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261.
PURPOSE: Adjuvant chemotherapy for breast cancer has been the routine practice in the past decade. A number of studies have observed an increased incidence of treatment-related leukemias following chemotherapy with alkylating agents and/or topoisomerase II inhibitors. We evaluated the incidence of treatment-related leukemias in breast cancer patients treated in four adjuvant and two neoadjuvant chemotherapy trials at The University of Texas M.D. Anderson Cancer Center. PATIENTS AND METHODS: Between 1974 and 1989, 1,474 patients with stage II or III breast cancer were treated in six prospective trials of adjuvant (n = 4) or neoadjuvant (n = 2) chemotherapy with fluorouracil, doxorubicin, and cyclophosphamide (CTX) (FAC) with or without other drugs. The median observation time was 97 months. In 1,107 patients, FAC chemotherapy was given postoperatively; 367 patients received induction chemotherapy, as well as postoperative chemotherapy. Eight hundred ten patients had surgery followed by radiotherapy and chemotherapy; 664 patients had surgery and chemotherapy only. Patients in two adjuvant and one neoadjuvant study received higher cumulative doses of CTX compared with those in the other studies. RESULTS: Fourteen cases of leukemia were observed. Twelve of these patients had received radiotherapy and chemotherapy, and two had received chemotherapy only. Six of the reported patients with leukemia were treated with a cumulative CTX dose of greater than 6 g/ m2. Five of these patients had received both radiotherapy and chemotherapy. The median latency period in the 14 patients was 66 months (range, 22 to 113). Six of 10 patients with adequate cytogenetic analyses had abnormalities that involved chromosomes 5 and/or 7. The rest of the patients had nonspecific cytogenetic abnormalities or lacked cytogenetic information. The 10-year estimated leukemia rate was 1.5% (95% confidence interval [CI], 0.7% to 2.9%) for all patients treated, 2.5% (95% CI, 1.0% to 5.1%) for the radiotherapy-plus-chemotherapy group, and 0.5% (95% CI, 0.1% to 2.4%) for the chemotherapy-only group; this difference was statistically significant (P = .01). The 10-year estimated leukemia risk for the higher-dose (> 6 g/m2) CTX group was 2% (95% CI, 0.5% to 5.0%) compared with 1.3% (95% CI, 0.4% to 3.0%) for the lower-dose group, a difference that was not statistically significant (P = .53). CONCLUSION: These data illustrate that patients treated with adjuvant FAC chemotherapy plus radiotherapy have a slightly increased risk of leukemia. This information needs to be considered in the treatment plans for patients with breast cancer. However, for most patients, the benefits of adjuvant therapy exceed the risk of treatment-related leukemia.  相似文献   
262.
BACKGROUND: Metastatic breast cancer in elderly patients is less often treated with chemotherapy than in younger patients because of concerns related to toxic effects and tolerance. This is especially the case with doxorubicin-containing regimens. METHODS: We conducted a retrospective study of 1011 consecutive patients with metastatic breast cancer treated with doxorubicin-based chemotherapy protocols between July 1973 and July 1984. Age was not an exclusion criterion. Patient characteristics, dose intensity, hematologic-related toxic effects, and the cause of death were analyzed. The Kaplan-Meier survival curves were plotted and tested by the generalized Wilcoxon test. RESULTS: Seven hundred sixty-seven patients aged between 50 and 64 years were identified. While the response rate was higher in the younger group, the overall survival curves were similar for the two groups (P = .06), as well as the time to progression of the disease (P = .15). The dose intensity was comparable between the groups (P = .49), as was the median platelet and white blood cell nadirs. Neutropenic fever occurred in 16% of each group (P = 83), and fever in 12% and 17% of each group, respectively (P = .05). Death from infections occurred in 3.1% and 3.2% of patients in the two groups, respectively (P = .82). CONCLUSION: Patients with metastatic breast carcinoma who are older than 65 years tolerate the acute side effects of doxorubicin-based combination chemotherapy as well as the younger age group. Time to progression of disease and the overall survival are similar for both groups. Doxorubicin-based regimens are safe and effective for patients older than 65 years.  相似文献   
263.
A 24-kDa recombinant protein from Trypanosoma cruzi (rTc24) was evaluated by enzyme-linked immunosorbent assay (ELISA) and Western blot (immunoblot) tests to identify treated chagasic patients considered parasitologically cured on the basis of persistently negative tests of hemocultures and lytic antibodies. Some of these patients were termed dissociated because their sera, although negative by the complement-mediated lysis test, were positive by conventional serology. The negative lysis test indicates the absence of active infection after specific treatment, but this assay requires live and infectious parasites and cannot be used easily in a laboratory routine. Here we tested rTc24 by ELISA and Western blotting as an alternative for the complement-mediated lysis test. For the group of patients with active infection despite the treatment (uncured patients), all the sera tested recognized rTc24 in both tests. For the dissociated patients, approximately 80% of the sera did not react with rTc24 in the ELISA or in Western blots, in agreement with the negative complement-mediated lysis tests. Thus, the 24-kDa T. cruzi recombinant antigen, when used for initial trials to evaluate cure of chagasic patients submitted to specific treatment, will allow the identification of most, but not all, cases.  相似文献   
264.
BACKGROUND: This study was performed to validate the prognostic significance of residual axillary lymph node metastases in patients with locally advanced breast cancer (LABC) treated with neoadjuvant chemotherapy and to analyze other clinicopathologic factors that might be independent predictors of disease-free survival (DFS) in an attempt to identify patients in whom axillary dissection might be omitted. METHODS: One hundred sixty-five assessable patients with LABC were treated in a prospective trial of neoadjuvant chemotherapy utilizing four cycles of 5-fluorouracil, doxorubicin, and cyclophosphamide. Responding patients were treated with segmental mastectomy and axillary dissection or modified radical mastectomy. Patients subsequently received additional chemotherapy followed by irradiation of the breast or chest wall and draining lymphatics. The median follow-up was 35 months. RESULTS: Clinical tumor response to neoadjuvant chemotherapy (P = 0.046) and the number of residual metastatic axillary lymph nodes found at axillary dissection (P = 0.05) were the only independent predictors of DFS. Patients with a complete clinical response had a predictably excellent DFS and those with no change or progressive disease had a poor DFS. In patients with a partial response, the number of residual metastatic lymph nodes further stratified patients with respect to DFS (P = 0.006). CONCLUSIONS: Clinical response and residual metastatic axillary lymph nodes following neoadjuvant chemotherapy are important predictors of DFS. Patients with a clinically positive axilla following neoadjuvant chemotherapy should undergo axillary dissection to ensure local control. However, the benefit of axillary dissection in patients with a clinically negative axilla may be minimal if the axilla will be irradiated, and histologic staging does not affect subsequent systemic treatment. A prospective randomized trial of axillary dissection versus axillary radiotherapy in patients with a clinically negative axilla following neoadjuvant chemotherapy is presently under way to evaluate this hypothesis.  相似文献   
265.
Iron sucrose and low-molecular-weight iron dextran (LMW-ID), two commonly used iron solutions, have been compared in terms of allergic adverse event profiles to date. However, the safety of total dose infusion of LMW-ID has been investigated by only one study in chronic kidney disease (CKD) (not dialysis) patients. Thus, we aimed to compare adverse event profiles of total and high-dose LMW-ID and iron sucrose infusions in a heterogenous renal patient group comprising CKD, hemodialysis, and peritoneal dialysis. In this retrospective chart review study, we included 110 predialysis CKD, 101 peritoneal dialysis, and 118 hemodialysis patients. We included a total of 329 patients who were administered parenteral iron sucrose or LMW-ID between September 2006 and April 2010. Adverse events were determined both by medical and nursing follow-up notes. Laboratory data and clinical characteristics were collected from patient charts. Adverse event rates were compared between iron sucrose and LMW-ID infusions. In a total of 329 patients, 530 infusions (3470 ampules) were administered. We detected adverse reaction in only 1 patient. This adverse reaction, which manifested as generalized pruritus, occurred in a patient who received 500 mg of iron sucrose infusion. There were neither anaphylactic reactions nor deaths associated with infusion of either preparation. We did not observe any other adverse event related to administration of 500 and 1000 mg of iron sucrose at single infusion. The results of this study showed comparable safety of total dose LMW-ID and high-dose iron sucrose in a heterogenous group of renal patients.  相似文献   
266.
Clary sage seeds (Salvia sclarea L.) were obtained from plants cultivated, and 2.5, 4.0, 5.5, and 7.0 kGy doses of γ-irradiation were applied to the clary sage seeds. They were then analyzed for their protein, ash, oil and dry matter contents, and fatty acid composition. Additionally, the total phenolic contents, antiradical, antioxidant activities, and volatile compounds of the clary sage seed extract were determined. There was no significant difference in protein content. However, the moisture, oil, and ash contents of the samples were affected by irradiation. While the 7 kGy dose had a positive effect on the total phenolic content and antiradical activity of the sage seed extract, all doses have negative effects on the antioxidant activity of the sage seed. The main fatty acid of the sage seed was remarkably found as α-linolenic acid. The four irradiation levels caused significant differences in fatty acid composition by affecting all fatty acids except palmitic, palmitoleic, and eicosenoic acids. The dominant volatile compounds of control sage seed were found as β-pinene (18.81%) and limonene (15.60%). Higher doses of the irradiation decreased volatile components of sage seed. Clary sage seed including high omega-3 can be irradiated with low doses (≤ 2.5 kGy) of γ-irradiation. PRACTICAL APPLICATION: Clary sage is one of the most popular Salvia species in Turkey and many countries. Clary sage seed has approximately 29% oil content and this oil contains >50% of α-linolenic acid. γ-Irradiation is widely applied in the preservation of spice quality. The present study shows that the antioxidant activity of the clary sage seed is decreased by γ-irradiation. Additionally, higher doses of irradiation also decreased the volatile components of sage seed. Therefore, we suggest that clary sage seed which includes high levels of omega-3 should be irradiated with low doses (≤ 2.5 kGy) of γ-irradiation.  相似文献   
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