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OBJECTIVE: To determine the incidence and prognostic significance of documented eradication of breast cancer axillary lymph node (ALN) metastases after neoadjuvant chemotherapy. SUMMARY BACKGROUND DATA: Neoadjuvant chemotherapy is the standard of care for patients with locally advanced breast cancer and is being evaluated in patients with earlier-stage operable disease. METHODS: One hundred ninety-one patients with locally advanced breast cancer and cytologically documented ALN metastases were treated in two prospective trials of doxorubicin-based neoadjuvant chemotherapy. Patients had breast surgery with level I and II axillary dissection followed by additional chemotherapy and radiation treatment. Nodal sections from 43 patients who were originally identified as having negative ALNs at surgery were reevaluated and histologically confirmed to be without metastases. An additional 1112 sections from these lymph node blocks were obtained; half were stained with an anticytokeratin antibody cocktail and analyzed. Survival was calculated using the Kaplan-Meier method. RESULTS: Of 191 patients with positive ALNs at diagnosis, 23% (43 patients) were converted to a negative axillary nodal status on histologic examination (median number of nodes removed = 16). Of the 43 patients with complete axillary conversion, 26% (n = 11) had N1 disease and 74% (n = 32) had N2 disease. On univariate analysis, patients with complete versus incomplete histologic axillary conversion were more likely to have initial estrogen-receptor-negative tumors, smaller primary tumors, and a complete pathologic response in the primary tumor. The 5-year disease-free survival rates were 87% in patients with preoperative eradication of axillary metastases and 51% for patients with residual nodal disease after neoadjuvant chemotherapy. Of the 39 patients with complete histologic conversion for whom nodal blocks were available, occult nodal metastases were found in additional nodal sections in 4 patients (10%). At a median follow-up of 61 months, the 5-year disease-free survival rates were 87% in patients without occult nodal metastases and 75% in patients with occult nodal metastases. CONCLUSIONS: Neoadjuvant chemotherapy can completely clear the axilla of microscopic disease before surgery, and occult metastases are found in only 10% of patients with a histologically negative axilla. The results of this study have implications for the potential use of sentinel lymph node biopsy as an alternative to axillary dissection in patients treated with neoadjuvant chemotherapy.  相似文献   
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BACKGROUND: An imaging-guided unilateral surgical approach in patients with primary hyperparathyroidism (HPTH) requires reliable preoperative localization procedures. Using present imaging techniques, 60% to 80% of patients with primary HPTH can be treated successfully with limited surgery. Thus, further improvement of diagnostic accuracy is required. Computed axial tomography (CAT)-MIBI image fusion was introduced as a new technique for localizing enlarged parathyroid glands. We describe the new method and present its first results. METHODS: Six consecutive patients with primary HPTH underwent CAT-MIBI image fusion for preoperative parathyroid localization. CAT and technetium-99m-sestamibi scan were performed separately. The patient's head and neck were fixed with the noninvasive Vogele-Bale-Hohner Head Holder (VBH HeadFIX; Medical Intelligence, Schwabmünchen, Germany) and the BodyFIX (Medical Intelligence) vacuum cushion. Radiographic and scintigraphic markers were mounted at the head holder and the patient. CAT and MIBI images were fused by overlaying radiographic markers using a commercial software and workstation. RESULTS: In 5 patients, localization and dimension of the solitary adenomas were exactly predicted. In 1 patient with multiglandular disease (3 enlarged glands), CAT-MIBI image fusion was not able to predict multiple gland involvement. However, in a retrospective analysis of the localization study, the other two enlarged parathyroid glands could be correctly identified regarding their site and size. CONCLUSIONS: First results of CAT-MIBI image fusion are promising. The new technique provides a higher image resolution and better delimitation of enlarged parathyroid glands and adjacent anatomic structures than conventional scintigraphic methods.  相似文献   
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OBJECTIVES: Persisting air leakage after pulmonary resection remains a significant problem. The aim of the study was to evaluate the incidence of air leakage after standard lobectomy and test the efficacy and safety of TachoComb (TC). METHODS: A total of 189 patients undergoing lobectomy were enrolled in a multi-centre, open, randomised, and prospective study to test the efficacy and safety of TachoComb (TC) for air leakage treatment. Air leakage was assessed by water submersion test, and scored as grades 0 if no, 1 if countable, 2 if a stream of and 3 if coalescent bubbles have been observed. Any sites with grade 3 air leakage received further stapling or limited suturing until grade 0, 1 or 2 was obtained. Treatment of air leakage was done with TC or suturing according to randomisation. Air leakage was assessed by further submersion tests. Postoperative air leakage was assessed using the Pleur-Evac system. RESULTS: Overall incidence of air leakage 48+/-6 h after surgery was 34% for TC and 37% for standard treatment (P=0.76). The reduction of intra-operative air leak intensity in the subgroup with grades 1-2 was significantly higher for the TC group (P=0.015). Postoperative air leakage intensity in the subgroup with air leakage grades 1-2 was lower for TC than standard treatment (P=0.047). The mean duration of postoperative air leakage in the subgroup with grades 1-2 was shorter for the TC group than for standard treatment, i.e. 1.9+/-1.4 vs. 2.7+/-2.2 days (P=0.015). CONCLUSIONS: TC could be proven as well-tolerated and safe. In the subgroup of patients with established air leakage, TC showed superior potential in reduction of intra-operative air leakage as well as in reduction of intensity and duration of postoperative air leakage.  相似文献   
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Recurrent incisional hernia remains a major problem for the general surgeon. The high recurrence rate of incisional hernias after primary closure by tissue approximation led to the development of tension-free procedures using prosthetic materials. The goal of this study is to present the results of an extraperitoneal tension-free technique using a polyester mesh (Mersilene). A total of 43 patients with incisional hernias were surgically treated during a 9-year period in our department. Twenty-four patients (56%) had recurrent incisional hernias, 21 had primary repair by tissue approximation, and 3 had prolene mesh tension-free repair with wound infection. Patients' mean age was 68.2 years, and the mean postoperative follow-up was 54.4 months. Immediate postoperative complications were noticed in 9 patients (21%) subcutaneous seroma in 6 (14%) and wound infection in 3 (7%). Recurrence was noticed in 4 patients (9%) during the first 9 postoperative months. Late minor complications such as restriction of abdominal wall motility and chronic pain was noticed in 3 (7%) patients. In conclusion, the extraperitoneal onlay tension-free incisional hernia repair using polyester mesh is an easy and safe procedure with no major morbidity or recurrence rate.  相似文献   
87.
BackgroundDespite the effectiveness of Roux-en-Y gastric bypass (RYGB) in promoting excess weight loss, 40% of the patients regain weight. Endoscopic gastric plication (EGP) using the StomaphyX device can serve as a less-invasive procedure for promoting the loss of regained weight. Our objective was to evaluate the effectiveness of the StomaphyX device in sustaining ongoing weight loss in patients who have regained weight after RYGB at the Division of Minimally Invasive and Bariatric Surgery, Howard University Hospital.MethodsWe performed a retrospective chart review of patients undergoing EGP using the StomaphyX device from April 2008 to May 2010. The patient demographics and clinical information were assessed. Effective weight loss and the proportion of weight lost after EGP relative to the weight regained after achieving the lowest weight following RYGB was calculated.ResultsA total of 27 patients underwent EGP using the StomaphyX device; of these, most were women (n = 25, 93%) and black (n = 14, 52%), followed by white (n = 11, 42%), and Hispanic (n = 1, 4%). The median interval between RYGB and EGP was 6 years, with an interquartile range of 5–8 years. After the EGP procedure, the median effective weight loss was 37% (interquartile range 24–61%). Of the 27 patients, 18 had ≥6 months of follow-up after EGP. Eleven patients had achieved their lowest weight at 1–3 months, 7 at 6 months, and 3 at 12 months. Of the 18 patients, 13 (72%) experienced an increase in weight after achieving their lowest weight after EGP.ConclusionThe use of the StomaphyX device achieved the maximum effective weight loss during the 1–6-month period after EGP.  相似文献   
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New epigenetic technologies may uncover etiopathogenic mechanisms of major psychosis. In this study, we applied padlock probe-based ultra-deep bisulfite sequencing for fine mapping of modified cytosines of the HLA complex group 9 (nonprotein coding) gene in the postmortem brains of individuals affected with schizophrenia or bipolar disorder and unaffected controls. Significant differences between patients and controls were detected in both CpG and CpH modifications. In addition, we identified epigenetic age effects, DNA modification differences between sense and anti-sense strands, and demonstrated how DNA modification data can be used in clustering of patient populations. Our findings revealed new epigenetic complexities but also highlighted the potential of DNA modification approaches in the search of heterogeneous causes of major psychiatric disease.Key words: epigenetics, brain, schizophrenia, bipolar disorder, bisulfite sequencing, padlock probes  相似文献   
89.
An overall decline in the availability of osteogenic precursor cells and growth factors in the bone marrow microenvironment have been associated with impaired bone formation and osteopenia in humans. The objective of the current study was to determine if transplantation of mesenchymal stromal cells (MSC) from a healthy, young donor mouse into an osteopenic recipient mouse could enhance osseointegration of a femoral implant. MSC harvested from normal young adult mice differentiated into bone forming osteoblasts when cultured on implant grade titanium surfaces ex vivo and promoted bone formation around titanium-coated rods implanted in the femoral canal of osteopenic recipient mice. Micro computed tomographic imaging and histological analyses showed more, better quality, bone in the femur that received the MSC transplant compared with the contra-lateral control femur that received carrier alone. These results provide pre-clinical evidence that MSC transplantation promotes peri-implant bone regeneration and suggest the approach could be used in a clinical setting to enhance bone regeneration and healing in patients with poor quality bone.  相似文献   
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