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141.
The feasibility and diagnostic reliability of sentinel node (SN) biopsy for gastric cancer are still controversial. We studied the clinicopathological features and localization of solitary lymph node metastasis (SLM) in gastric cancer to provide useful information for use of the SN concept in gastric cancer. From 2000 to 2004, 3,267 patients with gastric cancer underwent D2 radical gastrectomy. The clinicopathological features of 195 patients with histologically proven SLM and the distribution of metastasized nodes were assessed. The incidence of SLM was 6.0% in all cases. Compared with the node-negative patients, significant differences were observed in age, tumor size, depth of invasion, and surgical type. The cumulative 5-year survival rate of patients with SLM was 80.5%, which was significantly lower than 90.2% for node-negative patients (P < 0.001). Of patients with SLM, 82.6% had it in the perigastric node area (N1), and the other 17.4% patients had skip metastasis in the N2-N3 nodes. Perigastric nodes were the most common first sites of drainage from the tumor, making them the main targets of the operative SN mapping procedure. Due to the higher than expected incidence of skip metastasis in gastric cancer, D2 lymphadenectomy should be performed until the reliability of SN navigation surgery is validated in multicenter prospective clinical trials.  相似文献   
142.
Background and objectives In breast cancer, the expression pattern of CXCR4 may be correlated with the degree of axillary lymph node involvement. The aim of this study was to evaluate the contributing factors that contribute to the correlation between CXCR4 expression and axillary lymph node metastasis in breast cancer. Methods Between August 1997 and August 2002, sections of paraffin-embedded tissue were obtained from 107 patients who received optimal treatment for breast cancer. The expression of CXCR4 was evaluated by immunohistochemical staining. Results A significant correlation was found in the expression of nuclear CXCR4 and lymph node metastasis (P = 0.03). We found a significant correlation between a high nuclear expression of CXCR4 and axillary lymphatic metastasis in estrogen and progesterone receptor negative breast cancer (P = 0.01 and P = 0.01). There was a significant correlation between the high expression of nuclear CXCR4 and axillary lymphatic metastasis in comparisons between positive estrogen and/or progesterone receptor expression and negative expression (P = 0.02). Conclusions Our results showed that high expression of nuclear CXCR4 was significantly correlated with lymph node metastasis in breast cancer. The high expression of nuclear CXCR4 in hormone receptor negative breast cancer was associated with a high possibility of lymph node metastasis.  相似文献   
143.
Background The objectives of this study were to investigate the clinicopathological features of branch intraductal papillary mucinous neoplasm (IPMN) and to determine safe criteria for its observation. Most clinicians agree that surgical resection is required to treat main duct-type IPMN because of its high malignancy rate. However, no definite treatment guideline (with respect to surgery or observation) has been issued on the management of branch duct type IPMN. Methods We retrospectively reviewed the clinicopathological data of 138 patients who underwent operations for IPMN between 1993 and 2006 at five institutes in Korea. Results Of 138 patients (mean age, 60.6 years; 87 men, 51 women), 76 underwent pancreatoduodenectomy, 39 distal pancreatectomy, 4 total pancreatectomy, and 20 limited pancreatic resection. There were 112 benign cases: 47 adenoma, 63 borderline cases, and 26 malignant cases, with 9 of these being noninvasive and 17 invasive. By univariate analysis, tumor size and the presence of a mural nodule were identified as meaningful predictors of malignancy. By receiver operating characteristic curve analysis, a tumor size of >2 cm was found to be the most valuable predictor of malignancy. When cases were classified according to tumor size and the presence of a mural nodule, the malignancy rate for a tumor ≤2 cm without a mural nodule was 9.2%, for a tumor of ≤2 cm plus a mural nodule was 25%, and for other conditions such as tumor >2 cm, >25%. Conclusions Many branch duct IPMNs are malignant. Surgical treatment is recommended, except in cases that are strongly suspected to be benign or cases that present a high operative risk. Observation is only recommended in patients with a tumor size of ≤2 cm without a mural nodule.  相似文献   
144.
Schwannomas are particularly rare neoplasms among tumors of the retroperitoneal space. Only 0.3-3.2% of benign schwannomas are found in retroperitoneal locations. As these tumors are usually asymptomatic and discovered by chance or in the course of the evaluation of an unrelated health problem, they may cause the delay of early diagnosis and treatment. With recent advances in the field of minimally invasive surgery, several laparoscopic approaches to retroperitoneal schwannomas have been reported. In this paper, we present the case of a 59-year-old female patient with an asymptomatic retroperitoneal mass that was found during a regular medical checkup. The mass was located between the inferior vena cava (IVC) and aorta under the pancreaticoduodenal unit (site of lymph node 16b1), compressing the IVC. She underwent successful laparoscopic surgery for retroperitoneal schwannoma. In addition, we summarized the literature on cases regarding the laparoscopic management of the retroperitoneal schwannoma.  相似文献   
145.
OBJECT: Approximately 20% of patients with an intracranial saccular aneurysm report a family history of intracranial aneurysm (IA) or subarachnoid hemorrhage. A better understanding of predictors of aneurysm detection in familial IA may allow more targeted aneurysm screening strategies. METHODS: The Familial Intracranial Aneurysm (FIA) study is a multicenter study, in which the primary objective is to define the susceptibility genes related to the formation of IA. First-degree relatives (FDRs) of those affected with IA are offered screening with magnetic resonance (MR) angiography if they were previously unaffected, are > or = 30 years of age, and have a history of smoking and/or hypertension. Independent predictors of aneurysm detection on MR angiography were determined using the generalized estimating equation version of logistic regression. RESULTS: Among the first 303 patients screened with MR angiography, 58 (19.1%) had at least 1 IA, including 24% of women and 11.7% of men. Ten (17.2%) of 58 affected patients had multiple aneurysms. Independent predictors of aneurysm detection included female sex (odds ratio [OR] 2.46, p = 0.001), pack-years of cigarette smoking (OR 3.24 for 20 pack-years of cigarette smoking compared with never having smoked, p < 0.001), and duration of hypertension (OR 1.26 comparing those with 10 years of hypertension to those with no hypertension, p = 0.006). CONCLUSIONS: In the FIA study, among the affected patients' FDRs who are > 30 years of age, those who are women or who have a history of smoking or hypertension are at increased risk of suffering an IA and should be strongly considered for screening.  相似文献   
146.
BACKGROUND: The integration of tendon grafts used for replacement of the anterior cruciate ligament is still sometimes unsatisfactory and may be associated with postoperative anterior-posterior laxity. The goal of this study was to examine the capacity of bone morphogenetic protein-2 (BMP-2) gene transfer to improve the integration of semitendinosus tendon grafts at the tendon-bone interface after reconstruction of the anterior cruciate ligament in rabbits. METHODS: The anterior cruciate ligaments of adult New Zealand White rabbits were replaced with autologous double-bundle semitendinosus tendon grafts. The semitendinosus tendon grafts had been infected in vitro with adenovirus-luciferase, adenovirus-LacZ (AdLacZ), or adenovirus-BMP-2 (AdBMP-2); untreated grafts served as controls. The grafts were examined histologically at two, four, six, and eight weeks after surgery. In additional experiments, the structural properties of the femur-anterior cruciate ligament graft-tibia complexes, from animals killed eight weeks postoperatively, were determined from uniaxial tests. The stiffness (N/mm) and ultimate load to failure (N) were determined from the resulting load-elongation curves. RESULTS: Genetically engineered semitendinosus tendon grafts expressed reporter genes as well as BMP-2 in vitro. The AdLacZ-infected grafts showed two different histological patterns of transduction. Intra-articularly, infected cells were mostly aligned along the surface, and they decreased in number between two and eight weeks after surgery. In the intra-tunnel portions of the grafts, the number of infected cells did not decrease during the observation period. Moreover, a high number of transduced cells was found in the deeper layers of the tendons. In the control group, granulation-type tissue at the tendon-bone interface showed progressive reorganization into a dense connective tissue, and a later establishment of fibers resembling Sharpey fibers. In the specimens with an AdBMP-2-infected anterior cruciate ligament graft, a broad zone of newly formed matrix resembling chondro-osteoid had formed at the tendon-bone interface at four weeks after surgery. This area was increased at six weeks, showing a transition from bone to mineralized cartilage and nonmineralized fibrocartilage. In addition, in the AdBMP-2-treated specimens, the tendon-bone interface in the osseous tunnel was similar to that of a normal anterior cruciate ligament insertion. The stiffness (29.0 +/- 7.1 N/mm compared with 16.7 +/- 8.3 N/mm) and the ultimate load to failure (108.8 +/- 50.8 N compared with 45.0 +/- 18.0 N) were significantly enhanced in the specimens with an AdBMP-2-transduced graft when compared with the control values (p < 0.05). CONCLUSION: This study demonstrates that BMP-2 gene transfer significantly improves the integration of semitendinosus tendon grafts in bone tunnels after reconstruction of the anterior cruciate ligament in rabbits. Clinical Relevance: Novel technologies including gene therapy and tissue engineering, such as those described in this study, may provide useful therapeutic procedures to enhance biological healing after reconstruction of the anterior cruciate ligament.  相似文献   
147.
Gender differences in patellofemoral joint biomechanics   总被引:10,自引:0,他引:10  
Patellofemoral pain is associated with patellar malalignment and quadriceps weakness which are seen more commonly in women. The objective of the current study was to determine the effects of gender, vastus medialis strength, and tibial rotation on patellofemoral joint biomechanics. Twelve fresh-frozen knees from cadavers were tested using a custom knee jig. Anatomic multiplane loading of the extensor mechanism was used with varying vastus medialis loads. Patellofemoral contact area and pressure were measured using pressure sensitive film at knee flexion angles of 0 degrees, 30 degrees, 60 degrees, and 90 degrees with the tibia in neutral and 15 degrees internal and external tibial rotation. Patellofemoral joint contact areas in specimens from men were larger at knee flexion angles greater than 30 degrees. A significant increase in mean patellofemoral contact pressures was seen for specimens from women when compared with specimens from men at 0 degrees and 30 degrees knee flexion. The knees from women also showed a greater change in contact pressures to varying vastus medialis load at knee flexion angles of 0 degrees, 30 degrees, and 60 degrees. The results of the current study indicate that there are gender differences in patellofemoral contact areas and pressures. These differences may help explain the increased incidence of patellofemoral disorders in women.  相似文献   
148.
BACKGROUND: Carcinoma of the ampulla of Vater has a more favorable prognosis, compared to other malignant tumors of the periampullary region, because it usually presents with symptoms in the early stage. However, treatment by local resection only of the ampullary carcinoma remains controversial. The aim of this study was to evaluate the treatment results of the ampulla of Vater carcinoma according to different types of operation in low-risk-group patients. METHODS: We retrospectively reviewed the medical records of 17 low-risk-group patients among a total of 102 patients with ampulla of Vater carcinoma who had underwent curative surgery from 1992 to 2002. All specimens were critically reviewed by a single expert pathologist, and the relationship between surgical outcomes and operation type was assessed. RESULTS: The low-risk group was comprised of 10 men and 7 women with a median age of 57.8 years. Thirteen of 17 patients underwent a pancreaticoduodenectomy (PD) or a pylorus preserving pancreaticoduodenectomy (PPPD), while 4 patients underwent a transduodenal local resection (TDLR). The operation time was significantly shorter in the TDLR group, compared to the PD or PPPD groups. Among the 17 patients, there was only 1 case of recurrence in the inguinal area 33 months after the pancreaticoduodenectomy. CONCLUSIONS: Transduodenal local resection is a comparable mode of operation for low-risk-group patients with Ampulla of Vater carcinoma. In particular, it is essential to evaluate the invasion depth in preoperative endoscopic ultrasonography, cell differentiation in preoperative biopsy, and positivity of resection margin accurately by using frozen section during the operation.  相似文献   
149.
150.
Background Endoscopic resection (ER) is an effective treatment for early gastric cancer (EGC) without lymph node metastasis. However, after ER additional surgery may be needed to manage the risks presented by residual cancer or lymph node metastasis. Methods ER was performed on 344 gastric adenocarcinomas between November 2001 and April 2006 at the Korean National Cancer Center under the strict pre-procedural indication. The authors performed operations in 43 patients due to: residual mucosal cancer, a mucosal cancer larger than 3 cm, or a submucosal cancer regardless of size or margin involvement. ER and surgical specimens were reviewed and analyzed for residual cancer and lymph node metastasis. Results Based on examinations of ER specimens, cancer was confined to the mucosal layer in 15 patients (34.9%) and invaded the submucosal layer in 28 patients (65.1%). Surgical specimens showed residual cancer in 17 patients (39.5%) and lymph node metastasis in four (9.3%). Neither residual cancer nor lymph node metastasis was found in patients with less than 500 μm submucosal invasion without margin involvement in ER specimens. In three of four patients with lymph node metastasis, the depth of submucosal invasion was 500 μm or more; the remaining patient had a 4-cm-sized differentiated mucosal cancer. Conclusions When a pathologic evaluation of an ER specimen reveals more than 500 μm of submucosal invasion or a mucosal cancer of larger than 3 cm, surgery should be considered due to the risk of lymph node metastasis.  相似文献   
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