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71.
72.
BACKGROUND: Lung carcinoma is a leading cause of cancer deaths worldwide. To better understand this disease, the authors studied genetic alterations in nonsmall cell lung carcinoma (NSCLC) and the association between genetic changes and clinical features. METHODS: Genetic alterations in 30 patients with adenocarcinoma (AC) and 39 patients with squamous cell carcinoma (SCC) were analyzed by comparative genomic hybridization. The genetic changes in patients with AC and SCC were compared and the associations of these changes with clinical features were studied. RESULTS: A gain of 3q with a minimal amplified region at 3q25.3-qter was significantly higher in patients with SCC compared with patients with AC (72% vs. 27%; P < 0.001). A gain of 20q and loss of chromosome 9 were detected more frequently in patients with AC compared with patients with SCC (P < 0.05). Gains of 5p and 20q and loss of 5q were significantly correlated with an advanced stage of NSCLC (P < 0.05). Amplification of 1q was significantly associated with NSCLC recurrence (P = 0.04). CONCLUSIONS: The results of the current study suggested that different chromosomal aberrations may contribute to the types and pathologic stages of NSCLC. 相似文献
73.
Intensity-modulated radiotherapy for early-stage nasopharyngeal carcinoma: a prospective study on disease control and preservation of salivary function 总被引:15,自引:0,他引:15
Kwong DL Pow EH Sham JS McMillan AS Leung LH Leung WK Chua DT Cheng AC Wu PM Au GK 《Cancer》2004,101(7):1584-1593
BACKGROUND: Xerostomia is a uniform complication after radiotherapy (RT) for nasopharyngeal carcinoma (NPC). Dosimetric studies suggested that intensity-modulated RT (IMRT) can spare part of the parotid glands from high-dose radiation. Disease control and salivary function after IMRT for early-stage NPC was studied prospectively. METHODS: Thirty-three patients with T1,N0-N1,M0 NPC were treated with IMRT from 2000 to 2002. The prescribed dose was 68-70 grays (Gy) in 34 fractions to gross tumor volume, 64-68 Gy to the planning target volume, and 70 Gy to enlarged cervical lymph nodes. Nineteen patients had stimulated whole salivary (SWS) flow assessment and stimulated parotid salivary (SPS) flow assessment at baseline and at 2 months, 6 months, 12 months, 18 months, and 24 months after the completion of IMRT. RESULTS: At a median follow-up of 2 years, only 1 neck failure was observed. The 2-year and 3-year local control, distant metastases-free, and overall survival rates all were 100%. The lymph node control and progression-free survival rates were 100% at 2 years and 92.3% at 3 years, respectively. The average mean dose to the parotid gland was 38.8 Gy. The SWS and SPS flow showed continuous recovery: 60% and 47.1% of patients recovered at least 25% of their baseline SPS flow and SWS flow, respectively, at 1 year after completion of IMRT, and the proportions rose to 85.7% and 71.4%, respectively, by 2 years. The pH and buffering capacity of saliva also improved with time. CONCLUSIONS: Parotid-sparing IMRT achieved good locoregional control, and there was continuous recovery of salivary flow, pH, and buffering capacity in the first 2 years after IMRT in patients with NPC. 相似文献
74.
Laboratory markers of tumor burden in nasopharyngeal carcinoma: a comparison of viral load and serologic tests for Epstein-Barr virus 总被引:4,自引:0,他引:4
Fan H Nicholls J Chua D Chan KH Sham J Lee S Gulley ML 《International journal of cancer. Journal international du cancer》2004,112(6):1036-1041
Epstein-Barr virus (EBV) is present within the tumor cells of most cases of nasopharyngeal carcinoma (NPC). Recent studies suggest that tumor burden is proportional to the level of EBV DNA in blood and that rapid blood testing can be used to guide therapeutic intervention. The relative utility of viral load vs. serology has been insufficiently studied. In our study, EBV viral load was measured by quantitative PCR using either real-time or end-point detection systems in serum samples from 124 NPC patients (93 pretreatment, 13 relapsed, 18 in remission) and 40 controls. Serologic titers against EBV early antigen were measured in the same serum samples. EBV DNA was detectable in 64 of 93 untreated NPC patients (69%; mean viral load 11,211 copies/ml), 11 of 13 relapsed NPC patients (85%; mean 53,039 copies/ml) and 0 of 18 remission patients. EBV DNA was detectable in only 1 of 40 non-NPC controls (3%). In 34 instances where paired plasma and serum samples were available for testing, both were effective sample types, and there was no significant difference between end-point and real-time methods for measuring viral load. Early antigen (EA) IgA and IgG titers were elevated in most NPC patients regardless of whether their disease was active or in remission. EBV viral load was more informative than was EA serology for distinguishing remission from relapsed disease. EBV DNA measurement appears to be a noninvasive way to monitor tumor burden after therapy. 相似文献
75.
Acute promyelocytic leukemia (APL) is the most curable subtype of AML yet it is not known to what extent newer therapies will succeed in the very elderly. Conventional chemotherapeutic induction regimens are usually too toxic for older patients, however, all trans-retinoic acid (ATRA) and arsenic trioxide (ATO) may be useful therapeutic options if used judiciously. This case series describes three octogenarians with APL all treated with ATRA and achieved complete remissions. The last patient received ATO at the time of first relapse and achieved a second remission. To our knowledge, this is the first report of successful use of ATO for induction in an octogenarian with APL. 相似文献
76.
Hu L Lau SH Tzang CH Wen JM Wang W Xie D Huang M Wang Y Wu MC Huang JF Zeng WF Sham JS Yang M Guan XY 《Oncogene》2004,23(1):298-302
The poor prognosis of hepatocellular carcinoma (HCC) has been associated with recurrence and metastasis. Recently, we established a pair of HCC cell lines from a primary (H2-P) and its matched metastatic (H2-M) HCC tumors. A high density of cDNA microarray with 9184 human cDNA was used to identify the differentially expressed genes between H2-P and H2-M. Comparing with H2-P, eight upregulated and six downregulated genes were detected in H2-M. One interesting finding is the overexpression of Vimentin (VIM), a well-defined intermediate filament, which has been linked to a more aggressive status in various tumors. The correlation of overexpression of VIM and HCC metastasis was studied by immunohistochemistry using a tissue microarray with 200 primary HCCs and 60 pairs of primary and matched metastatic HCC samples. Tissue microarray demonstrated that the overexpression of VIM was significantly associated with HCC metastasis (P<0.01). This finding strongly suggests that the overexpression of VIM may play an important role in the metastasis of HCC. 相似文献
77.
78.
Bramon E Croft RJ McDonald C Virdi GK Gruzelier JG Baldeweg T Sham PC Frangou S Murray RM 《Schizophrenia Research》2004,67(1):1-10
BACKGROUND: Mismatch negativity (MMN) is a measure of cortical activity that occurs in response to a change in auditory stimuli. We investigated whether MMN is a potential marker of genetic vulnerability to schizophrenia by comparing MMN in a group of patients with schizophrenia, their unaffected relatives, and controls. METHOD: There are 25 schizophrenic patients, 37 of their unaffected first-degree relatives, and 20 unrelated controls that performed the MMN task. Linear regression with robust standard errors, and accounting for correlations within families, was employed to test for differences in MMN amplitude between the groups. RESULTS: Patients had significantly smaller MMN amplitudes compared to both their unaffected relatives and controls at FZ (P<0.01) and at F3 (P=0.01), whereas relatives and controls did not differ at FZ or at F3. No differences were found between any of the groups at F4. Furthermore, we found no strong evidence that the MMN amplitude is a familial trait. CONCLUSIONS: Our results confirm that the MMN amplitude is reduced in schizophrenia. However, the MMN does not show a significant familial influence and is normal among the unaffected relatives. We conclude that while the MMN is abnormal in patients with schizophrenia, it is a weak or unreliable marker of vulnerability when applied to subclinical populations, and therefore is unlikely to be an endophenotype for the disorder. 相似文献
79.
McDonald C Bullmore ET Sham PC Chitnis X Wickham H Bramon E Murray RM 《Archives of general psychiatry》2004,61(10):974-984
CONTEXT: For more than a century, it has been uncertain whether or not the major diagnostic categories of psychosis--schizophrenia and bipolar disorder--are distinct disease entities with specific genetic causes and neuroanatomical substrates. OBJECTIVE: To investigate the relationship between genetic risk and structural variation throughout the entire brain in patients and their unaffected relatives sampled from multiply affected families with schizophrenia or bipolar disorder. DESIGN: Analysis of the association between genetic risk and variation in tissue volume on magnetic resonance images. SETTING: Psychiatric research center. PARTICIPANTS: Subjects comprised 25 patients with schizophrenia, 36 of their unaffected first-degree relatives, 37 patients with bipolar 1 disorder who experienced psychotic symptoms during illness exacerbation, and 50 of their unaffected first-degree relatives. MAIN OUTCOME MEASURES: We used computational morphometric techniques to map significant associations between a continuous measure of genetic liability for each subject and variation in gray or white matter volume. RESULTS: Genetic risk for schizophrenia was specifically associated with distributed gray matter volume deficits in the bilateral fronto-striato-thalamic and left lateral temporal regions, whereas genetic risk for bipolar disorder was specifically associated with gray matter deficits only in the right anterior cingulate gyrus and ventral striatum. A generic association between genetic risk for both disorders and white matter volume reduction in the left frontal and temporoparietal regions was consistent with left frontotemporal disconnectivity as a genetically controlled brain structural abnormality common to both psychotic disorders. CONCLUSIONS: Genetic risks for schizophrenia and bipolar disorder are associated with specific gray matter but generic white matter endophenotypes. Thus, Emil Kraepelin's pivotal distinction was neither wholly right nor wholly wrong: the 2 major psychoses show both distinctive and similar patterns of brain structural abnormality related to variable genetic risk. 相似文献
80.
PURPOSE: To evaluate the changes in olfactory function in patients with nasopharyngeal carcinoma who have received radiation to the head and neck. MATERIALS AND METHODS: Olfactory function of consecutive patients with nasopharyngeal carcinoma was assessed prospectively before irradiation and serially up to 1 year after radiotherapy by the Sniffin' Sticks (Erlangen, Germany) olfactory function test and by a patient symptom visual analogue scale. RESULTS: Fifty-eight patients were recruited before radiotherapy was commenced. Three patients could not give a reliable response to the Sniffin' Sticks test even in this first assessment, and 7 patients did not return for evaluation after irradiation. Forty-eight patients were available for follow-up assessment. Mean olfactory threshold scores by the Sniffin' Sticks test were found to deteriorate significantly at 12 months when compared with the scores before irradiation (8.3 at 12 months vs 11.5 before irradiation; P =.001). Scores for olfactory discrimination and for identification did not exhibit any significant changes when assessed at 12 months (P >.05 for both). Subjective patient assessment of olfactory function with the visual analogue scale at 12 months did not demonstrate any significant differences when compared with patients' assessment before irradiation (P =.90). An increase in discharge was the only nasal symptom that demonstrated a significant change at 12 months when compared with the assessment before irradiation (P < 001). CONCLUSIONS: Deterioration in olfactory threshold scores was found at 12 months after irradiation and was not noticed by the patients. 相似文献