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1.
NPJ Precis Oncol ; 8(1): 93, 2024 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-38653773

RESUMO

Anal squamous cell carcinoma (ASCC) is associated with immunosuppression and infection with human papillomavirus (HPV). Response to standard chemoradiotherapy (CRT) varies considerably. A comprehensive molecular characterization of CRT resistance is lacking, and little is known about the interplay between tumor immune contexture, host immunity, and immunosuppressive and/or immune activating effects of CRT. Patients with localized ASCC, treated with CRT at three different sites of the German Cancer Consortium (DKTK) were included. Patient cohorts for molecular analysis included baseline formalin fixed paraffin embedded biopsies for immunohistochemistry (n = 130), baseline RNA sequencing (n = 98), peripheral blood immune profiling (n = 47), and serum cytokine measurement (n = 35). Gene set enrichment analysis showed that pathways for IFNγ, IFNα, inflammatory response, TNFα signaling via NF-κB, and EMT were significantly enriched in poor responders (all p < 0.001). Expression of interferon-induced transmembrane protein 1 (IFITM1), both on mRNA and protein levels, was associated with reduced Freedom from locoregional failure (FFLF, p = 0.037) and freedom from distant metastasis (FFDM, p = 0.014). An increase of PD-L1 expression on CD4+ T-cells (p < 0.001) and an increase in HLA-DR expression on T-cells (p < 0.001) was observed in the peripheral blood after CRT. Elevated levels of regulatory T-cells and CXCL2 were associated with reduced FFLF (p = 0.0044 and p = 0.004, respectively). Inflammatory pathways in tissue in line with elevated levels of regulatory T-cells and CXCL2 in peripheral blood are associated with resistance to CRT. To counteract this resistance mechanism, the RADIANCE randomized phase-2 trial currently tests the addition of the immune checkpoint inhibitor durvalumab to standard CRT in locally advanced ASCC.

3.
Radiother Oncol ; 167: 233-238, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34999135

RESUMO

BACKGROUND AND PURPOSE: Prognosis after chemoradiotherapy (CRT) for anal squamous cell carcinoma (ASCC) shows marked differences among patients according to TNM subgroups, however individualized risk assessment tools to better stratify patients for treatment (de-) escalation or intensified follow-up are lacking in ASCC. MATERIALS AND METHODS: Patients' data from eight sites of the German Cancer Consortium - Radiation Oncology Group (DKTK-ROG), comprising a total of 605 patients with ASCC, treated with standard definitive CRT with 5-FU/Mitomycin C or Capecitabine/Mitomycin C between 2004-2018, were used to evaluate prognostic factors based on Cox regression models for disease-free survival (DFS). Evaluated variables included age, gender, Karnofsky performance score (KPS), HIV-status, T-category, lymph node status and laboratory parameters. Multivariate cox models were separately constructed for the whole cohort and the subset of patients with early-stage (cT1-2 N0M0) tumors. RESULTS: After a median follow-up of 46 months, 3-year DFS for patients with early-stage ASCC was 84.9%, and 67.1% for patients with locally-advanced disease (HR 2.4, p < 0.001). T-category (HR vs. T1: T2 2.02; T3 2.11; T4 3.03), N-category (HR versus N0: 1.8 for N1-3), age (HR 1.02 per year), and KPS (HR 0.8 per step) were significant predictors for DFS in multivariate analysis in the entire cohort. The model performed with a C-index of 0.68. In cT1-2N0 patients, T-category (HR 2.14), HIV status (HR 2.57), age (1.026 per year), KPS (HR 0.7 per step) and elevated platelets (HR 1.3 per 100/nl) were associated with worse DFS (C-index of 0.7). CONCLUSION: Classical clinicopathologic parameters like T-category, N-category, age and KPS remain to be significant prognostic factors for DFS in patients treated with contemporary CRT for ASCC. HIV and platelets were significantly associated with worse DFS in patients with early stage ASCC.


Assuntos
Neoplasias do Ânus , Carcinoma de Células Escamosas , Quimiorradioterapia , Neoplasias do Ânus/terapia , Carcinoma de Células Escamosas/terapia , Infecções por HIV/tratamento farmacológico , Infecções por HIV/etiologia , Humanos , Mitomicina , Prognóstico , Estudos Retrospectivos
4.
Strahlenther Onkol ; 198(1): 1-11, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34786605

RESUMO

The new Medical Licensing Regulations 2025 (Ärztliche Approbationsordnung, ÄApprO) will soon be passed by the Federal Council (Bundesrat) and will be implemented step by step by the individual faculties in the coming months. The further development of medical studies essentially involves an orientation from fact-based to competence-based learning and focuses on practical, longitudinal and interdisciplinary training. Radiation oncology and radiation therapy are important components of therapeutic oncology and are of great importance for public health, both clinically and epidemiologically, and therefore should be given appropriate attention in medical education. This report is based on a recent survey on the current state of radiation therapy teaching at university hospitals in Germany as well as the contents of the National Competence Based Learning Objectives Catalogue for Medicine 2.0 (Nationaler Kompetenzbasierter Lernzielkatalog Medizin 2.0, NKLM) and the closely related Subject Catalogue (Gegenstandskatalog, GK) of the Institute for Medical and Pharmaceutical Examination Questions (Institut für Medizinische und Pharmazeutische Prüfungsfragen, IMPP). The current recommendations of the German Society for Radiation Oncology (Deutsche Gesellschaft für Radioonkologie, DEGRO) regarding topics, scope and rationale for the establishment of radiation oncology teaching at the respective faculties are also included.


Assuntos
Docentes de Medicina , Radioterapia (Especialidade) , Competência Clínica , Currículo , Alemanha , Humanos , Radioterapia (Especialidade)/educação
5.
Phys Rev E ; 104(4-2): 045210, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34781535

RESUMO

Numerous experiments on laser-driven proton acceleration in the MeV range have been performed with a large variety of laser parameters since its discovery around the year 2000. Both experiments and simulations have revealed that protons are accelerated up to a maximum cut-off energy during this process. Several attempts have been made to find a universal model for laser proton acceleration in the target normal sheath acceleration regime. While these models can qualitatively explain most experimental findings, they can hardly be used as predictive models, for example, for the energy cut-off of accelerated protons, as many of the underlying parameters are often unknown. Here we analyze experiments on laser proton acceleration in which scans of laser and target parameters were performed. We derive empirical scaling laws from these parameter scans and combine them in a scaling law for the proton energy cut-off that incorporates the laser pulse energy, the laser pulse duration, the focal spot radius, and the target thickness. Using these scaling laws, we give examples for predicting the proton energy cut-off and conversion efficiency for state-of-the-art laser systems.

6.
Br J Surg ; 108(10): 1251-1258, 2021 10 23.
Artigo em Inglês | MEDLINE | ID: mdl-34240110

RESUMO

BACKGROUND: The purpose of this study was to investigate the prevalence of ypN+ status according to ypT category in patients with locally advanced rectal cancer treated with chemoradiotherapy and total mesorectal excision, and to assess the impact of ypN+ on disease recurrence and survival by pooled analysis of individual-patient data. METHODS: Individual-patient data from 10 studies of chemoradiotherapy for rectal cancer were included. Pooled rates of ypN+ disease were calculated with 95 per cent confidence interval for each ypT category. Kaplan-Meier and Cox regression analyses were undertaken to assess influence of ypN status on 5-year disease-free survival (DFS) and overall survival (OS). RESULTS: Data on 1898 patients were included in the study. Median follow-up was 50 (range 0-219) months. The pooled rate of ypN+ disease was 7 per cent for ypT0, 12 per cent for ypT1, 17 per cent for ypT2, 40 per cent for ypT3, and 46 per cent for ypT4 tumours. Patients with ypN+ disease had lower 5-year DFS and OS (46.2 and 63.4 per cent respectively) than patients with ypN0 tumours (74.5 and 83.2 per cent) (P < 0.001). Cox regression analyses showed ypN+ status to be an independent predictor of recurrence and death. CONCLUSION: Risk of nodal metastases (ypN+) after chemoradiotherapy increases with advancing ypT category and needs to be considered if an organ-preserving strategy is contemplated.


When patients are diagnosed with rectal cancer and the tumour grows beyond the rectal wall there is a high risk that the tumour has spread to nearby lymph nodes. This study showed that this relationship between tumour invasion depth and lymph node involvement is similar after treatment with (chemo)radiotherapy. Patients who have tumour cells remaining in the lymph nodes after (chemo) radiotherapy have a worse prognosis than patients who do not have cancer cells remaining in the lymph nodes. When an organ-preserving treatment is considered as an alternative therapy, this should be kept in mind during patient counselling.


Assuntos
Linfonodos/patologia , Metástase Linfática , Neoplasias Retais/patologia , Neoplasias Retais/terapia , Idoso , Idoso de 80 Anos ou mais , Quimiorradioterapia Adjuvante , Feminino , Humanos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Invasividade Neoplásica , Recidiva Local de Neoplasia , Protectomia , Neoplasias Retais/cirurgia , Análise de Regressão
8.
Radiother Oncol ; 154: 154-160, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-32966845

RESUMO

PURPOSE: Optimal timing of surgery after neoadjuvant chemoradiotherapy (Nad-CRT) is still controversial in locally advanced rectal cancer (LARC). The primary goal of this study was to determine the best surgical interval (SI) to achieve the highest rate of pathological complete response (pCR) and secondly to evaluate the effect on survival outcomes according to the SI. PATIENTS AND METHODS: Patients data were extracted from the international randomized trials: Accord12/0405, EORTC22921, FFCD9203, CAO/ARO/AIO-94, CAO-ARO-AIO-04, INTERACT and TROG01.04. Inclusion criteria were: age≥ 18, cT3-T4 and cN0-2, no clinical evidence of distant metastasis at diagnosis, Nad-CRT followed by surgery. Pearson's Chi-squared test with Yates' continuity correction for categorical variables, the Mann-Whitney test for continuous variables, Mann-Kendall test, Kaplan-Meier curves with log-rank test, univariate and multivariate logistic regression model was used for data analysis. RESULTS: 3085 patients met the inclusion criteria. Overall, the pCR rate was 14% at a median SI of 6 weeks (range 1-31). The cumulative pCR rate increased significantly when SI lengthened, with 95% of pCR events within 10 weeks from Nad-CRT. At univariate and multivariate logistic regression analysis, lengthening of SI (p< 0.01), radiotherapy dose (p< 0.01), and the addition of oxaliplatin to Nad-CRT (p< 0.01) had a favorable impact on pCR. Furthermore, lengthening of SI was not impact on local recurrences, distance metastases, and overall survival. CONCLUSION: This pooled analysis suggests that the best time to achieve pCR in LARC is at 10 weeks, considering that the lengthening of SI is not detrimental concerning survival outcomes.


Assuntos
Recidiva Local de Neoplasia , Neoplasias Retais , Adolescente , Quimiorradioterapia , Humanos , Terapia Neoadjuvante , Recidiva Local de Neoplasia/patologia , Estadiamento de Neoplasias , Ensaios Clínicos Controlados Aleatórios como Assunto , Neoplasias Retais/patologia , Resultado do Tratamento
9.
Radiat Oncol ; 15(1): 262, 2020 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-33172475

RESUMO

The role of radiation therapy in the treatment of (colo)-rectal cancer has changed dramatically over the past decades. Introduced with the aim of reducing the high rates of local recurrences after conventional surgery, major developments in imaging, surgical technique, systemic therapy and radiation delivery have now created a much more complex environment leading to a more personalized approach. Functional aspects including reduction of acute or late treatment-related side effects, sphincter or even organ-preservation and the unsolved problem of still high distant failure rates have become more important while local recurrence rates can be kept low in the vast majority of patients. This review summarizes the actual role of radiation therapy in different subgroups of patients with rectal cancer, including the current standard approach in different subgroups as well as recent developments focusing on neoadjuvant treatment intensification and/or non-operative treatment approaches aiming at organ-preservation.


Assuntos
Quimiorradioterapia , Neoplasias Retais/terapia , Ensaios Clínicos como Assunto , Humanos , Terapia Neoadjuvante
10.
Urologe A ; 59(10): 1237-1245, 2020 Oct.
Artigo em Alemão | MEDLINE | ID: mdl-32617622

RESUMO

BACKGROUND: Men die earlier than women in Germany. Men also have impaired access to cancer screening compared to women. OBJECTIVES: Our Movember campaign 2019 at University Hospital Frankfurt (UKF) aimed at improving health care awareness in the context of prostate cancer checkup. MATERIALS AND METHODS: In November 2019, every male employee of the UKF with a minimum age of 45 yrs (or 40 yrs with a first degree relative with prostate cancer) was offered a free prostate cancer checkup. This checkup contained digital rectal examination (DRE), transrectal ultrasound and PSA (prostata-specific antigen) testing. RESULTS: Overall, 121/840 employees (14.4%) participated in the Movember campaign. A first degree relative with prostate cancer was reported in overall by 14% of the participants (n = 17). At least one prior prostate cancer check up had 33%. A total of 2.5% (n = 3) had one prior negative prostate biopsy. Median age was 54 yrs (interquartile range 50-58). Median PSA level was 0.9 ng/ml and median free-PSA 0.3 ng/ml. A suspicious DRE was found in 5% (n = 6). After stratification according to age (≤ 50 yrs vs. > 50 yrs), participants over 50 yrs had a significantly higher PSA level (1.0 ng/ml vs. 0.7 ng/ml, p < 0.01) and had more frequently at least one prior prostate cancer checkup in the past (42.0 vs. 12.1%, p < 0.01). All suspicious DREs were in the cohort > 50 yrs. Overall, 32.2% (n = 39) had at least a suspicious checkup. A total of 3.3% (n = 4) had suspicious PSA levels. 17.4% (n = 21) of the participants had a suspicious PSA ratio (< 20%) only. During follow-up, 6 prostate biopsies were performed, with the detection of one case of intermediate-risk prostate cancer (Gleason 3 + 4, pT3a, pPn1, pNx, R0). CONCLUSION: Overall, 121 employees participated in our Movember Prostate cancer checkup campaign with measurement of the PSA level. Suspicious results were recorded in 32.2%. One employee was diagnosed and successfully treated with an intermediate-risk prostate cancer.


Assuntos
Detecção Precoce de Câncer , Neoplasias da Próstata , Exame Retal Digital , Alemanha , Humanos , Masculino , Programas de Rastreamento , Pessoa de Meia-Idade , Antígeno Prostático Específico , Neoplasias da Próstata/diagnóstico
12.
Strahlenther Onkol ; 195(5): 369-373, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30937508

RESUMO

Definitive chemoradiotherapy (CRT) is the standard treatment for anal squamous cell carcinoma (ASCC). Data regarding treatment outcome according to TNM classification is scarce. Here, we review data of randomized trials and retrospective cohorts suggesting a poor 3­year disease-free survival (DFS; or progression-free survival, PFS) of approximately 60%, or even lower, in patients with locally advanced T3-4 and/or N+ disease, while patients with T1-2N0 ASCC have 3­year DFS/PFS rates exceeding 80%. These results are in line with our data in a cohort of 210 patients with ASCC treated with definitive 5­fluorouracil/mitomycin C­based CRT to a total dose of 50.4 Gy plus a boost of 3.6-10.8 Gy. The implications of these findings and the current trials testing radiotherapy dose escalation/de-escalation strategies are reported. Finally, we will discuss the strong rationale for testing immune checkpoint blockade (ICB) with CRT in clinical trials to improve results, especially in patients with advanced ASCC.


Assuntos
Neoplasias do Ânus/terapia , Carcinoma de Células Escamosas/terapia , Quimiorradioterapia/métodos , Neoplasias do Ânus/mortalidade , Neoplasias do Ânus/patologia , Carcinoma de Células Escamosas/mortalidade , Carcinoma de Células Escamosas/patologia , Estudos de Coortes , Terapia Combinada , Intervalo Livre de Doença , Fluoruracila/administração & dosagem , Mitomicina/administração & dosagem , Estadiamento de Neoplasias , Intervalo Livre de Progressão , Dosagem Radioterapêutica , Ensaios Clínicos Controlados Aleatórios como Assunto , Estudos Retrospectivos
13.
Ann Oncol ; 29(8): 1793-1799, 2018 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-29873684

RESUMO

Background: The German rectal cancer trial CAO/ARO/AIO-04 has shown a significant benefit in 3-year disease-free survival (DFS) of adding oxaliplatin to a standard preoperative 5-fluorouracil (5-FU)-based chemoradiotherapy (CRT) and adjuvant chemotherapy in patients with locally advanced rectal cancer. The use of oxaliplatin as adjuvant treatment in elderly patients with colon cancer is controversial. We therefore investigated the impact of age on clinical outcome in the CAO/ARO/AIO-04 phase III trial. Patients and methods: We carried out a post hoc analysis of the CAO/ARO/AIO-04 phase III trial evaluating primary and secondary end points according to age. Patient and tumor characteristics, NCI CTC adverse events grades 3-4 (version 3.0), dose intensities as well as survival and recurrence data were analyzed in three specified age groups (<60, 60-70, and ≥70 years). The influence of age as a continuous variable on DFS was modeled using a subpopulation treatment effect pattern plot (STEPP) analysis. Results: A total of 1232 patients were assessable. With the exception of Eastern Cooperative Oncology Group status (P < 0.001), no differences in patient and tumor characteristics were noticed between age groups. Likewise, toxicity pattern, dose intensities of CRT and surgical results were similar in all age groups. After a median follow-up of 50 months, in patients aged <60 years a significant benefit of adding oxaliplatin to 5-FU-based CRT and adjuvant chemotherapy was observed for local (P = 0.013) and systemic recurrences (P = 0.023), DFS (P = 0.011), and even overall survival (OS; P = 0.044). The STEPP analysis revealed improved hazard ratios for DFS in patients aged 40-70 years compared with elderly patients treated with oxaliplatin. Conclusion: The addition of oxaliplatin significantly improved DFS and OS in younger patients aged <60 years with advanced rectal cancer. Patients aged ≥70 years had no benefit. Clinical Trials Number: NCT00349076.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Recidiva Local de Neoplasia/epidemiologia , Oxaliplatina/uso terapêutico , Neoplasias Retais/terapia , Fatores Etários , Idoso , Quimiorradioterapia/efeitos adversos , Quimiorradioterapia/métodos , Quimioterapia Adjuvante/efeitos adversos , Quimioterapia Adjuvante/métodos , Intervalo Livre de Doença , Feminino , Fluoruracila/uso terapêutico , Humanos , Masculino , Pessoa de Meia-Idade , Terapia Neoadjuvante/métodos , Recidiva Local de Neoplasia/parasitologia , Recidiva Local de Neoplasia/prevenção & controle , Protectomia , Neoplasias Retais/mortalidade , Neoplasias Retais/patologia
15.
Br J Surg ; 105(11): 1510-1518, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-29846017

RESUMO

BACKGROUND: The influence of postoperative complications on survival in patients with locally advanced rectal cancer undergoing combined modality treatment is debatable. This study evaluated the impact of surgical complications on oncological outcomes in patients with locally advanced rectal cancer treated within the randomized CAO/ARO/AIO-94 (Working Group of Surgical Oncology/Working Group of Radiation Oncology/Working Group of Medical Oncology of the Germany Cancer Society) trial. METHODS: Patients were assigned randomly to either preoperative chemoradiotherapy (CRT) followed by total mesorectal excision (TME) or postoperative CRT between 1995 and 2002. Anastomotic leakage and wound healing disorders were evaluated prospectively, and their associations with overall survival, and distant metastasis and local recurrence rates after a long-term follow-up of more than 10 years were determined. Medical complications (such as cardiopulmonary events) were not analysed in this study. RESULTS: A total of 799 patients were included in the analysis. Patients who had anterior or intersphincteric resection had better 10-year overall survival than those treated with abdominoperineal resection (63·1 versus 51·3 per cent; P < 0·001). Anastomotic leakage was associated with worse 10-year overall survival (51 versus 65·2 per cent; P = 0·020). Overall survival was reduced in patients with impaired wound healing (45·7 versus 62·2 per cent; P = 0·009). At 10 years after treatment, patients developing any surgical complication (anastomotic leakage and/or wound healing disorder) had impaired overall survival (46·6 versus 63·8 per cent; P < 0·001), a lower distant metastasis-free survival rate (63·2 versus 72·0 per cent; P = 0·030) and more local recurrences (15·5 versus 6·4 per cent; P < 0·001). In a multivariable Cox regression model, lymph node metastases (P < 0·001) and surgical complications (P = 0·008) were the only independent predictors of reduced overall survival. CONCLUSION: Surgical complications were associated with adverse oncological outcomes in this trial.


Assuntos
Colectomia/efeitos adversos , Estadiamento de Neoplasias , Complicações Pós-Operatórias/epidemiologia , Neoplasias Retais/terapia , Adulto , Idoso , Terapia Combinada , Intervalo Livre de Doença , Feminino , Seguimentos , Alemanha/epidemiologia , Humanos , Masculino , Pessoa de Meia-Idade , Morbidade/tendências , Prognóstico , Neoplasias Retais/diagnóstico , Neoplasias Retais/mortalidade , Estudos Retrospectivos , Taxa de Sobrevida/tendências , Fatores de Tempo
16.
Ann Oncol ; 29(7): 1521-1527, 2018 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-29718095

RESUMO

Background: Surrogate end points in rectal cancer after preoperative chemoradiation are lacking as their statistical validation poses major challenges, including confirmation based on large phase III trials. We examined the prognostic role and individual-level surrogacy of neoadjuvant rectal (NAR) score that incorporates weighted cT, ypT and ypN categories for disease-free survival (DFS) in 1191 patients with rectal carcinoma treated within the CAO/ARO/AIO-04 phase III trial. Patients and methods: Cox regression models adjusted for treatment arm, resection status, and NAR score were used in multivariable analysis. The four Prentice criteria (PC1-4) were used to assess individual-level surrogacy of NAR for DFS. Results: After a median follow-up of 50 months, the addition of oxaliplatin to fluorouracil-based chemoradiotherapy (CRT) significantly improved 3-year DFS [75.9% (95% confidence interval [CI] 72.30% to 79.50%) versus 71.3% (95% CI 67.60% to 74.90%); P = 0.034; PC 1) and resulted in a shift toward lower NAR groups (P = 0.034, PC 2) compared with fluorouracil-only CRT. The 3-year DFS was 91.7% (95% CI 88.2% to 95.2%), 81.8% (95% CI 78.4% to 85.1%), and 58.1% (95% CI 52.4% to 63.9%) for low, intermediate, and high NAR score, respectively (P < 0.001; PC 3). NAR score remained an independent prognostic factor for DFS [low versus high NAR: hazard ratio (HR) 4.670; 95% CI 3.106-7.020; P < 0.001; low versus intermediate NAR: HR 1.971; 95% CI 1.303-2.98; P = 0.001] in multivariable analysis. Notwithstanding the inherent methodological difficulty in interpretation of PC 4 to establish surrogacy, the treatment effect on DFS was captured by NAR, supporting satisfaction of individual-level PC 4. Conclusion: Our study validates the prognostic role and individual-level surrogacy of NAR score for DFS within a large randomized phase III trial. NAR score could help oncologists to speed up response-adapted therapeutic decision, and further large phase III trial data sets should aim to confirm trial-level surrogacy.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Quimiorradioterapia Adjuvante/mortalidade , Terapia Neoadjuvante/mortalidade , Neoplasias Retais/mortalidade , Neoplasias Retais/patologia , Idoso , Biomarcadores , Feminino , Fluoruracila/administração & dosagem , Seguimentos , Humanos , Masculino , Oxaliplatina/administração & dosagem , Prognóstico , Modelos de Riscos Proporcionais , Neoplasias Retais/terapia , Taxa de Sobrevida
17.
Urologe A ; 57(6): 679-685, 2018 Jun.
Artigo em Alemão | MEDLINE | ID: mdl-29651707

RESUMO

BACKGROUND: The standard treatment for muscle-invasive bladder cancer is radical cystectomy with pelvic lymphadenectomy. Primary organ-preservation by means of multimodal therapy, however, can be a viable alternative to radical surgery. OBJECTIVES: The concept and results of multimodal therapy, consisting of initial transurethral resection of the bladder tumor (TUR-B), followed by simultaneous radiochemotherapy (RCT), are presented. MATERIALS AND METHODS: Evaluation of retrospective cohorts and prospective therapy optimization studies on organ-preservation treatment regimens. Comparative meta-analyses comparing cystectomy with multimodal treatment are presented. RESULTS: Complete TUR-B, including bladder mapping and tumor biopsy, should precede simultaneous RCT. Radiosensitization should be cisplatin-based or consist of a combination of 5­fluorouracil and mitomycin C. Complete response rates after TUR-B plus RCT are generated in 60-90% of patients along with 5­year survival rates of 40-75% and preservation of the bladder in approximately 80% of surviving patients. CONCLUSIONS: Multimodal therapy by means of TUR-B followed by simultaneous RCT is a viable alternative to radical cystectomy for patients with muscle-invasive urinary bladder carcinoma. Patients with early tumors (cT2/3N0) are particularly suitable in whom initial TUR-B leads to complete tumor resection (R0).


Assuntos
Carcinoma de Células de Transição/terapia , Quimiorradioterapia/métodos , Cisplatino/administração & dosagem , Cistectomia/métodos , Excisão de Linfonodo , Mitomicina/uso terapêutico , Preservação de Órgãos , Neoplasias da Bexiga Urinária/terapia , Antibióticos Antineoplásicos , Antineoplásicos/administração & dosagem , Biópsia , Carcinoma de Células de Transição/radioterapia , Carcinoma de Células de Transição/cirurgia , Cisplatino/uso terapêutico , Terapia Combinada , Fluoruracila/administração & dosagem , Humanos , Invasividade Neoplásica , Estudos Prospectivos , Estudos Retrospectivos , Resultado do Tratamento , Uretra/cirurgia , Neoplasias da Bexiga Urinária/radioterapia , Neoplasias da Bexiga Urinária/cirurgia
18.
Rev Sci Instrum ; 89(2): 023703, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29495844

RESUMO

We present an extreme ultraviolet (EUV) microscope using a Schwarzschild objective which is optimized for single-shot sub-micrometer imaging of laser-plasma targets. The microscope has been designed and constructed for imaging the scattering from an EUV-heated solid-density hydrogen jet. Imaging of a cryogenic hydrogen target was demonstrated using single pulses of the free-electron laser in Hamburg (FLASH) free-electron laser at a wavelength of 13.5 nm. In a single exposure, we observe a hydrogen jet with ice fragments with a spatial resolution in the sub-micrometer range. In situ EUV imaging is expected to enable novel experimental capabilities for warm dense matter studies of micrometer-sized samples in laser-plasma experiments.

20.
Phys Rev Lett ; 118(19): 194801, 2017 May 12.
Artigo em Inglês | MEDLINE | ID: mdl-28548516

RESUMO

We report experimental evidence that multi-MeV protons accelerated in relativistic laser-plasma interactions are modulated by strong filamentary electromagnetic fields. Modulations are observed when a preplasma is developed on the rear side of a µm-scale solid-density hydrogen target. Under such conditions, electromagnetic fields are amplified by the relativistic electron Weibel instability and are maximized at the critical density region of the target. The analysis of the spatial profile of the protons indicates the generation of B>10 MG and E>0.1 MV/µm fields with a µm-scale wavelength. These results are in good agreement with three-dimensional particle-in-cell simulations and analytical estimates, which further confirm that this process is dominant for different target materials provided that a preplasma is formed on the rear side with scale length ≳0.13λ_{0}sqrt[a_{0}]. These findings impose important constraints on the preplasma levels required for high-quality proton acceleration for multipurpose applications.

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