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81.
PURPOSE: Constitutive mutational activation of c-kit has been found to be associated with the pathogenesis of gastrointestinal stromal tumors (GISTs). The prognostic significance of c-kit mutations, however, is still controversial. EXPERIMENTAL DESIGN: We examined 86 patients curatively resected for localized GIST. Genomic DNA was extracted from paraffin-embedded tumor tissues. Exons 9, 11, 13, and 17 of the c-kit gene were amplified by PCR and sequenced. RESULTS: Mutations in exon 11 were detected in 61 tumors, and mutations in exon 9 were observed in three tumors, whereas no mutations were detected in exons 13 or 17. The overall c-kit mutation frequency was 74%. Amino acid alterations in the 61 tumors with exon 11 mutations were deletion in 33 tumors, substitution in 20, both deletion and substitution in 4, insertion in 1, and duplication in 3. Histologically, tumors with c-kit mutations showed higher mitotic counts and higher cellularity. The 5-year relapse-free survival (RFS) in patients having GISTs with c-kit mutations was 21%, compared with 60% in those without c-kit mutations. Significantly higher RFS rates were observed in patients with tumors having mitotic counts < 5 mitoses/50 high power field, spindle-cell histology, tumor size < 5 cm, or gastric GISTs. Multivariate analyses indicated association of poorer RFS with a higher mitotic count > or = 5 of 50 high power fields; odds ratio (OR) = 3.0], presence of c-kit mutations (OR = 5.6), and a larger tumor size (> or = 5 cm; OR = 4.2). CONCLUSIONS: The presence of c-kit mutation, along with high mitotic count and larger tumor size, was an independent factor for poor prognosis in patients with localized GISTs.  相似文献   
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PURPOSE: We hypothesized that the outcome of liver transplantation in patients with hepatocellular carcinoma (HCC) has improved over the past decade because of the application of published criteria for patient selection. In this study, we compared the outcome of liver transplantation in patients with and without HCC at different time periods using the United Network for Organ Sharing data. PATIENTS AND METHODS: We excluded children, patients with multiple organ transplantation or retransplantation, and those with incomplete survival data. The study period was arbitrarily divided into three time intervals: 1987 to 1991, 1992 to 1996, and 1997 to 2001. RESULTS: During the study period, 985 patients with HCC (HCC group), and 33,339 without HCC underwent liver transplantation (control group). Kaplan-Meier patient and graft survivals were significantly lower for the HCC group compared with the control group. Cox regression analysis (after adjusting for other confounding variables) confirmed a lower patient survival in the HCC group (1-year survival, 77.0% v 86.7%; hazard ratio [HR], 1.7; 95% CI, 1.5 to 2.0; P <.0001) compared with the control group (5-year survival, 48.2% v 74.7%; HR, 2.2; 95% CI, 1.9 to 2.4; P <.0001); HCC was an independent predictor of survival. Kaplan-Meier analysis showed a significant improvement in 5-year patient survival with time in patients with HCC (1987 to 1991, 25.3%; 1992 to 1996, 46.6%; 1997 to 2001, 61.1%; P <.0001). During the same period, there was only minimal improvement in survival among the control group. CONCLUSION: Five-year survival of patients transplanted for HCC is excellent, with a steady improvement in survival over the past decade. It is possible that the published criteria for patient selection may have contributed to the better outcome.  相似文献   
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三才注射液对小鼠红系细胞的影响   总被引:4,自引:0,他引:4  
目的:探讨三才封髓丹对小鼠红系细胞造血的作用机理。方法:通过应用三才注射液对贫血及正常小鼠外周血的Hb、RBC、网织红细胞(Ret)、红系分裂指数、骨髓有核细胞(BMC)进行测定及采用红系造血祖细胞的培养方法,观察三才封髓丹的造血作用。结果:三才封髓丹能促进贫血小鼠的Hb、RBC、Ret、红系分裂指数、BMC的增加,在脾细胞或腹腔巨噬细胞条件下,能促进BFU-E及CFU-E的增殖。结论:三才封髓丹  相似文献   
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Relapsed or refractory acute myeloid leukemia (R/R AML) in elderly (≥60 yr old) patients were eligible. Induction chemotherapy consisted fludarabine and cytarabine (ARAC) as a 24‐hr CI without idarubicin (C‐FLAG), which was compared with the results of C‐FLAG with idarubicin (CI‐FLAG2) in younger patients’ trial. A total of 33 and 68 patients were enrolled in C‐FLAG and CI‐FLAG2, respectively. CR, CRp, and CRi were achieved in 10 (30.3%), 3 (9.1%), and 2 (6.1%), respectively. When comparing outcomes between C‐FLAG and CI‐FLAG2, there were no difference in terms of CR rate (P = 0.572) and objective response rate (ORR; P = 0.899). Favorable predictors on ORR in C‐FLAG were PB WBC ≤ 20K/uL at salvage (P = 0.024) and early evaluation peripheral BLAST = 0% (P = 0.013) on multivariate analysis. The overall survival of patients who achieve CR/CRp/CRi showed significantly prolonged survival compared with patients who did not in C‐FLAG (P < 0.001) and was a favorable predictor of longer survival by multivariate analysis (P = 0.009). Median overall survival was 3.19 (95% CI, 2.05–4.33) months and similar with that of CI‐FLAG2 (P = 0.841). Attenuated salvage regimen C‐FLGA in elderly patients was as effective as more intensive younger patients’ regimen CI‐FLAG2 in terms of response and survival although elderly patients had more unfavorable clinical characteristics.  相似文献   
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This study describes a retrospective analysis on the transplant outcome of 56 consecutive patients with myelodysplastic syndrome (MDS) according to their response to hypomethylating agents (HMA). While 2‐yr disease‐free survival (DFS) of patients who transformed to acute myeloid leukemia (= 12) was 25%, that of the remaining patients with MDS according to response to HMA was 73.1%, 68.1%, 50.0%, and 20.8% in G‐COR (group of continuous response, = 19), G‐NoC (group of no change, = 15), G‐LOR (group of loss of response, = 6), and G‐DP (group of disease progression, = 4), respectively. When dichotomized as G‐COR/G‐NoC versus G‐LOR/G‐DP, significantly different 2‐yr DFS (71.0% vs. 33.3%; = 0.004) and relapse (14.1% vs. 46.7%; = 0.016) were demonstrated. On multivariate analysis, G‐LOR/G‐DP [hazard ratio (HR), 3.91; = 0.008] and poor karyotype at transplantation (HR, 2.69; = 0.017) were the significant predictors for poor DFS, as G‐LOR/G‐DP was for relapse (HR, 6.28; = 0.011). DFS was significantly poor in patients with any of the two predictors in all MDS (81.5% vs. 34.9%; = 0.001) or higher‐risk MDS (HrMDS) at the time of HMA (80.7% vs. 29.2%; = 0.005). G‐COR showed a trend of better DFS compared with G‐NoC among HrMDS (74.6% vs. 36.5%; = 0.090). These results implicate the significance of response to HMA on hematopoietic stem cell transplantation (HSCT) outcomes and support the need for future study to verify the suggested strategy of proceeding to transplantation before LOR or DP, especially for HrMDS.  相似文献   
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