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881.
PURPOSE: The survival of patients with local-regional adenocarcinoma of the esophagus or esophagogastric junction (EGJ) treated with preoperative chemoradiation is much better in patients with pathologic complete response than those with residual tumor. Some adenocarcinomas have mixed patterns, including signet-ring cell and mucinous histology, but the clinical significance of these subtypes is unknown. EXPERIMENTAL DESIGN: We studied 412 consecutive patients with esophageal or EGJ adenocarcinoma treated with chemoradiation followed by esophagectomy (193 patients) or surgery alone (219 patients). We evaluated signet-ring cell and mucinous histology in the resection and pretherapy biopsy specimens and compared clinicopathologic features with overall survival. RESULTS: The fraction of signet-ring cell and mucinous histology was similar in evaluated specimens of patients treated with preoperative chemoradiation or surgery alone (17% and 18%, respectively). The overall survival rate at 5 years of patients treated with preoperative chemoradiation was significantly better if residual signet-ring cell or mucinous histology was present in the esophagectomy specimen (63% versus 28%; P = 0.02). All 13 patients with acellular mucin pools and no residual carcinoma are still alive after an average follow-up time of 36 months. By contrast, in patients treated with surgery alone, overall survival rate was significantly worse if signet-ring cell or mucinous histology was present (14% versus 30%; P = 0.05). In multivariate analysis, overall survival was independently predicted by presence of signet-ring cell or mucinous histology (P = 0.04). CONCLUSIONS: Our study showed that patients with esophageal or EGJ adenocarcinoma who have signet-ring cell or mucinous histology benefited substantially from preoperative chemoradiation and esophagectomy.  相似文献   
882.
PURPOSE: Members of a family with hereditary gastrointestinal stromal tumors (GISTs) and a germline KIT oncogene mutation were evaluated for other potential syndrome manifestations. A tumor from the proband was analyzed to compare features with sporadic GISTs. PATIENTS AND METHODS: Members of a kindred in which six relatives in four consecutive generations comprised an autosomal dominant pattern of documented GISTs and cutaneous lesions underwent physical examination, imaging studies, and germline KIT analysis. A recurrent GIST from the proband was studied using microarray, karyotypic, immunohistochemical, and immunoblotting techniques. RESULTS: In addition to evidence of multiple GISTs, lentigines, malignant melanoma, and an angioleiomyoma were identified in relatives. A previously reported gain-of-function missense mutation in KIT exon 11 (T --> C) that results in a V559A substitution within the juxtamembrane domain was identified in three family members. The proband's recurrent gastric GIST had a 44,XY-14,-22 karyotype and immunohistochemical evidence of strong diffuse cytoplasmic KIT expression without expression of actin, desmin, or S-100. Immunoblotting showed strong expression of phosphorylated KIT and downstream signaling intermediates (AKT and MAPK) at levels comparable with those reported in sporadic GISTs. cDNA array profiling demonstrated clustering with sporadic GISTs, and expression of GIST markers comparable to sporadic GISTs. CONCLUSION: These studies provide the first evidence that gene expression and mechanisms of cytogenetic progression and cell signaling are indistinguishable in familial and sporadic GISTs. Current investigations of molecularly targeted therapies in GIST patients provide opportunities to increase the understanding of features of the hereditary syndrome, and risk factors and molecular pathways of the neoplastic phenotypes.  相似文献   
883.
Gastric cancer is one of the most important worldwide public health problems. Convincing epidemiologic and etiologic associations have been made between the development of gastric cancer and infection with Helicobacter pylori. H. pylori not only has adapted to survive within the harsh environment of the stomach but also is able to modulate and avoid endogenous immune responses. The design and creation of efficacious vaccine strategies against H. pylori requires an understanding of the complex interactions that make up mucosal immunity. An effective vaccine strategy against H. pylori has the potential to affect significantly on population health worldwide.  相似文献   
884.
PURPOSE: To develop a guideline for the use of sentinel node biopsy (SNB) in early stage breast cancer. METHODS: An American Society of Clinical Oncology (ASCO) Expert Panel conducted a systematic review of the literature available through February 2004 on the use of SNB in early-stage breast cancer. The panel developed a guideline for clinicians and patients regarding the appropriate use of a sentinel lymph node identification and sampling procedure from hereon referred to as SNB. The guideline was reviewed by selected experts in the field and the ASCO Health Services Committee and was approved by the ASCO Board of Directors. RESULTS: The literature review identified one published prospective randomized controlled trial in which SNB was compared with axillary lymph node dissection (ALND), four limited meta-analyses, and 69 published single-institution and multicenter trials in which the test performance of SNB was evaluated with respect to the results of ALND (completion axillary dissection). There are currently no data on the effect of SLN biopsy on long-term survival of patients with breast cancer. However, a review of the available evidence demonstrates that, when performed by experienced clinicians, SNB appears to be a safe and acceptably accurate method for identifying early-stage breast cancer without involvement of the axillary lymph nodes. CONCLUSION: SNB is an appropriate initial alternative to routine staging ALND for patients with early-stage breast cancer with clinically negative axillary nodes. Completion ALND remains standard treatment for patients with axillary metastases identified on SNB. Appropriately identified patients with negative results of SNB, when done under the direction of an experienced surgeon, need not have completion ALND. Isolated cancer cells detected by pathologic examination of the SLN with use of specialized techniques are currently of unknown clinical significance. Although such specialized techniques are often used, they are not a required part of SLN evaluation for breast cancer at this time. Data suggest that SNB is associated with less morbidity than ALND, but the comparative effects of these two approaches on tumor recurrence or patient survival are unknown.  相似文献   
885.
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   
886.
PURPOSE: We compared the efficacy of combination chemotherapy versus single-agent therapy in patients with advanced non-small-cell lung cancer. PATIENTS AND METHODS: A total of 561 eligible patients were randomly assigned to receive paclitaxel alone or in combination with carboplatin. RESULTS: The response rate was 17% in the paclitaxel arm and 30% in the carboplatin-paclitaxel arm (P < .0001). Median failure-free survival was 2.5 months in the paclitaxel arm and 4.6 months in the carboplatin-paclitaxel arm (P = .0002). Median survival times were 6.7 months (95% CI, 5.8 to 7.8) and 8.8 months (95% CI, 8.0 to 9.9), and 1-year survival rates were 32% (95% CI, 27% to 38%), and 37% (95% CI, 32% to 43%), respectively. The overall survival distributions were not statistically different: hazard ratio = 0.91 (95% CI, 0.77 to 1.17; P = .25). Hematological toxicity and nausea were more frequent in the combination arm, but febrile neutropenia and toxic deaths were equally low in both arms. There was no significant survival difference in elderly patients. Performance status 2 patients treated with combination chemotherapy had a better survival rate than those treated with single-agent therapy (P = .019). CONCLUSION: Combination chemotherapy improves response rate and failure-free survival compared with single-agent therapy, but there was no statistically significant difference in the primary end point of overall survival. The results in elderly patients were similar to younger patients. Performance status 2 patients had a superior outcome when treated with combination chemotherapy.  相似文献   
887.
PURPOSE: This is a phase I/IIa study to assess tolerance of gemcitabine and paclitaxel with radiotherapy in locally advanced non-small-cell lung cancer after induction chemotherapy. PATIENTS AND METHODS: Fifty-seven patients with stage III non-small-cell lung cancer were treated with cisplatin 80 mg/m2 on days 1 and 22 and gemcitabine 1,250 mg/m2 on days 1, 8, 22, and 28. Chemoradiotherapy began on day 43 as follows: cohort 1 (n = 9), gemcitabine 300 mg/m2 and paclitaxel 35 mg/m2 weekly (except week 9); cohort 2 (n = 9), gemcitabine 150 mg/m2 and paclitaxel 35 mg/m2 weekly (except week 9); cohort 3 (n = 10) and the 25 phase IIa patients, gemcitabine 300 mg/m2 and paclitaxel 135 mg/m2 every 21 days. Patients were treated with three-dimensional thoracic radiotherapy concurrently to 60 Gy. RESULTS: Weekly chemotherapy resulted in grade 4 esophageal and grade 3 or higher pulmonary toxicities. Reduction in dose density (cohort 3) led to a tolerable toxicity profile and was chosen as the phase IIa regimen. The response rate to induction was 49%, with stable disease in 40% of the patients. The response rate after consolidation therapy was 75% (94% for weekly chemotherapy v 82% for every 3 weeks). Median survival was 23 months, and 3-year survival was 45% for eligible patients. Local relapse occurred in 20% of the patients. Performance status of more than 1 predicted for poor outcome, but baseline pulmonary function did not. Dosimetric parameters including V15, V20, V30 (percent lung volume receiving > or = 15, > or = 20, and > or = 30 Gy, respectively), and mean lung dose correlated with pulmonary toxicity. CONCLUSION: Additional investigation with the 3-week schedule is warranted in patients with a good performance status based on the safety profile and preliminary efficacy data observed in this study.  相似文献   
888.
PURPOSE: This randomized study compared the results achieved by concurrent chemoradiotherapy (CRT) versus radiotherapy (RT) alone for nasopharyngeal carcinoma (NPC) with advanced nodal disease. PATIENTS AND METHODS: Patients with nonkeratinizing/undifferentiated NPC staged T1-4N2-3M0 were randomized to CRT or RT. Both arms were treated with the same RT technique and dose fractionation. The CRT patients were given cisplatin 100 mg/m2 on days 1, 22, and 43, followed by cisplatin 80 mg/m2 and fluorouracil 1,000 mg/m2/d for 96 hours starting on days 71, 99, and 127. RESULTS: From 1999 to January 2004, 348 eligible patients were randomly assigned; the median follow-up was 2.3 years. The two arms were well-balanced in all prognostic factors and RT parameters. The CRT arm achieved significantly higher failure-free survival (72% v 62% at 3-year, P = .027), mostly as a result of an improvement in locoregional control (92% v 82%, P = .005). However, distant control did not improve significantly (76% v 73%, P = .47), and the overall survival rates were almost identical (78% v 78%, P = .97). In addition, the CRT arm had significantly more acute toxicities (84% v 53%, P < .001) and late toxicities (28% v 13% at 3-year, P = .024). CONCLUSION: Preliminary results confirmed that CRT could significantly improve tumor control, particularly at locoregional sites. However, there was significant increase in the risk of toxicities and no early gain in overall survival. Longer follow-up is needed to confirm the ultimate therapeutic ratio.  相似文献   
889.
PURPOSE: To determine the incidence of second malignancies among patients with Hodgkin's lymphoma (HL) treated with autologous hematopoietic stem cell transplantation (AHSCT) compared with patients receiving conventional therapy alone and to identify potential risk factors for their occurrence. PATIENTS AND METHODS: We analyzed data on 1,732 consecutive patients with HL treated at the British Columbia Cancer Agency from 1976 to 2001, including 202 patients undergoing AHSCT. The median follow-up duration was 9.8 years for the whole cohort, 9.7 years for those patients treated with conventional therapy, and 7.8 years from AHSCT. RESULTS: The cumulative incidence of developing any second malignancy 15 years after therapy for HL was 9% (risk ratio = 3.5; P < .001); however, the incidence did not differ between those patients receiving conventional therapy alone compared with those undergoing AHSCT (10% and 8%, respectively; P = .48). In multivariate analysis, the only factor significantly associated with an increased risk of developing any second neoplasm or solid tumor was age > or = 35 years (P < .0001). An increased risk of therapy-induced acute myeloid leukemia and therapy-induced myelodysplastic syndrome was seen for patients aged > or = 35 years (P = .03) and stage III/IV (P = .04). CONCLUSION: Patients with HL are at increased risk of developing a second neoplasm. However, those patients undergoing AHSCT do not seem to be at greater risk compared with those patients receiving conventional therapy alone, at least during the first decade after therapy.  相似文献   
890.
PURPOSE: To determine the toxicity, maximal tolerated dose, and clinical and immunologic response to autologous dendritic cells pulsed with melanoma-associated antigen gp100-derived G280-9V peptide. PATIENTS AND METHODS: Twelve HLA-A*0201(+) patients with advanced melanoma were administered dendritic cells pulsed with G280-9V peptide. Cohorts of three patients were administered 5 x 10(6), 15 x 10(6), and 50 x 10(6) cells i.v. every 3 weeks for six doses according to a dose escalation scheme. Three additional patients were treated at the highest dose. No additional cytokines or therapies were coadministered. The immunogenicity of G280-9V-pulsed dendritic cells was measured by IFN-gamma ELISPOT assay, tetramer assay, and (51)Cr release assay comparing prevaccination to postvaccination blood samples. Response to treatment was assessed by Response Evaluation Criteria in Solid Tumors. RESULTS: CD8(+) immunity to the native G280 was observed in 8 (67%) patients as measured by ELISPOT and in 12 (100%) patients as measured by tetramer assay. Of the 9 patients tested, 9 (100%) had measurable high-avidity CTL activity as defined by lysis of allogeneic melanoma lines, which coexpress HLA-A*0201 and gp100. The median follow-up of the entire cohort is 43.8 months. Two (17%) partial responses were observed and 3 (25%) patients had stable disease. The median survival of the treated population was 37.6 months. At this time, three patients are alive, including one patient who continues to respond without additional treatment. CONCLUSION: The high rate of immunization as measured by three independent assays and the occurrence of clinical regression support continued investigation of G280-9V peptide as a candidate epitope in melanoma vaccine formulations.  相似文献   
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