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101.

Purpose

BRAF V600 mutations are frequent in melanomas, and BRAFV600-targeted therapy have dramatic, but often transitory, efficacy in stage IV patients. Prognosis of patients with American Joint Committee on Cancer (AJCC) stage III melanoma is heterogeneous. We aimed to determine the overall survival (OS) of stage III patients with a nodal deposit of ??2?mm according to BRAF V600 mutations and other previously reported prognostic criteria.

Methods

This retrospective study included 105 consecutive patients with stage III cutaneous melanomas. Most patients underwent a prospective follow-up. BRAF V600 mutations were detected by sequencing and pyrosequencing of DNA in samples containing >60?% melanoma cells.

Results

BRAF mutations (p.V600E and p.V600K in 83 and 14?% of cases, respectively) were detected in 40?% of the patients. For patients with and without BRAF mutations, death occurred in 83.3 and 60.3?%, with a median OS of 1.4 and 2.8?years, respectively. Patient age, primary melanoma ulceration, number of invaded lymph nodes, AJCC staging at study entry, and BRAF status were linked to OS in the univariate analysis. The only characteristics associated with OS in the multivariate analysis were number of invaded lymph nodes (P?=?0.005, hazard ratio 2.2, 95?% confidence interval 1.3?C3.9) and BRAF status (P?=?0.005, hazard ratio 1.9, 95?% confidence interval 1.2?C3.1).

Conclusions

BRAF V600 status could be used to stage melanoma patients with nodal deposits. Our results may also help to plan adjuvant trials in these patients, for whom the low tumor load may induce longer efficacy of BRAF-targeted therapies.  相似文献   
102.
Freyria AM  Mallein-Gerin F 《Injury》2012,43(3):259-265
Articular cartilage is easily injured but difficult to repair and cell therapies are proposed as tools to regenerate the defects in the tissue. Both differentiated chondrocytes and adult mesenchymal stem cells (MSCs) are regarded as cells potentially able to restore a functional cartilage. However, it is a complex process from the cell level to the tissue end product, during which growth factors play important roles from cell proliferation, extracellular matrix synthesis, maintenance of the phenotype to induction of MSCs towards chondrogenesis. Members of the TGF-β superfamily, are especially important in fulfilling these roles. Depending on the cell type chosen to restore cartilage, the effect of growth factors will vary. In this review, the roles of these factors in the maintenance of the chondrocyte phenotype are discussed and compared with those of factors involved in the repair of cartilage defects, using chondrocytes or adult mesenchymal stem cells.  相似文献   
103.

Purpose

The aim of this pilot study was to describe the hydration and nutritional status of a cohort of elderly dialysis patients and to explore the association between these parameters and the quality of life (QoL).

Methods

All patients over 75?years of age being in chronic dialysis by January 2008 at 3 dialysis units (n?=?34) were asked to participate in this pilot study, 24 patients were entered. Hydration status was assessed by bioimpedance spectroscopy (BIS) and nutritional status by the subjective global assessment (SGA), BIS, anthropometric measures and biochemical parameters. Based on these assessments the patients were classified as being cachectic or not according to newly defined criteria. QoL was measured using the SF-36.

Results

The results showed cachexia in 6 (25?%), 37.5?% had a body mass index below 24, whereas according to SGA 91?% were malnourished. BIS showed low lean tissue index in 46?% and overhydration in 35?% of the patients. Compared to non-cachectic and normohydrated, cachectic and overhydrated patients reported consistently poorer QoL. For cachectic patients, the differences were clinically significant for all SF-36. BIS was easily applicable when used before dialysis.

Conclusions

The high frequency of nutritional deficits in this study calls for more attention to nutritional status in elderly dialysis patients. There is a need for a general agreement on how nutritional status should be assessed and reported, both in clinics and in research.  相似文献   
104.
Although optical colonoscopy is still the gold standard for diseases of the colon, radiologic examination of the colon is now being performed by CT scan. Evaluation of the colon is enhanced by distension, which "de-folds" the intestinal wall, thus facilitating its examination for abnormalities of the mucosa, the wall as a whole, and the diameter of the bowel lumen. Water or gas (CO(2)) may be used for the distension, depending on the suspected lesions. The water enema method of colonography combines filling the bowel lumen with water and intravenous injection of a contrast medium. It is indicated when there is a clinical suspicion of colon cancer, or for initial discovery of liver metastases, and for staging of colon tumors. This technique, which requires little or no colon cleansing preparation, can be performed with no special equipment and has a short learning curve. The gas enema method of colonography, or virtual colonoscopy, is performed by distending the colon with CO(2), without any intravenous injection of contrast medium. Its purpose is to detect polyps as part of a screening for precancerous growths. This technique, which does require bowel cleansing preparation, uses a dedicated console for reading and requires specific training.  相似文献   
105.

Background

Technetium Tc 99m bone scintigraphy (BS) and contrast-enhanced computed tomography (CT) or magnetic resonance imaging (MRI) of the pelvis and abdomen are universally recommended for detecting prostate cancer (PCa) metastases in cancer of all stages. However, this two-step approach has limited sensitivity and specificity.

Objective

Evaluate the diagnostic accuracy of whole-body MRI (WBMRI) as a one-step screening test for PCa metastases.

Design, setting, and participants

One hundred consecutive PCa patients at high risk for metastases prospectively underwent WBMRI, CT, and BS completed with targeted x-rays (BS/TXR) in case of equivocal BS. Four independent reviewers reviewed the images.

Measurements

This study compares the diagnostic performance of WBMRI, CT, BS, and BS/TXR in detecting PCa metastases using area under the curve (AUC) receiver operator characteristics. A best valuable comparator (BVC) approach was used to adjudicate final metastatic status in the absence of pathologic evaluation.

Results and limitations

Based on the BVC, 68 patients had metastases. The sensitivity of BS/TXR and WBMRI for detecting bone metastases was 86% and 98–100%, respectively (p < 0.04), and specificity was 98% and 98–100%, respectively. The first and second WBMRI readers respectively identified bone metastases in 7 and 8 of 55 patients with negative BS/TXR. The sensitivity of CT and WBMRI for detecting enlarged lymph nodes was similar, at 77–82% for both; specificity was 95–96% and 96–98%, respectively. The sensitivity of the combination of BS/TXR plus CT and WBMRI for detecting bone metastases and/or enlarged lymph nodes was 84% and 91–94%, respectively (p = 0.03–0.10); specificities were 94–97% and 91–96%, respectively. The 95% confidence interval of the difference between the AUC of the worst WBMRI reading and the AUC of any of the BS/TXR plus CT lay within the noninferiority margin of ±10% AUC.

Conclusions

WBMRI outperforms BS/TXR in detecting bone metastases and performs as well as CT for enlarged lymph node evaluation. WBMRI can replace the current multimodality metastatic work-up for the concurrent evaluation of bones and lymph nodes in high-risk PCa patients.  相似文献   
106.
Study Type – Therapy (multi‐centre retrospective cohort) Level of Evidence 2b What's known on the subject? and What does the study add? Upper urinary tract urothelial carcinomas (UUT‐UCs) are rare tumours. Because of the aggressive pattern of UC, radical nephroureterectomy (RNU) with bladder cuff removal remains the ‘gold‐standard’ treatment. However, conservative strategies, such as segmental ureterectomy (SU) or endourological management, have also been developed in patients with imperative indications. Some teams are now advocating the use of conservative management more commonly in cases of elective indications of UUT‐UCs. Due to the paucity of cases of UUT‐UC, only limited data are available on the oncological outcomes afforded by conservative management. We retrospectively investigated the oncological outcomes after SU and RNU in a large multi‐institutional database. Overall, 52 patients were treated with SU and 416 with RNU. There was no statistical difference between the RNU and SU groups for the 5‐year probability of cancer‐specific survival, recurrence‐free survival and metastasis‐free survival. The type of surgery was not a significant prognostic factor in univariate analysis. The results were the same in a subgroup analysis of only unifocal tumours of the distal ureter with a diameter of <2 cm and of low stage (≤T2). Our results suggest that oncological outcomes after conservative treatment with SU are comparable to RNU for the management of UUT‐UC in select cases.

OBJECTIVE

  • ? To compare recurrence‐free survival (RFS), metastasis‐free survival (MFS) and cancer‐specific survival (CSS) after segmental ureterectomy (SU) vs radical nephroureterectomy (RNU) for urothelial carcinoma (UC) of the upper urinary tract (UUT‐UC) located in the ureter.

PATIENTS AND METHODS

  • ? We performed a multi‐institutional retrospective review of patients with UUT‐UC who had undergone RNU or SU between 1995 and 2010.
  • ? Type of surgery, Tumour‐Node‐Metastasis status, tumour grade, lymphovascular invasion and positive surgical margin were tested as prognostic factors for survival.

RESULTS

  • ? In all, 52 patients were treated with SU and 416 with RNU. The median (range) follow‐up was 26 (10–48) months.
  • ? The 5‐year probability of CSS, RFS and MFS for SU and RNU were 87.9% and 86.3%, respectively (P= 0.99); 37% and 47.9%, respectively (P= 0.48); 81.9% and 85.4%, respectively (P= 0.51).
  • ? In univariable analysis, type of surgery (SU vs RNU) failed to affect CSS, RFS and MFS (P= 0.94, 0.42 and 0.53, respectively).
  • ? In multivariable analyses, pT stage and pN stage achieved independent predictor status for CSS (P= 0.005 and 0.007, respectively); the positive surgical margin and pT stage were independent prognostic factors of RFS and MFS (P= 0.001, 0.04, 0.009 and 0.001, respectively).
  • ? The main limitation of the study is its retrospective design, which is due to the rarity of the disease.

CONCLUSIONS

  • ? Short‐term oncological outcomes after conservative treatment with SU are comparable to RNU for the management of UUT‐UC in select cases and should be considered an option.
  • ? In every other case, RNU still represents the ‘gold standard’ for the treatment of UUT‐UC.
  相似文献   
107.
The increasing use of digitally formatted imaging systems requires high-quality interactive gray-scale computer raster graphics systems for the management, display, and analog film recording of digital image and alphanumeric information. These systems are a combination of computer hardware and software and implement a set of graphics protocols. This paper describes a set of interactive graphics protocols that has been developed for clinical use.  相似文献   
108.

Background

Dual mobility (DM) cups of mobile polyethylene were introduced to prevent total hip arthroplasty (THA) dislocation, but no large series with this design to treat recurrent instability have been reported.

Purpose

Our retrospective investigation ascertained the efficiency of DM cups in correction of recurrent dislocation and assessed any adverse effects.

Methods

One hundred eighty THAs with recurrent instability were revised to DM cups in 180 patients (mean age, 67.4 ± 11.7 years; range, 19 to 92 years). Thirty-one patients (17.2%) underwent at least one earlier THA revision, and 15 (10.3%) incurred non-union of the greater trochanter. Of the initial group in 2009, 145 patients had completed evaluations which included assessment of the Harris Hip Score and a radiographic assessment at a mean follow-up of 7.7 ± 2.2 years (range, 4 to 14 years). The rate of survival was calculated considering any reason for revision as failure.

Results

At follow-up, Harris hip score was 83.9 ± 16.1 (range, 21 to 100). Dislocation of the large articulation occurred in seven hips (4.8%), and only two recurred (1.4%) (one requiring additional revision). In addition, two intra-prosthetic dislocations of the small articulation (1.4%) were observed and needed revision surgery. The large number of earlier surgeries and non-union of the greater trochanter were related to recurrent instability. Two cups (1.4%) showed signs of definite loosening; six (4.1%) presented signs of possible loosening. Twenty-nine hips manifested femoral or acetabular osteolysis (20%), but only three were severe. Eight-year survival rate considering revision for any reason was 92.6% (95% CI, 85.5–96.4%).

Conclusions

This series indicates that DM cups are a viable option to treat recurrent THA instability. Their design provides a low risk of recurrent instability without increasing mechanical complications.  相似文献   
109.
OBJECTIVE: Calcium and vitamin D deficiency is common in older individuals, particularly those who live in nursing homes, and increases the risk of osteoporosis and fractures. METHODS: We conducted a randomized double-blind placebo-controlled study of combined supplementation with 500 mg of elemental calcium, as carbonate, and 400 IU of vitamin D bid for 12 months in women older than 65 years of age with vitamin D deficiency, defined as serum 25(OH)D concentrations 相似文献   
110.
BACKGROUND: Routine cytomegalovirus (CMV)-pp65 antigenaemia monitoring shows that some patients will develop pp65 antigenaemia during valaciclovir prophylaxis or after cessation of treatment. The aim of this pilot study was to evaluate the safety and efficacy of lowering immunosuppression in kidney transplant recipients who exhibit mildly symptomatic CMV infections while on valaciclovir prophylaxis. METHODS: We selected 12 patients who experienced mildly symptomatic CMV infections defined as a positive CMV-pp65 antigenaemia test associated with either neutropenia, asthenia or arthralgia, but no fever. All of them received prophylaxis with valaciclovir for at least 3 months. Testing for CMV-pp65 antigenaemia was performed weekly for 6 months. RESULTS: The mildly symptomatic infections occurred at a median interval of 69 days after transplantation-during prophylaxis in eight cases and after valaciclovir discontinuation in the other four cases. All of them were effectively managed by lowering immunosuppressive therapy, leading to the disappearance of symptoms and CMV antigenaemia reduction. No immunological complication or recurrence of CMV infection or disease was noted. I.v. ganciclovir never became necessary. CONCLUSION: The mildly symptomatic CMV infections occurring in valaciclovir-treated patients may be managed efficiently and without immunologic complication by lowering immunosuppressive therapy.  相似文献   
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