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981.
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984.
PURPOSE: To investigate whether allogeneic stem-cell transplantation (allo-SCT) may overcome the negative impact of unmutated VH genes in the outcome of patients with chronic lymphocytic leukemia (CLL). PATIENTS AND METHODS: We analyzed the outcome of patients who underwent SCT according to their VH mutational status. RESULTS: Thirty-four patients (14 allo-SCT and 20 autologous SCT [auto-SCT]) presented unmutated VH genes and 16 patients presented mutated VH genes (nine allo-SCT and seven auto-SCT). Tumoral burden pre-SCT was significantly higher in the allo-SCT patients independent of the VH mutational status. The risk of relapse was significantly higher after auto-SCT (5-year risk, 61%; 95% CI, 44% to 84%) than after allo-SCT (5-year risk 12%, 95% CI, 3% to 44%; P < .05). In the unmutated group, 13 of 20 auto-SCT and two of 14 allo-SCT patients experienced disease progression, with a risk of relapse at 5 years of 66% (95% CI, 48% to 93%) v 17% (95% CI, 5% to 60%), respectively (P = .01). CONCLUSION: These results show that allo-SCT may overcome the unfavorable effect of unmutated VH genes in patients with CLL.  相似文献   
985.
PURPOSE: To determine the activity of decitabine, a DNA methylation inhibitor, in imatinib-refractory or intolerant chronic myelogenous leukemia. MATERIALS AND METHODS: Thirty-five patients were enrolled in this phase II study (12 in chronic phase, 17 in accelerated phase, and six in blastic phase). Decitabine was administered at 15 mg/m2 intravenously over 1 hour daily, 5 days a week for 2 weeks. DNA methylation was measured using a LINE1 bisulfite/pyrosequencing assay. RESULTS: Complete hematologic responses were seen in 12 patients (34%) and partial hematologic responses in seven patients (20%), for an overall hematologic response rate of 54% (83% in chronic phase, 41% in accelerated phase, and 34% in blastic phase). Major cytogenetic responses were observed in six patients (17%), and minor cytogenetic responses were seen in 10 patients (29%) for an overall cytogenetic response rate of 46%. Median response duration was 3.5 months (range, 2 to 13+ months). Myelosuppression was the major adverse effect, with neutropenic fever in 28 (23%) of 124 courses of therapy. LINE1 methylation decreased from 71.3% +/- 1.4% (mean +/- standard error of the mean) to 60.7% +/- 1.4% after 1 week, 50.9% +/- 2.4% after 2 weeks, and returned to 66.5% +/- 2.7% at recovery of counts (median, 46 days). LINE1 methylation at the end of week 1 did not correlate with subsequent responses. However, at day 12, the absolute decrease in methylation was 14.5% +/- 3.0% versus 26.8% +/- 2.7% in responders versus nonresponders (P = .007). CONCLUSION: Decitabine induces hypomethylation and has clinical activity in imatinib refractory chronic myelogenous leukemia. We hypothesize that the inverse correlation between hypomethylation 2 weeks after therapy and response is due to a cell death mechanism of response, whereby resistant cells can withstand more hypomethylation.  相似文献   
986.
It has been suggested that expression of anti-apoptotic proteins such as Bcl-2 or BAG-1 may confer cellular resistance to chemotherapy. A corollary of this hypothesis is that expression of these proteins may predict clinical response to treatment and that Bcl-2- or BAG-1-positive cells may selectively be enriched in postchemotherapy tissue specimens. The goal of this exploratory pilot study was to assess these two predictions by using immunohistochemistry in 29 paired pre- and postchemotherapy breast tissue specimens obtained from patients who underwent preoperative doxorubicin-based chemotherapy. All breast cancers expressed BAG-1 protein, and, in individual tumors, 40-100% of neoplastic cells stained positive for this protein. Homogenous cytoplasmic staining was typically observed, though neoplastic cells also showed nuclear staining in many specimens. We found no correlation between prechemotherapy expression of BAG-1 and subsequent pathological response to cytotoxic therapy. Paired pre- and posttreatment specimens showed similar levels of BAG-1 expression when residual tumor could be assessed. Bcl-2 was expressed in 55% of cancers and was localized to the cytoplasm. Absence of Bcl-2 expression in prechemotherapy specimens was associated with more frequent complete pathological response (58% vs. 20%; p = 0.04). However, similar to BAG-1, no difference between pre- and posttherapy expression of Bcl-2 was observed in neoplastic cells in paired tissue specimens. These observations suggest that BAG-1 contributes an important cellular function to breast epithelial cells, which is reflected by its ubiquitous expression in these tissues. However, it does not appear to determine response to doxorubicin-based chemotherapy. In contrast, lack of Bcl-2 expression was associated with a higher probability of complete pathological response to doxorubicin-based chemotherapy.  相似文献   
987.
Referrals to genetics services are becoming increasingly common for patients who are diagnosed with early-onset colorectal cancer (CRC) or patients who have a family history of CRC. Microsatellite instability (MSI) testing and immunohistochemical analysis (IHC) of the patient’s tumor tissue, which assess indirectly the cellular status of DNA mismatch repair, have proven important tools for geneticists and genetic counselors to determine whether or not these individuals may be at risk for an inherited cancer syndrome, Lynch syndrome (a subset of hereditary nonpolyposis colorectal cancer). The application of tumor MSI/ IHC also extends to the group of providers involved in the diagnosis and management of CRC, demonstrating the growing clinical applicability of MSI/IHC testing. This review discusses the clinical utility of MSI/IHC analysis, including its benefits and limitations, and addresses some of the current debates surrounding testing.  相似文献   
988.
PURPOSE: Evaluate efficacy and toxicity of bortezomib in patients with relapsed or refractory B-cell non-Hodgkin's lymphoma. PATIENTS AND METHODS: Patients were stratified, based on preclinical data, into arm A (mantle-cell lymphoma) or arm B (other B-cell lymphomas) without limitation in number of prior therapies. Bortezomib was administered as an intravenous push (1.5 mg/m2) on days 1, 4, 8, and 11 every 21 days for a maximum of six cycles. RESULTS: Sixty patients with a median number of prior therapies of 3.5 (range, one to 12 therapies) were enrolled; 33 patients were in arm A and 27 were in arm B, including 12 diffuse large B-cell lymphomas, five follicular lymphomas (FL), three transformed FLs, four small lymphocytic lymphomas (SLL), two Waldenstrom's macroglobulinemias (WM), and one marginal zone lymphoma. In arm A, 12 of 29 assessable patients responded (six complete responses [CR] and six partial responses [PR]) for an overall response rate (ORR) of 41% (95% CI, 24% to 61%), and a median time to progression not reached yet, with a median follow-up of 9.3 months (range, 1.7 to 24 months). In arm B, four of 21 assessable patients responded (one SLL patient had a CR, one FL patient had a CR unconfirmed, one diffuse large B-cell lymphoma patient had a PR, and one WM patient had a PR) for an ORR of 19% (95% CI, 5% to 42%). Grade 3 toxicity included thrombocytopenia (47%), gastrointestinal (20%), fatigue (13%), neutropenia (10%), and peripheral neuropathy (5%). Grade 4 toxicity occurred in nine patients (15%), and three deaths from progression of disease occurred within 30 days of withdrawal from study. CONCLUSION: Bortezomib showed promising activity in relapsed mantle-cell lymphoma and encouraging results in other B-cell lymphomas. Future studies will explore bortezomib in combination with other cytotoxic or biologic agents.  相似文献   
989.
Purpose To compare the quality-of-life (QoL) and psycho-social changes in a group of patients with early breast cancer who underwent conservative surgery (BCS) or modified radical mastectomy (MRM). Methods Self-administered questionnaire assessing body image perception, social habits, sexual attraction and self-consciousness with relatives/friends, was randomly assigned to 125 patients (61 BCS, 64 MRM; aged 53±8 and 50±9 years, respectively, p=NS). Results MRM patients reported a significantly higher frequency of changes in body image perception and other related social behaviour such as avoiding going to the beach or using low-cut clothes, and reticence with friends. Conversely, no differences were found regarding sexuality, denial of the disease by the husband/partner, or concealing the disease from family members. Also, no significant differences were found between patients above and below the age of 50 years, for all variables studied after adjustment for surgical procedure. Conclusions Modified radical mastectomy has a negative effect on body image perception and in social behaviour patterns of patients and with a concomitant decrease in QoL. The sexuality of the patient is not significantly affected.  相似文献   
990.
The vast majority of new cases of colorectal cancer, the second most common cause of death in men and women in the United States, are attributable to environmental rather than genetic causes. Recent research has clarified inconsistencies in the literature and has explored new pathways through which risk factors may act. This review discusses newly published, selected interesting and important findings in colorectal cancer etiology; these include postmenopausal hormone use, nonsteroidal anti-inflammatory drug use, obesity, physical activity, diet, and other confirmed epidemiologic associations. This research provides insight into mechanisms and offers opportunities for prevention.  相似文献   
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