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991.
Background We compared outcomes of surgery and radiofrequency thermal ablation (RFA) in patients with metachronous liver metastases. Methods Between October 1995 and December 2005, 59 patients underwent hepatic resection and 30 underwent RFA for metachronous liver metastases. Patients with extra-hepatic metastases, those who underwent both types of treatment, and those with synchronous hepatic metastasis were excluded. Results The two groups had similar mean age, sex ratio, comorbid medical conditions, primary disease stage, and frequency of solitary metastases. Preoperative mean serum carcinoembryonic antigen (CEA) level was significantly higher in the RFA group (13.4 ng/mL vs. 7.7 ng/mL; p = 0.02). Mean diameter of hepatic metastases was significantly greater in the resection than in the RFA group (3.1 cm vs. 2.0 cm; p = 0.001). Recurrence after treatment of metastasis was observed in 18 of 30 (60.0%) RFA and 33 of 59 (56%) resection patients. Local recurrence at the RFA site was observed in 7 of 30 (23%) patients. Time to recurrence (15 vs. 8 months, p = 0.02) and overall survival (56 vs. 36 months, p = 0.005) were significantly longer in the resection than in the RFA group. In the 69 patients with solitary metastases of diameter ≤3 cm, time to recurrence (p = 0.004) and overall survival were significantly greater in the resection group. Conclusions Compared with hepatic resection, RFA for metachronous hepatic metastases from colorectal cancer was associated with higher local recurrence and shorter recurrence-free and overall survival rates, even in patients with solitary, small (≤3 cm) lesions.  相似文献   
992.
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   
993.
Centralization of referred pain or failure to centralize has in earlier studies been shown to be a predictor of low back pain prognosis. Research suggests that there are differences in how males and females experience pain. The aim of this study was to evaluate the outcome after 1 year, and to evaluate the prognostic value of the pain response in a mechanical test at the first consultation at a spine clinic, and the influence of gender, in order to identify patients with especially high risk of chronicity. The patients in this study were low back pain patients, included consecutively from a spine clinic in Northern Denmark. The criteria for entering this spine clinic were neck or low back pain with radiating symptoms and a duration of 4–26 weeks, without satisfactory improvement after treatment in the primary care system. The 793 patients were categorised into four subgroups according to their pain response in a mechanical test performed at the initial examination: centralization, non-lasting centralization, peripheralization and no effect. The patients were instructed in doing specific exercises according to the test results. The four subgroups were compared after 1 year with regard to changes in back and leg pain, disability and return-to-work status. The statistical evaluation was undertaken for the study group as a whole and stratified according to gender. A significant improvement in all outcome measures was found in all the subgroups, among both men and women. There were no systematic or statistically significant differences in the prognosis between the four subgroups of patients. The proportion of Centralizers in this study was 18%. The mechanical test at baseline is important for deciding the subject-specific exercises, but when treated according to test results, the prognostic value of the test seems limited. The project is approved by the Regional Scientific Ethical Committee.  相似文献   
994.
Background We assessed whether new parameter that considers both tumor volume change and necrosis rate predicts metastasis-free survival of localized osteosarcoma patients. We also evaluated relationship between tumor volume change and necrosis rate or metastasis-free survival. Methods We retrospectively reviewed 151 patients with stage II osteosarcoma who were treated with surgery and neoadjuvant chemotherapy. The tumor volume change was measured and calculated based on pre- and postchemotherapy magnetic resonance images. The mean metastasis-free interval was 83.1 months. We calculated adjusted tumor necrosis rate as following formula: 100–(100–necrosis rate) × postchemotherapy/prechemotherapy tumor volume. Survival and logistic regression analyses were used to evaluate the correlation among size parameters, tumor necrosis rate and survival. Results The 5-year metastasis-free survival rate of 151 patients was 71.4% (95% CI, 67.7–75.1%). American Joint Committee on Cancer (AJCC) stage IIB (RR 2.27; 95% CI, 1.11–4.62; P = 0.025) and poor adjusted tumor necrosis rate (RR 2.02; 95% CI, 1.05–3.89; P = 0.035) independently correlated with metastasis-free survival period. Further, tumor volume change independently correlated with necrosis rate. Decreased tumor volume could predict good response, with sensitivity of 80.2%, specificity of 68.6%, and positive predictive value (PPV) of 74.7%. Increased or stable tumor volume could predict poor response, with sensitivity of 68.6%, specificity of 80.2%, and PPV of 75.0 %. Conclusion The necrosis rate adjusted by the tumor volume change is an independent prognostic factor in osteosarcoma. This adjusted tumor necrosis rate may serve as a basis for risk-adapted therapy in combination with other prognostic factors.  相似文献   
995.
996.
Background The aim of this study was to analyze clinical and anatomical factors affecting the pathologic quality of the resected specimen after total mesorectal excision (TME) for rectal cancer. Methods A total of 100 patients who underwent TME for mid or low rectal cancer were evaluated prospectively. MRI pelvimetry data (transverse diameter, obstetric conjugate, interspinous distance, sacrum length, and sacrum depth) were analyzed as anatomically affecting factors to postoperative specimen quality. Sex, body mass index (BMI), type of surgery, tumor size, and tumor distance from the anal verge were analyzed as clinically affecting factors. The gross judgment of resected specimen, circumferential resection margin and the number of harvested lymph nodes were used to access postoperative specimen quality. Results The univariate and multivariate analysis showed that narrow obstetric conjugate and shorter interspinous distance were related to the inadequate quality of the mesorectum in the specimen (P = 0.022, P = 0.030). Interspinous distance was a predicting factor of a positive circumferential resection margin (P = 0.007). There were no clinical factors affecting the inadequate quality of the mesorectum or positive circumferential resection margin. Moreover, there were no clinico-anatomical factors affecting the number of harvested lymph nodes after TME. Conclusion Narrow obstetric conjugate and shorter interspinous distance were factors leading to poor postoperative specimen quality. Rectal cancer patients with narrow obstetric conjugate or shorter interspinous distance should be considered as high-risk patients with regard to specimen quality, which is in turn related to oncological outcome.  相似文献   
997.
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   
998.
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   
999.
BACKGROUND CONTEXT: The publication of several recent studies showing minimal benefit for radiofrequency (RF) lumbar zygapophysial (l-z) joint denervation have led many investigators to reevaluate selection criteria. One controversial explanation for these findings is that the most commonly used cutoff value for selecting patients for l-z (facet) joint RF denervation, greater than 50% pain relief after diagnostic blocks, is too low and hence responsible for the high failure rate. PURPOSE: To compare l-z joint RF denervation success rates between the conventional greater than or equal to 50% pain relief threshold and the more stringently proposed greater than or equal to 80% cutoff for diagnostic medial branch blocks (MBB). STUDY DESIGN/SETTING: Multicenter, retrospective clinical data analysis. PATIENT SAMPLE: Two hundred and sixty-two patients with chronic low back pain who underwent l-z RF denervation at three pain clinics. OUTCOME MEASURES: Outcome measures were greater than 50% pain relief based on visual analog scale or numerical pain rating score after RF denervation persisting at least 6 months postprocedure, and global perceived effect (GPE), which considered pain relief, satisfaction and functional improvement. METHODS: Data were garnered at three centers on 262 patients who underwent l-z RF denervation after obtaining greater than or equal to 50% pain relief after diagnostic MBB. Subjects were separated into those who received partial (greater than or equal to 50% but less than 80%) and near-complete (greater than or equal to 80%) pain relief from the MBB. Outcomes between groups were compared with multivariate analysis after controlling for 14 demographic and clinical variables. RESULTS: One hundred and forty-five patients obtained greater than or equal to 50% but less than 80% pain relief after diagnostic MBB, and 117 patients obtained greater than or equal to 80% relief. In the greater than or equal to 50% group, success rates were 52% and 67% based on pain relief and GPE, respectively. Among patients who experienced greater than 80% relief from diagnostic blocks, 56% obtained greater than or equal to 50% relief from RF denervation and 66% had a positive GPE. CONCLUSIONS: Using more stringent pain relief criteria when selecting patients for l-z joint RF denervation is unlikely to improve success rates, and may lead to misdiagnosis and withholding a potentially valuable treatment from good candidates.  相似文献   
1000.
Our objective in this study was to report on the successful clinical use of a new perforator flap obtained from the proximal quarter of the anterolateral lower leg. Eight patients had the procedure either as a result of trauma (seven patients) or to treat Marjolin's ulcer (one patient). During the procedure, a line was drawn from the anterior fibular head to the anterior lateral malleolus. Then, using Doppler, a septocutaneous perforator from the fibular head to the proximal quarter point of the line was identified. The subfascial dissection was continued to the detected perforator. Along the perforator in the anterior intermuscular (peroneal) septum, a deep dissection was performed. The perforator was then separated and the flap harvested. The septocutaneous perforator was the perforator of the superficial peroneal nerve accessory artery in three cases, the perforator of the superior lateral peroneal artery in one case, and the perforator originating directly from the anterior tibial artery in four cases. Seven of eight cases were treated successfully. The results obtained were satisfactory, both aesthetically and functionally. This flap is a valuable alternative to the various perforator flaps from the lower leg. This flap has the advantage of being very thin, which makes it suitable for reconstruction of defects in the foot, ankle, pretibial area, and knee. However, one limitation of this procedure is that the diameter of the perforator was approximately 0.6-1.2 mm.  相似文献   
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