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71.
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73.

Purpose

To explore the possibility of targeted biopsy (TBx) using transrectal ultrasound (US) with perflubutane microbubbles, we studied the findings of different cancerous tissue imaging modalities and evaluated needle biopsy in prostate cancer (PCa) using contrast-enhanced US (CEUS) in a multicenter clinical trial.

Methods

Seventy-one patients undergoing prostate biopsy received intravenous injection of perflubutane microbubbles (Sonazoid®). We evaluated and compared images obtained by CEUS. The safety observation period was 2 days after contrast administration.

Results

Among the 30 patients with cancer, one or more sites with findings suggestive of cancer in CEUS were detected in 23 patients (32.4%) by TBx. Although 22 patients had positive cores of cancer by systematic biopsy (SBx), 8 patients had positive cores of cancer in TBx alone (11.3%). There was a significant difference in cancer detection rate by TBx between two cohorts with PSA < 10 ng/mL (22.9%) and PSA ≥ 10 ng/mL (52.2%) (P < 0.02). Close observation of various CEUS findings with Sonazoid® enabled targeting of cancerous areas, and consequently, a significant difference (P < 0.05) in the detection rate of cancer was recognized in the transition zone (TZ): SBx; 21/120 (17.5%) and TBx; 17/55 (30.9%). The incidence of adverse events was 6.7% and that of adverse reactions was 4%.

Conclusions

CEUS with Sonazoid® improved the detection rate of PCa by visualizing cancerous lesions. More detailed examination of CEUS images provided efficient characterization especially in the TZ area. TBx according to this procedure is expected to enable a lower number of biopsies and more accurate diagnosis of PCa.  相似文献   
74.
ABSTRACT

Objective: Adult patients with ischemic moyamoya disease (MMD) who receive treatment with antiplatelet drugs reportedly show improvements in neuropsychological test scores after around 2 years. The purpose of the present study subanalyzing the same patient cohort used in a previous study was to determine which antiplatelet drug, clopidogrel or cilostazol, results in better improvement of cognitive function among non-surgical adult patients showing ischemic MMD without severe hemodynamic compromise.

Methods: Sixty-six patients without cerebral misery perfusion on 15O gas positron emission tomography were treated with pharmacotherapy alone. Patients ≥50 years old and <50 years old initially received clopidogrel and cilostazol, respectively. Any patient suffering side effects of the antiplatelet drug switched to the other antiplatelet drug. Neuropsychological tests were performed at study entry and at the end of the 2-year follow-up, and differences in each neuropsychological test score between the two time points (second test score – first test score) were calculated and defined as Δ scores.

Results: Among the five neuropsychological tests, Δ scores for two tests were significantly greater in patients treated with cilostazol (n = 36) than in those treated with clopidogrel (n = 30), and Δ scores of the remaining three tests did not differ between patient groups. Based on Δ scores, 15 patients (23%) were defined as showing interval cognitive improvement. On multivariate analysis, cilostazol administration (95% confidence interval, 1.19–193.98; P = 0.0361) represented an independent predictor of interval cognitive improvement.

Conclusions: Cilostazol may improve cognition better than clopidogrel in non-surgical adult patients with ischemic MMD.  相似文献   
75.
To establish an optimal categorization of cancer deposits without lymph node structure (extranodal cancer deposits [EX]) in a prognostic staging system, we analyzed 1,027 cases in which patients underwent potentially curative surgery for advanced colorectal adenocarcinoma. EX was classified as vascular invasion-type (VAS) or non-VAS.A total of 512 foci of EX were identified in 205 patients (20.0%), with VAS and non-VAS found in 68 and 182 patients, respectively. The hazard ratio for patients with nodal involvement was 3.6 and for patients with VAS and non-VAS, 2.5 and 4.7, respectively. Based on multivariate analysis of these 3 parameters, only nodal involvement and non-VAS were significant prognosticators. By using the Akaike information criterion, N staging was capable of predicting survival outcome with the highest accuracy when both nodal involvement and non-VAS were treated together as an N factor and VAS was treated as a T factor ("new categorization"). The clinical significance of the TNM grading system for colorectal cancer would be enhanced if we treat EX as a new categorization.  相似文献   
76.
Annals of Surgical Oncology - Colorectal cancer (CRC) is a major cause of cancer-related deaths. Metastasis is enhanced through epithelial-mesenchymal transition (EMT), a process primarily induced...  相似文献   
77.
78.

Background

Neoadjuvant chemotherapy (NACT) improves the prognosis of patients with esophageal cancer who respond, but it is not effective in nonresponders. Therefore, it is crucial to establish a reliable method of predicting response before initiation of chemotherapy. Hypercoagulability, which is thought to be because of upregulation of tissue factor (TF) in cancer cells, was reported to be associated with chemoresistance. The aim of this study was to investigate the association between TF expression and response to NACT in esophageal cancer.

Methods

In 67 patients with advanced esophageal cancer, TF expression in pretreatment biopsy samples was evaluated immunohistochemically and correlated with clinicopathologic factors and response to chemotherapy.

Results

TF was expressed by 43.3% of the tumors, but there were no correlations observed with any clinicopathologic parameters examined. Clinical and histologic responses to chemotherapy were significantly worse in TF-positive patients compared with TF-negative patients. Multivariate analysis revealed that TF expression was significantly associated with a poor clinical response (P = 0.0431). TF expression was also independently associated with poor progression-free survival (P = 0.0353).

Conclusions

TF expression levels in pretreatment biopsy samples are useful for predicting response to NACT in advanced esophageal cancer. Further studies of mechanisms underlying the relationship between TF expression and chemosensitivity are needed.  相似文献   
79.

Background

N-Acetylglucosaminyltransferase V (GnT-V), an enzyme that catalyzes the β1-6 branching of N-acetylglucosamine on asparagine-linked oligosaccharides of cellular proteins, enhances the malignant behaviors of carcinoma cells in experimental models. The aim of this study was to determine clinical significance of GnT-V expression in human pT2 gallbladder carcinoma with simple in vitro experiments.

Methods

Ninety patients with pT2 gallbladder carcinoma were included for this study. The in vitro and in vivo biological effects of GnT-V were investigated using gallbladder carcinoma cells with variable GnT-V expression levels induced by a small interfering RNA.

Results

Of the 90 cases, 57 showed positive staining and the remaining 33 demonstrated negative staining, the subcellular localization in the 57 cases was classified into the granular-type in 31 cases and the diffuse-type in 26 cases. In 76 cases with curative resection, postsurgical survival was significantly poorer in those showing positive staining than in those showing negative staining (P = 0.028). In all of the 76 cases, postsurgical recurrence was significantly more frequent in those showing diffuse-type localization than in those showing negative staining. Experimental analyses demonstrated that the down-regulation of GnT-V expression in gallbladder carcinoma cells induced suppression of cell growth in vitro. The expression levels of GnT-V in the cells were highly correlated with the rapid in vivo growth coupled with the enhanced angiogenesis, and the tendency to form liver metastasis.

Conclusions

GnT-V expression in the subserosal layer of pT2 gallbladder carcinoma is correlated with the aggressiveness of the disease.  相似文献   
80.
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