Anterior approaches to the spine for the treatment of spinal tumors have gained acceptance; howev... more Anterior approaches to the spine for the treatment of spinal tumors have gained acceptance; however, in most published reports, patients with primary, metastatic, or chest wall tumors involving cervical, thoracic, or lumbar regions of the spine are combined. The purpose of this study was to provide a clear perspective of results that can be expected in patients who undergo anterior vertebral body resection, reconstruction, and stabilization for spinal metastases that are limited to the thoracic region. Outcome is presented for 72 patients with metastatic spinal tumors who were treated by transthoracic vertebrectomy at The University of Texas M. D. Anderson Cancer Center. The predominant primary tumors included renal cancer in 19 patients, breast cancer in 10, melanoma or sarcoma in 10, and lung cancer in nine patients. The most common presenting symptoms were back pain, which occurred in 90% of patients, and lower-extremity weakness, which occurred in 64% of patients. All patients underwent transthoracic vertebrectomy, decompression, reconstruction with methylmethacrylate, and anterior fixation with locking plate and screw constructs. Supplemental posterior instrumentation was required in seven patients with disease involving the cervicothoracic or thoracolumbar junction, which was causing severe kyphosis. After surgery, pain improved in 60 of 65 patients. This improvement was found to be statistically significant (p < 0.001) based on visual analog scales and narcotic analgesic medication use. Thirty-five of the 46 patients who presented with neurological dysfunction improved significantly (p < 0.001) following the procedure. Thirty-three patients had weakness but could ambulate preoperatively. Seventeen of these 33 regained normal strength, 15 patients continued to have weakness, and one patient was neurologically worse postoperatively. Of the 13 preoperatively nonambulatory patients, 10 could walk after surgery and three were still unable to walk but showed improved motor function. Twenty-one patients had complications ranging from minor atelectasis to pulmonary embolism. The 30-day mortality rate was 3%. The 1-year survival rate for the entire study population was 62%. These results suggest that transthoracic vertebrectomy and spinal stabilization can improve the quality of life considerably in cancer patients with spinal metastasis by restoring or preserving ambulation and by controlling intractable spinal pain with acceptable rates of morbidity and mortality.
The extent of tumor resection that should be undertaken in patients with glioblastoma multiforme ... more The extent of tumor resection that should be undertaken in patients with glioblastoma multiforme (GBM) remains controversial. The purpose of this study was to identify significant independent predictors of survival in these patients and to determine whether the extent of resection was associated with increased survival time. The authors retrospectively analyzed 416 consecutive patients with histologically proven GBM who underwent tumor resection at the authors' institution between June 1993 and June 1999. Volumetric data and other tumor characteristics identified on magnetic resonance (MR) imaging were collected prospectively. Five independent predictors of survival were identified: age, Karnofsky Performance Scale (KPS) score, extent of resection, and the degree of necrosis and enhancement on preoperative MR imaging studies. A significant survival advantage was associated with resection of 98% or more of the tumor volume (median survival 13 months, 95% confidence interval [CI] 11.4-14.6 months), compared with 8.8 months (95% CI 7.4-10.2 months; p < 0.0001) for resections of less than 98%. Using an outcome scale ranging from 0 to 5 based on age, KPS score, and tumor necrosis on MR imaging, we observed significantly longer survival in patients with lower scores (1-3) who underwent aggressive resections, and a trend toward slightly longer survival was found in patients with higher scores (4-5). Gross-total tumor resection is associated with longer survival in patients with GBM, especially when other predictive variables are favorable.
The expression of activation antigens, namely CD25, CD69, CD71, and HLA-DR on T cells from 15 hea... more The expression of activation antigens, namely CD25, CD69, CD71, and HLA-DR on T cells from 15 healthy individuals stimulated with different mitogens and specific antigens was evaluated by immunofluorescence assay and flow cytometric analysis and compared with cell proliferation as a function of [3H]thymidine incorporation. CD69 was the earliest expressed antigen on stimulated cells, while HLA-DR was the latest. Regardless of the stimulus used, lymphocytes expressing CD25 and CD71 were always more numerous than cells expressing CD69 and HLA-DR. Variations in the proportion of CD4+ and CD8+ T cells expressing each activation marker were observed with different antigenic stimuli. The expression of each activation marker showed overall agreement with the [3H]thymidine incorporation assay in discriminating between positive and negative immune response. However, no correlation was observed between the percentage of CD25-, CD69-, CD71-, and HLA-DR-positive T cells and the amount of [3H]thymidine incorporation. Moreover, low doses of mitogens and antigens as well as short time of stimulation were sufficient to induce T cells to express activation antigens but not to proliferate. Our data show that results obtained by flow cytometry and [3H]thymidine incorporation may differ qualitatively, at least under certain conditions; this suggests that the 2 assays are complementary, and when combined, may gives a clearer understanding of events leading to efficient cell-mediated immune response.
To compare the efficacy and toxicity of fluconazole and amphotericin B in the treatment of hemato... more To compare the efficacy and toxicity of fluconazole and amphotericin B in the treatment of hematogenous candidiasis in cancer patients.A matched cohort study of cancer patients with hematogenous candidiasis was conducted. Forty-five patients with hematogenous candidiasis who received fluconazole (200 to 600 mg/day) in an open-label trial at the University of Texas M. D. Anderson Cancer Center, Houston, Texas, between February 1990 and June 1992 were matched to 45 patients treated with amphotericin B (0.3 to 1.2 mg/kg/day) for the same diagnosis. Criteria for matching included the following prognostic variables at the initiation of therapy: pneumonia, neutropenia (<1,000 cells/mm3), number of positive blood cultures before therapy, infecting Candida species, underlying disease, and the simplified acute physiology score. Response and survival at 48 hours, after 5 days of therapy, and at the end of therapy, as well as toxicity rates were obtained. Other post hoc analyses were performed. Differences in outcomes were assessed by the McNemar, the sign, and the log rank tests.Patients were similar with respect to the matching criteria, age, sex, status of underlying disease, use of antibiotics and growth factors, duration of treatment, presence and removal of central venous catheters, disseminated disease, and concomitant infections. Response rates at 48 hours and 5 days were similar between the two study groups. Overall response rates at the end of therapy were 73% for patients treated with fluconazole and 71% for patients treated with amphotericin B (P = 0.78.). There were no differences in survival rates or causes of death. Toxicity was observed in 9% of patients treated with fluconazole and in 67% of patients treated with amphotericin B (P <0.0001). Toxic effects of amphotericin B included nephrotoxicity, hypokaliemia, and fever and chills.Fluconazole is effective and better tolerated than amphotericin B for the treatment of hematogenous candidiasis in cancer patients.
Anterior approaches to the spine for the treatment of spinal tumors have gained acceptance; howev... more Anterior approaches to the spine for the treatment of spinal tumors have gained acceptance; however, in most published reports, patients with primary, metastatic, or chest wall tumors involving cervical, thoracic, or lumbar regions of the spine are combined. The purpose of this study was to provide a clear perspective of results that can be expected in patients who undergo anterior vertebral body resection, reconstruction, and stabilization for spinal metastases that are limited to the thoracic region. Outcome is presented for 72 patients with metastatic spinal tumors who were treated by transthoracic vertebrectomy at The University of Texas M. D. Anderson Cancer Center. The predominant primary tumors included renal cancer in 19 patients, breast cancer in 10, melanoma or sarcoma in 10, and lung cancer in nine patients. The most common presenting symptoms were back pain, which occurred in 90% of patients, and lower-extremity weakness, which occurred in 64% of patients. All patients underwent transthoracic vertebrectomy, decompression, reconstruction with methylmethacrylate, and anterior fixation with locking plate and screw constructs. Supplemental posterior instrumentation was required in seven patients with disease involving the cervicothoracic or thoracolumbar junction, which was causing severe kyphosis. After surgery, pain improved in 60 of 65 patients. This improvement was found to be statistically significant (p &amp;amp;lt; 0.001) based on visual analog scales and narcotic analgesic medication use. Thirty-five of the 46 patients who presented with neurological dysfunction improved significantly (p &amp;amp;lt; 0.001) following the procedure. Thirty-three patients had weakness but could ambulate preoperatively. Seventeen of these 33 regained normal strength, 15 patients continued to have weakness, and one patient was neurologically worse postoperatively. Of the 13 preoperatively nonambulatory patients, 10 could walk after surgery and three were still unable to walk but showed improved motor function. Twenty-one patients had complications ranging from minor atelectasis to pulmonary embolism. The 30-day mortality rate was 3%. The 1-year survival rate for the entire study population was 62%. These results suggest that transthoracic vertebrectomy and spinal stabilization can improve the quality of life considerably in cancer patients with spinal metastasis by restoring or preserving ambulation and by controlling intractable spinal pain with acceptable rates of morbidity and mortality.
The extent of tumor resection that should be undertaken in patients with glioblastoma multiforme ... more The extent of tumor resection that should be undertaken in patients with glioblastoma multiforme (GBM) remains controversial. The purpose of this study was to identify significant independent predictors of survival in these patients and to determine whether the extent of resection was associated with increased survival time. The authors retrospectively analyzed 416 consecutive patients with histologically proven GBM who underwent tumor resection at the authors&amp;amp;amp;amp;#39; institution between June 1993 and June 1999. Volumetric data and other tumor characteristics identified on magnetic resonance (MR) imaging were collected prospectively. Five independent predictors of survival were identified: age, Karnofsky Performance Scale (KPS) score, extent of resection, and the degree of necrosis and enhancement on preoperative MR imaging studies. A significant survival advantage was associated with resection of 98% or more of the tumor volume (median survival 13 months, 95% confidence interval [CI] 11.4-14.6 months), compared with 8.8 months (95% CI 7.4-10.2 months; p &amp;amp;amp;amp;lt; 0.0001) for resections of less than 98%. Using an outcome scale ranging from 0 to 5 based on age, KPS score, and tumor necrosis on MR imaging, we observed significantly longer survival in patients with lower scores (1-3) who underwent aggressive resections, and a trend toward slightly longer survival was found in patients with higher scores (4-5). Gross-total tumor resection is associated with longer survival in patients with GBM, especially when other predictive variables are favorable.
The expression of activation antigens, namely CD25, CD69, CD71, and HLA-DR on T cells from 15 hea... more The expression of activation antigens, namely CD25, CD69, CD71, and HLA-DR on T cells from 15 healthy individuals stimulated with different mitogens and specific antigens was evaluated by immunofluorescence assay and flow cytometric analysis and compared with cell proliferation as a function of [3H]thymidine incorporation. CD69 was the earliest expressed antigen on stimulated cells, while HLA-DR was the latest. Regardless of the stimulus used, lymphocytes expressing CD25 and CD71 were always more numerous than cells expressing CD69 and HLA-DR. Variations in the proportion of CD4+ and CD8+ T cells expressing each activation marker were observed with different antigenic stimuli. The expression of each activation marker showed overall agreement with the [3H]thymidine incorporation assay in discriminating between positive and negative immune response. However, no correlation was observed between the percentage of CD25-, CD69-, CD71-, and HLA-DR-positive T cells and the amount of [3H]thymidine incorporation. Moreover, low doses of mitogens and antigens as well as short time of stimulation were sufficient to induce T cells to express activation antigens but not to proliferate. Our data show that results obtained by flow cytometry and [3H]thymidine incorporation may differ qualitatively, at least under certain conditions; this suggests that the 2 assays are complementary, and when combined, may gives a clearer understanding of events leading to efficient cell-mediated immune response.
To compare the efficacy and toxicity of fluconazole and amphotericin B in the treatment of hemato... more To compare the efficacy and toxicity of fluconazole and amphotericin B in the treatment of hematogenous candidiasis in cancer patients.A matched cohort study of cancer patients with hematogenous candidiasis was conducted. Forty-five patients with hematogenous candidiasis who received fluconazole (200 to 600 mg/day) in an open-label trial at the University of Texas M. D. Anderson Cancer Center, Houston, Texas, between February 1990 and June 1992 were matched to 45 patients treated with amphotericin B (0.3 to 1.2 mg/kg/day) for the same diagnosis. Criteria for matching included the following prognostic variables at the initiation of therapy: pneumonia, neutropenia (<1,000 cells/mm3), number of positive blood cultures before therapy, infecting Candida species, underlying disease, and the simplified acute physiology score. Response and survival at 48 hours, after 5 days of therapy, and at the end of therapy, as well as toxicity rates were obtained. Other post hoc analyses were performed. Differences in outcomes were assessed by the McNemar, the sign, and the log rank tests.Patients were similar with respect to the matching criteria, age, sex, status of underlying disease, use of antibiotics and growth factors, duration of treatment, presence and removal of central venous catheters, disseminated disease, and concomitant infections. Response rates at 48 hours and 5 days were similar between the two study groups. Overall response rates at the end of therapy were 73% for patients treated with fluconazole and 71% for patients treated with amphotericin B (P = 0.78.). There were no differences in survival rates or causes of death. Toxicity was observed in 9% of patients treated with fluconazole and in 67% of patients treated with amphotericin B (P <0.0001). Toxic effects of amphotericin B included nephrotoxicity, hypokaliemia, and fever and chills.Fluconazole is effective and better tolerated than amphotericin B for the treatment of hematogenous candidiasis in cancer patients.
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