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Tumor specimens of 203 infants with neuroblastomas of different clinical stages — registered in successive multicenter clinical trials of the German Society of Pediatric Oncology — could be examined for N-myc amplification, chromosome 1-ploidy and — structure, CD44 std. expression (in tumor tissue, and also in patients sera).Eightyseven (= 43%) of these infants had a non-localized, disseminated neuroblastoma, mainly involving sympathetic nerve tissue, lymphnodes, liver, skin, bone marrow and bones (46 patients were classified into the 4s group, 41 patients in the true 4 group).If the clinical classification between stage 4 and stage 4swas neglected, then 17 of these infants (= 20%) had N-myc amplification (4—64 copies) with 16 already dead. Seven of 9 examined patients with true stage 4 had chromosome 1p aberrations (with N-myc amplification in 5), and among the dead there were 2 with CD44 negative expression.In another series, serum CD44 std. was measured by ELISA, and the highest (significantly different) Kruskal-Wallis mean rank values (147.8) were found in infants (n = 6) with stage 4s compared to the low mean-rank-value of 71.9 in patients with stage 4 (n = 65). Stage 1—3 patients (n = 42) had values of 99.8—88.6.Thus, infants with disseminated neuroblastomas, showing non-diploidy, normal chromosome 1p structure, non-N-myc amplification and high CD44 std. expression in tumor tissue, and also high CD44 std. values in serum, will have the highest chance of survival due to tumor-non-progression.On the other hand, N-myc amplification in the tumor cells was found to be characteristic for stage 4s neuroblastoma patients with tumor progression (n=6). Therefore, 4s neuroblastoma-patients with N-myc amplified tumors should be aggressively treated like true stage 4 tumor patients!  相似文献   
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PURPOSE: The purpose of this study was to establish the feasibility and efficacy of preoperative radiotherapy (RT) with concurrent capecitabine and oxaliplatin (XELOX-RT) in patients with rectal cancer. PATIENTS AND METHODS: Thirty-two patients with locally advanced (T3/T4) or low-lying rectal cancer received preoperative RT (total dose, 50.4 Gy). Capecitabine was administered concurrently at 825 mg/m2 bid on days 1 to 14 and 22 to 35, with oxaliplatin starting at 50 mg/m2 on days 1, 8, 22, and 29 with planned escalation steps of 10 mg/m2. End points of the phase II study included downstaging, histopathologic tumor regression, resectability of T4 disease, and sphincter preservation in patients with low-lying tumors. RESULTS: Dose-limiting grade 3 gastrointestinal toxicity was observed in two of six patients treated with 60 mg/m2 of oxaliplatin. Thus, 50 mg/m2 was the recommended dose for the phase II study. Toxicities observed at this dose level were generally mild, with only two cases of short-lived grade 3 diarrhea. Myelosuppression, mainly leukopenia, was restricted to grade 2 in 19% of patients. T-category downstaging was achieved in 17 (55%) of 31 operated patients, and 68% of patients had negative lymph nodes. Pathologic complete response was found in 19% of the resected specimens. Radical surgery with free margins could be performed in 79% of patients with T4 disease, and 36% of patients with tumors < or = 2 cm from the dentate line had sphincter-saving surgery. CONCLUSION: Preoperative XELOX-RT is a feasible and well tolerated treatment. This regimen is proposed for phase III evaluation comparing standard fluorouracil-based therapy with XELOX chemoradiotherapy.  相似文献   
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Purpose To evaluate the ability of D-saccharic acid 1.4-lactone (SAL), a -glucuronidase inhibitor, to prevent irinotecan hydrochloride (CPT-11) from inducing mucosal damage as a cause of diarrhea in rats.Methods Wistar rats were divided into six groups of three animals each, administered 1.0 ml isotonic solution intraperitoneally once daily for up to three consecutive days, respectively for up to six days. The series were as follows: (1) On days 1–3: saline; (2). On days 1–3: 200 mg CPT-11/m2; (3) On days –3 to –1 relative to the first administration of CPT-11: 10 mg/ml SAL; on days 1–3: 200 mg CPT-11/m2; (4) On days –3 to +3 relative to the first administration of CPT-11: 10 mg/ml SAL, and on days 1–3: additional 200 mg CPT-11/m2; (5) On days 1–3: 200 mg CPT-11/m2 (0.5 ml) + 10 mg/0.5 ml SAL; (6) On days –3 to –1 relative to the first administration of CPT-11: 3 mg/ml SAL, and on days 1–3: 200 mg CPT-11/m2. Luminal mucosa damage of the small intestine was detected by histology 24 h after the last intraperitoneal application. Peptidase activities of the proximal jejunum were measured by using an in situ perfusion model.Results Following intraperitoneal CPT-11 treatment, using conventional histology of paraffin sections, we observed severe mucosal damage. This was reflected by a decrease of the villi/crypt ratio, an increase of apoptotic cells, as well as an increase of mitotic figures in the crypt region. There was a concomitant increased lymphatic infiltration in mucosa of CPT-11 treated rats. This damage pattern could be clearly reduced by co-treatment with the -glucuronidase inhibitor, SAL, independent of the treatment schedule. In contrast to our expectations based on previous reports, the intraperitoneal application of CPT-11 alone or in combination with SAL did not cause significant differences in luminal enzyme liberation in comparison with controls in the in situ perfusion assay.Conclusions The -glucuronidase inhibitor SAL is able to significantly reduce CPT-11-induced mucosal damage in the small intestine of rats. This observation might soon have a clinical impact for the treatment of patients with CPT-11.  相似文献   
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Summary To define the contribution of T-lymphocyte subsets in the development of aplastic anemia (AA), T-cell subpopulations including T cells, T cells, and TCS1-positive T cells, were analyzed by cytophotometry in the peripheral blood (PB) and bone marrow (BM) of patients with AA before and after 6 weeks of therapy with anti-lymphocyte globulin (ALG), methylprednisolone, and cyclosporin A (CSA). In nine patients with AA a significant decrease of PB- and BM-derived T cells was observed after 6 weeks of therapy as compared with normal controls. At diagnosis, the CD4/CD8 ratio in PB and BM of the patients did not differ from the ratio in the control population; however, a reversed ratio (< 1) was present in PB as well as in BM after weeks of therapy. Interestingly, lymphocytes expressing the T-cell receptor (TCR) were significantly decreased both before (PB 1.2±0.1%; BM 0.8±0.1%) and after 6 weeks of therapy (PB 0.7±0.1%; BM 0.7±0.1%) as compared with healthy controls (PB 2.4±0.2%; BM 2.3±0.2%). However, the proportion of the -T-cell subpopulation expressing the TCS1 phenotype was markedly increased before (PB 42±3.5%; BM 31±3%) and especially after 42 days of therapy (PB 77±12%; BM 45±2%) as compared with that in normal subjects (PB 19±2%; BM 9.7±0.8%). At present, follow-up is under evaluation to correlate these findings with hematological response. The pathophysiological significance of the observed alterations within the T-cell subsets and especially the T-cell populations will require further functional analyses, in particular since TCS1-positive T cells exhibit autoimmunological capacity.Presented at the annual meeting of the German Society for Hematology and Oncology, 4–7 October 1992, Berlin  相似文献   
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