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1.
Glob Chang Biol ; 30(5): e17287, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38695768

RESUMEN

While droughts predominantly induce immediate reductions in plant carbon uptake, they can also exert long-lasting effects on carbon fluxes through associated changes in leaf area, soil carbon, etc. Among other mechanisms, shifts in carbon allocation due to water stress can contribute to the legacy effects of drought on carbon fluxes. However, the magnitude and impact of these allocation shifts on carbon fluxes and pools remain poorly understood. Using data from a wet tropical flux tower site in French Guiana, we demonstrate that drought-induced carbon allocation shifts can be reliably inferred by assimilating Net Biosphere Exchange (NBE) and other observations within the CARbon DAta MOdel fraMework. This model-data fusion system allows inference of optimized carbon and water cycle parameters and states from multiple observational data streams. We then examined how these inferred shifts affected the duration and magnitude of drought's impact on NBE during and after the extreme event. Compared to a static allocation scheme analogous to those typically implemented in land surface models, dynamic allocation reduced average carbon uptake during drought recovery by a factor of 2.8. Additionally, the dynamic model extended the average recovery time by 5 months. The inferred allocation shifts influenced the post-drought period by altering foliage and fine root pools, which in turn modulated gross primary productivity and heterotrophic respiration for up to a decade. These changes can create a bust-boom cycle where carbon uptake is enhanced some years after a drought, compared to what would have occurred under drought-free conditions. Overall, allocation shifts accounted for 65% [45%-75%] of drought legacy effects in modeled NBE. In summary, drought-induced carbon allocation shifts can play a substantial role in the enduring influence of drought on cumulative land-atmosphere CO2 exchanges and should be accounted for in ecosystem models.


Asunto(s)
Ciclo del Carbono , Sequías , Clima Tropical , Guyana Francesa , Bosques , Carbono/metabolismo , Modelos Teóricos
2.
Radiol Med ; 120(10): 959-66, 2015 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-25725789

RESUMEN

PURPOSE: The aim of this study was to systematically compare a comprehensive array of magnetic resonance (MR) imaging features in terms of their sensitivity and specificity to diagnose cervical lymph node metastases in patients with thyroid cancer. MATERIALS AND METHODS: The study included 41 patients with thyroid malignancy who underwent surgical excision of cervical lymph nodes and had preoperative MR imaging ≤4weeks prior to surgery. Three head and neck neuroradiologists independently evaluated all the MR images. Using the pathology results as reference, the sensitivity, specificity and interobserver agreement of each MR imaging characteristic were calculated. RESULTS: On multivariate analysis, no single imaging feature was significantly correlated with metastasis. In general, imaging features demonstrated high specificity, but poor sensitivity and moderate interobserver agreement at best. CONCLUSIONS: Commonly used MR imaging features have limited sensitivity at correctly identifying cervical lymph node metastases in patients with thyroid cancer. A negative neck MR scan should not dissuade a surgeon from performing a neck dissection in patients with thyroid carcinomas.


Asunto(s)
Metástasis Linfática/patología , Imagen por Resonancia Magnética , Neoplasias de la Tiroides/patología , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Masculino , Persona de Mediana Edad , Cuello , Reproducibilidad de los Resultados , Estudios Retrospectivos , Sensibilidad y Especificidad , Adulto Joven
3.
Am J Otolaryngol ; 35(2): 137-40, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-24315629

RESUMEN

PURPOSE: To determine the utility of abdominal imaging to further evaluate abnormal pre-operative liver function tests (LFTs) in patients with head and neck squamous cell carcinoma (HNSCC). METHODS: Records of patients evaluated by the head and neck surgery service from January 2004 through December 2009 were reviewed. For patients with abnormal alkaline phosphatase, alanine transaminase, or aspartate transaminase, subsequent abdominal imaging was assessed. RESULTS: Of the 862 patients with HNSCC who had documented LFTs, 109 (12.6%) had one or more abnormal values. In the same time period, LFTs were also obtained on 361 patients with benign head and neck tumors; of these, 40 (11.1%) had abnormalities. Of the 109 patients with HNSCC and abnormal LFTs, 78 (71.6%) underwent abdominal imaging (ultrasound, CT, MRI, or PET/CT). Overall, liver metastasis was demonstrated in only 1 of 109 patients with abnormal LFTs (0.92%) and in only 1 of 862 patients with HNSCC (0.12%). CONCLUSIONS: While HNSCC patients rarely present with liver metastasis, they often have abnormal LFTs. Although the presence of liver metastasis can dramatically change patient management, the yield of follow-up liver imaging for all patients with elevated LFTs is exceedingly low. Thus, the use of risk-stratified abdominal imaging may be prudent and cost effective in a select group of patients in whom distant metastasis is more likely. However, characteristics of this group are difficult to define given the rarity of liver metastasis in HNSCC.


Asunto(s)
Alanina Transaminasa/sangre , Fosfatasa Alcalina/sangre , Aspartato Aminotransferasas/sangre , Carcinoma de Células Escamosas/secundario , Diagnóstico por Imagen/estadística & datos numéricos , Neoplasias de Cabeza y Cuello/secundario , Neoplasias Hepáticas/diagnóstico , Abdomen/diagnóstico por imagen , Abdomen/patología , Biomarcadores de Tumor/sangre , Carcinoma de Células Escamosas/sangre , Carcinoma de Células Escamosas/diagnóstico , Diagnóstico por Imagen/métodos , Estudios de Seguimiento , Neoplasias de Cabeza y Cuello/sangre , Neoplasias de Cabeza y Cuello/diagnóstico , Humanos , Pruebas de Función Hepática , Neoplasias Hepáticas/enzimología , Neoplasias Hepáticas/secundario , Imagen por Resonancia Magnética , Metástasis de la Neoplasia , Tomografía de Emisión de Positrones , Pronóstico , Reproducibilidad de los Resultados , Estudios Retrospectivos , Carcinoma de Células Escamosas de Cabeza y Cuello , Tomografía Computarizada por Rayos X , Ultrasonografía
4.
Nat Clim Chang ; 11: 143-151, 2021 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-34163539

RESUMEN

Future changes in the position of the intertropical convergence zone (ITCZ; a narrow band of heavy precipitation in the tropics) with climate change could affect the livelihood and food security of billions of people. Although models predict a future narrowing of the ITCZ, uncertainties remain large regarding its future position, with most past work focusing on zonal-mean shifts. Here we use projections from 27 state-of-the-art (CMIP6) climate models and document a robust zonally-varying ITCZ response to the SSP3-7.0 scenario by 2100, with a northward shift over eastern Africa and the Indian Ocean, and a southward shift in the eastern Pacific and Atlantic Oceans. The zonally-varying response is consistent with changes in the divergent atmospheric energy transport, and sector-mean shifts of the energy flux equator. Our analysis provides insight about mechanisms influencing the future position of the tropical rainbelt, and may allow for more robust projections of climate change impacts.

5.
Am J Clin Pathol ; 130(2): 213-8, 2008 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-18628089

RESUMEN

Olfactory neuroblastoma (ONB) is a rare neoplasm of the head and neck region that is included in the differential diagnosis of other sinonasal tract malignancies. We studied the usefulness of using p63 as an aid in the diagnosis of ONB and other tumors of the sinonasal region. The specimens were 14 ONBs; 4 nasopharyngeal carcinomas (NPCs), nonkeratinizing subtype; 2 NPCs, undifferentiated subtype; 10 sinonasal undifferentiated carcinomas (SNUCs); 7 malignant melanomas; and 2 extranodal natural killer (NK)/T-cell lymphomas. We observed p63 expression in 5 ONBs (36%), 4 nonkeratinizing NPCs (100%), 1 undifferentiated NPC (50%), 2 SNUCs (20%); 0 malignant melanomas (0%); and 1 extranodal NK/T-cell lymphoma (50%). While all cases of NPC with positive staining for p63 showed strong and diffuse immunoreactivity, the ONB, SNUC, and lymphoma cases with positive immunoreactivity showed only focal staining for p63. No p63 expression was observed in malignant melanoma. We think p63 is a useful marker to help distinguish nonkeratinizing or undifferentiated NPC subtypes from various sinonasal tract malignancies. In particular, p63 helps distinguish nonkeratinizing and undifferentiated NPC subtypes from SNUC.


Asunto(s)
Biomarcadores de Tumor/análisis , Estesioneuroblastoma Olfatorio/diagnóstico , Proteínas de la Membrana/análisis , Cavidad Nasal , Neoplasias Nasales/diagnóstico , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Inmunohistoquímica , Masculino , Persona de Mediana Edad , Neoplasias Nasofaríngeas/diagnóstico , Neoplasias de los Senos Paranasales/diagnóstico
6.
Arch Facial Plast Surg ; 9(6): 406-11, 2007.
Artículo en Inglés | MEDLINE | ID: mdl-18025351

RESUMEN

OBJECTIVE: To evaluate orbital and ophthalmologic function following standardized eye-sparing protocol for treating superior nasal vault malignant neoplasms. DESIGN: A retrospective review of patients with sinonasal malignant neoplasms who underwent preoperative radiation therapy with or without chemotherapy and craniofacial resection (CFR) with eye preservation. Pretreatment and posttreatment ophthalmologic evaluations were performed. RESULTS: A total of 59 patients underwent eye-sparing therapy between 1983 and 2005; 36 had invasion of the lamina with or without periorbital resection (61%). The most common abnormality was esthesioneuroblastoma (37 cases; 63%), most of which were Kadish stage C (n = 26). The most common preoperative ophthalmologic findings were motility disturbances (18 cases; 31%), afferent pupillary dysfunction and change in acuity (17 cases; 29%), and proptosis (17 cases; 29%). A total of 36 patients were available for long-term follow-up (mean follow-up, 61 months); 35 of these retained functional vision (97%); and 1 patient had a nonfunctional eye. CONCLUSIONS: Standardized treatment for superior nasal vault malignant neoplasms using an eye-sparing CFR remains a sound approach both oncologically and ophthalmologically. Most patients with advanced disease present with ophthalmologic findings, and most posttreatment eye findings are notable only on detailed examination and either resolve spontaneously in the acute-care setting or do not require surgical repair.


Asunto(s)
Fenómenos Fisiológicos Oculares , Neoplasias de los Senos Paranasales/cirugía , Procedimientos de Cirugía Plástica/métodos , Terapia Recuperativa/métodos , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Niño , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad
7.
JAMA Otolaryngol Head Neck Surg ; 143(7): 679-684, 2017 07 01.
Artículo en Inglés | MEDLINE | ID: mdl-28418509

RESUMEN

Importance: Hypocalcemia is the most common complication after total thyroidectomy and can result in prolonged hospital admissions and increased hospital charges. Objective: To determine the effectiveness of preoperative calcium and calcitriol supplementation in reducing hypocalcemia following total thyroidectomy. Design, Setting, and Participants: A retrospective cohort study was conducted at a tertiary care center in 65 patients undergoing total thyroidectomy by a single surgeon. Patients were divided into 2 groups: those receiving preoperative as well as postoperative supplementation with calcium carbonate, 1000 to 1500 mg, 3 times daily and calcitriol, 0.25 to 0.5 µg, twice daily, and those receiving only postoperative supplementation with those agents at the same dosages. Data on patients who underwent surgery between January 1, 2008, and December 31, 2011, were acquired, and data analyses were conducted from March through June 2012, and from October through December 2016. Interventions: Calcium and calcitriol therapy. Main Outcomes and Measures: Postoperative serum calcium levels and development of postoperative hypocalcemia. Results: Of the 65 patients who underwent total thyroidectomy 27 (42%) were men; mean (SD) age was 49.7 (16.7) years. Thirty-three patients received preoperative calcium and calcitriol supplementation, and 32 patients received only postoperative therapy. In the preoperative supplementation group, 15 of 33 (45%) patients underwent complete central compartment neck dissection and 11 of 33 (33%) had lateral neck dissection, compared with 16 of 32 (50%) and 12 of 32 (38%), respectively, patients without preoperative supplementation. The mean measured serum calcium level in those without preoperative supplementation vs those with supplementation are as follows: preoperative, 9.6 vs 9.4 mg/dL (absolute difference, 0.16; 95% CI, -0.12 to 0.49 mg/dL); 12 hours postoperative, 8.3 vs 8.6 mg/dL (absolute difference, -0.30; 95% CI, -0.63 to 0.02 mg/dL); and 24 hours postoperative, 8.4 vs 8.5 mg/dL (absolute difference, -0.13; 95% CI, -0.43 to 0.16 mg/dL). In patients not receiving preoperative supplementation, 5 of 32 (16%) individuals became symptomatically hypocalcemic vs 2 of 33 (6%) in the preoperative supplementation group; an absolute difference of 10% (95% CI, -6.6% to 26.3%). Compared with the group not receiving preoperative supplementation, the mean [SD] length of stay was significantly shorter in the preoperative supplementation group (3.8 [1.8] vs 2.9 [1.4] days; absolute difference, -0.9; 95% CI, -1.70 to -0.105 days). Preoperative supplementation resulted in an estimated $2819 savings in charges per patient undergoing total thyroidectomy. Conclusions and Relevance: Preoperative calcium and calcitriol supplementation, in addition to routine postoperative supplementation, was associated with a reduced incidence of symptomatic hypocalcemia, length of hospital stay, and overall charges following total thyroidectomy.


Asunto(s)
Calcitriol/uso terapéutico , Calcio/uso terapéutico , Hipocalcemia/prevención & control , Complicaciones Posoperatorias/prevención & control , Tiroidectomía , Calcitriol/sangre , Calcio/sangre , Femenino , Precios de Hospital , Humanos , Hipocalcemia/epidemiología , Incidencia , Tiempo de Internación/estadística & datos numéricos , Masculino , Persona de Mediana Edad , Disección del Cuello , Cuidados Posoperatorios , Complicaciones Posoperatorias/epidemiología , Cuidados Preoperatorios , Estudios Retrospectivos
8.
Arch Otolaryngol Head Neck Surg ; 132(2): 134-8, 2006 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-16490869

RESUMEN

OBJECTIVES: To analyze outcomes and to provide follow-up for our increasing patient cohort with esthesioneuroblastoma. DESIGN: Retrospective cohort analysis. SETTING: Patients were examined from September 1, 1976, to May 30, 2004, in a tertiary care academic hospital. PATIENTS: Fifty consecutive patients diagnosed as having esthesioneuroblastoma were treated with a standardized protocol during a 28-year period. Patients with tumors staged Kadish A or B received preoperative radiotherapy followed by craniofacial resection, while patients with Kadish stage C disease were treated with preoperative sequential chemotherapy and radiotherapy followed by a craniofacial resection. The mean follow-up is 93 months (range, 1-330 months). RESULTS: The disease-free survival was 86.5% and 82.6% at 5 and 15 years, respectively. There were 17 patients (34%) who developed recurrent disease, most of which was locoregional (12 patients [71%]). There was a long interval to relapse (mean, 6 years), with the longest time to regional recurrence being 10 years. Distant relapses occurred sooner, with poorer outcomes. Of these 17 patients, 7 (41%) underwent successful salvage surgery, while 3 remain alive with disease. CONCLUSIONS: Excellent outcomes for esthesioneuroblastoma are achievable. Long-term follow-up is necessary because of the extended interval for recurrent disease; unlike most sinonasal malignancies, surgical salvage is possible.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Estesioneuroblastoma Olfatorio , Cavidad Nasal , Procedimientos Neuroquirúrgicos/métodos , Neoplasias Nasales , Adolescente , Adulto , Anciano , Niño , Ciclofosfamida/administración & dosificación , Doxorrubicina/administración & dosificación , Estesioneuroblastoma Olfatorio/tratamiento farmacológico , Estesioneuroblastoma Olfatorio/radioterapia , Estesioneuroblastoma Olfatorio/cirugía , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Recurrencia Local de Neoplasia , Neoplasias Nasales/tratamiento farmacológico , Neoplasias Nasales/radioterapia , Neoplasias Nasales/cirugía , Radioterapia Adyuvante , Estudios Retrospectivos , Resultado del Tratamiento , Vincristina/administración & dosificación
9.
Arch Otolaryngol Head Neck Surg ; 132(1): 73-8, 2006 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-16415433

RESUMEN

OBJECTIVE: To report postoperative mortality, complications, and outcomes in a subset of patients with the histologic diagnosis of malignant melanoma extracted from an existing database of a large cohort of patients accumulated from multiple institutions. DESIGN: Retrospective outcome analysis. SETTING: Seventeen international tertiary referral centers performing craniofacial surgery for malignant skull base tumors. PATIENTS: A total of 53 patients were identified from a database of 1307 patients who had craniofacial resection for malignant tumors at 17 institutions. The median age was 63 years. Of the 53 patients, 25 (47%) had had prior single modality or combined treatment, which included surgery in 22 (42%), radiation in 11 (21%), and chemotherapy in 2 (4%). The margins of resection were close or microscopically positive in 7 (13%). Adjuvant radiotherapy was given in 22 (42%), chemotherapy in 3 (6%), and vaccine or interferon therapy in 2 (4%). Complications were classified into overall, local, central nervous system, systemic, and orbital. Overall survival (OS), disease-specific survival (DSS), and recurrence-free survival (RFS) were determined using the Kaplan-Meier method. Predictors of outcome were identified by multivariate analysis. RESULTS: Postoperative mortality occurred in 3 patients (6%) and postoperative complications were reported in 14 patients (26%). Local wound complications occurred in 6 patients (11%), central nervous system in 7 (13%), systemic in 3 (6%), and orbital in 1 (2%). With a median follow-up of 10 months (range, 1-159 months), the 3-year OS, DSS, and RFS rates were 28.2%, 29.7%, and 25.5%, respectively. The extent of orbital involvement and adjuvant postoperative radiation therapy (PORT) were independent predictors of DSS and OS on multivariate analysis, whereas only PORT was an independent predictor of RFS. Patients treated with PORT had significantly better 3-year OS (39% vs 18%; relative risk, 2.9; P = .007), DSS (41% vs 19%; relative risk, 3.0; P = .007), and RFS (39% vs 15%; relative risk, 4.2; P = .001). CONCLUSIONS: Craniofacial resection in patients with malignant melanoma of the skull base has mortality (6%) and complication rates (26%) comparable to other malignant tumors of the skull base. However, malignant melanoma is associated with a much poorer OS, DSS, and RFS. Adjuvant PORT correlated with improved 3-year OS, DSS, and RFS on multivariate analysis. These factors must be taken into account when considering craniofacial resection in a patient with malignant melanoma invading the skull base.


Asunto(s)
Fosa Craneal Anterior/cirugía , Huesos Faciales/cirugía , Melanoma/cirugía , Neoplasias de la Base del Cráneo/cirugía , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Niño , Preescolar , Supervivencia sin Enfermedad , Femenino , Estudios de Seguimiento , Humanos , Cooperación Internacional , Masculino , Melanoma/epidemiología , Melanoma/patología , Persona de Mediana Edad , Invasividad Neoplásica , Recurrencia Local de Neoplasia , Estudios Retrospectivos , Neoplasias de la Base del Cráneo/epidemiología , Neoplasias de la Base del Cráneo/patología , Tasa de Supervivencia
10.
JAMA Otolaryngol Head Neck Surg ; 142(1): 40-5, 2016 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-26633039

RESUMEN

IMPORTANCE: Rigid esophagoscopy (RE) was once an essential part of the evaluation of patients with head and neck squamous cell carcinoma (HNSCC) due to the high likelihood of identifying a synchronous malignant neoplasm in the esophagus. Given recent advances in imaging and endoscopic techniques and changes in the incidence of esophageal cancer, the current role for RE in HNSCC staging is unclear. OBJECTIVE: To analyze the current role of RE in evaluating patients with HNSCC, and to determine the incidence of synchronous esophageal malignant neoplasms in patients with HNSCC. DESIGN, SETTING, AND PARTICIPANTS: In this retrospective study performed at an academic tertiary care center, 582 patients were studied who had undergone RE for HNSCC staging from July 1, 2004, through October 31, 2012. To assess the incidence of synchronous esophageal malignant neoplasms, a literature review was performed, and the National Cancer Institute's Surveillance, Epidemiology, and End Results (SEER) data set was queried. MAIN OUTCOMES AND MEASURES: The primary outcome measure was the incidence of synchronous esophageal malignant neoplasms, as measured by retrospective review at our institution, SEER data set analysis, and literature review. Secondary outcome measures were RE complications and nonmalignant findings during RE. RESULTS: A total of 601 staging REs were performed in 582 patients. The mean age was 60.2 years and 454 (78.0%) were men. There were 9 complications (1.5%), including 1 esophageal perforation (0.2%). Rigid esophagoscopy was aborted in 50 cases. Of the 551 completed REs, no abnormal findings were noted in 523 patients (94.9%), and nonmalignant pathologic findings were identified in 28 patients (5.1%). No synchronous primary esophageal carcinomas were detected. The incidence of synchronous esophageal malignant neoplasms found on screening endoscopy based on literature review and on SEER data set analysis was very low and has decreased from 1980 to 2010 in North America. The incidence reported in South America and Asia was relatively high. CONCLUSIONS AND RELEVANCE: Rigid esophagoscopy is safe, but the utility is low for cancer staging and for detection of nonmalignant esophageal disease. Review of the literature and analysis of a large national cancer data set indicate that the incidence of synchronous esophageal malignant neoplasms in patients with HNSCC is low and has been decreasing during the past 3 decades. Thus, screening esophagoscopy should be limited to patients with HNSCC who are at high risk for synchronous esophageal malignant neoplasms.


Asunto(s)
Carcinoma de Células Escamosas/epidemiología , Carcinoma de Células Escamosas/patología , Neoplasias Esofágicas/epidemiología , Neoplasias Esofágicas/patología , Esofagoscopía , Neoplasias de Cabeza y Cuello/epidemiología , Neoplasias de Cabeza y Cuello/patología , Neoplasias Primarias Múltiples/epidemiología , Neoplasias Primarias Múltiples/patología , Femenino , Humanos , Incidencia , Masculino , Persona de Mediana Edad , Estadificación de Neoplasias , Evaluación de Resultado en la Atención de Salud , Estudios Retrospectivos , Programa de VERF , Carcinoma de Células Escamosas de Cabeza y Cuello , Estados Unidos/epidemiología
12.
Laryngoscope ; 125(8): 1856-60, 2015 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-25891166

RESUMEN

OBJECTIVES/HYPOTHESIS: Treatment of cutaneous melanoma involves surgical excision with wide clinical margins. No guidelines regarding safe histopathologic margin distance exist. This study examines the impact of histopathologic margin, measured from closest cut edge of the specimen, on overall survival in resection of cutaneous melanoma of the head and neck. We hypothesize that close histopathologic margins (<2 mm) are associated with decreased survival. STUDY DESIGN: Retrospective chart review. METHODS: A total of 637 patients were treated for cutaneous melanoma of the head and neck between 2001 and 2011. Demographics, tumor characteristics, histopathologic margin distance (from a pathology database), and survival data from state health registries and health system clinical data repositories were used to create a dataset. Cox regression models and Kaplan-Meier curves were used to analyze data, adjusting for age, tumor location, ulceration, and depth of invasion (DOI). RESULTS: When analyzing for overall survival, Cox multivariate regression analysis showed age (hazard ratio [HR] = 1.0-1.1), DOI (HR = 1.2-1.5), ulceration (HR = 1.3-3.8), and subsite (ear, HR = 1.0-3.9) were significant predictors of survival. Histopathologic margin distance was not significant for predicting survival. Three percent of histopathologic margins were <1 mm. CONCLUSIONS: In a large dataset of head and neck cutaneous melanoma, known factors associated with overall survival (age, DOI, ulceration, subsite) proved significant, validating the dataset. Examining the effect of histopathologic margin distance on survival, while controlling for these factors, we failed to reject the null hypothesis. Margin distance as measured by histopathology does not affect survival. LEVEL OF EVIDENCE: 4.


Asunto(s)
Neoplasias de Cabeza y Cuello/patología , Neoplasias de Cabeza y Cuello/cirugía , Melanoma/patología , Melanoma/cirugía , Estadificación de Neoplasias , Adolescente , Adulto , Anciano , Niño , Preescolar , Supervivencia sin Enfermedad , Femenino , Estudios de Seguimiento , Neoplasias de Cabeza y Cuello/epidemiología , Humanos , Incidencia , Lactante , Recién Nacido , Masculino , Melanoma/epidemiología , Persona de Mediana Edad , Modelos de Riesgos Proporcionales , Estudios Retrospectivos , Neoplasias Cutáneas , Tasa de Supervivencia/tendencias , Virginia/epidemiología , Adulto Joven , Melanoma Cutáneo Maligno
13.
Am Heart J ; 147(1): 127-31, 2004 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-14691430

RESUMEN

BACKGROUND: AutoCapture (AC) is a programmable feature that enables the pacemaker to both track the capture threshold and automatically adjust the output on a beat-by-beat basis. Although AC safely and significantly reduces the current drainage, some authors have argued that the longevity benefit of such a system is overstated. This study aims to estimate the longevity extension that can be obtained, in the clinical routine, by turning the AC on in comparison to pacemakers programmed to operate at the shipped and manually optimized output. METHODS: We selected 83 consecutive patients who received implanted St Jude's Affinity pacemakers >6 months earlier. Eight patients died or were lost to follow-up and in 9 subjects the AC could not be turned on. In the remaining 66 patients, current drain and estimated longevity were compared in 3 situations: (1) AC on; (2) AC off, optimized programming (100%-150% voltage threshold); (3) AC off, shipped output (3.5 V). RESULTS: Five patients had large variations (>1 V) of the AC threshold. Current drainage was 8.0 +/- 0.9 mA in the AC group, 8.7 +/- 1.8 mA with AC off and optimized programming, and 11.3 +/- 2.3 mA at shipped output (P <.01). Estimated longevity was significantly extended (P <.01) by AC (12.1 +/- 1.0 years) when compared to shipped (8.9 +/- 1.7 years) and optimized programming (11.3 +/- 1.4 years). CONCLUSION: Reprogramming the pacemaker output significantly enhanced its estimated longevity; AC added a moderate but significant extension over manual reprogramming and was associated with increased safety in patients with large ventricular threshold variations.


Asunto(s)
Suministros de Energía Eléctrica , Bloqueo Cardíaco/terapia , Marcapaso Artificial , Síndrome del Seno Enfermo/terapia , Algoritmos , Calibración , Estimulación Cardíaca Artificial , Falla de Equipo , Femenino , Bloqueo Cardíaco/fisiopatología , Humanos , Masculino , Persona de Mediana Edad , Factores de Tiempo
14.
Laryngoscope ; 112(8 Pt 1): 1450-5, 2002 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-12172261

RESUMEN

OBJECTIVE: To evaluate the clinical outcomes of a standardized treatment approach for sinonasal undifferentiated carcinoma (SNUC). STUDY DESIGN: Single-center, retrospective case series. METHODS: Fifteen patients with newly diagnosed SNUC were seen in the Department of Otolaryngology-Head and Neck Surgery at the University of Virginia from 1991 to 2000. Long-term follow-up on five additional patients diagnosed between 1986 and 1991 was also analyzed. RESULTS: Overall, 10 patients were treated with curative intent with neoadjuvant chemoradiotherapy followed by craniofacial resection (CFR). The majority of the remainder was treated with palliative radiotherapy or chemoradiotherapy alone. Four patients who underwent CFR are currently free of disease at 4, 36, 49, and 164 months postoperatively. The 2-year survival of all evaluable patients, regardless of treatment, was 47%. Two-year survival was 64% in the group treated by CFR and 25% in the group treated with chemo- and/or radiotherapy (P =.076). CONCLUSION: For patients with good performance status and limited intracranial or intraorbital disease, we continue to advocate initial chemoradiotherapy followed by craniofacial resection. Patients who are deemed inoperable as a result of advanced disease may nevertheless experience significant palliation with chemoradiotherapy only.


Asunto(s)
Carcinoma/terapia , Neoplasias de los Senos Paranasales/terapia , Adulto , Anciano , Anciano de 80 o más Años , Terapia Combinada , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Resultado del Tratamiento
15.
Laryngoscope ; 112(12): 2192-5, 2002 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-12461340

RESUMEN

OBJECTIVES/HYPOTHESIS: Laryngitis secondary to gastric acid reflux is a prevalent, yet incompletely understood, otolaryngological disorder. Further characterization of the relationship between symptoms and signs and reflux severity is needed. STUDY DESIGN: Prospective clinical trial. METHODS: Forty-two consecutive, nonsmoking patients with one or more reflux laryngitis symptoms were recruited to complete a symptom questionnaire, videostrobolaryngoscopy, and 24-hour, dual-sensor pH probe testing. Twenty-nine patients had more than four episodes of laryngopharyngeal reflux, and the remaining 13 served as control subjects. Symptom scores were produced by multiplying the severity by the frequency for the following: hoarseness, throat pain, "lump-in-throat" sensation, throat clearing, cough, excessive phlegm, dysphagia, odynophagia, and heartburn. Endoscopic laryngeal signs included erythema and edema of the vocal folds and arytenoids, and interarytenoid irregularity. RESULTS: Symptom scores varied significantly, with throat clearing being greater than the rest. None of the symptoms, except heartburn, correlated with reflux (laryngopharyngeal and esophageal) severity. Patients with worse laryngopharyngeal reflux were found to have worse esophageal reflux. Endoscopic laryngeal signs were rated as mild, on average, and did not correlate with laryngopharyngeal reflux severity. The number of laryngopharyngeal reflux episodes (per 24 h) ranged from 0 to 40 (mean number, 10.6 episodes). CONCLUSIONS: Throat clearing was the most intense symptom in the present group of patients with proven reflux laryngitis. Dual-sensor pH probe testing could not predict the severity of patient's reflux laryngitis symptoms or signs. Only the heartburn symptom correlated with laryngopharyngeal and esophageal reflux.


Asunto(s)
Reflujo Gastroesofágico/diagnóstico , Laringitis/diagnóstico , Adulto , Femenino , Reflujo Gastroesofágico/complicaciones , Pirosis/etiología , Humanos , Concentración de Iones de Hidrógeno , Electrodos de Iones Selectos , Laringitis/etiología , Masculino , Persona de Mediana Edad , Estudios Prospectivos
16.
Neurosurg Focus ; 12(5): e4, 2002 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-16119902

RESUMEN

Esthesioneuroblastoma is a rare and malignant upper nasal cavity neoplasm involving the anterior skull base. Treatment includes surgery, radiotherapy, chemotherapy, or a combination. The ideal treatment modality has yet to be determined. Esthesioneuroblastoma often lies in proximity to the optic nerves, optic chiasm, and the orbit. Resection risks damaging these critical structures, and radiotherapeutic techniques, similar to those applied for paranasal sinus tumors, may damage these vital structures and result in late sequelae such as blindness and cortical necrosis. Management strategies for this neoplasm lack uniformity, and there is no universally accepted staging system. In this paper the authors discuss the clinical presentation, radiological and pathological features, and treatment of this rare, malignant skull base neoplasm, as well as review the literature. They also present their results and treatment regimen, which includes preoperative radio- and chemotherapy or 1) craniofacial resection if the lesion has a significant intracerebral component, or 2) frontal sinus resection if little intracranial extension exists.


Asunto(s)
Estesioneuroblastoma Olfatorio , Cavidad Nasal , Neoplasias Nasales , Adolescente , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Quimioterapia Adyuvante , Niño , Estudios de Cohortes , Terapia Combinada , Estesioneuroblastoma Olfatorio/diagnóstico , Estesioneuroblastoma Olfatorio/diagnóstico por imagen , Estesioneuroblastoma Olfatorio/genética , Estesioneuroblastoma Olfatorio/patología , Estesioneuroblastoma Olfatorio/cirugía , Estesioneuroblastoma Olfatorio/terapia , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Recurrencia Local de Neoplasia/epidemiología , Estadificación de Neoplasias , Neoplasias Nasales/diagnóstico , Neoplasias Nasales/diagnóstico por imagen , Neoplasias Nasales/genética , Neoplasias Nasales/patología , Neoplasias Nasales/cirugía , Neoplasias Nasales/terapia , Complicaciones Posoperatorias , Radiografía , Radioterapia Adyuvante , Estudios Retrospectivos , Resultado del Tratamiento
17.
Indian Pacing Electrophysiol J ; 3(2): 88-90, 2003 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-16943962

RESUMEN

BACKGROUND: Sinus node dysfunction, atrioventricular (AV) block and atrial fibrillation (AF) are associated with advanced age. Required therapy commonly includes pacemaker implantation. METHODS: We report the course of therapy for an 87-year-old with symptomatic sinus node dysfunction and paroxysmal atrial fibrillation who was intolerant of drug therapy. RESULTS: The patient received a pacemaker for treatment of sick sinus syndrome. She continued to have symptomatic episodes of AF and was intolerant of pharmacologic therapy despite adequate rate support provided by the pacemaker. The AF suppression algorithm in the pacemaker was enabled, resulting in the elimination all AF episodes effectively eliminating the need for antiarrhythmic medication. If this continues to stabilize her atrium, withdrawal of anticoagulation therapy is anticipated. CONCLUSIONS: The clinical presentation of sinus node dysfunction and related conduction abnormalities is common in the elderly. Pharmacologic management is often a challenge in the presence of the advanced age and concomitant disease processes. In individuals who have paroxysmal atrial fibrillation or are likely to develop this and who need a pacemaker for standard indications, the availability of an AF Suppression algorithm may facilitate their management without needed to use medications or being able to utilize lower doses of those medications.

18.
JAMA Otolaryngol Head Neck Surg ; 140(7): 647-53, 2014 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-24876098

RESUMEN

IMPORTANCE: The prognostic significance of p16 in squamous cell carcinoma (SCC) of the hypopharynx (HP) and nasopharynx (NP) and relationship between human papillomavirus (HPV) and p16 is unclear. OBJECTIVES: To evaluate the prognostic significance of p16 in pharyngeal subsites (oropharynx [OP], HP, and NP) and assess the relationship between HPV and p16 in the HP and NP. DESIGN, SETTING, AND PARTICIPANTS: Retrospective medical record review of 172 patients with SCC of the pharynx treated with definitive radiation therapy from 2002 to 2013 at a university tertiary referral center, with tissue available for immunohistochemical analysis. The median follow-up was 30.1 months. INTERVENTIONS: A total of 118 patients were treated with chemoradiation, and 54 patients were treated with radiation alone. Immunohistochemical analysis for p16 was performed for all tumors. Hypopharynx and NP tumors were tested for HPV using in situ hybridization, and NP tumors were tested for Epstein-Barr virus. MAIN OUTCOMES AND MEASURES: Overall survival, locoregional control, and disease-free survival were analyzed according to p16, HPV, and Epstein-Barr virus status. RESULTS: Thirty-two patients had HP SCC, 127 had OP SCC, and 13 had NP SCC. p16 Was positive in the HP (34%), OP (66%), and NP (46%). Prevalence of HPV was 14% in the HP and 50% in the NP. As a test for HPV, p16 had a positive predictive value of 38% (HP) and 67% (NP) and a negative predictive value of 100% in HP and NP tumors. p16 Status was a significant predictor of all clinical outcomes for patients with OP SCC (P<.001), but not for patients with HP or NP SCC. Patients with Epstein-Barr virus- or HPV-associated NP SCC had improved clinical outcomes. CONCLUSIONS AND RELEVANCE: p16 Was not associated with improved outcomes in patients with HP or NP SCC. The positive predictive value of p16 as a test for HPV is too low for p16 testing alone in the HP and NP. However, p16 negativity is sufficient to rule out HPV. As a research approach, we recommend p16 immunohistochemistry as a screening test for HPV in NP SCC and HP SCC followed by confirmatory HPV in situ hybridization when p16 positive.


Asunto(s)
Carcinoma de Células Escamosas/mortalidad , Genes p16/fisiología , Neoplasias Faríngeas/mortalidad , Faringe/química , Biomarcadores/análisis , Carcinoma de Células Escamosas/terapia , Supervivencia sin Enfermedad , Femenino , Humanos , Inmunohistoquímica , Hibridación in Situ , Masculino , Persona de Mediana Edad , Nasofaringe/química , Orofaringe/química , Virus de la Parainfluenza 1 Humana/aislamiento & purificación , Neoplasias Faríngeas/terapia , Pronóstico , Planificación de la Radioterapia Asistida por Computador , Análisis de Regresión
19.
Laryngoscope ; 123(3): 683-8, 2013 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-23404736

RESUMEN

OBJECTIVES/HYPOTHESIS: Head and neck melanoma surgeons must achieve negative margins before performing margin compromising reconstructions such as a local flap closure. This often necessitates staged operations, including further margin resection. Peripheral sampling is often used before definitive resection to help guide the extent of the resection. If melanoma margin status could be predicted based on lesion characteristics, the surgeon could be more confident in performing definitive closure immediately after resection of some lesions or confident in the need to take larger margins in predictably extensive lesions. STUDY DESIGN: Retrospective review and logistic regression analysis. METHODS: Institutional review board approval was obtained. Out of 637 patients treated for head and neck melanoma by the Department of Otolaryngology-Head and Neck Surgery in the last 10 years, 409 patients had primary resection with available histopathologic margin status used as the outcome variable. Predictor variables of demographics, lesion size, pathologic subtype, location on face, and depth of invasion were collected. RESULTS: Histopathologic margin status could be predicted by age but not by the other predictor variables. CONCLUSIONS: In this large series of head and neck melanomas excised using National Comprehensive Cancer Network-recommended margins, histopathologic margin status could be predicted based on age but not on lesion characteristics. This finding is surprising given the published data showing that melanoma in situ has a higher rate of positive margin compared to subtypes of invasive melanoma. It reinforces the need for delaying reconstruction until margins are clear or performing reconstruction at a time of resection that does not compromise the ability to resect margins further (e.g., skin graft).


Asunto(s)
Neoplasias de Cabeza y Cuello/patología , Melanoma/patología , Melanoma/cirugía , Neoplasias Cutáneas/patología , Neoplasias Cutáneas/cirugía , Adulto , Anciano , Neoplasias Faciales/patología , Humanos , Modelos Logísticos , Persona de Mediana Edad , Estadificación de Neoplasias , Curva ROC , Procedimientos de Cirugía Plástica , Estudios Retrospectivos
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