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1.
Sci Rep ; 8(1): 9550, 2018 06 22.
Artigo em Inglês | MEDLINE | ID: mdl-29934522

RESUMO

Given the increasing demand for wheat which is forecast, cropping of wheat in short rotations will likely remain a common practice. However, in temperate wheat growing regions the soil-borne fungal pathogen Gaeumannomyces tritici becomes a major constraint on productivity. In cultivar rotation field experiments on the Rothamsted Farm (Hertfordshire, UK) we demonstrated a substantial reduction in take-all disease and grain yield increases of up to 2.4 tonnes/ha when a low take-all inoculum building wheat cultivar was grown in the first year of wheat cropping. Phenotyping of 71 modern elite wheat cultivars for the take-all inoculum build-up trait across six diverse trial sites identified a few cultivars which exhibited a consistent lowering of take-all inoculum build-up. However, there was also evidence of a significant interaction effect between trial site and cultivar when a pooled Residual Maximum Likelihood (REML) procedure was conducted. There was no evidence of an unusual rooting phenotype associated with take-all inoculum build-up in two independent field experiments and a sand column experiment. Together our results highlight the complex interactions between wheat genotype, environmental conditions and take-all inoculum build-up. Further work is required to determine the underlying genetic and mechanistic basis of this important phenomenon.


Assuntos
Agricultura/métodos , Ascomicetos/fisiologia , Microbiologia do Solo , Triticum/crescimento & desenvolvimento , Triticum/microbiologia , Ambiente Controlado , Fenótipo , Doenças das Plantas/microbiologia , Raízes de Plantas/crescimento & desenvolvimento
2.
J Clin Oncol ; 21(24): 4553-9, 2003 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-14597743

RESUMO

PURPOSE: For the first time, a lung Patterns of Care Study was conducted to determine the national patterns of radiation (RT) practice in patients treated for nonmetastatic lung cancer in 1998 to 1999. MATERIALS AND METHODS: A national survey of randomly selected RT institutions in the United States was conducted using two-stage cluster sampling, stratified by practice type. Patients with nonmetastatic lung cancer (Karnofsky performance score [KPS] > or = 60), who received RT as definitive or adjuvant therapy, were randomly selected. To determine national estimates, sample size was weighted by the relative number of institutions per strata and the number of patient records reviewed per the number of patients eligible. Accordingly, 42,335 patient records from 58 institutions were reviewed by trained research associates. The unweighted sample size (or number of patients) was 541. RESULTS: The histologies were small-cell lung cancer (SCLC) in 14.5% of patients versus non-small-cell lung cancer (NSCLC) in 85.5% of patients. The median age was 67 years (range, 29 to 92 years); 61% of patients were male, and 38% were current smokers. Bone scans and brain imaging were not obtained in 34% and 52% of clinical stage (CS) III NSCLC patients, respectively. Regarding treatment strategies, for SCLC and CS III NSCLC, chemotherapy plus RT was used significantly more than RT alone (P <.05); in CS I NSCLC, RT alone was the primary treatment (P <.05). Overall, 58% of patients received systemic therapy. On multivariate analysis, factors correlating with increased use of chemotherapy included younger age, histology (SCLC > NSCLC), increasing CS, increasing KPS, and lack of comorbidities. Only 3% of all patients were treated on prospective clinical trials. CONCLUSION: This study establishes the general patterns of care for lung carcinoma in RT facilities within the United States. As supported by clinical trials, patients with limited-stage SCLC and CS III NSCLC received chemotherapy plus RT more than they received RT alone. Further improvements in staging, smoking cessation, and increased accrual to clinical trials must be encouraged.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/radioterapia , Carcinoma de Células Pequenas/radioterapia , Neoplasias Pulmonares/radioterapia , Padrões de Prática Médica , Adulto , Idoso , Idoso de 80 Anos ou mais , Distribuição de Qui-Quadrado , Feminino , Fidelidade a Diretrizes , Humanos , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Seleção de Pacientes , Qualidade da Assistência à Saúde , Estudos de Amostragem , Estados Unidos
3.
Int J Radiat Oncol Biol Phys ; 50(2): 325-34, 2001 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-11380218

RESUMO

PURPOSE: Five-year results from the 1989 patterns of care study (PCS) for prostate cancer are now ready for analysis. The PCS was initiated to determine national averages for treatments and examine outcomes prospectively; the 1989 prostate study is the first to have collected pre- and post-treatment serum PSA data. METHODS AND MATERIALS: Six hundred patients treated with radiotherapy with curative intent for prostate cancer at 71 separate institutions in the year 1989 made up the study population. Three hundred ninety-one cases were fully analyzable. Pretreatment patient and tumor characteristics were as follows: of the 391 analyzable, 255 had pretreatment PSA values obtained, and 245 had a Gleason's sum (GS) reported. Three hundred fifty-eight were Caucasian, 24 African-American, and 3 Hispanic (also 6 unknown). One hundred three patients had PSA < 10, 60 had PSA 10-19, and 92 presented with PSA >20. Ninety-seven patients were from Radiation Therapy Oncology Group (RTOG), Community Cancer Centers (CCC), or teaching institutions; 141 patients were from other hospital-based, nonteaching institutions; and 153 were from freestanding radiation oncology facilities. Seventy-one patients were T1, 203 T2, and 100 T3/4. Twenty-four out of 391 patients also received neoadjuvant hormone therapy. Survival curves were constructed using Kaplan-Meier methods, and differences between groups were tested for significance using the log-rank test. For cumulative incidence curves, Gray's test was used to investigate failure distributions between groups. The variables entering Cox model for multivariate analysis included age, race, T stage, pretreatment PSA, and GS. A patient was considered a PSA failure if the treating radiation oncologist reported it as such. RESULTS: With a median follow-up of 5.7 years, the 5-year biochemical no evidence of disease (bNED) and overall survival were 56% and 79% respectively for Stage T1, 52% and 81% for T2, and 36% and 63% for Stages T3 and T4 combined. As expected, higher pretreatment PSA, GS, and T stage were all prognostic of poorer outcome. On univariate analysis, bNED survival was adversely impacted by T stage (p = 0.009), pretreatment PSA (p = 0.0035), and by the GS (p = 0.0038). Cause-specific failure was significantly lower for higher T stage (p = 0.014), GS (p = 0.001), and also pretreatment PSA (p = 0.0004). Overall survival was significantly lower in patients with higher T stage (p = 0.047) or GS (p = 0.0191), but not pretreatment PSA (p = 0.284). On multivariate analysis, pretreatment PSA was found to be statistically significant in association with bNED survival, and GS was associated with overall survival, cause-specific survival, and distant metastasis. Few late complications were reported: 13/391 and 13/391 Grade 2-3 gastrointestinal (GI) and genitourinary (GU) complications respectively, with two patients having required surgery with or without a permanent colostomy. CONCLUSION: For a representative cross-section of institutions in the United States, radiotherapy achieved high rates of bNED and CSS in selected groups of prostate cancer patients. When studied retrospectively, increased pretreatment PSA was a strong predictor of both biochemical failure and death due to prostate cancer. New strategies for patients with high-stage, high-grade tumors and/or pretreatment PSA >20 deserve testing.


Assuntos
Neoplasias da Próstata/radioterapia , Idoso , Idoso de 80 Anos ou mais , Intervalo Livre de Doença , Humanos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Estadiamento de Neoplasias , Padrões de Prática Médica , Prognóstico , Estudos Prospectivos , Antígeno Prostático Específico/sangue , Neoplasias da Próstata/imunologia , Neoplasias da Próstata/patologia , Radioterapia Conformacional/normas , Taxa de Sobrevida , Resultado do Tratamento
4.
Int J Radiat Oncol Biol Phys ; 50(1): 75-80, 2001 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-11316549

RESUMO

PURPOSE: Over the last two decades, the chance for the cure of localized prostate cancer by radiation has been improved by the widespread use of PSA for early detection and by a number of technical advances in treatment delivery. This study was designed to determine whether the stage of presentation and the quality of radiation treatment delivered are comparable between Caucasian and minority patients nationally and within minority-rich areas. METHODS AND MATERIALS: A random survey conducted for the Patterns of Care Study in Radiation Oncology of 80 facilities treating patients with radiation in the USA. Of these, 67 comprise the "National Survey" and 13 a "Minority-Rich" survey (>40% of treated patients are minorities). Nine hundred twenty-six men with localized prostate cancer were treated in 1994. Five hundred ninety-five were in the national and 331 in the minority-rich survey. The main outcome measures were the clinical features of Caucasian and minority men at presentation and technical characteristics of the treatment delivered to them. RESULTS: African-American men presented with more advanced disease (higher-presenting PSA and T-stage) than Caucasians in both the national and the minority-rich surveys. Hispanics also presented with later disease and could be grouped with African-American men rather than Caucasians. Overall the stage and PSA at presentation was earlier than seen in the previous Patterns of Care Study survey of 1989. The quality of treatment delivered has improved since 1989, with no distinction seen between those facilities sampled nationally and those within minority-rich areas. CONCLUSION: African-American and Hispanic men with prostate cancer present for therapy at a later stage than Caucasian men, but when they do, the treatment received is of comparable quality.


Assuntos
Etnicidade/estatística & dados numéricos , Padrões de Prática Médica , Neoplasias da Próstata/radioterapia , Negro ou Afro-Americano/estatística & dados numéricos , Pesquisas sobre Atenção à Saúde , Hispânico ou Latino/estatística & dados numéricos , Humanos , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Padrões de Prática Médica/normas , Neoplasias da Próstata/patologia , Qualidade da Assistência à Saúde , População Branca/estatística & dados numéricos
5.
J Clin Oncol ; 19(8): 2254-62, 2001 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-11304779

RESUMO

PURPOSE: To define patterns of care for the local therapy of stage I and II breast cancer and to identify factors used to select patients for breast-conserving therapy (BCT). PATIENTS AND METHODS: A convenience sample of 16,643 patients with stage I and II breast cancer treated in 1994 was obtained from hospital-based tumor registries. Histologic variables were determined from original pathology reports. RESULTS: BCT was performed in 42.6% of patients. Multivariate analysis demonstrated that living in the Northeast United States (odds ratio [OR], 2.48; 95% confidence interval [CI], 2.16 to 2.84), having a clinical T1 tumor (OR, 2.51; 95% CI, 2.27 to 2.78), and having a tumor without an extensive intraductal component (OR, 2.07; 95% CI, 1.81 to 2.37) were the strongest predictors of breast-conserving surgery. Radiation therapy was given to 86% of patients who had breast-conserving surgery. Age less than 70 years was the most significant predictor of receiving radiation (OR, 2.11; 95% CI, 1.77 to 2.25). Tumor variables did not correlate with the use of radiation, but favorable tumor characteristics were associated with the use of breast-conserving surgery. CONCLUSION: Despite strong evidence supporting the use of BCT, the majority of women continue to be treated with mastectomy. Predictors of the use of BCT do not correspond to those suggested in guidelines.


Assuntos
Neoplasias da Mama/cirurgia , Mastectomia Segmentar/estatística & dados numéricos , Mastectomia/estatística & dados numéricos , Padrões de Prática Médica , Adulto , Fatores Etários , Idoso , Neoplasias da Mama/patologia , Feminino , Humanos , Pessoa de Meia-Idade , Invasividade Neoplásica , Estadiamento de Neoplasias , Razão de Chances , Radioterapia Adjuvante , Estudos Retrospectivos
6.
Int J Radiat Oncol Biol Phys ; 48(5): 1291-9, 2000 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-11121625

RESUMO

PURPOSE: To determine the patterns of evaluation and treatment in the U.S. of women with early breast cancer treated with breast-conserving surgery and irradiation in 1993-94, and to compare these with a similar survey in 1983 and with the 1992 Standard for Breast Conservation Treatment. METHODS AND MATERIALS: In 1995-96, 727 randomly selected records of eligible patients treated from 1993-94 at 62 facilities representative of 3 practice types were reviewed. RESULTS: Compared with the Process Survey (PS) in 1983, patients in the 1993-94 study had an older age distribution. In the current study, 70% of patients were > or = 50 years of age, and 69% were post-menopausal, compared with 59% > or = 50 years of age and 49% post-menopausal in 1983 (p = 0.0087 and < 0.001, respectively). Work-up and evaluation in the 1993-94 PS were closely aligned with the standard and were considerably improved compared with 1983. In the 1983 study, 77% of patients underwent mammography, as compared to 97% in the 1993-94 study. In 1983, pathological size documentation was performed in 83% of patients; in 1993-94, this was performed in 95% of patients. An estrogen receptor evaluation was performed in 36% of patients in 1983; in 1993-94, that increased to 76%. In 1983, 28% of patients underwent progesterone receptor evaluation; in 1993-94, this increased to 72%. Only 3% of patients in 1993-94 were enrolled in a clinical trial. Radiation treatment parameters closely adhered to standard recommendations, improving substantially from 1983. In 1983, wedge or compensator use was recommended for 64% of patients; in 1993-94, for 95% of patients. In 1983, 4-8 MV photons were recommended for breast treatment in 67% of patients; in 1993-94, 90%. In 1983, bolus was avoided in 75% of patients; in 1993-94, in 94%. In 1983, the recommended breast dose for 89% of patients was 45-50 Gy (44-51 Gy in PS); in 1993-94 this had increased to 99% of patients. In 1983, electrons were recommended for primary site boost in 70% of patients; in 1993-94, for 94% of patients. CONCLUSION: There was an extensive shift to adherence to the 1992 standard in 1993-94, compared with the 1983 PS, although there is room for improvement in some areas.


Assuntos
Neoplasias da Mama/radioterapia , Neoplasias da Mama/cirurgia , Padrões de Prática Médica/normas , Adulto , Distribuição por Idade , Idoso , Idoso de 80 Anos ou mais , Antineoplásicos/uso terapêutico , Axila , Feminino , Pesquisas sobre Atenção à Saúde , Humanos , Irradiação Linfática , Mamografia/estatística & dados numéricos , Mastectomia Segmentar , Pessoa de Meia-Idade , Proteínas de Neoplasias/análise , Estadiamento de Neoplasias , Neoplasia Residual , Guias de Prática Clínica como Assunto/normas , Dosagem Radioterapêutica , Receptores de Estrogênio/análise , Receptores de Progesterona/análise , Reoperação/estatística & dados numéricos , Estudos Retrospectivos
7.
Int J Radiat Oncol Biol Phys ; 47(2): 443-50, 2000 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-10802372

RESUMO

PURPOSE: To describe the relationship between socioeconomic variables and the treatment of patients with radiotherapy for cervix cancer.40% minority patients. METHODS AND MATERIALS: Sixty-two institutions werw r andomly selected from a list of all radiotherapy facilities in the Unite d States. From these we randomly selected and reviewed 471 cases of squ amous cell carcinoma treated during 1992 to 1994. To create an addition al minority-rich sample, we randomly selected 215 additional cases from 17 randomly selected institutions that admitted >40% minority patients. The median household income of each patient's neighborhood was determined by matching her zip code to data from the 1990 United States Census. RESULTS: Pati ents who lived in low-income neighborhoods, who had only Medicaid covera ge, or who were treated at large academic or minority-rich institutions tended to have a poorer initial performance status, higher-stage or bulk y central disease, and a lower pretreatment hemoglobin level. Ability t o complete treatment did not correlate with ethnicity or income. Howeve r, noncompliant patients tended to be treated at minority-rich instituti ons and were more often < 40 or > 60 years old. Patients who completed definitive treatment were more likely to have had

Assuntos
Carcinoma de Células Escamosas/radioterapia , Neoplasias Uterinas/radioterapia , Adulto , Negro ou Afro-Americano/estatística & dados numéricos , Carcinoma de Células Escamosas/economia , Carcinoma de Células Escamosas/etnologia , Feminino , Hispânico ou Latino/estatística & dados numéricos , Humanos , Pessoa de Meia-Idade , Radioterapia/métodos , Dosagem Radioterapêutica , Distribuição Aleatória , Fatores Socioeconômicos , Estados Unidos , Neoplasias Uterinas/economia , Neoplasias Uterinas/etnologia
8.
Ann Surg ; 230(5): 686-91, 1999 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-10561093

RESUMO

OBJECTIVE: To determine the rates of axillary lymph node dissection (ALND) and axillary irradiation (AI) in patients with breast cancer and to identify the factors influencing them. SUMMARY BACKGROUND DATA: Routine performance of ALND in the treatment of breast cancer has become controversial. AI has been proposed as an alternative to ALND, and it has been suggested that AI in addition to ALND may decrease local failure in high-risk patients. METHODS: A joint study was conducted by the Commission on Cancer of the American College of Surgeons and the American College of Radiology. A total of 17,151 patients with stage I and II breast cancer treated at 819 institutions in 1994 were studied. RESULTS: A total of 15,992 patients underwent ALND (93%). The mean ages of patients who did and did not undergo ALND were 60.4 and 73.0 years. Univariate analysis demonstrated significantly decreased rates of ALND for women age 70 or older (86% vs. 97%), patients with clinical T1 a tumors (81% vs. 93%), grade I histology (90% vs. 95%), and patients with favorable tumor types (88% vs. 94%). The ALND rate did not vary between palpable and nonpalpable tumors. Multivariate analysis of variables affecting the rate of ALND identified type of surgery, age, tumor size, histology, and payer status as significant. A total of 889 patients received AI. Patients not undergoing ALND were more likely to receive AI (10% vs. 5%). A total of 1.6% of patients with no lymph node metastasis underwent AI, 8.9% of those with one to three positive nodes underwent AI, 24.0% of those with four to nine positive lymph nodes underwent AI, and 29.9% of those with > or = 10 positive lymph nodes underwent AI. Multivariate analysis of variables affecting the proportion of patients who received AI and had undergone ALND identified nodal status and type of surgery as significant. CONCLUSIONS: Axillary lymph node dissection continues to be routinely applied in the treatment of breast cancer, and AI remains underused in patients at high risk for local regional relapse.


Assuntos
Neoplasias da Mama/radioterapia , Neoplasias da Mama/cirurgia , Excisão de Linfonodo/estatística & dados numéricos , Adulto , Idoso , Idoso de 80 Anos ou mais , Axila , Neoplasias da Mama/patologia , Feminino , Humanos , Modelos Logísticos , Metástase Linfática , Pessoa de Meia-Idade
9.
Int J Radiat Oncol Biol Phys ; 43(2): 351-8, 1999 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-10030261

RESUMO

PURPOSE: To determine the impact of research findings and evolving technology on the patterns of radiotherapy practice for patients with carcinoma of the uterine cervix. METHODS AND MATERIALS: Sixty-two radiation therapy facilities participated in the study after having been selected from a random sample, proportionally stratified according to practice type, of all United States facilities. Each facility submitted a list of patients treated during 1992-1994 with radiation for squamous carcinoma of the cervix. Cases for review were randomly selected from each institution after excluding those of patients who had distant metastases or initial hysterectomy. A total of 471 patients' records were reviewed in the treating institutions to obtain information about patients' characteristics, diagnostic evaluation, tumor extent, treatment approach, and radiotherapy techniques. RESULTS: Of the 61 facilities that treated eligible cases of intact cervical cancer during the 3-year survey period, 35 (57%) treated fewer than three eligible patients per year. Thirty-four (83%) of 41 non-academic facilities vs. 1 (5%) of 20 academic facilities treated fewer than three patients per year. FIGO stages were I, II, III, and IV in 32%, 40%, 24%, and 3% of patients, respectively. Computed tomography (CT) was the most common method of lymph node evaluation, but surgical evaluation, which was performed in 76 (16%) patients, had increased from previous surveys. Fields were designed using a dedicated simulator in 95% of patients; a dedicated CT unit was used for treatment planning in 119 (30%) cases. External beam irradiation was most often given using a four-field technique at 180 cGy per day on a 10-20 MV linear accelerator. The average daily fraction size had decreased from previous surveys, and 13% of patients were treated with daily doses of 170 cGy or less. Most patients were treated with a combination of external beam and low dose-rate (LDR) intracavitary irradiation. Of 425 patients who had treatment with curative intent that included brachytherapy, 362 (85%) had LDR brachytherapy, 45 (11%) had high dose-rate (HDR) brachytherapy, 3 had a combination of HDR and LDR, and 15 had incomplete information about the brachytherapy dose-rate. Forty-six (23%) of 197 patients with Stages I-IIA disease were treated with radiation followed by extrafascial hysterectomy. Of 111 patients treated with curative intent for Stage III-IV disease, 72 (65%) had a combination of external beam and intracavitary radiation therapy, 22 (20%) had external beam plus interstitial brachytherapy, and 17 (15%) were treated with external beam irradiation only. For patients who completed treatment with curative intent and did not have adjuvant hysterectomy or HDR brachytherapy, the median total dose at point A was 82.5 Gy. For all patients who completed treatment with radiation alone, the median total duration of treatment was 63 days; more than 70 days were taken to complete treatment in 33% of cases. Twenty-nine percent of patients received chemotherapy, usually concurrent with their radiation therapy. Only 27% of these patients were on investigational protocols. CONCLUSIONS: Greater participation in well-designed prospective trials might help clinicians address important clinical questions and reduce current inconsistencies in the use of adjuvant treatments. Radiation oncologists should take steps to avoid unnecessary treatment protraction and to improve patient compliance. Future studies will be needed to determine whether the small number of cases being treated in most nonacademic facilities will influence the outcome for patients with invasive cervical carcinoma.


Assuntos
Carcinoma de Células Escamosas/radioterapia , Padrões de Prática Médica , Radioterapia (Especialidade)/normas , Neoplasias do Colo do Útero/radioterapia , Adulto , Idoso , Braquiterapia/estatística & dados numéricos , Carcinoma de Células Escamosas/tratamento farmacológico , Carcinoma de Células Escamosas/patologia , Feminino , Pesquisas sobre Atenção à Saúde , Humanos , Histerectomia , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Dosagem Radioterapêutica , Pesquisa , Estados Unidos , Neoplasias do Colo do Útero/tratamento farmacológico , Neoplasias do Colo do Útero/patologia
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