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51.
《European journal of surgical oncology》2019,45(6):1039-1045
IntroductionMuch controversy exists over whether to perform lateral neck dissection (LND) on patients with papillary thyroid carcinoma (PTC). This study aimed to build predictive nomograms that could individually estimate lateral neck metastasis (LNM) risk and help determine follow up intensity.Patients and methodsUnifocal PTC patients who underwent LND between April 2012 and August 2014 were identified. Clinical and pathological variables were retrospectively evaluated using univariate and stepwise multivariate logistic regression analysis. Variables that had statistical significance in final multivariate logistic models were chosen to build nomograms, which were further corrected using the bootstrap resampling method.ResultsIn all, 505 PTC patients were eligible for analysis. Among these, 178 patients (35.2%) had lateral neck metastasis. Two nomograms were generated: nomogram (c) and nomogram (c + p). Nomogram (c) incorporated four clinical variables: age, tumor size, tumor site, and extrathyroidal extension (ETE). It had a good discriminative ability, with a C-index of 0.79 (bootstrap-corrected, 0.78). Nomogram (c + p) incorporated two clinical variables and two pathological variables: tumor size, tumor site, extranodal extension (ENE), and number of positive nodes in the central compartment. Nomogram (c + p) showed an excellent discriminative ability, with a C-index of 0.86 (bootstrap-corrected, 0.85).ConclusionTwo predictive nomograms were generated. Nomogram (c) is a clinical model, whereas nomogram (c + p) is a clinicopathological model. Each nomogram incorporates only four variables and can give an accurate estimate of LNM risk in unifocal PTC patients, which may assist clinicians in patient counseling and decision making regarding LND. 相似文献
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Background: Relatively few studies investigated the importance of frailty in radical cystectomy (RC) patients. We tested the ability of frailty, using the Johns Hopkins Adjusted Clinical Groups indicator, to predict early perioperative outcomes after RC.Methods: RC patients were identified within the National Inpatient Sample database (2000–2015). The effect of frailty, age and Charlson Comorbidity Index were tested in five separate multivariable models predicting: (1) complications, (2) failure to rescue (FTR), (3) in-hospital mortality, (4) length of stay (LOS) and (5) total hospital charges (THCs). All models were weighted and adjusted for clustering, as well as all available patient and hospital characteristics.Results: Of 23,967 RC patients, 5833 (24.3%) were frail, 7721 (32.2%) were aged ≥75 years and 2832 (11.8%) had CCI ≥2. Frailty, age ≥75 years and CCI ≥2 were non-overlapping in 86.3% of the cohort. Any two or three of these features were recorded in 12.4 and 1.3%, respectively. Frailty was an independent predictor of all five examined endpoints and the magnitude of its association was stronger or at least equal than that of age ≥75 years and CCI ≥2.Conclusion: Frailty, advanced age and comorbidities represent non-overlapping patients’ characteristics. Of those, frailty represents the most consistent and strongest predictor of early adverse outcomes after RC. Ideally, all three indicators should be considered in retrospective, as well as prospective analyses. Pre-surgical recognition of frail patients should be ideally incorporate in clinical practice in order to address these patients to multimodal pre-habilitation programs that may potentially improve the perioperative prognosis. 相似文献
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Lingual lymph nodes are an inconstant group of in-transit nodes, which are located on the route of lymph drainage from the tongue mucosa to the regional nodes in neck levels I and II. There is growing academic data on the metastatic spread of oral cancer, particularly regarding the spreading of oral tongue squamous cell carcinoma to lingual nodes. These nodes are not currently included in diagnostic and treatment protocols for oral tongue cancer. Combined information on surgical anatomy, clinical observations, means of detection, and prognostic value is presented. Anatomically obtained incidence of lingual nodes ranges from 8.6% to 30.2%. Incidence of lingual lymph node metastasis ranges from 1.3% to 17.1%. It is clear that lymph nodes that bear intervening tissues from the floor of the mouth should be removed to improve loco-regional control. Extended resection volume, which is required for the surgical treatment of lingual node metastasis, cannot be implied to every tongue cancer patient. As these lesions significantly influence prognosis, special efforts of their detection must be made. Reasonably, every tongue cancer patient must be investigated for the existence of lingual lymph node metastasis. Lymphographic tracing methods, which are currently implied for sentinel lymph node biopsies, may improve the detection of lingual lymph nodes. 相似文献
55.
Arg399Gln XRCC1 Polymorphism and Risk of Squamous Cell Carcinoma of the Head and Neck in Jordanian Patients 下载免费PDF全文
Ammar SobiaheEman HijaziHamzeh J Al-AmeerYazan AlmasriYazun JarrarMalek ZihlifMaha ShomafBaeth Al-Rawashdeh 《Asian Pacific journal of cancer prevention》2020,21(3):663-665
Background and objective: X-ray repair cross-complementing group1 (XRCC1) is a key protein in base excision repair and closely associated with the coordination of the base excision repair pathway. Many studies have focused on XRCC1 SNPs and have shown an associated between these SNPs and the risk of several types of cancers, including head and neck cancer. There are many single nucleotide polymorphisms XRCC1 gene (SNPs) and the most common SNP that result in amino acid substitutions is exon 10 (Arg399Gln). This study aimed to investigate the association between Arg399Gln SNP and the risk of squamous cell carcinoma of the head and neck. Material and method: Ninety nine patients with squamous cell carcinomas of the head and neck and 89 healthy adult controls were enrolled in this study. The Arg399Gln in XRCC1 allele was genotyped using polymerase chain reaction-restriction fragment length polymorphism method. Results: In the single-locus analyses, Arg399Gln SNP showed a significant association with head and neck cancer risk (p value = 0.016 and odd ratio of 1.8). On the genotype level, we applied three analysis models, namely co-dominant, dominant, and recessive genotypes. Arg/Arg homozygous major genotype was significantly (p value <0.05) associated with head and neck squamous cell carcinoma incidence with odd ratio of 2.23 and 2.24 for the co-dominant and recessive models, respectively. Conclusion: The findings indicated that Arg399Gln allele was associated with squamous cell carcinoma of the head and neck among Jordanian patients. This allele might be used as a genetic biomarker of squamous cell carcinoma of the head and neck. 相似文献
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《Drug metabolism and pharmacokinetics》2019,34(5):308-316
LC-MS quantification of drug metabolites is sometimes impeded by the availability of internal standards that often requires customized synthesis and/or extensive purification. Although isotopically labeled internal standards are considered ideal for LC-MS/MS based quantification, de novo synthesis using costly isotope-enriched starting materials makes it impractical for early stage of drug discovery. Therefore, quick access to these isotope-enriched compounds without chemical derivatization and purification will greatly facilitate LC-MS/MS based quantification. Herein, we report a novel 18O-labeling technique using metabolizing enzyme carboxylesterase (CES) and its potential application in metabolites quantification study. Substrates of CES typically undergo a two-step oxygen exchange with H218O in the presence of the enzyme, generating singly- and doubly-18O-labeled carboxylic acids; however, unexpected hydrolytic behavior was observed for three of the test compounds – indomethacin, piperacillin and clopidogrel. These unusual observations led to the discovery of several novel hydrolytic mechanisms. Finally, when used as internal standard for LC-MS/MS based quantification, these in situ labeled compounds generated accurate quantitation comparable to the conventional standard curve method. The preliminary results suggest that this method has potential to eliminate laborious chemical synthesis of isotope-labeled internal standards for carboxylic acid-containing compounds, and can be developed to facilitate quantitative analysis in early-stage drug discovery. 相似文献
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60.
《Clinical breast cancer》2020,20(6):454-461
BackgroundCoronavirus disease 2019 (COVID-19) has put a strain on regular healthcare worldwide. In the Netherlands, the national screening programs, including for breast cancer, were halted temporarily. This posed a challenge to breast cancer care, because ∼40% of cases are detected through national screening. Therefore, the aim of the present study was to evaluate the effects of the COVID-19 pandemic on the surgical care of patients with breast cancer in the Netherlands.Materials and MethodsThe present multicenter retrospective cohort study investigated the effects of COVID-19 on patients with breast cancer who had undergone surgery from March 9 to May 17, 2020. The primary endpoints were the number of surgical procedures performed during the study period, tumor characteristics, surgery type, and route of referral. The secondary endpoint was the incidence of postoperative complications during the study period.ResultsA total of 217 consecutive patients with breast cancer requiring surgery were included. We found an overall decrease in the number of patients with breast cancer who were undergoing surgery. The most significant decline was seen in surgery for T1-T2 and N0 tumors. A decline in the number of referrals from both the national screening program and general practitioners was observed. The incidence of postoperative complications remained stable during the study period.ConclusionsThe temporary halt of the national screening program for breast cancer resulted in fewer surgical procedures during the study period and a pronounced decrease in surgery of the lower tumor stages. 相似文献