4 resultados para Classification and Regression Trees

em Université de Lausanne, Switzerland


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Objective: Because increasing incidence of melanoma and dermatologicsystematic screening, more early superficial melanoma are discovered in Switzerland. Patients with Breslow index more than 1 mm. (T2) represent the classical indication to sentinel node (SN). It has been shown that some ''risky'' T1 patients may have micrometastatic SNs. T1b melanoma are defined by presence of ulceration,Clark IV (ormore) level, signs of melanoma regression (old classification) and high mitotic index (new TNM). The objective of the present study was to review the incidence and risk for metastatic SN in T1 patients and if radical lymph node dissection is justified (evaluation of non sentinel node [NSN]) compared with T2-4 patients.Methods: Retrospective review of a cohort of all patients operated for T1-4 clinically N0 and radiological M0 melanoma patients between 1997 and 2010 in a reference melanoma centre.Results: 599 melanoma patients have been operated with SNdissection. There were 98 T1 patients. Metastatic SN were observed in 2 out of 24 T1a patients and in 5 out of 74 T1b patients. This means overall 7% T1 patients were at least N1a. None of SN+ T1a or T1b patients had metastatic NSN after radical lymph node dissections (RLND). During the follow-up (1998-2010), no patients presented with locoregional disease and only one T1a N1a patient died of metastatic melanoma. These results contrast with the other 591 T2-4 patients: 150 were SN+ (25%) and among them 23 had metastatic NSN after RLND. Overall 23/136 (17%) had metastatic NSN.Conclusion: T1 melanoma patients are at significant risk (7%) for metastatic lymph node in the corresponding drainage basin. T1a and T1b did not differ regarding this risk. However, the benefit for a RLND must be reevaluated regarding surgical morbidity, because none of T1 patients had metastatic NSN.

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Phthalates are suspected to be endocrine disruptors. Di(2-ethylhexyl) phthalate (DEHP) is assumed to have low dermal absorption; however, previous in vitro skin permeation studies have shown large permeation differences. Our aims were to determine DEHP permeation parameters and assess extent of skin DEHP metabolism among workers highly exposed to these lipophilic, low volatile substances. Surgically removed skin from patients undergoing abdominoplasty was immediately dermatomed (800 μm) and mounted on flow-through diffusion cells (1.77 cm(2)) operating at 32°C with cell culture media (aqueous solution) as the reservoir liquid. The cells were dosed either with neat DEHP or emulsified in aqueous solution (166 μg/ml). Samples were analysed by HPLC-MS/MS. DEHP permeated human viable skin only as the metabolite MEHP (100%) after 8h of exposure. Human skin was able to further oxidize MEHP to 5-oxo-MEHP. Neat DEHP applied to the skin hardly permeated skin while the aqueous solution readily permeated skin measured in both cases as concentration of MEHP in the receptor liquid. DEHP pass through human skin, detected as MEHP only when emulsified in aqueous solution, and to a far lesser degree when applied neat to the skin. Using results from older in vitro skin permeation studies with non-viable skin may underestimate skin exposures. Our results are in overall agreement with newer phthalate skin permeation studies.

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Verrucous carcinoma of the vulva is a rare lesion (1). Affecting essentially postmenopausal women, this lesion is a distinct and particular entity in vulval carcinoma classification and its scalability is uncertain and unpredictable. Here, we present a case concerning a 48-year-old patient, without follow-up after a condyloma acuminate of the vulva (large left lip). The origin of this case will be discussed in this article. The treatment decided was only surgical. A review of literature shows the rarity of this lesion of the female genital tract.