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1.
Anal Chem ; 95(49): 18020-18028, 2023 12 12.
Artículo en Inglés | MEDLINE | ID: mdl-37991877

RESUMEN

Most of what is known concerning the luminal passage of materials through nanopores arises from electrical measurements. Whether nanopores are biological, solid-state, synthetic, hybrid, glass-capillary-based, or protein ion channels in cells and tissues, characteristic signatures embedded in the flow of ionic current are foundational to understanding functional behavior. In contrast, this work describes passage through a nanopore that occurs without producing an electrical signature. We refer to the phenomenon as "silent translocation." By definition, silent translocations are invisible to the standard tools of electrophysiology and fundamentally require a simultaneous ancillary measurement technique for positive identification. As a result, this phenomenon has been largely unexplored in the literature. Here, we report on a derivative of Cyanine 5 (sCy5a) that passes through the α-hemolysin (αHL) nanopore silently. Simultaneously acquired single-molecule fluorescence and single-channel electrical recordings from bilayers formed over a closed microcavity demonstrate that translocation does indeed take place, albeit infrequently. We report observations of silent translocation as a function of time, dye concentration, and nanopore population in the bilayer. Lastly, measurement of the translocation rate as a function of applied potential permits estimation of an effective energy barrier for transport through the pore as well as the effective charge on the dye, all in the absence of an information-containing electrical signature.


Asunto(s)
Nanoporos , Fluorescencia , Nanotecnología , Electricidad , Transporte Iónico
2.
Ann Surg Oncol ; 29(1): 354-363, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-34114181

RESUMEN

BACKGROUND: Many studies show significantly improved survival after R0 resection compared with R1 resection in pancreatic adenocarcinoma (PAC); however, the effect of neoadjuvant chemoradiation (NACRT) on this association is unknown. OBJECTIVE: The aim of this study was to evaluate the prognostic significance of positive surgical margins (SMs) after NACRT compared with upfront surgery + adjuvant therapy in PAC. METHODS: All cases of surgically resected PAC at a single institution were reviewed from 1996 to 2014; patients treated with palliative intent, metastatic disease, and biliary/ampullary tumors were excluded. The primary endpoint was overall survival (OS). RESULTS: Overall, 300 patients were included; 134 patients received NACRT with concurrent 5-fluorouracil or gemcitabine followed by surgery, and 166 patients received upfront surgery (+ adjuvant chemotherapy in 72% of patients and RT in 65%); 31% of both groups had a positive SM (+SM). The median OS for patients with a +SM or negative SM (-SM) was 26.6 and 31.6 months, respectively for NACRT, and 12.0 and 24.5 months, respectively, for upfront surgery. OS was significantly improved with -SM compared with +SM in both groups (p = 0.006). When resection yielded +SM, NACRT patients had improved OS compared with upfront surgery patients (p < 0.001). On multivariable analysis, +SM in the upfront surgery group (hazard ratio [HR] 2.94, 95% confidence interval [CI] 2.04-4.24; p < 0.001) and older age (HR 1.01, 95% CI 1.00-1.03, per year; p = 0.007) predicted worse OS. +SM in the NACRT group was not associated with worse OS (HR 1.09, 95% CI 0.72-1.65; p = 0.70). CONCLUSION: Patients with a positive margin after NACRT and surgery had longer survival compared with patients with a positive margin after upfront surgery. NACRT should be strongly considered for patients at high risk of R1 resections.


Asunto(s)
Adenocarcinoma , Neoplasias Pancreáticas , Adenocarcinoma/terapia , Anciano , Humanos , Márgenes de Escisión , Terapia Neoadyuvante , Neoplasias Pancreáticas/terapia , Pronóstico
3.
J Surg Res ; 268: 411-418, 2021 12.
Artículo en Inglés | MEDLINE | ID: mdl-34416413

RESUMEN

BACKGROUND: A novel Palladium-103 low-dose rate (LDR) brachytherapy device was developed to provide dose-escalation to the tumor bed after resection while shielding adjacent tissues. This multicenter report describes the initial experience with this device in patients with retroperitoneal sarcoma (RPS). MATERIALS AND METHODS: Patients with recurrent RPS, prior radiotherapy, and/or concern for positive margins were considered. An LDR brachytherapy dose of 20-60 Gy was administered, corresponding to biologically effective dose values of 15-53 Gy and equivalent dose values of 12-43 Gy. RESULTS: Six patients underwent implantation at four institutions. Of these, five had recurrent disease in the retroperitoneum or pelvic sidewall, one had untreated locally advanced leiomyosarcoma, two had prior external beam radiation therapy at the time of initial diagnosis, and four received neoadjuvant external beam radiation therapy plus brachytherapy. The device was easily implanted and conformed to the treatment area. Median follow-up was 16 mo; radiation was delivered to the at-risk margin with minimal irradiation of adjacent structures. No local recurrences at the site of implantation, device migration, or radiation-related toxicities were observed. CONCLUSIONS: The novel LDR directional brachytherapy device successfully delivered a targeted dose escalation to treat RPS high-risk margins. Lack of radiation-related toxicity demonstrates its safety.


Asunto(s)
Braquiterapia , Neoplasias Retroperitoneales , Sarcoma , Braquiterapia/efectos adversos , Humanos , Recurrencia Local de Neoplasia/cirugía , Dosificación Radioterapéutica , Neoplasias Retroperitoneales/radioterapia , Neoplasias Retroperitoneales/cirugía , Estudios Retrospectivos , Sarcoma/radioterapia , Sarcoma/cirugía
4.
Oncologist ; 25(3): e477-e483, 2020 03.
Artículo en Inglés | MEDLINE | ID: mdl-32162826

RESUMEN

BACKGROUND: Several registry-based analyses suggested a survival advantage for married versus single patients with pancreatic cancer. The mechanisms underlying the association of marital status and survival are likely multiple and complex and, therefore, may be obscured in analyses generated from large population-based databases. The goal of this research was to characterize this potential association of marital status with outcomes in patients with resected pancreatic cancer who underwent combined modality adjuvant therapy on a prospective clinical trial. MATERIALS AND METHODS: This is an ancillary analysis of 367 patients with known marital status treated on NRG Oncology/RTOG 97-04. Survival analysis was performed using the Kaplan-Meier method and compared using the log-rank test. Multivariate analysis was performed using the Cox proportional hazards regression model. RESULTS: Of 367 patients, 271 (74%) were married or partnered and 96 (26%) were single. Married or partnered patients were more likely to be male. There was no association between marital status and overall survival (OS) or disease-free survival (DFS) on univariate (hazard ratio [HR], 1.09 and 1.01, respectively) or multivariate analyses (HR, 1.05 and 0.98, respectively). Married or partnered male patients did not have improved survival compared with female or single patients. CONCLUSION: Ancillary analysis of data from NRG Oncology/RTOG 97-04 demonstrated no association between marital and/or partner status and OS or DFS in patients with resected pancreatic cancer who received adjuvant postoperative chemotherapy followed by concurrent external beam radiation therapy and chemotherapy. Clinical trial identification number. NCT00003216. IMPLICATIONS FOR PRACTICE: Several population-based studies have shown an epidemiological link between marital status and survival in patients with pancreatic cancer. A better understanding of this association could offer an opportunity to improve outcomes through psychosocial interventions designed to mitigate the negative effects of not being married. Based on the results of this analysis, patients who have undergone a resection and are receiving adjuvant therapy on a clinical trial are unlikely to benefit from such interventions. Further efforts to study the association between marital status and survival should be focused on less selected subgroups of patients with pancreatic cancer.


Asunto(s)
Neoplasias Pancreáticas , Femenino , Humanos , Masculino , Estado Civil , Neoplasias Pancreáticas/tratamiento farmacológico , Neoplasias Pancreáticas/cirugía , Modelos de Riesgos Proporcionales , Estudios Prospectivos , Análisis de Supervivencia
5.
J Surg Res ; 243: 242-248, 2019 11.
Artículo en Inglés | MEDLINE | ID: mdl-31229791

RESUMEN

BACKGROUND: A major challenge in identifying candidates for nonoperative management of locally advanced rectal cancer is predicting pathologic complete response (pCR) following chemoradiation. We evaluated pre- and post-CRT PET-CT imaging to predict pCR and prognosis in this set of patients undergoing resection after neoadjuvant therapy. METHODS: We retrospectively identified patients from 2002 to 2015 with locally advanced rectal cancer who underwent CRT, pre- and post-CRT PET-CT imaging, and resection. Univariate and multivariate analysis was performed and receiver operating characteristic (ROC) curves were generated to evaluate the association of PET-CT characteristics with pCR and survival. ROC curves were generated to define optimal cutoff points for predictive PET-CT characteristics. RESULTS: 125 patients were included. pCR rate was 28%, and follow-up was 48 mo. On multivariable analysis, patients who had a pCR had lower median post-CRT maximal standardized uptake value (SUVmax) (3.2 versus 5.2, P = 0.009) and higher median %SUV decrease (72 versus 58%, P = 0.009). ROC curves were generated for %SUVmax decrease (AUC = 0.70) and post-CRT SUV (AUC = 0.69). Post-CRT SUVmax <4.3 and %SUVmax decrease of >66% were equally predictive of pCR with a sensitivity of 65%, specificity of 72%, PPV of 44%, and NPV of 86%. Median 5-y overall and relapse-free survival were improved for patients with post-CRT SUV <4.3 (OS: 86 versus 66%, P = 0.01; RFS: 75 versus 52%, P = 0.01) or %SUV decrease of >66% (OS, 82 versus 66%, P = 0.05; RFS, 75 versus 54%, P = 0.01). CONCLUSIONS: PET/CT may be useful in identifying patients who did not achieve pCR, as well as overall survival in patients undergoing CRT for rectal cancer. Patients with a post-CRT SUV of >4.3 should be considered for operative management, as an estimated 86% of these patients will not have a pCR.


Asunto(s)
Adenocarcinoma/diagnóstico por imagen , Recurrencia Local de Neoplasia/diagnóstico por imagen , Tomografía Computarizada por Tomografía de Emisión de Positrones , Neoplasias del Recto/diagnóstico por imagen , Adenocarcinoma/mortalidad , Adenocarcinoma/terapia , Adulto , Anciano , Anciano de 80 o más Años , Quimioradioterapia , Femenino , Humanos , Masculino , Persona de Mediana Edad , Terapia Neoadyuvante , Estadificación de Neoplasias , Philadelphia/epidemiología , Neoplasias del Recto/mortalidad , Neoplasias del Recto/terapia , Estudios Retrospectivos
6.
J Surg Res ; 232: 275-282, 2018 12.
Artículo en Inglés | MEDLINE | ID: mdl-30463730

RESUMEN

BACKGROUND: Advances in treatment of rectal cancer have improved survival, but there is variability in response to therapy. Recent data suggest the utility of the lymphocyte-to-monocyte ratio (LMR), neutrophil-to-lymphocyte ratio (NLR), and platelet-to-lymphocyte ratio (PLR) in predicting survival. Our aim was to examine these ratios in rectal cancer patients and determine whether any association exists with overall survival (OS). METHODS: Using prospectively maintained institutional data, a query was completed for clinical stage II-III rectal adenocarcinoma patients treated from 2002 to 2016. We included patients who had a complete blood count collected before neoadjuvant chemoradiation (pre-CRT) and again before surgery (post-CRT). The LMR, NLR, and PLR were calculated for the pre-CRT and post-CRT time points. Potential cutpoints associated with OS differences were determined using maximally selected rank statistics. Survival curves were compared using log-rank tests and were adjusted for age and stage using Cox regression. RESULTS: A total of 146 patients were included. Cutpoints were significantly associated with OS for pre-CRT ratios but not for post-CRT ratios. Within the pretreatment group, a "low" (<2.86) LMR was associated with decreased OS (log-rank P = 0.004). In the same group, a "high" (>4.47) NLR and "high" PLR (>203.6) were associated with decreased OS (log-rank P < 0.001). With covariate adjustment for age, and separately for final pathologic stage, the associations between OS and LMR, NLR, and PLR each retained statistical significance. CONCLUSIONS: If obtained before the start of neoadjuvant chemoradiation, LMR, NLR, and PLR values are accurate predictors of 5-y OS in patients with locally advanced rectal adenocarcinoma.


Asunto(s)
Adenocarcinoma/sangre , Plaquetas , Leucocitos , Neoplasias del Recto/sangre , Adenocarcinoma/mortalidad , Adenocarcinoma/terapia , Adulto , Anciano , Anciano de 80 o más Años , Quimioradioterapia , Femenino , Humanos , Linfocitos , Masculino , Persona de Mediana Edad , Monocitos , Neutrófilos , Neoplasias del Recto/mortalidad , Neoplasias del Recto/terapia
8.
Breast J ; 23(2): 169-176, 2017 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-27797159

RESUMEN

Although standard practice guidelines for breast cancer are clear, the interplay between insurance and practice patterns for the US is poorly defined. This study was performed to test for associations between patient insurance status and presentation of breast cancer as well as local therapy patterns in the US, via a large national dataset. We queried the NCI Surveillance, Epidemiology, and End Results data base for breast cancer cases diagnosed from 2007 to 2011 in women aged 18-64 with nonmetastatic ductal/lobular cancers, treated surgically. We tested for associations between insurance status (insured/Medicaid/uninsured) and choice of surgical procedure (mastectomy/breast conserving surgery [BCS]), omission of radiotherapy (RT) following BCS, and administration of post-mastectomy radiation (PMRT). There were 129,565 patients with localized breast cancer analyzed. The health insurance classification included insured (84.5%), Medicaid (11.5%), uninsured (2.1%) and unknown (1.9%). Medicaid or uninsured status was associated with large, node positive tumors, black race, and low income. The BCS rate varied by insurance status: insured (52.2%), uninsured (47.7%), and Medicaid (45.2%), p < 0.001. In multivariable analysis, Medicaid insurance remained significantly associated with receipt of mastectomy (OR [95% CI] = 1.07 [1.03-1.11]), while RT was more frequently omitted after BCS in both Medicaid (OR [95% CI] = 1.14 [1.07-1.21]) and uninsured (OR [95% CI] = 1.29 [1.14-1.47]) patients. Insurance status was associated with significant variations in breast cancer care in the US. Although patient choice cannot be determined from this dataset, departure from standard of care is associated with specific types of insurance coverage. Further investigation into the reasons for these departures is strongly suggested.


Asunto(s)
Neoplasias de la Mama/terapia , Disparidades en Atención de Salud , Cobertura del Seguro , Adolescente , Adulto , Neoplasias de la Mama/cirugía , Femenino , Humanos , Seguro de Salud , Mastectomía Segmentaria/estadística & datos numéricos , Medicaid , Pacientes no Asegurados , Persona de Mediana Edad , Sistema de Registros , Programa de VERF , Estados Unidos , Adulto Joven
9.
Cancer ; 122(9): 1349-69, 2016 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-26799932

RESUMEN

Cholangiocarcinomas are rare biliary tract tumors that are often challenging to diagnose and treat. Cholangiocarcinomas are generally categorized as intrahepatic or extrahepatic depending on their anatomic location. The majority of patients with cholangiocarcinoma do not have any of the known or suspected risk factors and present with advanced disease. The optimal evaluation and management of patients with cholangiocarcinoma requires thoughtful integration of clinical information, imaging studies, cytology and/or histology, as well as prompt multidisciplinary evaluation. The current review focuses on recent advances in the diagnosis and treatment of patients with cholangiocarcinoma and, in particular, on the role of endoscopy, surgery, transplantation, radiotherapy, systemic therapy, and liver-directed therapies in the curative or palliative treatment of these individuals. Cancer 2016;122:1349-1369. © 2016 American Cancer Society.


Asunto(s)
Neoplasias de los Conductos Biliares/diagnóstico , Neoplasias de los Conductos Biliares/terapia , Conductos Biliares Intrahepáticos , Colangiocarcinoma/diagnóstico , Colangiocarcinoma/terapia , Neoplasias de los Conductos Biliares/etiología , Biomarcadores de Tumor/sangre , Colangiocarcinoma/etiología , Diagnóstico por Imagen/métodos , Endosonografía/métodos , Humanos , Estadificación de Neoplasias , Factores de Riesgo
10.
Acta Oncol ; 55(3): 303-8, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-26581671

RESUMEN

BACKGROUND: Although tri-modality therapy is an acceptable standard of care in patients with locally advanced esophageal cancer, data regarding patterns of failure is lacking. We report bi-institutional patterns of failure experience treating patients using tri-modality therapy. MATERIALS AND METHODS: We retrospectively reviewed patients who underwent chemoradiation followed by esophagectomy between 2006 and 2011 at two NCI-designated cancer centers. First failure sites were categorized as local, regional nodal, or distant. Statistical analysis was performed using Fisher's exact test, non-parametric Wilcoxon rank-sum test, and multiple logistic regression. Kaplan-Meier curves were generated for relapse-free survival (RFS) and overall survival. RESULTS: A total of 132 patients met the inclusion criteria with a median age of 62 (range 36-80) and median follow-up of 28 months (range 4-128). There were a total of six (4.5%) local, 13 (10%) regional nodal, and 32 (23.5%) distant failures. Local failure was correlated with fewer lymph nodes (LN) assessed (p = 0.01) and close/positive margins (p < 0.01). Regional nodal failure was correlated with fewer LN assessed (p < 0.01) and larger pretreatment tumor size (p = 0.04). Patients with ≤13 LN evaluated had an inferior locoregional RFS versus patients with >13 LN evaluated (p = 0.003). Distant recurrence was correlated with higher pathologic nodal stage (p < 0.001), ulceration (p = 0.017), perineural invasion (p = 0.029), residual disease (p = 0.004), and higher post-treatment PET SUV max (p = 0.049). Patients with a pathologic complete response (OR 0.19, 95% CI 0.05-0.68) were less likely to experience distant recurrence. CONCLUSION: Tumor and treatment factors may predict for failure in patients undergoing tri-modality therapy for locally advanced esophageal cancer. Further data is needed to identify patterns of failure in these patients.


Asunto(s)
Adenocarcinoma/terapia , Carcinoma de Células Escamosas/terapia , Neoplasias Esofágicas/terapia , Recurrencia Local de Neoplasia/terapia , Neoplasia Residual/terapia , Adenocarcinoma/patología , Adulto , Anciano , Anciano de 80 o más Años , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Carcinoma de Células Escamosas/patología , Quimioradioterapia , Terapia Combinada , Neoplasias Esofágicas/patología , Esofagectomía , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Invasividad Neoplásica , Recurrencia Local de Neoplasia/patología , Estadificación de Neoplasias , Neoplasia Residual/patología , Estudios Retrospectivos , Tasa de Supervivencia , Insuficiencia del Tratamiento
12.
J Surg Oncol ; 112(6): 629-33, 2015 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-26430952

RESUMEN

BACKGROUND AND OBJECTIVES: To identify the impact of the interval between chemoradiation to surgery on morbidity and mortality in patients undergoing tri-modality therapy for esophageal cancer. METHODS: Eighty-five patients completed chemoradiation followed by esophagectomy between 2006 and 2011. The interval between completion of chemoradiation and surgery was calculated for each patient. We evaluated the association of quartiles and 3-week groups with morbidity and mortality using logistic regression. Other treatment and clinical factors were also assessed. RESULTS: A total of 59 patients(69%) experienced at least one complication. When examining specific complications, patients with pulmonary complications had a longer mean time interval from chemoradiation to surgery (P = 0.02). Linear regression showed an association between longer interval between chemoradiation to surgery and hospital length of stay (LOS) >14 days when analyzing by both interval quartile (P = 0.04) and 3-week intervals (P = 0.04). On multivariable analysis, increased time interval predicted for pulmonary complications (P < 0.01) and LOS >14 days (P = 0.03). When examining other treatment factors, squamous cell histology (P = 0.02) also predicted for a hospital length of stay >14 days. CONCLUSIONS: Factors such as interval between completion of chemoradiation and surgery and squamous cell histology may be associated with surgical morbidity. Further data is warranted to confirm these findings.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Neoplasias Esofágicas/patología , Neoplasias Esofágicas/terapia , Esofagectomía , Tiempo de Internación , Morbilidad , Complicaciones Posoperatorias , Adenocarcinoma/patología , Adenocarcinoma/terapia , Adulto , Anciano , Anciano de 80 o más Años , Carcinoma de Células Escamosas/patología , Carcinoma de Células Escamosas/terapia , Quimioradioterapia , Terapia Combinada , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Terapia Neoadyuvante , Estadificación de Neoplasias , Pronóstico , Estudios Retrospectivos , Factores de Tiempo
13.
Ann Surg Oncol ; 21(2): 662-9, 2014 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-24276638

RESUMEN

BACKGROUND: Neoadjuvant chemoradiation and chemotherapy provided for borderline or locally advanced, potentially resectable pancreatic adenocarcinoma improves resectability rates. Response to therapy is also an important prognostic factor. There are no data in the literature regarding optimal time interval or duration of chemotherapy after chemoradiation before surgery, and pathologic response rates. Using our database, we evaluated these relationships and the effect on overall and progression-free survival. METHODS: We retrospectively analyzed the records of 83 patients who underwent neoadjuvant chemoradiation for locally advanced, potentially resectable, and borderline resectable pancreatic cancers before definitive resection. We divided patients into three groups according to time interval between completion of chemoradiation and resection: group A (0-10 weeks), group B (11-20 weeks), and group C (>20 weeks). After chemoradiation, patients underwent ongoing chemotherapy before resection. Pathologic response was defined as major (>95% fibrosis), partial (50-94% fibrosis), or minor (<50% fibrosis). RESULTS: There were 56 patients in group A, 17 patients in group B, and 10 patients in group C. Patients in groups B and C were significantly more likely to experience a major response than group A (p < 0.013). Patients in group C had significantly increased median progression-free and overall survival (p < 0.05). Multivariable classification and regression tree analysis demonstrated pathologic response to be the only significant factor in overall survival. CONCLUSIONS: Patients who underwent a prolonged time interval after neoadjuvant chemoradiation with ongoing chemotherapy were more likely to have an improved pathologic response at time of surgical resection, which was associated with improved median overall survival.


Asunto(s)
Adenocarcinoma/terapia , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Quimioradioterapia , Terapia Neoadyuvante , Neoplasias Pancreáticas/terapia , Adenocarcinoma/mortalidad , Adenocarcinoma/patología , Adulto , Anciano , Anciano de 80 o más Años , Capecitabina , Quimioterapia Adyuvante , Desoxicitidina/administración & dosificación , Desoxicitidina/análogos & derivados , Femenino , Fluorouracilo/administración & dosificación , Fluorouracilo/análogos & derivados , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Estadificación de Neoplasias , Neoplasias Pancreáticas/mortalidad , Neoplasias Pancreáticas/patología , Cuidados Preoperatorios , Pronóstico , Radioterapia Adyuvante , Estudios Retrospectivos , Tasa de Supervivencia , Factores de Tiempo , Gemcitabina
14.
HPB (Oxford) ; 16(1): 34-9, 2014 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-23458131

RESUMEN

BACKGROUND: A theoretical advantage of preoperative therapy in pancreatic adenocarcinoma is that it facilitates the early treatment of micrometastases and reduces postoperative systemic recurrence. METHODS: Medical records of 309 consecutive patients undergoing resection of adenocarcinoma in the head of the pancreas were reviewed. Survival was calculated using the Kaplan-Meier method. Associations between preoperative therapy and patterns of recurrence were determined using chi-squared analysis. RESULTS: Preoperative therapy was administered to 108 patients and upfront surgery was performed in 201 patients. Preoperative therapy was associated with a significantly longer median disease-free survival of 14 months compared with 12 months in patients submitted to upfront surgery (P = 0.035). The rate of local disease as a component of first site of recurrence was significantly lower with preoperative therapy (11.3%) than with upfront surgery (22.9%) (P = 0.016). Preoperative therapy was associated with a lower rate of hepatic metastasis (21.7%) than upfront surgery (34.3%) (P = 0.026). Preoperative therapy did not affect rates of peritoneal or pulmonary metastasis. CONCLUSIONS: Preoperative therapy for pancreatic cancer was associated with longer disease-free survival and lower rates of local and hepatic recurrences. These data support the use of preoperative therapy to reduce systemic and local failures after resection.


Asunto(s)
Adenocarcinoma/terapia , Terapia Neoadyuvante , Recurrencia Local de Neoplasia , Pancreatectomía , Neoplasias Pancreáticas/terapia , Adenocarcinoma/mortalidad , Adenocarcinoma/secundario , Adenocarcinoma/cirugía , Adulto , Anciano , Anciano de 80 o más Años , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Quimioradioterapia Adyuvante , Quimioterapia Adyuvante , Distribución de Chi-Cuadrado , Supervivencia sin Enfermedad , Femenino , Humanos , Estimación de Kaplan-Meier , Neoplasias Hepáticas/prevención & control , Neoplasias Hepáticas/secundario , Neoplasias Pulmonares/prevención & control , Neoplasias Pulmonares/secundario , Masculino , Persona de Mediana Edad , Terapia Neoadyuvante/efectos adversos , Terapia Neoadyuvante/mortalidad , Micrometástasis de Neoplasia , Pancreatectomía/efectos adversos , Pancreatectomía/mortalidad , Neoplasias Pancreáticas/mortalidad , Neoplasias Pancreáticas/patología , Neoplasias Pancreáticas/cirugía , Neoplasias Peritoneales/prevención & control , Neoplasias Peritoneales/secundario , Estudios Retrospectivos , Factores de Riesgo , Factores de Tiempo , Resultado del Tratamiento
15.
Adv Radiat Oncol ; 9(4): 101412, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38778829

RESUMEN

Purpose: Conventional chemoradiation (CCRT) is inadequately effective for the treatment of unresectable or inoperable biliary tract cancers (UIBC). Ablative radiation therapy (AR), typically defined as a biologically effective dose (BED) ≥80.5 Gy, has shown some promise in terms of local control and survival in these patients. We compare the efficacy and toxicity of AR to non-AR in UIBC patients. Methods and Materials: Patients with UIBC treated with stereotactic body radiation therapy (SBRT; n = 18) or CCRT (n = 28) between 2006 and 2021 were retrospectively analyzed. The associations of treatment, BED groups, selected characteristics with overall survival (OS), progression-free survival (PFS), and local control were estimated separately using Cox proportional hazards regression. Toxicity was scored using Common Terminology Criteria for Adverse Events (CTCAE) version 5.0. Results: Median dose fractionation was 60 Gy in 5 fractions (median BED, 127 Gy) for SBRT and 50 Gy in 25 fractions (median BED, 64 Gy) for CCRT. The median follow-up of the entire cohort was 11.5 months. The 1-year OS rate was 62% for BED <80.5 versus 66% for BED ≥80.5 (P = .069). The 1-year PFS rate was 24% for BED <80.5 and 29% for BED ≥80.5 (P = .050). The 1-year local control rate was 20% for BED <80.5 and 41% for BED ≥80.5 (P = .097). BED as a continuous variable (P = .013), BED ≥100 Gy (P = .044), and race (white versus nonwhite) (P = .037) were associated with improved overall mortality. BED ≥80.5 Gy (P = .046), smaller tumor size (<5 cm; P = .038) and N0 disease (P <.0001) were associated with improved disease progression rates. Local control was improved in patients with N0 disease compared with N1 disease (P <.0001). Both treatments were well tolerated; there was no difference in acute and late toxicity between AR and non-AR. Conclusions: In this review, there was improved PFS with BED ≥80.5 Gy with a trend toward OS benefit. BED ≥80.5 Gy was achieved mostly through SBRT and was well tolerated. AR could be considered a more effective treatment modality than CCRT in patients with UIBC.

16.
JAMA Netw Open ; 7(2): e240044, 2024 Feb 05.
Artículo en Inglés | MEDLINE | ID: mdl-38421650

RESUMEN

Importance: Hispanic and non-Hispanic Black patients receiving neoadjuvant therapy and surgery for locally advanced rectal cancer (LARC) achieve less favorable clinical outcomes than non-Hispanic White patients, but the source of this disparity is incompletely understood. Objective: To assess whether racial and ethnic disparities in treatment outcomes among patients with LARC could be accounted for by social determinants of health and demographic, clinical, and pathologic factors known to be associated with treatment response. Design, Setting, and Participants: The National Cancer Database was interrogated to identify patients with T3 to T4 or N1 to N2 LARC treated with neoadjuvant therapy and surgery. Patients were diagnosed between January 1, 2004, and December 31, 2017. Data were culled from the National Cancer Database from July 1, 2022, through December 31, 2023. Exposure: Neoadjuvant therapy for rectal cancer followed by surgical resection. Main Outcomes and Measures: The primary outcome was the rate of pathologic complete response (pCR) following neoadjuvant therapy. Secondary outcomes were rate of tumor downstaging and achievement of pN0 status. Results: A total of 34 500 patient records were reviewed; 21 679 of the patients (62.8%) were men and 12 821 (37.2%) were women. The mean (SD) age at diagnosis was 59.7 (12.0) years. In terms of race and ethnicity, 2217 patients (6.4%) were Hispanic, 2843 (8.2%) were non-Hispanic Black, and 29 440 (85.3%) were non-Hispanic White. Hispanic patients achieved tumor downstaging (48.9% vs 51.8%; P = .01) and pN0 status (66.8% vs 68.8%; P = .02) less often than non-Hispanic White patients. Non-Hispanic Black race, but not Hispanic ethnicity, was associated with less tumor downstaging (odds ratio [OR], 0.86 [95% CI, 0.78-0.94]), less frequent pN0 status (OR, 0.91 [95% CI, 0.83-0.99]), and less frequent pCR (OR, 0.81 [95% CI, 0.72-0.92]). Other factors associated with reduced rate of pCR included rural location (OR, 0.80 [95% CI, 0.69-0.93]), lack of or inadequate insurance (OR for Medicaid, 0.86 [95% CI, 0.76-0.98]; OR for no insurance, 0.65 [95% CI, 0.54-0.78]), and treatment in a low-volume center (OR for first quartile, 0.73 [95% CI, 0.62-0.87]; OR for second quartile, 0.79 [95% CI, 0.70-0.90]; OR for third quartile, 0.86 [95% CI, 0.78-0.94]). Clinical and pathologic variables associated with a decreased pCR included higher tumor grade (OR, 0.58 [95% CI, 0.49-0.70]), advanced tumor stage (OR for T3, 0.56 [95% CI, 0.42-0.76]; OR for T4, 0.30 [95% CI, 0.22-0.42]), and lymph node-positive disease (OR for N1, 0.83 [95% CI, 0.77-0.89]; OR for N2, 0.73 [95% CI, 0.65-0.82]). Conclusions and Relevance: The findings of this cohort study suggest that disparate treatment outcomes for Hispanic and non-Hispanic Black patients are likely multifactorial in origin. Future investigation into additional social determinants of health and biological variables is warranted.


Asunto(s)
Disparidades en el Estado de Salud , Neoplasias del Recto , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios de Cohortes , Etnicidad , Hispánicos o Latinos , Neoplasias del Recto/terapia , Estados Unidos/epidemiología , Negro o Afroamericano , Determinantes Sociales de la Salud , Grupos Raciales , Anciano
17.
ACS Appl Bio Mater ; 7(3): 1936-1946, 2024 03 18.
Artículo en Inglés | MEDLINE | ID: mdl-38427377

RESUMEN

Artificial lipid bilayers have revolutionized biochemical and biophysical research by providing a versatile interface to study aspects of cell membranes and membrane-bound processes in a controlled environment. Artificial bilayers also play a central role in numerous biosensing applications, form the foundational interface for liposomal drug delivery, and provide a vital structure for the development of synthetic cells. But unlike the envelope in many living cells, artificial bilayers can be mechanically fragile. Here, we develop prototype scaffolds for artificial bilayers made from multiple chemically linked tiers of actin filaments that can be bonded to lipid headgroups. We call the interlinked and layered assembly a multiple minimal actin cortex (multi-MAC). Construction of multi-MACs has the potential to significantly increase the bilayer's resistance to applied stress while retaining many desirable physical and chemical properties that are characteristic of lipid bilayers. Furthermore, the linking chemistry of multi-MACs is generalizable and can be applied almost anywhere lipid bilayers are important. This work describes a filament-by-filament approach to multi-MAC assembly that produces distinct 2D and 3D architectures. The nature of the structure depends on a combination of the underlying chemical conditions. Using fluorescence imaging techniques in model planar bilayers, we explore how multi-MACs vary with electrostatic charge, assembly time, ionic strength, and type of chemical linker. We also assess how the presence of a multi-MAC alters the underlying lateral diffusion of lipids and investigate the ability of multi-MACs to withstand exposure to shear stress.


Asunto(s)
Actinas , Membrana Dobles de Lípidos , Membrana Celular , Citoesqueleto , Citoesqueleto de Actina
18.
bioRxiv ; 2024 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-38293200

RESUMEN

Pancreatic cancer is becoming increasingly deadly, with treatment options limited due to, among others, the complex tumor microenvironment (TME). This short communications study investigates pulsed low-dose-rate radiation (PLDR) as a potential alternative to conventional radiotherapy for pancreatic cancer neoadjuvant treatment. Our ex vivo research demonstrates that PLDR, in combination with chemotherapy, promotes a shift from tumor-promoting to tumor-suppressing properties in a key component of the pancreatic cancer microenvironment we called CAFu (cancer-associated fibroblasts and selfgenerated extracellular matrix functional units). This beneficial effect translates to reduced desmoplasia (fibrous tumor expansion) and suggests PLDR's potential to improve total neoadjuvant therapy effectiveness. To comprehensively assess this functional shift, we developed the HOST-Factor, a single score integrating multiple biomarkers. This tool provides a more accurate picture of CAFu function compared to individual biomarkers and could be valuable for guiding and monitoring future therapeutic strategies. Our findings support the ongoing NCT04452357 clinical trial testing PLDR safety and TME normalization potential in pancreatic cancer patients. The HOST-Factor will be used in samples collected from this trial to validate its potential as a key tool for personalized medicine in this aggressive disease.

19.
Anal Chem ; 85(15): 7159-66, 2013 Aug 06.
Artículo en Inglés | MEDLINE | ID: mdl-23848566

RESUMEN

Scanning electrochemical microscopy was used to probe the topography and electrochemical activity of CoCrMo alloys mechanically polished in the presence of bovine calf serum (BCS) in a hip simulator. These substrates are made of the same alloy used in metal-on-metal bearings for artificial hip joints. The BCS serves as an in vitro substitute for the synovial fluid which forms a lubricant in the actual orthopedic device. Chemical and mechanical processes result in the formation of a tribolayer which passivates the alloy surface. Our studies of the heterogeneous electron transfer between ferrocenemethanol and the alloy indicate that the tribolayer formed on both high- and low-carbon substrates is highly heterogeneous with regions of high electrochemical activity. Whereas pits in the samples polished in the absence of BCS show the regions of highest electrochemical activity, the tribolayer-coated samples have electrochemical hot spots in topographically smooth regions of the surface. The tribolayer provides some attenuation of the electrochemical activity of the alloy but does not prevent the possibility of corrosion from occurring.


Asunto(s)
Aleaciones/química , Cromo/química , Cobalto/química , Microscopía Electroquímica de Rastreo , Molibdeno/química , Animales , Bovinos , Corrosión , Electroquímica
20.
Nutrients ; 15(9)2023 Apr 23.
Artículo en Inglés | MEDLINE | ID: mdl-37432170

RESUMEN

Many cancers are associated with poor diet, lack of physical activity, and excess weight. Improving any of these three lifestyle factors would likely reduce cancer deaths. However, modifications to each of these-better nutrition, enhanced activity and fitness, and loss of extra body fat-have different effect sizes on cancer mortality. This review will highlight the relative benefit that each lifestyle change, enacted prior to a diagnosis of cancer, might impart on cancer-related deaths, as well as attempt to quantify the changes required to derive such a benefit. The review relies primarily on epidemiological data, with meta-analyses serving as the backbone for comparisons across interventions and individual studies within the larger meta-analyses providing the data necessary to form more quantitative conclusions. The reader can then use this information to better understand, recommend, and implement behaviors that might ultimately reduce cancer mortality. Of all the interventions, it seems clear that exercise, specifically improving cardiorespiratory fitness, is the best way to decrease the risk of dying from cancer.


Asunto(s)
Capacidad Cardiovascular , Neoplasias , Terapia Conductista , Tejido Adiposo , Ejercicio Físico , Estado Nutricional , Neoplasias/prevención & control
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