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81.
In lymph-node-negative invasive breast cancer patients<55 years, the proliferation marker mitotic activity index (MAI) has previously been shown to be the strongest prognosticator. In studies without age definition, MAI was not strongly prognostic. We investigated the age dependency of the prognostic value of proliferation for distant metastasis-free (MFS) and overall cancer-related survival (OS) in 1004 histologically diagnosed T1-3N0M0 invasive breast cancers (n=516, <55 years; n=322, 55-70 years; n=166, >70 years) without systemic adjuvant therapy and long follow-up (median: 108 months). The MAI decreases with age and the prognostic value of MAI varied by age group. For patients<55 years, hazard ratios (HR) for MAI>or=10 versus<10 for MFS and OS were 3.1 and 4.4, respectively (P<.0001 for both), but only 1.9 and 1.9 (P=.004 and .006) for patients aged 55-70 years, while over 70 years, MAI was not significant (P=.11). The prognostic value of proliferation was age-dependent. Prognostic breast cancer studies must clearly indicate the age group being studied.  相似文献   
82.
AIMS: To investigate the population pharmacokinetics and pharmacodynamics of doxorubicin and cyclophosphamide in breast cancer patients. PATIENTS AND METHODS: Sixty-five female patients with early or advanced breast cancer received doxorubicin 60 mg/m(2) over 15 minutes followed by cyclophosphamide 600 mg/m(2) over 15 minutes. The plasma concentration-time data of both drugs were measured, and the relationship between drug pharmacokinetics and neutrophil counts was evaluated using nonlinear mixed-effect modelling. Relationships were explored between drug exposure (the area under the plasma concentration-time curve [AUC]), toxicity and tumour response. RESULTS: Fifty-nine patients had complete pharmacokinetic and toxicity data. In 50 patients with measurable disease, the objective response rate was 60%, with complete responses in 6% of patients. Both doxorubicin and cyclophosphamide pharmacokinetics were associated with neutrophil toxicity. Cyclophosphamide exposure (the AUC) was significantly higher in patients with at least stable disease (n = 44) than in patients with progressive disease (n = 6; 945 micromol . h/L [95% CI 889, 1001] vs 602 micromol . h/L [95% CI 379, 825], p = 0.0002). No such correlation was found for doxorubicin. Body surface area was positively correlated with doxorubicin clearance; AST and patient age were negatively correlated with doxorubicin clearance; creatinine clearance was positively correlated with doxorubicinol clearance; and occasional concurrent use of carbamazepine was positively correlated with cyclophosphamide clearance. CONCLUSIONS: The proposed inhibitory population pharmacokinetic-pharmacodynamic model adequately described individual neutrophil counts after administration of doxorubicin and cyclophosphamide. In this patient population, exposure to cyclophosphamide, as assessed by the AUC, might have been a predictor of the treatment response, whereas exposure to doxorubicin was not. A prospective study should validate cyclophosphamide exposure as a predictive marker for the treatment response and clinical outcome in this patient group.  相似文献   
83.
The Van Nuys Prognostic Index 1996 (VNPI), based upon tumor size, pathological grade and tumor margins, is a guideline for the treatment of ductal carcinoma in situ (DCIS). It was thought to strongly decrease overtreatment. In 2003, age was added to the index as a fourth prognostic factor. We examined changes in treatment modality after applying the VNPI retrospectively and investigated if the addition of age to the Index causes a shift in treatment. The influence of each prognostic factor on disease-free survival (DFS) was calculated. We performed a retrospective file study of DCIS patients treated between 1985 and 2003 at the University Hospital, Antwerp. Patients were assigned a Van Nuys Score 1996 and 2003. The influence of tumor size, pathological grade, tumor margins and age on DFS was calculated with the Kaplan-Meier method and the log-rank test. We identified 104 DCIS cases with a median follow-up of 36 months. Twelve patients showed recurrence (11.5%), of whom seven were invasive (58%). Seventeen of the 29 women diagnosed before 1997 were undertreated according to the VNPI 1996 and six of them showed recurrence. The remaining three recurrences were correctly treated. Seventy-five patients diagnosed after 1997 were all treated according to the VNPI 1996 and only three had a recurrence. The introduction of age caused no significant shift in treatment modalities. Significant differences in DFS were seen between large (>41 mm) and small (<15 mm) tumors (p = 0.0074), old (>60 years) and young (<40 years) patients (p = 0.024) and Van Nuys Subgroup 2 and 3 (p = 0.04). Tumor margins and pathological grade showed no significant difference in DFS. The VNPI can be a useful tool in the treatment of DCIS. However, this Index is not evidence-based, using a relatively small retrospective series of patients. The validity of the modified VNPI must be prospectively confirmed with large numbers of DCIS patients.  相似文献   
84.
BACKGROUND: Isolated lung perfusion (ILuP) with melphalan was performed under normo- and hyperthermic conditions combined with pulmonary metastasectomy for patients with resectable lung metastases. We present the results of pharmacokinetic analysis of a phase I and extension trial. METHODS: Twenty-one procedures of ILuP with melphalan were performed in the phase I trial according to a dose-escalation schedule under normothermic and hyperthermic conditions followed by surgical resection of pulmonary metastases. In an extension trial 8 additional procedures with 15 and 45 mg melphalan were performed under hyperthermic conditions. Samples of serum, perfusate, lung, and tumor tissue were obtained. RESULTS: High perfusate concentrations of melphalan were recorded in contrast to low systemic concentrations. Marked interindividual variability was observed in melphalan concentrations in perfusate, tumor, and lung tissue. Statistically significant correlation between melphalan dose, and perfusate area under the concentration-time curve (R(2) = 0.578, P = 0.001) and lung tissue concentrations (R(2) = 0.459, P = 0.028) were noted. No significant correlation between melphalan dose and tumor tissue concentrations could be established. CONCLUSION: Isolated lung perfusion effectively delivers high doses of melphalan to the lung and tumor tissues with minimal systemic levels. Significant correlation between perfused melphalan dose, perfusate area under the concentration-time curve and lung tissue melphalan concentrations were observed.  相似文献   
85.
86.
We have studied serum immunoreactive erythropoietin (SIE) levels in 28 patients with sickle cell anemia (SCA) without renal insufficiency and in 17 patients with nonhemoglobinopathy anemias of comparable severity using a sensitive radioimmunoassay procedure. An exponential relationship between SIE level and degree of anemia was noted in all patients. However, in nonhemoglobinopathy anemia, a sharp rise in the SIE level occurred as hemoglobin (Hb) levels fell below about 12 g/dL, whereas in sickle cell patients the increase was not marked until hemoglobin fell to about 9 g/dL. The response was more blunted in older SCA patients than in younger ones. A linear regression model relating SIE level to Hb level, presence/absence of SCA, and age explained 63% of the variation in SIE. We conclude that the serum erythropoietin levels in SCA increased at a lower hemoglobin concentration and are of a lower magnitude than that of the other anemias.  相似文献   
87.
88.
89.
Serum CA 125 regression after cytoreductive surgery and during the first three courses of chemotherapy was studied in 60 ovarian cancer patients and compared to known prognostic factors. Various methods reported in the literature to calculate a CA 125 half-live value were compared. Using two exponential regression models (Van der Burg et al., 1988; Buller et al., 1991), mean half-lives in stage I-II patients after complete cytoreductive surgery were respectively 10.7 days (range: 5-23) and 9.8 days (range: 7-15). Within stage III-IV patients, a significant positive correlation was seen between survival and (a) stage III (P = 0.002), (b) residual tumour < or = 1 cm (P = 0.02), (c) CA 125 normalisation after three courses (P = 0.003) and (d) CA 125 half-life < or = 20 days (P = 0.02-0.004, depending on the method used for half-life calculation). The median survival times of patients with and without a CA 125 normalisation after three courses were 27 and 14 months respectively (P = 0.003). When using the model of Buller et al. patients with a CA 125 half-life < or = 20 days had a median survival of 28 months compared to a median survival of 19 months for patients with CA 125 half-lives > 20 days (P = 0.004). Half-life calculations only showed a significant correlation with survival, if pre-surgery CA 125 levels were used as a baseline. In a survival analysis using the Cox proportional hazards model, stage of disease was the most predictive variable for survival (P = 0.006). The only additional independent prognostic factor for survival was the CA 125 half-life calculated according to Buller [derived from the formula: CA 125 = exp. [i-s x (days after surgery)], in which i is the y-axis intercept and s is the slope of the CA 125 regression curve]. A CA 125 half-life < or = 20 days vs > 20 days calculated using this formula, provides an independent prognostic factor for survival in stage III-IV patients early in the course of therapy (P = 0.04).  相似文献   
90.
JB Epstein 《Oral diseases》1997,3(Z1):S124-S128
Kaposi's sarcoma (KS) is the most common neoplastic disease in patients with disease due to human immunodeficiency virus (HIV), and oral KS (OKS) is the commonest oral neoplasia. OKS has been managed by local excision, intralesional chemotherapy regional radiotherapy, and systemic chemotherapy. Comparison between studies is difficult as the severity of oral involvement is not well defined in most studies. This paper reviews the approach to the management of OKS and also presents a proposal for the clinical staging of OKS. Clinical staging of OKS will facilitate comparisons of outcomes of treatment of OKS and improve our understanding of the natural history of the neoplasia, which has varied presentation and rates of progression.  相似文献   
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