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21.

Objective

Tumor enucleation has been shown to be oncologically safe for elective treatment of renal cell carcinoma (RCC); yet, evidence on long-term oncologic outcomes after robotic tumor enucleation is lacking.In this study we provide a detailed histopathological analysis of tumor–parenchyma interface and the long-term oncologic outcomes after robotic tumor enucleation for sporadic RCC in a high-volume referral center.

Materials and Methods

We selected consecutive patients undergoing robotic tumor enucleation for sporadic RCC by experienced surgeons with at least 4 years of follow-up.Pattern of pseudocapsule (PC) invasion, thickness of healthy renal margin removed with the tumor, margin status and recurrence rate were the main study endpoints. Multivariable models evaluated independent predictors of PC invasion.

Results

Overall, 140 patients were eligible for the study. Of these, 127 (91%) had complete data available for analysis. Median thickness of healthy renal margin was 0.57 mm (interquartile range [IQR] 0.24–103).A distinct peritumoral PC was present in 121/127 (95%) tumors with a median thickness of 0.28 mm (IQR 0.14–0.45).In 24/121 (19.8%) cases, RCC showed complete PC invasion. At multivariable analysis, increasing tumor diameter, endophytic rate > 50% and papillary histology were significantly associated with complete PC invasion.Positive surgical margins were reported in 3/127 (2.4%) cases. At a median follow-up of 61 months (range 48–76), one patient died due to metastatic RCC. Among patients alive at follow-up, no cases of recurrence at the enucleation site were recorded, while three cases (2.4%) of renal recurrence (elsewhere in the ipsilateral kidney) and three cases (2.4%) of systemic recurrence were found.

Conclusions

Distinct RCC-related features were associated with complete PC invasion. By providing a microscopic layer of healthy renal margin in almost all cases, robotic tumor enucleation achieved negative surgical margins in the vast majority of patients, even in case of complete PC invasion. At long-term follow-up, no recurrences were found at the enucleation site. Although our findings need to be confirmed by larger studies with longer follow-up, robotic tumor enucleation appears oncologically safe in experienced hands for the treatment of sporadic RCC.  相似文献   
22.

Objectives

The prognostic value of free to total PSA ratio (F/T PSA) in patients eligible for radical prostatectomy (RP) is controversial. The aim of the present study was to evaluate correlation of F/T PSA with tumor extracapsular extension (ECE) and biochemical recurrence (BR) at long-term follow-up.

Patient and methods

Clinical and pathological data were prospectively gathered from 200 patients treated with RP for clinically localized prostate cancer (PCa) and PSA between 4 and 10?ng/mL. Correlations of preoperative variables including F/T PSA with ECE and BR were evaluated with uni- and multivariate analysis. Adjunctive analyses evaluated the association of PSA F/T with other pathological results. The relationship between preoperative F/T PSA and BR was also assessed with Kaplan?CMeier survival analysis.

Results

Lower F/T PSA was significantly correlated with ECE (p?=?0.0063), higher GS (p?=?0.0054), and seminal vesicles involvement (p?=?0.0047). The F/T PSA value of 14% provided the greatest discrimination in predicting ECE. At multivariate analysis, F/T PSA did not achieve the statistical significance for predicting ECE independently. At a mean (median, range) follow-up of 52 (48, 14?C116) months, preoperative F/T PSA resulted significantly correlated with BR (p?=?0.001). At the Kaplan?CMeier survival analysis, the 5-year BR free survival rate resulted 89.3 and 68.9% in the group with F/T PSA?>14 and ??14?ng/mL, respectively (log rank p?=?0.0022). At Cox proportional hazard model, only ECE resulted an independent predictor of BR (R?=?2.646, p?=?0.037).

Conclusion

In patients with clinically localized PCa and PSA 4?C10?ng/ml, lower F/T PSA was significantly associated with ECE, other adverse pathologic features, and with BR at the long-term follow-up, but only ECE resulted an independent predictor of BR in our series.  相似文献   
23.

Purpose

Partial nephrectomy (PN) is standard for small renal masses, improving renal function by preserving renal parenchyma compared with radical nephrectomy. Recent work demonstrated that postoperative surgeon assessment of volume preservation (SAVP) and 3D imaging measurements agree and correlate with postoperative function. We hypothesize preoperative assessment of volume preservation (PAVP) with PN based on preoperative imaging will reliably indicate postoperative renal function.

Materials and Methods

Data were collected from 336 patients undergoing PN for suspected renal cancer by 40 surgeons at 12 centers in Europe and the United States within the Surface-Intermediate-Base International Consortium. Surgeons recorded PAVP and SAVP for individual patients; pre- and postoperative glomerular filtration rate (GFR) was estimated by Chronic Kidney Disease Epidemiology Collaboration equations. Correlations between PAVP, SAVP, and postoperative GFR were assessed with linear regression models. Bland–Altman analysis was used to assess agreement between PAVP and SAVP with a significant cutoff of 5%.

Results

Median PAVP was 90% (interquartile range [IQR] 85%–100%) and SAVP was 90% (IQR: 80%–94%). PAVP and SAVP were moderately correlated (R2?=?0.67, P < 0.0001) and deemed “interchangeable” by Bland–Altman analysis at a 5% acceptable rate of difference (95% CI: ?5.4, ?3.1). Median postoperative GFR was 77.3 (IQR: 56.2, 92.0). Both PAVP (R2?=?0.82, P < 0.0001) and SAVP (R2?=?0.83, P < 0.0001) were correlated with postoperative GFR. Multivariable models utilizing volume-adjusted GFR based on PAVP or SAVP significantly and similarly predicted postoperative GFR (R2?=?0.72 for each).

Conclusion

Renal function is closely linked to the amount of parenchymal volume preservation, whether estimated prior to surgery (PAVP) or afterward (SAVP). PAVP provides reasonably accurate information for decision-making in patients considering PN.  相似文献   
24.
Extensible endoprostheses of the humerus after resection of bone tumours   总被引:2,自引:0,他引:2  
We carried out extensible endoprosthetic replacement of the proximal or total humerus in 18 children aged between six and 12 years, after resection of primary bone tumours mainly for osteosarcoma and Ewing's sarcoma. In 11 patients we performed 44 lengthening procedures, with an average of two per child annually and a mean total extension of 29.9 mm per patient. We were able to achieve lengthening of the operated limb with few complications and a mean functional rating of 79.3% according to the Enneking system. Progressive lengthening of these prostheses does not adversely affect the overall function of the arm, and superior subluxation of the head of the prosthesis has not been a problem.  相似文献   
25.
Solitary Fibrous Tumors (SFT) are rare spindle cell neoplasm that typically originate from the pleura. However, cases of the SFT are described with origin in other organs, including the urinary and genital apparatus. Within the kidney, except from the renal pelvis, only 19 cases of SFT are described and such rarity of localization makes the histogenesis and the prognosis of the tumor rather unknown. We report the case of a 72-year-old lady who attended our Unit for a mass that was clinically palpable at the level of the left hemiabdomen. The tomodensitographic test indicated a 19cm-diameter mass of likely pertinence of the middle bystender of the left kidney. She had undergone left radical nephrectomy. The histological examination highlighted a solitary fibrous tumor (SFT): the presence of hypercellularity, of cellular pleiomorphism and of a high number of mitosis has led to a histological diagnosis of malignancy for the neoplasm analyzed. The SFT are of rare clinical comparison: this does not allow for a deep knowledge of the lesion histogenesis and prognosis; moreover, the clinical behavior should be more precisely defined.  相似文献   
26.
Pentachlorophenol (PCP) is widely distributed and highly persistent in soil, and represents a threat to the health of ecosystems. The present study aimed to assess the toxicity and bioavailability of PCP in soils as a function of different aging periods with the attempt to select a good toxicological assay for Eisenia andrei Bouché (Annelida: Lumbricidae). The experiments were performed on soil contaminated with PCP at 15 and 150ppm. After different aging periods (20, 60 and 120 days from spiking), bioavailability and toxicity were evaluated on E. andrei kept for 7 and 14 days in treated soils. The actual bioavailability decreased in relation to the aging for both PCP concentrations. No membrane damage was observed on coelomocytes collected by ethanol extrusion. Modifications in distribution of coelomocyte subpopulations were detected by flow cytometry on samples aged for 60 and 120 days at 150ppm PCP contamination. The reduction of lysosomal membrane stability, measured by neutral red retention time, was observed in all treatments. Worm mortality increased with aging in soils spiked with 150ppm of PCP. In conclusion, aging did not seem to reduce PCP cytotoxicity. This is the first report on in vivo toxicity of PCP evaluated on coelomocytes of E. andrei using different assays.  相似文献   
27.
A technique that allows a safer use of the pursestring applicator in stapled esophagojejunostomy is described. By means of five stitches, all esophageal layers are incorporated in the stapled line. Thus, missing a segment of esophageal mucosal layer is avoided. No clinical or radiologic leak was observed in 48 patients who underwent total gastrectomy using this technique.  相似文献   
28.
OBJECTIVE: The purpose of this study was to investigate the efficacy of temporin A as a prophylactic agent in a rat model of vascular graft infection from methicillin sodium-susceptible and methicillin sodium-resistant Staphylococcus epidermidis. METHODS: The prospective, randomized, controlled animal study set in a research laboratory in a university hospital used 280 adult male Wistar rats (weight range, 280 to 350 g). Graft infections were established in the back subcutaneous tissue of rats with implantation of 1-cm(2) sterile Dacron grafts followed by topical inoculation with 2 x 10(7) colony-forming units of S epidermidis. The study for each staphylococcal strain included: one control group (no graft contamination), one contaminated group that did not receive any antibiotic prophylaxis, one contaminated group that received temporin A-soaked graft, two contaminated groups that received perioperative intraperitoneal cefazolin (30 mg/kg) or vancomycin hydrochloride prophylaxis (10 mg/kg), and two contaminated groups that received temporin A-soaked graft and perioperative intraperitoneal cefazolin (30 mg/kg) or vancomycin hydrochloride (10 mg/kg) prophylaxis. All grafts were explanted at 7 days after implantation. The main outcome measure was quantification of bacterial contamination. RESULTS: Overall, the perioperative prophylaxis based on soaked grafts was not significantly different to that of parenteral vancomycin hydrochloride. Only the combination between temporin A and vancomycin hydrochloride produced a complete bacterial inhibition for both strains. CONCLUSION: Temporin A showed a similar antibacterial in vitro activity against the two different strains. The in vivo results suggest its potential use in providing prophylaxis to direct graft contamination when used in combination with parenteral vancomycin hydrochloride.  相似文献   
29.
OBJECTIVE: To evaluate serum levels of relaxin (RLX), a hormone with acknowledged antifibrotic activity, in patients with systemic sclerosis (SSc). METHODS: We performed a pilot study of 50 outpatients with SSc and 50 healthy subjects. Serum RLX was measured using the relaxin ELISA. Statistical analysis was performed using Student's t test. RESULTS: Serum RLX appeared to be significantly higher (p < 0.001) in patients with SSc compared to controls. RLX appeared significantly increased (p < 0.001) in male patients compared to male controls, and in female patients compared to female controls. RLX was significantly higher (p < 0.001) in female patients and female controls compared to male patients and male controls. CONCLUSION: In patients with SSc, the increased level of RLX represents a defensive response against the fibrotic process.  相似文献   
30.
Little is known about prokaryotic homologs of Cu,Zn superoxide dismutase (SOD), an enzyme highly conserved among eukaryotic species. In 138 Archaea and Bacteria genomes, 57 of these putative homologs were found, 11 of which lack at least one of the metal ligands. Both the solution and the crystal structures of the SOD-like protein from Bacillus subtilis, lacking two Cu ligands and found to be enzymatically inactive, were determined. In solution, the protein is monomeric. The available nuclear Overhauser effects, together with chemical-shift index values, allowed us to define and to recognize the typical Cu,Zn SOD Greek beta-barrel but with largely unstructured loops (which, therefore, sample a wide range of conformations). On the contrary, in the crystal structure (obtained in the presence of slight excess of Zn), the protein is well structured and organized in covalent dimers held by a symmetric bridge consisting of a Zn ion bound to an Asp-His dyad in a tetrahedral geometry. Couples of dimers held by hydrophobic interactions and H bonds are further organized in long chains. The order/disorder transition is discussed in terms of metal binding and physical state.  相似文献   
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