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Purpose: Small pulmonary lesions that include ground-glass attenuation have been increasingly discovered because of progressive imaging diagnostic technologies. Despite the detection of such small lesions, sometimes it is quite difficult to localize them because of their size or considerable depth from the visceral pleura. In the present study, we examined the usefulness of computed tomography-guided lipiodol marking for thoracoscopic resection of impalpable pulmonary nodules.Methods: Fifty-six patients with an undiagnosed peripheral lesion(s) of the lung who had undergone preoperative computed tomography-guided lipiodol marking followed by video-assisted thoracoscopic surgery were studied.Results: All of the nodules were successfully marked by computed tomography-guided lipiodol marking, and all except for one case were localized by means of intraoperative fluoroscopy as clear spots. With regard to complications, pneumothorax occurred in 21 patients (37.5%), and only one patient required transient drainage. Although hemorrhaging in the lung parenchyma and hemosputum occurred in nine patients (16.1%) and one patient (1.8%), respectively, no patients were in serious condition. No intra- or postoperative mortality or morbidity was observed.Conclusion: Preoperative computed tomography-guided lipiodol marking of small or impalpable pulmonary nodules is a safe and useful procedure for thoracoscopic resection of the lung.  相似文献   
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The aim of this study was to evaluate whether the lesion regression rate (ΔLR) based on the Response Evaluation Criteria in Solid Tumors (RECIST) criteria could be used for the prediction of treatment outcome in head and neck squamous cell carcinoma (HNSCC) patients treated with chemoradiotherapy (CRT) compared with FDG PET-CT. A total of 33 patients underwent MRI and PET-CT at pretreatment and at 8 weeks after CRT. We assessed the treatment outcome by analyzing the following parameters: the RECIST criteria, ΔLR, the European Organization for Research and Treatment of Cancer (EORTC) criteria, and pretreatment SUVmax of the primary tumor and node. The correlation between the analysis of the parameters and the results of the long-term follow-up of the patients was determined. The RECIST did not significantly correlate with locoregional control (LRC) or survival. The ΔLR was significantly lower for the lesions with locoregional failure (LRF) than for those with LRC. A threshold ΔLR of 48% revealed a sensitivity of 72.7% and specificity of 77.3% for the prediction of LRF. Progression-free survival (PFS) of patients with ΔLR ≥ 48% was significantly better than that of patients with ΔLR < 48% (P = 0.001), but not overall survival. There was a significant correlation between LRC and the EORTC (P = 0.02). The patients who achieved a complete response by the EORTC criteria showed significantly better PFS and overall survival (P = 0.01 and 0.04, respectively). The ΔLR was inferior to FDG PET-CT with respect to the prediction of patient survival; however, it may be useful for selecting patients in need of more aggressive monitoring after CRT.  相似文献   
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Background: Gastrointestinal stromal tumors (GIST) are one of the most common mesenchymal tumors of the gastrointestinal tract. GIST are defined by positive immunohistochemical staining for KIT or CD34 and thus are generally diagnosed after surgery. Because small GIST are rarely diagnosed before surgery, the clinical course of these small tumors is not clear. The aim of the present study was to follow changes in size and configuration of small GIST that were pathologically confirmed using endoscopic ultrasonography‐guided fine‐needle aspiration biopsy (EUS‐FNAB). Methods: Between July 1997 and December 2003, 16 tumors in 16 patients (10 men and 6 women) with an immunohistochemical diagnosis of GIST were regularly followed in our hospital. The median patient age when EUS‐FNAB was performed was 62 years (range 26–82 years) and the median follow‐up period was 4.9 years (range 0.5–9.6 years). Results: Fourteen tumors showed no remarkable changes in size and shape during follow up compared with the initial diagnosis. Two tumors enlarged: one tumor approximately doubled its diameter in 8 years and the other tumor increased from 1.8 cm at diagnosis to up to 10 cm after only 2 years. Doubling time of the latter tumor was calculated as 3.1 months. Conclusions: We conclude that EUS‐FNAB might be a good modality for final diagnosis of GIST without surgery, and that GIST without rapid growth on follow up can be endoscopically followed.  相似文献   
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Acute tendon rupture of the extensor pollicis longus (EPL) is rare. We present acute EPL tendon rupture associated with avulsed fracture of the second metacarpal at the insertion of extensor carpi radialis longus. Tendon rupture of the EPL was repaired with end-to-end suture and avulsed fracture of the second metacarpal base was treated with open reduction and internal fixation.  相似文献   
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The direct causal relationship between dermatomyositis-polymyositis (PM) and malignancy remains controversial. We describe herein the case of a patient who underwent surgical treatment for colon cancer, which had preceded the onset of PM with tumor relapse. The PM markedly improved following the initiation of steroid therapy, and has remained under control, probably as a result of chemotherapy. The current concepts of variable clinical courses and the possible mechanism for the association of PM with malignancy are discussed following this case report.  相似文献   
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The ganglioside composition of human melanoma was analyzed in five sets of tumor specimens obtained directly from surgery, from the autologous tissue culture cell lines, and from the autologous cell lines grown in athymic nude mice. Total gangliosides of these 15 melanoma specimens were isolated and purified, and the amount of each component ganglioside was analyzed by thin-layer chromatography and a thin-layer chromatography scanner. The ganglioside composition of the five surgical melanoma specimens clearly exhibited different patterns from each other. Moreover, none of the autologous cultured melanomas possessed the same ganglioside composition as their original biopsied tumors. However, when these melanoma cell lines were transplanted into nude mice, the ganglioside composition was converted back to the same ganglioside pattern as in the original surgical specimens. The results support the view that changes in the ganglioside composition of melanoma during in vitro growth are caused by the culture environment rather than by selection of melanoma cells with a particular genotype. Reestablishment of the original ganglioside patterns after passage in nude mice provides clear evidence that in vivo expression of gangliosides is a conserved and stable function specified by the human melanoma cells.  相似文献   
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