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1.
Lancet Oncol ; 25(5): e217-e224, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38697167

RESUMO

Caribbean small island developing states are becoming increasingly vulnerable to compounding disasters, prominently featuring climate-related hazards and pandemic diseases, which exacerbate existing barriers to cancer control in the region. We describe the complexities of cancer prevention and control efforts throughout the Caribbean small island developing states, including the unique challenges of people diagnosed with cancer in the region. We highlight potential solutions and strategies that concurrently address disaster adaptation and cancer control. Because Caribbean small island developing states are affected first and worst by the hazards of compounding disasters, the innovative solutions developed in the region are relevant for climate mitigation, disaster adaptation, and cancer control efforts globally. In the age of complex and cascading disaster scenarios, developing strategies to mitigate their effect on the cancer control continuum, and protecting the health and safety of people diagnosed with cancer from extreme events become increasingly urgent. The equitable development of such strategies relies on collaborative efforts among professionals whose diverse expertise from complementary fields infuses the local community perspective while focusing on implementing solutions.


Assuntos
Neoplasias , Humanos , Neoplasias/epidemiologia , Neoplasias/diagnóstico , Neoplasias/prevenção & controle , Região do Caribe/epidemiologia , Desastres , Planejamento em Desastres/organização & administração
2.
J Appl Clin Med Phys ; 24(4): e13899, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36637862

RESUMO

Prostate-specific membrane antigen (PSMA) is a cell surface protein highly expressed in nearly all prostate cancers, with restricted expression in some normal tissues. The differential expression of PSMA from tumor to non-tumor tissue has resulted in the investigation of numerous targeting strategies for therapy of patients with metastatic prostate cancer. In March of 2022, the FDA granted approval for the use of lutetium-177 PSMA-617 (Lu-177-PSMA-617) for patients with PSMA-positive metastatic castration-resistant prostate cancer (mCRPC) who have been treated with androgen receptor pathway inhibition and taxane-based chemotherapy. Therefore, the use of Lu-177-PSMA-617 is expected to increase and become more widespread. Herein, we describe logistical, technical, and radiation safety considerations for implementing a radiopharmaceutical therapy program, with particular focus on the development of operating procedures for therapeutic administrations. Major steps for a center in the U.S. to implement a new radiopharmaceutical therapy (RPT) program are listed below, and then demonstrated in greater detail via examples for Lu-177-PSMA-617 therapy.


Assuntos
Lutécio , Neoplasias de Próstata Resistentes à Castração , Compostos Radiofarmacêuticos , Humanos , Masculino , Lutécio/uso terapêutico , Próstata , Antígeno Prostático Específico , Neoplasias de Próstata Resistentes à Castração/radioterapia , Neoplasias de Próstata Resistentes à Castração/tratamento farmacológico , Neoplasias de Próstata Resistentes à Castração/metabolismo , Compostos Radiofarmacêuticos/uso terapêutico , Resultado do Tratamento
3.
Int J Cancer ; 150(3): 521-531, 2022 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-34655477

RESUMO

Increasing evidence has elucidated the clinicopathological significance of tumor microenvironment (TME) cells. However, TME differences associated with human papillomavirus (HPV) infection in oropharyngeal squamous cell carcinoma (OPSCC) have not been well characterized. In our study, we comprehensively determined the TME infiltration patterns in 315 OPSCC patients, and systematically correlated the TME phenotypes with genomic characteristics and clinical features of OPSCCs. In this way, we observed the enrichment of high endothelial cells and adaptive immune cells in HPV-positive (HPV+) OPSCCs, in contrast to the enrichment of fibroblasts and capillary endothelial cells in HPV- negative (HPV-) OPSCCs. By focusing on immune checkpoint genes, we constructed a coexpression network using genes that were differentially expressed between HPV+ and HPV- OPSCCs. Functional analysis of the network indicated that HPV+ OPSCCs had elevated immune activities by promoting adaptive immune response and suppressing activities related to extracellular matrix organization. Subsequently, clinical analysis showed that identified TME-relevant genes were closely associated with the prognosis and therapy response in OPSCC. Importantly, results from the TME analysis were further validated using an independent OPSCC cohort.


Assuntos
Neoplasias Orofaríngeas/virologia , Papillomaviridae/isolamento & purificação , Carcinoma de Células Escamosas de Cabeça e Pescoço/virologia , Microambiente Tumoral/fisiologia , Comunicação Celular , Feminino , Humanos , Proteínas de Checkpoint Imunológico/genética , Masculino , Pessoa de Meia-Idade , Neoplasias Orofaríngeas/mortalidade , Neoplasias Orofaríngeas/patologia , Prognóstico , Carcinoma de Células Escamosas de Cabeça e Pescoço/mortalidade , Carcinoma de Células Escamosas de Cabeça e Pescoço/patologia
4.
Bioinformatics ; 37(19): 3106-3114, 2021 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-34237137

RESUMO

MOTIVATION: Predicting early in treatment whether a tumor is likely to respond to treatment is one of the most difficult yet important tasks in providing personalized cancer care. Most oropharyngeal squamous cell carcinoma (OPSCC) patients receive standard cancer therapy. However, the treatment outcomes vary significantly and are difficult to predict. Multiple studies indicate that microRNAs (miRNAs) are promising cancer biomarkers for the prognosis of oropharyngeal cancer. The reliable and efficient use of miRNAs for patient stratification and treatment outcome prognosis is still a very challenging task, mainly due to the relatively high dimensionality of miRNAs compared to the small number of observation sets; the redundancy, irrelevancy and uncertainty in the large amount of miRNAs; and the imbalanced observation patient samples. RESULTS: In this study, a new machine learning-based prognosis model was proposed to stratify subsets of OPSCC patients with low and high risks for treatment failure. The model cascaded a two-stage prognostic biomarker selection method and an evidential K-nearest neighbors classifier to address the challenges and improve the accuracy of patient stratification. The model has been evaluated on miRNA expression profiling of 150 oropharyngeal tumors by use of overall survival and disease-specific survival as the end points of disease treatment outcomes, respectively. The proposed method showed superior performance compared to other advanced machine-learning methods in terms of common performance quantification metrics. The proposed prognosis model can be employed as a supporting tool to identify patients who are likely to fail standard therapy and potentially benefit from alternative targeted treatments.Availability and implementation: Code is available in https://github.com/shenghh2015/mRMR-BFT-outcome-prediction.

5.
J Urol ; 207(6): 1227-1235, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35085038

RESUMO

PURPOSE: Men with unfavorable intermediate-risk (UIR-PCa) or high-risk prostate cancer (HR-PCa) are often treated with definitive external beam radiotherapy (EBRT) plus androgen deprivation therapy. Treatment is frequently intensified by electively treating the pelvic lymph nodes (LNs) with whole pelvis radiotherapy (WPRT), but practice patterns and the benefits of WPRT are not well defined. We hypothesized that men treated with WPRT would have improved overall survival (OS) relative to men treated with prostate-only radiotherapy. MATERIALS AND METHODS: National Cancer Database records of men diagnosed between 2008-2015 with UIR-PCa or HR-PCa and treated with prostate EBRT±androgen deprivation therapy (72-86.4 Gy) with (15,175) or without (13,549) WPRT were reviewed. Risk of LN involvement was calculated using the Memorial Sloan Kettering Cancer Center nomogram. Measured confounders were balanced with inverse probability of treatment weighting and OS hazard ratios (HRs) were generated using multivariable Cox regression. RESULTS: Of the men, 53% received WPRT. Every 1% increase in risk of LN involvement correlated with a 1% increase in risk of death (p <0.001). WPRT trended toward improved OS in all men with UIR-PCa and HR-PCa (HR: 0.95 [95% CI: 0.90-1.006], p=0.055). WPRT correlated with improved OS in men with Gleason 9 and 10 disease (HR: 0.87 [0.78-0.98], p=0.02) or risk of LN involvement ≥10% (HR: 0.93 [0.87-0.99], p=0.03). CONCLUSIONS: Men with higher LN risk scores and Gleason grade benefited from WPRT. These results complement the recent POP-RT randomized trial in mostly positron emission tomography/computerized tomography-staged patients, demonstrating that a more heterogeneous population of men staged without functional imaging benefits from WPRT.


Assuntos
Próstata , Neoplasias da Próstata , Antagonistas de Androgênios/uso terapêutico , Androgênios , Humanos , Masculino , Pelve , Próstata/patologia , Neoplasias da Próstata/patologia , Neoplasias da Próstata/radioterapia
6.
J Natl Compr Canc Netw ; 20(4): 343-350.e4, 2022 02 22.
Artigo em Inglês | MEDLINE | ID: mdl-35193114

RESUMO

BACKGROUND: The NCCN Guidelines for Prostate Cancer currently recommend several definitive radiotherapy (RT) options for men with unfavorable intermediate-risk (UIR) prostate cancer: external-beam RT (EBRT) plus androgen deprivation therapy (ADT) or EBRT plus brachytherapy boost with or without ADT. However, brachytherapy alone with or without ADT is not well defined and is currently not recommended for UIR prostate cancer. We hypothesized that men treated with brachytherapy with or without ADT have comparable survival rates to men treated with EBRT with or without ADT. METHODS: A total of 31,783 men diagnosed between 2004 and 2015 with UIR prostate cancer were retrospectively reviewed from the National Cancer Database. Men were stratified into 4 groups: EBRT (n=12,985), EBRT plus ADT (n=12,960), brachytherapy (n=4,535), or brachytherapy plus ADT (n=1,303). Inverse probability of treatment weighting (IPTW) was used to adjust for covariable imbalances, and weight-adjusted multivariable analysis (MVA) using Cox regression modeling was used to compare overall survival (OS) hazard ratios (HRs). RESULTS: Relative to EBRT alone, the following treatments were associated with improved OS: EBRT plus ADT (HR, 0.92; 95% CI, 0.87-0.97; P=.002), brachytherapy alone (HR, 0.90; 95% CI, 0.83-0.98; P=.01), and brachytherapy plus ADT (HR, 0.78; 95% CI, 0.69-0.88; P=.00006). Brachytherapy correlated with improved OS relative to EBRT in men who were not treated with ADT (HR, 0.92; 95% CI, 0.84-0.99; P=.03) and in those receiving ADT (HR, 0.84; 95% CI, 0.75-0.95; P=.004). At 10-year follow-up, 56% and 63% of men receiving EBRT and brachytherapy, respectively, were alive (P<.0001). IPTW was used to determine the average treatment effect of definitive brachytherapy. Relative to EBRT, definitive brachytherapy correlated with improved OS (HR, 0.90; 95% CI, 0.84-0.97; P=.009) on weight-adjusted MVA. CONCLUSIONS: Definitive brachytherapy was associated with improved OS compared with EBRT. The addition of ADT to both EBRT and definitive brachytherapy was associated with improved OS. These results suggest that definitive brachytherapy should be considered as an option for men with UIR prostate cancer.


Assuntos
Braquiterapia , Neoplasias da Próstata , Masculino , Humanos , Braquiterapia/métodos , Neoplasias da Próstata/terapia , Antagonistas de Androgênios/uso terapêutico , Estudos Retrospectivos , Modelos de Riscos Proporcionais
7.
Cancer ; 126(17): 3900-3906, 2020 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-32478867

RESUMO

During the coronavirus disease 2019 (COVID-19) pandemic, providers and patients must engage in shared decision making regarding the pros and cons of early versus delayed interventions for localized skin cancer. Patients at highest risk of COVID-19 complications are older; are immunosuppressed; and have diabetes, cancer, or cardiopulmonary disease, with multiple comorbidities associated with worse outcomes. Physicians must weigh the patient's risk of COVID-19 complications in the event of exposure against the risk of worse oncologic outcomes from delaying cancer therapy. Herein, the authors have summarized current data regarding the risk of COVID-19 complications and mortality based on age and comorbidities and have reviewed the literature assessing how treatment delays affect oncologic outcomes. They also have provided multidisciplinary recommendations regarding the timing of local therapy for early-stage skin cancers during this pandemic with input from experts at 11 different institutions. For patients with Merkel cell carcinoma, the authors recommend prioritizing treatment, but a short delay can be considered for patients with favorable T1 disease who are at higher risk of COVID-19 complications. For patients with melanoma, the authors recommend delaying the treatment of patients with T0 to T1 disease for 3 months if there is no macroscopic residual disease at the time of biopsy. Treatment of tumors ≥T2 can be delayed for 3 months if the biopsy margins are negative. For patients with cutaneous squamous cell carcinoma, those with Brigham and Women's Hospital T1 to T2a disease can have their treatment delayed for 2 to 3 months unless there is rapid growth, symptomatic lesions, or the patient is immunocompromised. The treatment of tumors ≥T2b should be prioritized, but a 1-month to 2-month delay is unlikely to worsen disease-specific mortality. For patients with squamous cell carcinoma in situ and basal cell carcinoma, treatment can be deferred for 3 months unless the individual is highly symptomatic.


Assuntos
Betacoronavirus , Tomada de Decisão Clínica/métodos , Infecções por Coronavirus/epidemiologia , Infecções por Coronavirus/terapia , Médicos/psicologia , Pneumonia Viral/epidemiologia , Pneumonia Viral/terapia , Neoplasias Cutâneas/epidemiologia , Neoplasias Cutâneas/terapia , COVID-19 , Comorbidade , Infecções por Coronavirus/mortalidade , Infecções por Coronavirus/virologia , Humanos , Hospedeiro Imunocomprometido , Morbidade , Pandemias , Pneumonia Viral/mortalidade , Pneumonia Viral/virologia , SARS-CoV-2 , Tempo para o Tratamento
8.
BJU Int ; 126(3): 367-372, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32333714

RESUMO

OBJECTIVE: To evaluate the long-term bowel-associated quality of life (QOL) in men after radiotherapy (RT) for prostate cancer with and without the use of rectal hydrogel spacer. PATIENTS AND METHODS: The patients' QOL was examined using the Expanded Prostate Cancer Index Composite (EPIC) and mean changes from baseline in EPIC domains were evaluated. A total of 215 patients from a randomised multi-institutional trial of RT, with or without hydrogel spacer, with a QOL endpoint were pooled with 165 non-randomised patients from a single institution with prospective QOL collection in patients with or without hydrogel spacer. The proportions of men with minimally important differences (MIDs) relative to pre-treatment baseline in the bowel domain were tested using repeated measure logistic models with a pre-specified threshold for clinically significant declines (≥5 equivalent to MIDx1 and ≥10 equivalent to MIDx2). RESULTS: A total of 380 men were evaluated (64% with spacer and 36% without) with QOL data being available for 199 men with >24 months of follow-up [median (range) 39.5 (31-71.4) months]. Treatment with spacer was associated with less decline in average long-term bowel QOL (89.4 for control and 94.7 for spacer) with differences at >24 months meeting the threshold of a MID difference between cohorts (bowel score difference from baseline: control = -5.1, spacer = 0.3, difference = -5.4; P < 0.001). When evaluated over time men without spacer were more likely to have MIDx1 (5 points) declines in bowel QOL (P = 0.01). At long-term follow-up MIDx1 was 36% without spacer vs 14% with spacer (P <0.001; odds ratio [OR] 3.5, 95% CI 1.7-6.9) while MIDx2 was seen in 19% vs 6% (P = 0.008; OR 3.6, 95% CI 1.4-9.1). The use of spacer was associated with less urgency with bowel movements (P = 0.002) and fewer loose stools (P = 0.009), as well as less bother with urgency (P = 0.007) and frequency of bowel movements (P = 0.009). CONCLUSIONS: In this pooled analysis of QOL after prostate RT with up to 5 years of follow-up, use of a rectal spacer was associated with preservation of bowel QOL. This QOL benefit was preserved with long-term follow-up.


Assuntos
Hidrogéis , Neoplasias da Próstata/radioterapia , Qualidade de Vida , Idoso , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Radioterapia/métodos , Reto , Método Simples-Cego , Fatores de Tempo
9.
J Urol ; 199(2): 416-423, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-28842247

RESUMO

PURPOSE: Elderly patients with muscle invasive bladder cancer can pose a therapeutic dilemma, given multiple comorbidities which may preclude surgery. In this registry based analysis we investigated treatment patterns and survival outcomes in this group of patients. MATERIALS AND METHODS: We queried the National Cancer Database for muscle invasive (cT2-T4aN0M0) bladder cancer in patients 80 years old or older who were diagnosed from 2004 to 2013. Patients included in study underwent transurethral resection of bladder tumor followed by radical cystectomy, radical cystectomy plus chemotherapy, radiation therapy alone, chemotherapy alone, chemoradiation or no treatment. We performed Kaplan-Meier, log rank and multivariate Cox proportional hazards regression and propensity score matching. RESULTS: A total of 9,270 patients were identified with a median followup of 12.8 months. Median overall survival in patients treated with radical cystectomy alone was 23.2 months (95% CI 19.8-26.6), which was superior to that of chemotherapy alone or radiation therapy alone (p <0.0001). Those treated with chemoradiation had a median overall survival of 27.3 months (95% CI 25.0-29.7), which did not statistically differ from that of radical cystectomy alone (p = 0.39). Surgery plus chemotherapy showed the longest median overall survival of 34.5 months (95% CI 22.2-46.7, vs chemoradiation and radical cystectomy alone p <0.0001). On multivariate analysis and propensity score matching the best overall survival was seen in patients treated with surgery plus chemotherapy and there was no difference in overall survival between chemoradiation and radical cystectomy alone. CONCLUSIONS: In elderly patients with muscle invasive bladder cancer chemoradiation is an alternative definitive treatment strategy with survival equal to that of surgery alone and superior to that of chemotherapy alone or radiation therapy alone. If a patient was able to receive neoadjuvant or adjuvant chemotherapy with surgery, additional survival was observed in this nonrandomized study.


Assuntos
Carcinoma de Células de Transição/mortalidade , Carcinoma de Células de Transição/terapia , Padrões de Prática Médica/estatística & dados numéricos , Neoplasias da Bexiga Urinária/mortalidade , Neoplasias da Bexiga Urinária/terapia , Fatores Etários , Idoso de 80 Anos ou mais , Carcinoma de Células de Transição/patologia , Quimiorradioterapia Adjuvante , Cistectomia , Bases de Dados Factuais , Feminino , Seguimentos , Humanos , Masculino , Invasividade Neoplásica , Estadiamento de Neoplasias , Sistema de Registros , Estudos Retrospectivos , Análise de Sobrevida , Estados Unidos/epidemiologia , Neoplasias da Bexiga Urinária/patologia
10.
Mo Med ; 115(2): 146-150, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30228707

RESUMO

Annually, there are nearly 3000 new cases and 500 deaths from prostate cancer in Missouri. When treatment is appropriate and necessary, radiotherapy offers similar cure rates to prostatectomy, with fewer long-term sexual side effects and little effect on urinary continence. Radiotherapy is delivered with external beam or implanted radioactive sources (brachytherapy). In high-risk disease, combinations of external beam and brachytherapy offers improved biochemical control. Following prostatectomy, salvage radiotherapy should be initiated as soon as possible.


Assuntos
Braquiterapia/métodos , Neoplasias da Próstata/radioterapia , Terapia Combinada , Humanos , Masculino , Missouri/epidemiologia , Prostatectomia/métodos , Neoplasias da Próstata/mortalidade , Terapia de Salvação/métodos
12.
Cancer ; 123(23): 4594-4607, 2017 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-28881377

RESUMO

BACKGROUND: The authors hypothesized that unilateral intensity-modulated radiotherapy (IMRT) would decrease toxicity compared with bilateral IMRT for patients with lateralized palatine tonsillar cancer and a neck classification of N0 to N2b, with similar oncological outcomes. METHODS: A total of 154 patients were treated with postoperative IMRT from 1997 through 2013. Data were collected prospectively from 2005 to 2013 and retrospectively collected before 2005. Of those patients with lateralized primary and N0 to N2b disease, 48 received unilateral IMRT (group 1) and 59 received bilateral IMRT (group 2); a total of 47 patients had nonlateralized primary or N2c to N3 disease and received bilateral IMRT (group 3). RESULTS: The median follow-up was 5.5 years. The 5-year locoregional control rates were similar in group 1, group 2, and group 3 (100%, 96%, and 94%, respectively; pooled comparison: P = .39 and group 1 vs group 2 comparison: P = .19). The 5-year overall survival rates were similar in group 1, group 2, and group 3 (85%, 79%, and 76%, respectively; pooled comparison: P = .60 and group 1 vs group 2 comparison: P = .25). There were no contralateral neck recurrences noted among unilaterally treated patients. Unilateral IMRT reduced acute toxicity and improved patient-reported quality of life compared with bilateral IMRT. CONCLUSIONS: Unilateral IMRT appears to reduce acute toxicity and achieves oncological outcomes similar to those of bilateral IMRT in selected patients with lateralized palatine tonsillar cancer with a neck classification of N0 to N2b. Cancer 2017;123:4594-4607. © 2017 American Cancer Society.


Assuntos
Carcinoma de Células Escamosas/radioterapia , Recidiva Local de Neoplasia/radioterapia , Tonsila Palatina/efeitos da radiação , Qualidade de Vida , Radioterapia de Intensidade Modulada/métodos , Neoplasias Tonsilares/radioterapia , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma de Células Escamosas/secundário , Carcinoma de Células Escamosas/cirurgia , Feminino , Seguimentos , Humanos , Metástase Linfática , Masculino , Pessoa de Meia-Idade , Invasividade Neoplásica , Recidiva Local de Neoplasia/patologia , Recidiva Local de Neoplasia/cirurgia , Tonsila Palatina/patologia , Tonsila Palatina/cirurgia , Prognóstico , Estudos Prospectivos , Dosagem Radioterapêutica , Radioterapia Adjuvante , Estudos Retrospectivos , Taxa de Sobrevida , Neoplasias Tonsilares/patologia , Neoplasias Tonsilares/cirurgia
14.
J Natl Compr Canc Netw ; 15(11): 1383-1391, 2017 11.
Artigo em Inglês | MEDLINE | ID: mdl-29118230

RESUMO

Background: Management of metastatic (M1) nasopharyngeal cancer (NPC) is controversial; data suggest high overall survival (OS) rates with definitive chemoradiotherapy (CRT). Herein, we evaluated OS in patients with M1 NPC undergoing chemotherapy alone versus CRT. Methods: The National Cancer Data Base was queried for M1 NPC cases. Patients undergoing no/unknown chemotherapy and/or with unknown/nondefinitive radiotherapy (RT) doses (<60 Gy) were excluded. Logistic regression analysis ascertained clinical factors associated with RT administration. Kaplan-Meier analysis evaluated OS between both cohorts; Cox proportional hazards modeling assessed factors associated with OS. Survival was then evaluated between matched populations using inverse-probability-weighted regression adjustment. OS between groups was also measured in patients surviving ≥1 and ≥3 years to address bias from poor-prognostic subsets (eg, widely disseminated disease), and those receiving CRT ≤30 and ≤60 days of each other (surrogates for concurrent CRT) versus >30 and >60 days (sequential) of each other. Results: Of 555 patients, 296 (53%) received chemotherapy alone and 259 (47%) underwent CRT. Patients undergoing CRT more often had private insurance (P=.001) and lived in areas with higher education levels (P=.028). Median OS in the chemotherapy-only and CRT cohorts were 13.7 and 25.8 months, respectively (P<.001); differences persisted between matched populations (P<.001). On multivariate analysis, receipt of additional RT independently predicted for improved OS (P<.001). OS differences between cohorts remained apparent when evaluating patients surviving for ≥1 (P<.001) and ≥3 (P=.002) years. Patients who received concurrent or sequential CRT displayed improved OS over those receiving chemotherapy alone, for both the 30-day (P<.001) and 60-day cutoffs (P<.001). Conclusions: Patients with M1 NPC undergoing definitive RT and chemotherapy experienced higher survival than those receiving chemotherapy alone. Risk stratification and patient selection for such combined modality interventions is critical.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Carcinoma/terapia , Quimiorradioterapia/métodos , Neoplasias Nasofaríngeas/terapia , Padrões de Prática Médica/estatística & dados numéricos , Adulto , Idoso , Idoso de 80 Anos ou mais , Protocolos de Quimioterapia Combinada Antineoplásica/economia , Carcinoma/diagnóstico , Carcinoma/mortalidade , Carcinoma/secundário , Quimiorradioterapia/economia , Estudos de Coortes , Feminino , Humanos , Seguro Saúde/estatística & dados numéricos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Carcinoma Nasofaríngeo , Neoplasias Nasofaríngeas/diagnóstico , Neoplasias Nasofaríngeas/mortalidade , Neoplasias Nasofaríngeas/patologia , Neoplasias Nasofaríngeas/secundário , Seleção de Pacientes , Padrões de Prática Médica/economia , Medição de Risco , Taxa de Sobrevida , Resultado do Tratamento , Estados Unidos/epidemiologia , Adulto Jovem
15.
J Appl Clin Med Phys ; 17(4): 377-390, 2016 07 08.
Artigo em Inglês | MEDLINE | ID: mdl-27455472

RESUMO

CT image reconstruction is typically evaluated based on the ability to reduce the radiation dose to as-low-as-reasonably-achievable (ALARA) while maintaining acceptable image quality. However, the determination of common image quality metrics, such as noise, contrast, and contrast-to-noise ratio, is often insufficient for describing clinical radiotherapy task performance. In this study we designed and implemented a new comparative analysis method associating image quality, radiation dose, and patient size with radiotherapy task performance, with the purpose of guiding the clinical radiotherapy usage of CT reconstruction algorithms. The iDose4 iterative reconstruction algorithm was selected as the target for comparison, wherein filtered back-projection (FBP) reconstruction was regarded as the baseline. Both phantom and patient images were analyzed. A layer-adjustable anthropomorphic pelvis phantom capable of mimicking 38-58 cm lateral diameter-sized patients was imaged and reconstructed by the FBP and iDose4 algorithms with varying noise-reduction-levels, respectively. The resulting image sets were quantitatively assessed by two image quality indices, noise and contrast-to-noise ratio, and two clinical task-based indices, target CT Hounsfield number (for electron density determination) and structure contouring accuracy (for dose-volume calculations). Additionally, CT images of 34 patients reconstructed with iDose4 with six noise reduction levels were qualitatively evaluated by two radiation oncologists using a five-point scoring mechanism. For the phantom experiments, iDose4 achieved noise reduction up to 66.1% and CNR improvement up to 53.2%, compared to FBP without considering the changes of spatial resolution among images and the clinical acceptance of reconstructed images. Such improvements consistently appeared across different iDose4 noise reduction levels, exhibiting limited interlevel noise (< 5 HU) and target CT number variations (< 1 HU). The radiation dose required to achieve similar contouring accuracy decreased when using iDose4 in place of FBP, up to 32%. Contouring accuracy improvement for iDose4 images, when compared to FBP, was greater in larger patients than smaller-sized patients. Overall, the iDose4 algorithm provided superior radiation dose control while maintaining or improving task performance, when compared to FBP. The reader study on image quality improvement of patient cases shows that physicians preferred iDose4-reconstructed images on all cases compared to those from FBP algorithm with overall quality score: 1.21 vs. 3.15, p = 0.0022. However, qualitative evaluation strongly indicated that the radiation oncologists chose iDose4 noise reduction levels of 3-4 with additional consideration of task performance, instead of image quality metrics alone. Although higher iDose4 noise reduction levels improved the CNR through the further reduction of noise, there was pixelization of anatomical/tumor structures. Very-low-dose scans yielded severe photon starvation artifacts, which decreased target visualization on both FBP and iDose4 reconstructions, especially for the 58 cm phantom size. The iDose4 algorithm with a moderate noise reduction level is hence suggested for CT simulation and treatment planning. Quantitative task-based image quality metrics should be further investigated to accommodate additional clinical applications.


Assuntos
Algoritmos , Processamento de Imagem Assistida por Computador/métodos , Imagens de Fantasmas , Análise e Desempenho de Tarefas , Tomografia Computadorizada por Raios X/métodos , Humanos , Doses de Radiação , Intensificação de Imagem Radiográfica , Razão Sinal-Ruído , Tomografia Computadorizada por Raios X/instrumentação
16.
World J Urol ; 33(1): 69-75, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24647879

RESUMO

PURPOSE: The purpose of the study was to evaluate the utility of a 3 T pelvic magnetic resonance imaging (MRI) in detecting a local recurrence in post-prostatectomy prostate cancer patients prior to receiving adjuvant or salvage intensity-modulated radiation therapy (IMRT). METHODS: Ninety prostate cancer patients status post-prostatectomy with rising prostate-specific antigen (PSA) had a 3 T pelvic MRI prior to IMRT. The following variables were analyzed for predicting positive findings on MRI: initial presenting and initial post-op PSA, PSA at the time of imaging, PSA velocity, surgical margins, Gleason score, pathological stage, pre-RT digital rectal examination, and type of surgical prostatectomy. RESULTS: The only significant variable predictive of a positive MRI was positive margins. Specifically, 15 of 46 (33 %) patients with positive margins had a positive MRI, while 5 of 44 (11 %) patients with negative margins had a positive MRI. In the MRI positive group, the location of the positive findings on MRI corresponded with the pathology report in 9 of 12 (75 %) cases. CONCLUSION: Post-prostatectomy patients with pathologic positive margins are three times more likely to have positive findings on a 3 T MRI.


Assuntos
Imageamento por Ressonância Magnética , Recidiva Local de Neoplasia/diagnóstico , Prostatectomia , Neoplasias da Próstata/diagnóstico , Neoplasias da Próstata/cirurgia , Idoso , Idoso de 80 Anos ou mais , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasia Residual , Antígeno Prostático Específico , Neoplasias da Próstata/radioterapia , Radioterapia Adjuvante , Radioterapia de Intensidade Modulada , Terapia de Salvação , Sensibilidade e Especificidade , Resultado do Tratamento
17.
Cancer ; 120(24): 3994-4002, 2014 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-25143048

RESUMO

BACKGROUND: Radiation treatment volumes in head and neck squamous cell carcinoma (HNSCC) are controversial. The authors report the outcomes, patterns of failure, and quality of life (QOL) of patients who received treatment for HNSCC using intensity-modulated radiation therapy (IMRT) that eliminated the treatment of contralateral retropharyngeal lymph nodes (RPLNs) in the clinically uninvolved neck. METHODS: A prospective institutional database was used to identify patients who had primary oral cavity, oropharyngeal, hypopharyngeal, laryngeal, and unknown primary HNSCC for which they received IMRT. There were 3 temporal groups (generations 1-3). Generation 1 received comprehensive neck IMRT with parotid sparing, generation 2 eliminated the contralateral high level II (HLII) lymph nodes, and generation 3 further eliminated the contralateral RPLNs in the clinically uninvolved neck. Patterns of failure and survival analyses were completed, and QOL data measured using the MD Anderson Dysphagia Inventory were compared in a subset of patients from generations 1 and 3. RESULTS: In total, 748 patients were identified. Of the 488 patients who received treatment in generation 2 or 3, 406 had a clinically uninvolved contralateral neck. There were no failures in the spared RPLNs (95% confidence interval, 0%-1.3%) or in the high contralateral neck (95% confidence interval, 0%-0.7%). QOL data were compared between 44 patients in generation 1 and 51 patients in generation 3. QOL improved both globally and in all domains assessed for generation 3, in which reduced radiotherapy volumes were used (P < .007). CONCLUSIONS: For patients with locally advanced HNSCC, eliminating coverage to the contralateral HLII lymph nodes and contralateral RPLNs in the clinically uninvolved side of the neck is associated with minimal risk of failure in these regions and significantly improved patient-reported QOL.


Assuntos
Carcinoma de Células Escamosas/radioterapia , Neoplasias de Cabeça e Pescoço/radioterapia , Irradiação Linfática/efeitos adversos , Qualidade de Vida , Planejamento da Radioterapia Assistida por Computador/métodos , Radioterapia de Intensidade Modulada/efeitos adversos , Suspensão de Tratamento , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma de Células Escamosas/mortalidade , Carcinoma de Células Escamosas/patologia , Feminino , Neoplasias de Cabeça e Pescoço/mortalidade , Neoplasias de Cabeça e Pescoço/patologia , Humanos , Linfonodos/patologia , Linfonodos/efeitos da radiação , Irradiação Linfática/estatística & dados numéricos , Masculino , Pessoa de Meia-Idade , Pescoço , Faringe , Dosagem Radioterapêutica , Radioterapia de Intensidade Modulada/métodos , Estudos Retrospectivos , Carcinoma de Células Escamosas de Cabeça e Pescoço , Carga Tumoral , Adulto Jovem
18.
Dermatol Online J ; 20(10)2014 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-25525999

RESUMO

Pagetoid reticulosis, also known as Woringer-Kolopp disease, is a rare variant of cutaneous T-cell lymphoma usually presenting as an isolated patch or plaque on the extremities. Immunohistochemical staining of T-cell markers can be variable, but as the name implies the epidermotropic lymphocytes consistently display a "pagetoid" appearance. The following case demonstrates clearance of this condition with intensity modulated radiation therapy, whereas most cases are managed with electron beam therapy if radiation therapy is implemented.


Assuntos
Reticulose Pagetoide/radioterapia , Radioterapia de Intensidade Modulada , Neoplasias Cutâneas/radioterapia , Idoso de 80 Anos ou mais , Humanos , Masculino , Reticulose Pagetoide/patologia , Neoplasias Cutâneas/patologia
19.
Med Phys ; 2024 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-39078069

RESUMO

BACKGROUND: Deep learning (DL) techniques have been extensively applied in medical image classification. The unique characteristics of medical imaging data present challenges, including small labeled datasets, severely imbalanced class distribution, and significant variations in imaging quality. Recently, generative adversarial network (GAN)-based classification methods have gained attention for their ability to enhance classification accuracy by incorporating realistic GAN-generated images as data augmentation. However, the performance of these GAN-based methods often relies on high-quality generated images, while large amounts of training data are required to train GAN models to achieve optimal performance. PURPOSE: In this study, we propose an adversarial learning-based classification framework to achieve better classification performance. Innovatively, GAN models are employed as supplementary regularization terms to support classification, aiming to address the challenges described above. METHODS: The proposed classification framework, GAN-DL, consists of a feature extraction network (F-Net), a classifier, and two adversarial networks, specifically a reconstruction network (R-Net) and a discriminator network (D-Net). The F-Net extracts features from input images, and the classifier uses these features for classification tasks. R-Net and D-Net have been designed following the GAN architecture. R-Net employs the extracted feature to reconstruct the original images, while D-Net is tasked with the discrimination between the reconstructed image and the original images. An iterative adversarial learning strategy is designed to guide model training by incorporating multiple network-specific loss functions. These loss functions, serving as supplementary regularization, are automatically derived during the reconstruction process and require no additional data annotation. RESULTS: To verify the model's effectiveness, we performed experiments on two datasets, including a COVID-19 dataset with 13 958 chest x-ray images and an oropharyngeal squamous cell carcinoma (OPSCC) dataset with 3255 positron emission tomography images. Thirteen classic DL-based classification methods were implemented on the same datasets for comparison. Performance metrics included precision, sensitivity, specificity, and F 1 $F_1$ -score. In addition, we conducted ablation studies to assess the effects of various factors on model performance, including the network depth of F-Net, training image size, training dataset size, and loss function design. Our method achieved superior performance than all comparative methods. On the COVID-19 dataset, our method achieved 95.4 % ± 0.6 % $95.4\%\pm 0.6\%$ , 95.3 % ± 0.9 % $95.3\%\pm 0.9\%$ , 97.7 % ± 0.4 % $97.7\%\pm 0.4\%$ , and 95.3 % ± 0.9 % $95.3\%\pm 0.9\%$ in terms of precision, sensitivity, specificity, and F 1 $F_1$ -score, respectively. It achieved 96.2 % ± 0.7 % $96.2\%\pm 0.7\%$ across all these metrics on the OPSCC dataset. The study to investigate the effects of two adversarial networks highlights the crucial role of D-Net in improving model performance. Ablation studies further provide an in-depth understanding of our methodology. CONCLUSION: Our adversarial-based classification framework leverages GAN-based adversarial networks and an iterative adversarial learning strategy to harness supplementary regularization during training. This design significantly enhances classification accuracy and mitigates overfitting issues in medical image datasets. Moreover, its modular design not only demonstrates flexibility but also indicates its potential applicability to various clinical contexts and medical imaging applications.

20.
J Nucl Med ; 65(2): 245-251, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38124163

RESUMO

α-particle emitters are emerging as a potent modality for disseminated cancer therapy because of their high linear energy transfer and localized absorbed dose profile. Despite great interest and pharmaceutical development, there is scant information on the distribution of these agents at the scale of the α-particle pathlength. We sought to determine the distribution of clinically approved [223Ra]RaCl2 in bone metastatic castration-resistant prostate cancer at this resolution, for the first time to our knowledge, to inform activity distribution and dose at the near-cell scale. Methods: Biopsy specimens and blood were collected from 7 patients 24 h after administration. 223Ra activity in each sample was recorded, and the microstructure of biopsy specimens was analyzed by micro-CT. Quantitative autoradiography and histopathology were segmented and registered with an automated procedure. Activity distributions by tissue compartment and dosimetry calculations based on the MIRD formalism were performed. Results: We revealed the activity distribution differences across and within patient samples at the macro- and microscopic scales. Microdistribution analysis confirmed localized high-activity regions in a background of low-activity tissue. We evaluated heterogeneous α-particle emission distribution concentrated at bone-tissue interfaces and calculated spatially nonuniform absorbed-dose profiles. Conclusion: Primary patient data of radiopharmaceutical therapy distribution at the small scale revealed that 223Ra uptake is nonuniform. Dose estimates present both opportunities and challenges to enhance patient outcomes and are a first step toward personalized treatment approaches and improved understanding of α-particle radiopharmaceutical therapies.


Assuntos
Neoplasias Ósseas , Neoplasias da Próstata , Masculino , Humanos , Compostos Radiofarmacêuticos , Neoplasias da Próstata/radioterapia , Neoplasias da Próstata/patologia , Osso e Ossos/diagnóstico por imagem , Osso e Ossos/patologia , Autorradiografia , Neoplasias Ósseas/radioterapia , Neoplasias Ósseas/secundário
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