was 9% and, in an additional 23%, there were only residual microscopic foci. When cellular viability criteria were taken into account, the pCR was 15%. From 43 patients with abdominoperineal resection indication, 11 (25%) had sphincter-preserving surgery performed. Postoperative scheduled chemotherapy dose was not administered to 24% of patients because of G3+ toxicity (diarrhea, 8%; mucositis, 9%; and leukopenia, 7%). Patients with downstaging had significantly higher survival and recurrence-free survival rates than those without. At 3 years, actuarial patterns of failure were pelvic, 5% and distant, 11%. OS was 75%. CONCLUSION: UFT combined with RT is safe and effective. In resectable rectal cancer, if preoperative treatment is considered, this approach can be an option.


Assuntos
Adenocarcinoma/terapia , Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Neoplasias Retais/terapia , Tegafur/administração & dosagem , Uracila/administração & dosagem , Adenocarcinoma/mortalidade , Adulto , Idoso , Idoso de 80 Anos ou mais , Terapia Combinada , Intervalo Livre de Doença , Feminino , Seguimentos , Humanos , Leucovorina/administração & dosagem , Masculino , Pessoa de Meia-Idade , Período Pós-Operatório , Cuidados Pré-Operatórios , Neoplasias Retais/mortalidade , Neoplasias Retais/radioterapia , Neoplasias Retais/cirurgia
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