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31.
The objective of this study was to maximize the success rate of sentinel node (SN) localization in breast cancer patients with the tracer that demonstrated the highest initial success during a preliminary evaluation. Altogether, 145 patients with operable invasive breast cancer and clinically negative lymph nodes were studied. Technetium 99m (99mTc)-sulfur colloid was injected into the breast parenchyma surrounding the invasive cancer or the biopsy cavity. Variable volumes of tracer, amounts of 99mTc, and duration of time between injection and surgery were evaluated. A hand-held gamma detector was used at surgery to locate and guide resection of all radioactive sentinel nodes (SNs), including those that were extraaxillary. A conventional lymphadenectomy was then performed in all cases. Based on previous studies, unfiltered sulfur colloid provided a higher success rate of SN identification than the other tracer types. Further evaluation with 99mTc-sulfur colloid demonstrated that increased volume increased the success rate of SN identification. An injection volume of 8 ml resulted in a success rate of 98%. SNs were not exclusively located in the axilla: In 8.6% of cases SNs were removed from an internal mammary location. The overall accuracy of patients with SNs resected was 98.4%, and the false-negative rate was 4.4%. It was concluded that (1) unfiltered 99mTc-sulfur colloid at a volume of 8 ml resulted in a high success rate for SN identification; (2) a significant number of the SNs were extraaxillary in location; and (3) the accuracy of the SNs for determining whether regional metastases had occurred was high. The U.S. National Cancer Institute is funding a randomized phase III clinical trial to evaluate SN resection compared to conventional axillary lymphadenectomy in clinical node-negative breast cancer patients. Major endpoints of this trial include long-term regional control and survival.  相似文献   
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-Tamoxifen reduces the incidence of breast cancer in women at risk for that disease. Because heart disease is the leading cause of death in women and because tamoxifen is also associated with venous thrombosis, an improved understanding of the association of tamoxifen with cardiovascular disease risk factors is required. In 111 healthy women at a single center, who were participating in a randomized double-blind breast cancer prevention trial, the 6-month effects of oral tamoxifen (20 mg/d) compared with placebo on factors related to inflammation, hemostasis, and lipids were studied. Tamoxifen was associated with reductions of 26% in median C-reactive protein, 22% in median fibrinogen, and 9% in cholesterol (all P:<0.01 compared with placebo). There were no differences in treatment effects on factor VII coagulant activity, fragment 1-2, and triglycerides. In secondary analyses, the effect of tamoxifen on C-reactive protein was larger in postmenopausal women and in women with higher waist-to-hip ratios. The effect on fibrinogen was larger in women with higher baseline cholesterol. Tamoxifen demonstrated effects on inflammatory markers that were consistent with reduced cardiovascular risk. These findings are in contrast to recent reports of increased C-reactive protein associated with postmenopausal estrogen. The potential for beneficial cardiovascular effects of tamoxifen in healthy women is suggested.  相似文献   
33.
Cancer occurrence after cosmetic breast implantation in Denmark   总被引:2,自引:0,他引:2  
Most studies on cancer incidence after breast implantation have focused on breast cancer, while the risk of cancers at other sites has been less well investigated. We examined cancer incidence among 1,653 women who underwent cosmetic breast implant surgery at private clinics of plastic surgery in Denmark and 1,736 women attending the same clinics for other reasons during the period 1973-1995. Furthermore, we updated previously reported results among 1,114 women who received implants for cosmetic indications at public hospitals. All women were followed for cancer through the Danish Cancer Registry. In comparison with the general female population, the overall standardized incidence ratio (SIR) for cancer among women who received implants in private clinics was 1.65 [95% confidence interval (CI) = 1.17-2.27]. This elevated SIR reflected increased incidence ratios for almost all major cancer sites; however, only for non-melanoma skin cancer was there an excess of more than 2 cases. No significant excess of cancer was observed among women who received implants in public hospitals (SIR = 1.10, 95% CI = 0.76-1.52) or among women attending the private clinics for other problems (SIR = 1.10, 95% CI = 0.78-1.52). The SIRs for breast cancer after breast implantation were 1.1 (95% CI = 0.5-2.2) among private clinic patients and 0.9 (95% CI = 0.4-1.7) among public hospital patients. The overall findings of these 2 implant cohorts and results from other investigations suggest that cancer risk is probably not increased among women receiving cosmetic breast implants. The inconsistent results for private clinics and public hospitals are likely related to selection bias and confounding among the private clinic patients, but our data did not permit exploration of these possibilities. Further research into the determinants of these inconsistencies is warranted.  相似文献   
34.
Background  Extra-axillary locations are known sites of lymph node metastases in patients with carcinoma of the breast. Methods  A technique utilizing a gamma probe was used to identify hot spots representing sentinel nodes residing in either axillary or extra-axillary locations in 680 patients with operable, clinically node-negative breast cancer. All identified sentinel nodes were excised. Results  Results showed that extra-axillary hot spots were found in 6.5% of patients. This rate increased to 14.8% if patients were injected with 8.0 ml unfiltered Technetium-99m-Sulfur colloid. Extra-axillary metastatic disease was identified in 6.8% of patients with extra-axillary hot spots. In patients with extra-axillary drainage, pathologically-positive nodes were exclusive to extra-axillary sites (ie, no axillary metastases) in 4.5% of cases. Factors found to increase the likelihood of identifying extra-axillary hot spots included; an increased volume of injection, medial or central tumor locations and T3 primary tumors. Conclusion  Gamma probe-guided techniques can identify extra-axillary sentinel nodes, which are at risk for harboring metastatic disease. Removal of these nodes can be done with little morbidity and may improve staging in the individual patient.  相似文献   
35.
Presurgical colorectal cancer patients (n = 116) received single intravenous infusions of 1 mg of CYT-103 (OncoScint CR103), an immunoconjugate of monoclonal antibody B72.3, radiolabeled with 111In. Following gamma camera imaging, 103 patients underwent an operative procedure: 92 had primary or recurrent colorectal carcinoma, 1 patient evaluated for recurrence of colorectal cancer had a second primary malignancy (small cell lung), and 10 patients had no demonstrable evidence of malignancy. 111In-CYT-103 immunoscintigraphic findings were consistent with the pathologic diagnoses for 70% of patients with colorectal cancer and 90% of disease-free patients. Antibody imaging contributed to surgical decision making through the detection of occult disease (12% of patients) and the confirmation of localized, potentially resectable disease without regional or metastatic spread. Seven patients (6%) experienced adverse effects, primarily fevers and itching, and 33% of patients developed antibodies to murine immunoglobulin after administration of 111In-CYT-103. The results of this study suggest that 111In-CYT-103 is a useful diagnostic tool for the presurgical evaluation of colorectal cancer patients.  相似文献   
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In each of eight thoracolumbar human cadaveric vertebrae, a hole was made through one pedicle into the vertebral body with a drill bit and through the contralateral pedicle with a probe. Identical metal screws were implanted into the holes to equal depths, and maximum pull-out force was determined for each screw. Using a paired Student t test, no significant difference (P = 0.87) was found in pull-out strength between the screws implanted into drilled holes and those implanted into probed holes. In fact, the average pull-out strengths for the two groups differed by less than 2%. The pedicular cortex was broken through during hole preparation in 5 of the 16 pedicles: 3 as a result of drilling and 2 secondary to probing. The average pull-out strength of the screws in these five pedicles was 11.0% less than the average pull-out strength of the screws implanted into the contralateral intact pedicles. Although this does not represent a statistically significant difference (P = 0.15), it suggests that damaging the pedicular cortex may weaken pedicle screw fixation.  相似文献   
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After extensive resection due to extremity sarcoma, the inability to cover the defect for satisfactory healing and limb function has been an indication for amputation rather than limb salvage. We report herein our experience with seven limb-salvage cases in which we closed difficult and complex defects with composite tissue transfers utilizing microvascular techniques. Free-flap transfers were used to cover soft-tissue defects after extensive resection of primary and locally recurrent tumor and to manage radiation-induced complications. The grafts healed well when infected irradiated tissue was covered, and the grafts tolerated postoperative irradiation. Composite tissue transfer also provided soft-tissue coverage around distal joints that would not have been adequately protected with a skin graft. Complications were minimal, and all patients maintained good extremity function. No patient who underwent composite tissue transfer has had a local recurrence. A free-flap composite tissue transfer can extend the indications for limb-salvage surgery and offers an alternative to amputation in selected patients.  相似文献   
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