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1.
J Neurooncol ; 149(3): 437-445, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33040274

RESUMO

PURPOSE: This study was performed to determine the maximum tolerated dose (MTD) or recommended phase 2 dose (RP2D) of the immunomodulatory agent, lenalidomide, when administered daily during 6 weeks of radiation therapy to children with newly diagnosed diffuse intrinsic pontine glioma (DIPG) or high-grade glioma (HGG) PATIENTS & METHODS: Children and young adults < 22 years of age with newly diagnosed disease and no prior chemotherapy or radiation therapy were eligible. Children with HGG were required to have an inoperable or incompletely resected tumor. Eligible patients received standard radiation therapy to a prescription dose of 54-59.4 Gy, with concurrent administration of lenalidomide daily during radiation therapy in a standard 3 + 3 Phase I dose escalation design. Following completion of radiation therapy, patients had a 2-week break followed by maintenance lenalidomide at 116 mg/m2/day × 21 days of a 28-day cycle. RESULTS: Twenty-nine patients (age range 4-19 years) were enrolled; 24 were evaluable for dose finding (DIPG, n = 13; HGG, n = 11). The MTD was not reached at doses of lenalidomide up to 116 mg/m2/day. Exceptional responses were noted in DIPG and malignant glioma (gliomatosis cerebri) notably at higher dose levels and at higher steady state plasma concentrations. The primary toxicity was myelosuppression. CONCLUSION: The RP2D of lenalidomide administered daily during radiation therapy is 116 mg/m2/day. Children with malignant gliomas tolerate much higher doses of lenalidomide during radiation therapy compared to adults. This finding is critical as activity was observed primarily at higher dose levels suggesting a dose response.


Assuntos
Inibidores da Angiogênese/uso terapêutico , Neoplasias do Tronco Encefálico/terapia , Quimiorradioterapia/métodos , Glioma Pontino Intrínseco Difuso/terapia , Lenalidomida/uso terapêutico , Adolescente , Adulto , Inibidores da Angiogênese/farmacocinética , Neoplasias do Tronco Encefálico/patologia , Criança , Pré-Escolar , Glioma Pontino Intrínseco Difuso/patologia , Feminino , Seguimentos , Humanos , Lenalidomida/farmacocinética , Masculino , Dose Máxima Tolerável , Prognóstico , Distribuição Tecidual , Adulto Jovem
2.
Oncology (Williston Park) ; 31(3): 182-8, 2017 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-28299754

RESUMO

Radiation therapy continues to be a key component in the management of pediatric malignancies. Increasing the likelihood of cure while minimizing late treatment toxicity in these young patients remains the primary goal. Within the realm of central nervous system neoplasms, efforts to further improve the efficacy of radiation therapy continue, while balancing risks of damage to uninvolved tissue. Radiation therapy can result in second malignancies, as well as cerebrovascular, neurotoxic, neurocognitive, endocrine, psychosocial, and quality-of-life effects. In this article we describe these acute and late effects and their implications, and we highlight strategies that have emerged to reduce both the volume of tissue that is irradiated and the radiation dose delivered. The feasibility, efficacy, and risks of these newer approaches to radiation therapy continue to be evaluated and monitored; robust outcome data are needed.


Assuntos
Neoplasias do Sistema Nervoso Central/radioterapia , Irradiação Craniana/efeitos adversos , Lesões por Radiação/terapia , Sobreviventes , Adulto , Fatores Etários , Neoplasias do Sistema Nervoso Central/diagnóstico , Criança , Humanos , Qualidade de Vida , Doses de Radiação , Lesões por Radiação/diagnóstico , Lesões por Radiação/etiologia , Lesões por Radiação/psicologia , Fatores de Risco , Sobreviventes/psicologia , Fatores de Tempo , Resultado do Tratamento
3.
Oncology (Williston Park) ; 31(3): 224-6, 228, 2017 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-28299759

RESUMO

Newer approaches in the field of radiation therapy have raised the bar in the treatment of central nervous system (CNS) malignancies, with recognized advances that have aimed to increase the therapeutic index by improving conformality of the radiation dose to the planned target volume. Beyond these advances, the continued evolution of more effective systems for delivery of radiation to the CNS may offer further benefit not only to adults but also to pediatric patients, a cohort of the population that may be more sensitive to the long-term effects of radiation. This article describes several novel irradiation techniques under investigation that hold promise in the pediatric population. These include newer approaches to intensity-modulated radiation therapy; stereotactic radiosurgery and radiation therapy; particle therapy, most notably proton therapy, which may be of particular benefit in enabling young patients to avoid radiation-related adverse effects; and radioimmunotherapy strategies that spare healthy tissue from radiotoxicity by delivering therapy directly to tumor tissue. Although emerging strategies for the delivery of radiation therapy hold promise for improved outcomes in pediatric patients, there must be rigorous long-term evaluation of consequences associated with the various techniques employed, to weigh risks, benefits, and impact on quality of life.


Assuntos
Neoplasias do Sistema Nervoso Central/radioterapia , Irradiação Craniana/métodos , Doses de Radiação , Radioimunoterapia , Radiocirurgia , Planejamento da Radioterapia Assistida por Computador/métodos , Radioterapia de Intensidade Modulada , Sobreviventes , Adulto , Fatores Etários , Neoplasias do Sistema Nervoso Central/diagnóstico , Criança , Irradiação Craniana/efeitos adversos , Humanos , Qualidade de Vida , Lesões por Radiação/etiologia , Lesões por Radiação/prevenção & controle , Radiocirurgia/efeitos adversos , Radioterapia de Intensidade Modulada/efeitos adversos , Fatores de Risco , Fatores de Tempo , Resultado do Tratamento
4.
Blood ; 120(9): 1816-9, 2012 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-22730536

RESUMO

Human T-cell leukemia virus type 1-associated adult T-cell leukemia/lymphoma (ATL) typically has survivals measured in months with chemotherapy. One prior published series (1983-1991) assessed local radiotherapy for ATL. Ten consecutive patients with pathologically confirmed ATL treated with radiotherapy were reviewed. Subtypes included acute (n = 7), smoldering (n = 2), and lymphomatous (n = 1). Patients received an average of 2.5 systemic therapy regimens before radiotherapy. Twenty lesions (cutaneous = 10, nodal = 8, extranodal = 2) were treated to a mean of 35.4 Gy/2-3 Gy (range, 12-60 Gy). At 9.0-month mean follow-up (range, 0.1-42.0 months), all lesions symptomatically and radiographically responded, with in-field complete responses in 40.0% (nodal 37.5% vs. cutaneous 50.0%; P = .62). No patient experienced in-field progression. Nine patients developed new/progressive out-of-field disease. Median survival was 17.0 months (3-year survival, 30.0%). No Radiation Therapy Oncology Group acute grade ≥ 3 or any late toxicity was noted. This report is the first to use modern radiotherapy techniques and finds effective local control across ATL subtypes. Radiotherapy should be considered for symptomatic local progression of ATL.


Assuntos
Infecções por HTLV-I/complicações , Vírus Linfotrópico T Tipo 1 Humano , Leucemia-Linfoma de Células T do Adulto/radioterapia , Radioterapia/métodos , Adulto , Idoso , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Terapia Combinada , Feminino , Infecções por HTLV-I/virologia , Humanos , Leucemia-Linfoma de Células T do Adulto/complicações , Leucemia-Linfoma de Células T do Adulto/tratamento farmacológico , Masculino , Pessoa de Meia-Idade , Mucosite/etiologia , Radioterapia/efeitos adversos , Dosagem Radioterapêutica , Estudos Retrospectivos , Dermatopatias/etiologia , Análise de Sobrevida , Resultado do Tratamento
5.
Radiology ; 268(1): 144-52, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23468576

RESUMO

PURPOSE: To determine whether multiparametric magnetic resonance (MR) imaging can help identify patients with prostate cancer who would most appropriately be candidates for active surveillance (AS) according to current guidelines and to compare the results with those of conventional clinical assessment scoring systems, including the D'Amico, Epstein, and Cancer of the Prostate Risk Assessment (CAPRA) systems, on the basis of findings at prostatectomy. MATERIALS AND METHODS: This institutional review board-approved HIPAA-compliant retrospectively designed study included 133 patients (mean age, 59.3 years) with a mean prostate-specific antigen level of 6.73 ng/mL (median, 4.39 ng/mL) who underwent multiparametric MR imaging at 3.0 T before radical prostatectomy. Informed consent was obtained from all patients. Patients were then retrospectively classified as to whether they would have met AS eligibility criteria or were better served by surgery. AS eligibility criteria for prostatectomy specimens were a dominant tumor smaller than 0.5 mL without Gleason 4 or 5 patterns or extracapsular or seminal vesicle invasion. Conventional clinical assessment scores (the D'Amico, Epstein, and CAPRA scoring systems) were compared with multiparametric MR imaging findings for predicting AS candidates. The level of significance of difference between scoring systems was determined by using the χ(2) test for categoric variables with the level of significance set at P < .05. RESULTS: Among 133 patients, 14 were eligible for AS on the basis of prostatectomy results. The sensitivity, positive predictive value (PPV), and overall accuracy, respectively, were 93%, 25%, and 70% for the D'Amico system, 64%, 45%, and 88% for the Epstein criteria, and 93%, 20%, and 59% for the CAPRA scoring system for predicting AS candidates (P < .005 for all, χ(2) test), while multiparametric MR imaging had a sensitivity of 93%, a PPV of 57%, and an overall accuracy of 92% (P < .005). CONCLUSION: Multiparametric MR imaging provides useful additional information to existing clinicopathologic scoring systems of prostate cancer and improves the assignment of treatment (eg, AS or active treatment).


Assuntos
Imageamento por Ressonância Magnética/métodos , Neoplasias da Próstata/patologia , Adulto , Idoso , Biópsia , Distribuição de Qui-Quadrado , Meios de Contraste , Gadolínio DTPA , Humanos , Masculino , Pessoa de Meia-Idade , Vigilância da População , Valor Preditivo dos Testes , Antígeno Prostático Específico/sangue , Estudos Retrospectivos , Sensibilidade e Especificidade
6.
Curr Opin Oncol ; 24(3): 243-50, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22450149

RESUMO

PURPOSE OF REVIEW: This article reviews recent developments in the use of active surveillance for localized prostate cancer. RECENT FINDINGS: The treatment of localized prostate cancer continues to be a major challenge for urologic oncologists. Screening with prostate-specific antigen has resulted in increased numbers of low-risk prostate cancers being detected. Aggressive whole-gland therapy with surgery, or radiation therapy is associated with potentially life-altering treatment-related side effects such as urinary incontinence, bowel toxicity and erectile dysfunction. The goal of active surveillance is to avoid or delay the adverse events associated with prostate cancer therapy while still allowing for curative intervention in the future, if needed. SUMMARY: Active surveillance is a reasonable treatment option for many men with low-risk, and some men with intermediate-risk, prostate cancer. Additional research is needed to determine the optimal active surveillance inclusion criteria, monitoring schedule, and treatment triggers. It is hoped that advances in prostate imaging, biomarkers, and focal therapy will foster greater use of active surveillance in appropriately selected men to optimize quality-of-life without compromising cancer outcomes.


Assuntos
Vigilância da População , Antígeno Prostático Específico/sangue , Neoplasias da Próstata/diagnóstico , Neoplasias da Próstata/terapia , Qualidade de Vida , Conduta Expectante , Biomarcadores Tumorais/sangue , Diagnóstico Precoce , Disfunção Erétil/etiologia , Humanos , Masculino , Seleção de Pacientes , Prostatectomia/efeitos adversos , Neoplasias da Próstata/imunologia , Neoplasias da Próstata/radioterapia , Neoplasias da Próstata/cirurgia
7.
Lancet Reg Health Am ; 13: 100289, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35692288

RESUMO

Health inequities and decreasing median American lifespan, potentiated by the worldwide COVID 19 crisis, have taken centre stage in the public consciousness. Specifically, for this discourse, rural radiation oncology challenges external to the pandemic and unique to the rural American radiation oncology care delivery result from a confluence of the following: a) increased incidence of cancer in the United States;1 b) recent legislative emphasis on rural healthcare equity initiatives;2 c) pandemic-associated delays in cancer screening, diagnosis, and treatment3 , 4 with resultant presentation of advanced oncologic stages; d) social spotlight on healthcare equity and inclusion for disenfranchised populations.5We will attempt to delineate these issues and propose widely applicable common-sense solutions. We will review what has transpired at the University of Kentucky over the last two decades, specifically at radiation oncology centre in Morehead, a clinic in eastern Kentucky in the Appalachian foothills. While much more work remains ahead, this clinic has successfully applied many of the initiatives discussed. Funding: No relevant funding of any research was involved in the preparation of data or the manuscript.

8.
Case Rep Oncol ; 14(1): 17-23, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-38352276

RESUMO

Aneurysmal fibrous histiocytoma (AFH) is a rare variant of cutaneous fibrous histiocytoma, with low malignant potential and infrequent metastatic progression. We present the case of a 19-year-old female with a large AFH of the neck metastatic to soft tissue and treated with radiation therapy and molecularly targeted therapy. To our knowledge, this is the first report describing either radiation therapy and palliation or the use of targeted therapy in this uncommon malignancy and can provide insight into future therapeutic strategies.

9.
J Appl Clin Med Phys ; 12(1): 3306, 2010 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-21330976

RESUMO

The purpose was to evaluate and correct the co-registration of diagnostic PET/CT and MRI/MRI images for stereotactic radiosurgery (SRS) using 3D volumetric image registration (3DVIR). The 3DVIR utilizes the homogeneity of color distribution over a volumetric anatomical landmark as the registration criterion with submillimeter accuracy. Fifty-three PET/CT and MRI (T1, T2 and FLAIR) image sets of patients with brain lesions were acquired sequentially from a hybrid PET/CT or an MRI scanner with common diagnostic head holding devices. Twenty-five sets of head 18F-FDG-PET/CT images were scanned over a 10-minute interval and 14 whole-body sets were scanned over a 30-minute interval. Fourteen sets of MRI images were acquired, and each 3-modal image set (T1, T2 and FLAIR) was scanned in sequence at time 0, ~5 and ~20 minutes. The misalignments in these "co-registered" images were evaluated and corrected using the 3DVIR. Using the head immobilization devices commonly found in diagnostic PET/CT and MRI/MRI imaging, 80%-100% of these "co-registered" images were identified as misaligned. For PET/CT, the magnitude of misalignment was 0.4° ± 0.5° and 0.7 ± 0.4 mm for 10-minute scans, and 0.8° ± 1.2° and 2.7 ± 1.7 mm for 30-minute scans. For MRI/MRI, the magnitude was 0.2° ± 0.4° and 0.3 ± 0.2 mm for 5-minute scan intervals, and 1.1° ± 0.7° and 1.2 ± 1.4 mm for 20-minute intervals. Small, but significant, misalignment is present in the co-registered diagnostic PET/CT and MRI/MRI images and can be corrected in SRS treatment planning using the volumetric image registration for improved target localization within the clinical error tolerance.


Assuntos
Cabeça/diagnóstico por imagem , Imageamento por Ressonância Magnética/métodos , Tomografia por Emissão de Pósitrons/métodos , Radiocirurgia/métodos , Tomografia Computadorizada por Raios X/métodos , Artefatos , Fluordesoxiglucose F18 , Humanos , Imageamento Tridimensional , Movimento (Física) , Imagens de Fantasmas , Fatores de Tempo
10.
Mol Cancer Res ; 6(2): 243-9, 2008 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-18314485

RESUMO

We have previously shown that hydrogen peroxide-resistant permanent (OC-14) cells are resistant to the cytotoxicity of several exogenous oxidative and anticancer agents including H(2)O(2), etoposide, and cisplatin; and we refer to this process as an oxidative multimodality-resistant phenotype (MMRP). Furthermore, OC-14 cells contain increased activator protein 1 activity, and inhibition of activator protein 1 reversed the MMRP. In this study, we show that permanent Rat-1 cell lines genetically altered to overexpress c-Fos also displayed a similar MMRP to H(2)O(2), etoposide, and cisplatin as OC-14 cells. Gene expression analysis of the OC-14 cells and c-Fos-overexpressing cells showed increased DNMT1 expression. Where OC-14 and c-Fos-overexpressing cells were exposed to 5-aza-2'-deoxycytidine, which inhibits DNMT activity, a significant but incomplete reversal of the MMRP was observed. Thus, it seems logical to suggest that DNMT1 might be at least one target in the MMRP. Rat-1 cells genetically altered to overexpress DNMT1 were also shown to be resistant to the cytotoxicity of H(2)O(2), etoposide, and cisplatin. Finally, somatic HCT116 knockout cells that do not express either DNMT1 (DNMT1(-/-)) or DNMT3B (DNMT3B(-/-)) were shown to be more sensitive to the cytotoxicity of H(2)O(2), etoposide, and cisplatin compared with control HCT116 cells. This work is the first example of a role for the epigenome in tumor cell resistance to the cytotoxicity of exogenous oxidative (H(2)O(2)) or systemic (etoposide and cisplatin) agents and highlights a potential role for DNMT1 as a potential molecular target in cancer therapy.


Assuntos
DNA (Citosina-5-)-Metiltransferases/metabolismo , Resistencia a Medicamentos Antineoplásicos , Neoplasias/enzimologia , Neoplasias/patologia , Animais , Antineoplásicos/farmacologia , Azacitidina/farmacologia , Linhagem Celular Tumoral , DNA (Citosina-5-)-Metiltransferase 1 , DNA (Citosina-5-)-Metiltransferases/deficiência , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Peróxido de Hidrogênio/farmacologia , Estresse Oxidativo/efeitos dos fármacos , Fenótipo , Proteínas Proto-Oncogênicas c-fos/metabolismo , Ratos , DNA Metiltransferase 3B
11.
Phys Med Biol ; 54(7): 1963-78, 2009 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-19265201

RESUMO

An external respiratory surrogate that not only highly correlates with but also quantitatively predicts internal tidal volume should be useful in guiding four-dimensional computed tomography (4DCT), as well as 4D radiation therapy (4DRT). A volumetric surrogate should have advantages over external fiducial point(s) for monitoring respiration-induced motion of the torso, which deforms in synchronization with a patient-specific breathing pattern. This study establishes a linear relationship between the external torso volume change (TVC) and lung air volume change (AVC) by validating a proposed volume conservation hypothesis (TVC = AVC) throughout the respiratory cycle using 4DCT and spirometry. Fourteen patients' torso 4DCT images and corresponding spirometric tidal volumes were acquired to examine this hypothesis. The 4DCT images were acquired using dual surrogates in ciné mode and amplitude-based binning in 12 respiratory stages, minimizing residual motion artifacts. Torso and lung volumes were calculated using threshold-based segmentation algorithms and volume changes were calculated relative to the full-exhalation stage. The TVC and AVC, as functions of respiratory stages, were compared, showing a high correlation (r = 0.992 +/- 0.005, p < 0.0001) as well as a linear relationship (slope = 1.027 +/- 0.061, R(2) = 0.980) without phase shift. The AVC was also compared to the spirometric tidal volumes, showing a similar linearity (slope = 1.030 +/- 0.092, R(2) = 0.947). In contrast, the thoracic and abdominal heights measured from 4DCT showed relatively low correlation (0.28 +/- 0.44 and 0.82 +/- 0.30, respectively) and location-dependent phase shifts. This novel approach establishes the foundation for developing an external volumetric respiratory surrogate.


Assuntos
Tamanho Corporal , Movimento , Respiração , Tomografia Computadorizada por Raios X/métodos , Abdome/anatomia & histologia , Abdome/fisiologia , Ar , Gases , Trato Gastrointestinal/diagnóstico por imagem , Trato Gastrointestinal/metabolismo , Humanos , Modelos Lineares , Pulmão/anatomia & histologia , Pulmão/fisiologia , Pressão , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Tórax/anatomia & histologia , Tórax/fisiologia , Volume de Ventilação Pulmonar
12.
Phys Med Biol ; 54(13): 4113-30, 2009 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-19521009

RESUMO

An analytical approach to predict respiratory diaphragm motion should have advantages over a correlation-based method, which cannot adapt to breathing pattern changes without re-calibration for a changing correlation and/or linear coefficient. To quantitatively calculate the diaphragm motion, a new expandable 'piston' respiratory (EPR) model was proposed and tested using 4DCT torso images of 14 patients. The EPR model allows two orthogonal lung motions (with a few volumetric constraints): (1) the lungs expand (DeltaV(EXP)) with the same anterior height variation as the thoracic surface, and (2) the lungs extend (DeltaV(EXT)) with the same inferior distance as the volumetrically equivalent 'piston' diaphragm. A volume conservation rule (VCR) established previously (Li et al 2009 Phys. Med. Biol. 54 1963-78) was applied to link the external torso volume change (TVC) to internal lung volume change (LVC) via lung air volume change (AVC). As the diaphragm moves inferiorly, the vacant space above the diaphragm inside the rib cage should be filled by lung tissue with a volume equal to DeltaV(EXT) (=LVC-DeltaV(EXP)), while the volume of non-lung tissues in the thoracic cavity should conserve. It was found that DeltaV(EXP) accounted for 3-24% of the LVC in these patients. The volumetric shape of the rib cage, characterized by the variation of cavity volume per slice over the piston motion range, deviated from a hollow cylinder by -1.1% to 6.0%, and correction was made iteratively if the variation is >3%. The predictions based on the LVC and TVC (with a conversion factor) were compared with measured diaphragm displacements (averaged from six pivot points), showing excellent agreements (0.2 +/- 0.7 mm and 0.2 +/- 1.2 mm, respectively), which are within clinically acceptable tolerance. Assuming motion synchronization between the piston and points of interest along the diaphragm, point motion was estimated but at higher uncertainty ( approximately 10% +/- 4%). This analytical approach provides a patient-independent technique to calculate the patient-specific diaphragm motion, using the anatomical and respiratory volumetric constraints.


Assuntos
Diafragma/fisiologia , Imageamento Tridimensional/métodos , Modelos Biológicos , Interpretação de Imagem Radiográfica Assistida por Computador/métodos , Radiografia Torácica/métodos , Mecânica Respiratória/fisiologia , Tórax/fisiologia , Algoritmos , Simulação por Computador , Diafragma/diagnóstico por imagem , Humanos , Tamanho do Órgão/fisiologia , Tomografia Computadorizada por Raios X/métodos
13.
Surg Clin North Am ; 88(3): 629-46, viii, 2008 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-18514703

RESUMO

Sarcomas represent a heterogeneous, challenging, and rare group of tumors that present many management challenges. In this article, the authors concentrate on the radiotherapeutic management of sarcomas occurring in the most common locations: the extremities, the trunk, and the retroperitoneum. An overview of the current radiotherapeutic management of soft tissue sarcoma is presented in addition to a discussion of how surgical management may affect radiotherapeutic management. Finally, the authors describe current controversies surrounding the appropriate management of sarcomas with radiotherapy and describe ongoing studies and future areas of research.


Assuntos
Sarcoma/radioterapia , Braquiterapia , Humanos , Terapia Neoadjuvante , Dosagem Radioterapêutica , Radioterapia Adjuvante , Neoplasias Retroperitoneais/radioterapia , Sarcoma/cirurgia
14.
Diagn Interv Radiol ; 24(1): 46-53, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29317377

RESUMO

PURPOSE: Prostate multiparametric magnetic resonance imaging (mpMRI) has utility in detecting post-radiotherapy local recurrence. We conducted a multireader study to evaluate the diagnostic performance of mpMRI for local recurrence after low dose rate (LDR) brachytherapy. METHODS: A total of 19 patients with biochemical recurrence after LDR brachytherapy underwent 3T endorectal coil mpMRI with T2-weighted imaging, dynamic contrast-enhanced imaging (DCE) and diffusion-weighted imaging (DWI) with pathologic confirmation. Prospective reads by an experienced prostate radiologist were compared with reads from 4 radiologists of varying experience. Readers identified suspicious lesions and rated each MRI detection parameter. MRI-detected lesions were considered true-positive with ipsilateral pathologic confirmation. Inferences for sensitivity, specificity, positive predictive value (PPV), kappa, and index of specific agreement were made with the use of bootstrap resampling. RESULTS: Pathologically confirmed recurrence was found in 15 of 19 patients. True positive recurrences identified by mpMRI were frequently located in the transition zone (46.7%) and seminal vesicles (30%). On patient-based analysis, average sensitivity of mpMRI was 88% (standard error [SE], 3.5%). For highly suspicious lesions, specificity of mpMRI was 75% (SE, 16.5%). On lesion-based analysis, the average PPV was 62% (SE, 6.7%) for all lesions and 78.7% (SE, 10.3%) for highly suspicious lesions. The average PPV for lesions invading the seminal vesicles was 88.8% (n=13). The average PPV was 66.6% (SE, 5.8%) for lesions identified with T2-weighted imaging, 64.9% (SE, 7.3%) for DCE, and 70% (SE, 7.3%) for DWI. CONCLUSION: This series provides evidence that mpMRI after LDR brachytherapy is feasible with a high patient-based cancer detection rate. Radiologists of varying experience demonstrated moderate agreement in detecting recurrence.


Assuntos
Braquiterapia/métodos , Imageamento por Ressonância Magnética/métodos , Recidiva Local de Neoplasia/diagnóstico por imagem , Neoplasias da Próstata/diagnóstico por imagem , Neoplasias da Próstata/radioterapia , Idoso , Idoso de 80 Anos ou mais , Meios de Contraste , Imagem de Difusão por Ressonância Magnética , Humanos , Aumento da Imagem , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Próstata/diagnóstico por imagem , Doses de Radiação , Reprodutibilidade dos Testes , Estudos Retrospectivos , Sensibilidade e Especificidade
16.
Int J Radiat Oncol Biol Phys ; 97(5): 947-951, 2017 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-28333017

RESUMO

PURPOSE: Targeted magnetic resonance imaging (MRI)/ultrasound fusion prostate biopsy (MRI-Bx) has recently been compared with the standard of care extended sextant ultrasound-guided prostate biopsy (SOC-Bx), with the former associated with an increased rate of detection of clinically significant prostate cancer. The present study sought to determine the influence of MRI-Bx on radiation therapy and androgen deprivation therapy (ADT) recommendations. METHODS AND MATERIALS: All patients who had received radiation treatment and had undergone SOC-Bx and MRI-Bx at our institution were included. Using the clinical T stage, pretreatment prostate-specific antigen, and Gleason score, patients were categorized into National Comprehensive Cancer Network risk groups and radiation treatment or ADT recommendations assigned. Intensification of the recommended treatment after multiparametric MRI, SOC-Bx, and MRI-Bx was evaluated. RESULTS: From January 2008 to January 2016, 73 patients received radiation therapy at our institution after undergoing a simultaneous SOC-Bx and MRI-Bx (n=47 with previous SOC-Bx). Repeat SOC-Bx and MRI-Bx resulted in frequent upgrading compared with previous SOC-Bx (Gleason score 7, 6.7% vs 44.6%; P<.001; Gleason score 8-10, 2.1% vs 38%; P<.001). MRI-Bx increased the proportion of patients classified as very high risk from 24.7% to 41.1% (P=.027). Compared with SOC-Bx alone, including the MRI-Bx findings resulted in a greater percentage of pathologically positive cores (mean 37% vs 44%). Incorporation of multiparametric MRI and MRI-Bx results increased the recommended use and duration of ADT (duration increased in 28 of 73 patients and ADT was added for 8 of 73 patients). CONCLUSIONS: In patients referred for radiation treatment, MRI-Bx resulted in an increase in the percentage of positive cores, Gleason score, and risk grouping. The benefit of treatment intensification in accordance with the MRI-Bx findings is unknown.


Assuntos
Tomada de Decisão Clínica/métodos , Biópsia Guiada por Imagem/métodos , Imageamento por Ressonância Magnética/métodos , Neoplasias da Próstata/patologia , Neoplasias da Próstata/radioterapia , Ultrassonografia/métodos , Adulto , Idoso , Humanos , Masculino , Pessoa de Meia-Idade , Imagem Multimodal/métodos , Seleção de Pacientes , Neoplasias da Próstata/diagnóstico por imagem , Radioterapia Guiada por Imagem/métodos , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
17.
Cancer Res ; 63(12): 3413-7, 2003 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-12810678

RESUMO

Exposure to ionizing radiation is believed to cause cell injury via the production of free radicals that are thought to induce oxidative damage. It has been proposed that exposure to agents that enhance oxidative stress-induced injury by disrupting thiol metabolism may sensitize cells to the cytotoxic effects of ionizing radiation. Recently, it has been shown that glucose deprivation selectively induces cell injury in transformed human cells via metabolic oxidative stress (J. Biol. Chem., 273: 5294-5299; Ann. N.Y. Acad. Sci., 899: 349-362), resulting in profound disruptions in thiol metabolism. Because 2-deoxy-D-glucose (2DG) is a potent inhibitor of glucose metabolism thought to mimic glucose deprivation in vivo, the hypothesis that exposure to 2DG might be capable of inducing radiosensitization in transformed cells via perturbations in thiol metabolism was tested. When HeLa cells were exposed to 2DG (4-10 mM) for 4-72 h, cell survival decreased (20-90%) in a dose- and time-dependent fashion. When HeLa cells were treated with 6 mM 2DG for 16 h before ionizing radiation exposure, radiosensitization was observed with a sensitizer enhancement ratio of 1.4 at 10% isosurvival. Treatment with 2DG was also found to cause decreases in intracellular total glutathione content (50%). Simultaneous treatment with the thiol antioxidant N-acetylcysteine (NAC; 30 mM) protected HeLa cells against the cytotoxicity and radiosensitizing effects of 2DG, without altering radiosensitivity in the absence of 2DG. Furthermore, treatment with NAC partially reversed the 2DG-induced decreases in total glutathione content, as well as augmented intracellular cysteine content. Finally, the cytotoxicity and radiosensitizing effects of 2DG were more pronounced in v-Fos-transformed versus nontransformed immortalized rat cells, and this radiosensitization was also inhibited by treatment with NAC. These results support the hypothesis that exposure to 2DG causes cytotoxicity and radiosensitization via a mechanism involving perturbations in thiol metabolism and allows for the speculation that these effects may be more pronounced in transformed versus normal cells.


Assuntos
Desoxiglucose/toxicidade , Radiossensibilizantes/toxicidade , Compostos de Sulfidrila/metabolismo , Acetilcisteína/farmacologia , Animais , Antioxidantes/farmacologia , Linhagem Celular Transformada/efeitos dos fármacos , Linhagem Celular Transformada/efeitos da radiação , Transformação Celular Viral , Cisteína/metabolismo , Desoxiglucose/farmacologia , Relação Dose-Resposta a Droga , Fibroblastos/efeitos dos fármacos , Fibroblastos/metabolismo , Fibroblastos/efeitos da radiação , Radicais Livres , Genes fos , Glucose/antagonistas & inibidores , Glucose/metabolismo , Glutationa/metabolismo , Células HeLa/efeitos dos fármacos , Células HeLa/metabolismo , Células HeLa/efeitos da radiação , Humanos , Proteínas Oncogênicas v-fos/fisiologia , Oxirredução , Estresse Oxidativo , Protetores contra Radiação/farmacologia , Radiossensibilizantes/farmacologia , Ratos , Ensaio Tumoral de Célula-Tronco
18.
Cancer Res ; 63(24): 8984-95, 2003 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-14695217

RESUMO

Ansamycin antibiotics inhibit function of the heat shock protein (HSP) 90, causing selective degradation of several intracellular proteins regulating such processes as proliferation, cell cycle regulation, and prosurvival signaling cascades. HSP90 has been identified previously as a molecular target for anticancer agents, including ionizing radiation (IR). Therefore, we hypothesized that the ansamycin geldanamycin and its 17-allylamino-17-demethoxy analog (17-AAG), which inhibit HSP90, would enhance tumor cell susceptibility to the cytotoxicity of IR. Treatment of two human cervical carcinoma cell lines (HeLa and SiHa) with geldanamycin and 17-AAG resulted in cytotoxicity and, when combined with IR, enhanced the radiation response, each effect with a temporal range from 6 to 48 h after drug exposure. In addition, mouse in vivo models using 17-AAG at clinically achievable concentrations yielded results that paralleled the in vitro radiosensitization studies of both single and fractioned courses of irradiation. The increase in IR-induced cell death appears to be attributable to a combination of both programmed and nonprogrammed cell death. We also measured total levels of several prosurvival and apoptotic signaling proteins. Akt1, extracellular signal-regulated kinase-1, Glut-1, HER-2/neu, Lyn, cAMP-dependent protein kinase, Raf-1, and vascular endothelial growth factor expression were down-regulated in 17-AAG-treated cells, identifying these factors as molecular markers and potential therapeutic targets. Finally, a series of immortalized and human papillomavirus-transformed cell lines were used to demonstrate that the radiosensitizing effects of 17-AAG were limited to transformed cells, suggesting a possible differential cytotoxic effect. This work shows that altered HSP90 function induces significant tumor cytotoxicity and radiosensitization, suggesting a potential therapeutic utility.


Assuntos
Antibióticos Antineoplásicos/farmacologia , Proteínas de Choque Térmico HSP90/fisiologia , Quinonas/farmacologia , Radiossensibilizantes/farmacologia , Rifabutina/análogos & derivados , Rifabutina/farmacologia , Neoplasias do Colo do Útero/tratamento farmacológico , Neoplasias do Colo do Útero/radioterapia , Animais , Benzoquinonas , Terapia Combinada , Relação Dose-Resposta a Droga , Sinergismo Farmacológico , Feminino , Células HeLa , Humanos , Lactamas Macrocíclicas , Camundongos , Camundongos Endogâmicos C3H , Camundongos Nus , Transdução de Sinais/efeitos dos fármacos , Ensaios Antitumorais Modelo de Xenoenxerto
19.
Clin J Oncol Nurs ; 19(6): 744-50, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26583638

RESUMO

BACKGROUND: Fatigue is one of the most distressing symptoms experienced by people with cancer receiving radiation therapy. OBJECTIVES: The goal of this study is to evaluate clinical predictors of worsening fatigue during external beam radiation therapy (EBRT) in men with non-metastatic prostate cancer. METHODS: Thirty-five men with non-metastatic prostate cancer scheduled for EBRT were followed at baseline, midpoint, and completion of EBRT. The Functional Assessment of Cancer Therapy-Fatigue scale was administered. Demographic and clinical data were obtained by chart review. Paired t-tests, correlations, general linear models, and logistic regressions were used to determine associations between fatigue scores and clinical data. FINDINGS: Red blood cells, hemoglobin, and hematocrit levels were highly intercorrelated and, therefore, were grouped as one composite variable termed heme. Heme levels at baseline and androgen-deprivation therapy (ADT) were significantly correlated with worsening of fatigue symptoms from baseline to midpoint and endpoint. ADT alone did not have a significant correlation with fatigue, but it indirectly affected fatigue levels by influencing heme markers as treatment progressed. These findings provide evidence that hematologic markers and the use of ADT assist in predicting radiation therapy-related fatigue and guide symptom management.


Assuntos
Fadiga , Neoplasias da Próstata/radioterapia , Idoso , Humanos , Masculino , Modelos Teóricos , Neoplasias da Próstata/fisiopatologia
20.
Clin Lung Cancer ; 16(6): 413-30, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26027433

RESUMO

Lung cancer is among the most common cancers worldwide and is the leading cause of cancer death in both men and women. For patients with early stage (American Joint Committee on Cancer T1-2, N0) non-small-cell lung cancer, the current standard of care is lobectomy with systematic lymph node evaluation. Unfortunately, patients with lung cancer often have medical comorbities, which may preclude the option of surgical resection. In such cases, a number of minimally invasive to noninvasive treatment options have gained popularity in the treatment of these high-risk patients. These modalities provide significant advantages, including patient convenience, treatment in an outpatient setting, and acceptable toxicities, including reduced impact on lung function and a modest risk of postprocedure chest wall pain. We provide a comprehensive review of the literature, including reported outcomes, complications, and limitations of sublobar resection with or without intraoperative brachytherapy, radiofrequency ablation, microwave ablation, percutaneous cryoablation, photodynamic therapy, and stereotactic body radiotherapy.


Assuntos
Braquiterapia , Carcinoma Pulmonar de Células não Pequenas/radioterapia , Ablação por Cateter , Neoplasias Pulmonares/radioterapia , Fotoquimioterapia , Assistência Ambulatorial , Carcinoma Pulmonar de Células não Pequenas/cirurgia , Contraindicações , Criocirurgia , Humanos , Neoplasias Pulmonares/cirurgia , Pneumonectomia , Radiocirurgia , Risco , Resultado do Tratamento
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