969 resultados para Melanocytic Skin-cancer
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The management of lymph nodes in nonmelanoma skin cancer patients is currently still debated. Merkel cell carcinoma (MCC), squamous cell carcinoma (SCC), pigmented epithelioid melanocytoma (PEM), and other rare skin neoplasms have a well-known risk to spread to regional lymph nodes. The use of sentinel lymph node biopsy (SLNB) could be a promising procedure to assess this risk in clinically N0 patients. Metastatic SNs have been observed in 4.5-28% SCC (according to risk factors), in 9-42% MCC, and in 14-57% PEM. We observed overall 30.8% positive SNs in 13 consecutive patients operated for high-risk nonmelanoma skin cancer between 2002 and 2011 in our institution. These high rates support recommendation to implement SLNB for nonmelanoma skin cancer especially for SCC patients. Completion lymph node dissection following positive SNs is also a matter of discussion especially in PEM. It must be remembered that a definitive survival benefit of SLNB in melanoma patients has not been proven yet. However, because of its low morbidity when compared to empiric elective lymph node dissection or radiation therapy of lymphatic basins, SLNB has allowed sparing a lot of morbidity and could therefore be used in nonmelanoma skin cancer patients, even though a significant impact on survival has not been demonstrated.
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The serotonin-2A receptor (5-HT(2A)R) has been implicated in the pathogenesis of schizophrenia and related inhibitory gating and behavioral inhibition deficits of schizophrenia patients. The hallucinogen psilocybin disrupts automatic forms of sensorimotor gating and response inhibition in humans, but it is unclear so far whether the 5-HT(2A)R or 5-HT(1A)R agonist properties of its bioactive metabolite psilocin account for these effects. Thus, we investigated whether psilocybin-induced deficits in automatic and controlled inhibition in healthy humans could be attenuated by the 5-HT(2A/2C)R antagonist ketanserin. A total of 16 healthy participants received placebo, ketanserin (40 mg p.o.), psilocybin (260 μg/kg p.o.), or psilocybin plus ketanserin in a double-blind, randomized, and counterbalanced order. Sensorimotor gating was measured by prepulse inhibition (PPI) of the acoustic startle response. The effects on psychopathological core dimensions and behavioral inhibition were assessed by the altered states of consciousness questionnaire (5D-ASC), and the Color-Word Stroop Test. Psilocybin decreased PPI at short lead intervals (30 ms), increased all 5D-ASC scores, and selectively increased errors in the interference condition of the Stroop Test. Stroop interference and Stroop effect of the response latencies were increased under psilocybin as well. Psilocybin-induced alterations were attenuated by ketanserin pretreatment, whereas ketanserin alone had no significant effects. These findings suggest that the disrupting effects of psilocybin on automatic and controlled inhibition processes are attributable to 5-HT(2A)R stimulation. Sensorimotor gating and attentional control deficits of schizophrenia patients might be due to changes within the 5-HT(2A)R system.
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Cancer pain significantly affects the quality of cancer patients, and current treatments for this pain are limited. C-Jun N-terminal kinase (JNK) has been implicated in tumor growth and neuropathic pain sensitization. We investigated the role of JNK in cancer pain and tumor growth in a skin cancer pain model. Injection of luciferase-transfected B16-Fluc melanoma cells into a hindpaw of mouse induced robust tumor growth, as indicated by increase in paw volume and fluorescence intensity. Pain hypersensitivity in this model developed rapidly (<5 days) and reached a peak in 2 weeks, and was characterized by mechanical allodynia and heat hyperalgesia. Tumor growth was associated with JNK activation in tumor mass, dorsal root ganglion (DRG), and spinal cord and a peripheral neuropathy, such as loss of nerve fibers in the hindpaw skin and induction of ATF-3 expression in DRG neurons. Repeated systemic injections of D-JNKI-1 (6 mg/kg, i.p.), a selective and cell-permeable peptide inhibitor of JNK, produced an accumulative inhibition of mechanical allodynia and heat hyperalgesia. A bolus spinal injection of D-JNKI-1 also inhibited mechanical allodynia. Further, JNK inhibition suppressed tumor growth in vivo and melanoma cell proliferation in vitro. In contrast, repeated injections of morphine (5 mg/kg), a commonly used analgesic for terminal cancer, produced analgesic tolerance after 1 day and did not inhibit tumor growth. Our data reveal a marked peripheral neuropathy in this skin cancer model and important roles of the JNK pathway in cancer pain development and tumor growth. JNK inhibitors such as D-JNKI-1 may be used to treat cancer pain.
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BACKGROUND: Exposure to solar ultraviolet (UV) light is the main causative factor for skin cancer. Outdoor workers are at particular risk because they spend long working hours outside, may have little shade available and be bound to take their lunch at their workplace. Despite epidemiological evidence of a doubling in risk of squamous cell carcinoma in outdoor workers, the recognition of skin cancer as an occupational disease remains scarce. OBJECTIVE: To assess occupational solar UV doses and its contribution to skin cancer risk. METHODS: A numerical model (SimUVEx) was used to assess occupational and lunch break exposures, characterize exposure patterns and anatomical distribution. Risk of squamous cell carcinoma (SCC) was estimated from an existing epidemiological model. RESULTS: Horizontal body locations received 2.0-2.5 times more UV than vertical locations. Dose associated to lunch outdoor every day was similar to outdoor work one day per week but only half of a seasonal worker. Outdoor workers are associated with an increased risk of SCC but also of frequent acute episodes. CONCLUSION: Occupational solar exposure contributes largely to the overall lifetime UV dose, resulting in an excess risk of SCC. The magnitude of the estimated excess in risk supports the recognition of SCC as an occupational disease.
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Swiss clinical practice guidelines for skin cancer in organ transplant recipients Transplant patients have increased over the last decades. As a consequence of long-term immunosuppression, skin cancer, in particular squamous cell carcinoma (SCC), has become an important problem. Screening and education of potential organ transplant recipients (OTRs) regarding prevention of sun damage and early recognition of skin cancer are important before transplantation. Once transplanted, OTRs should be seen yearly by a dermatologist to ensure compliance with sun avoidance as well as for treatment of precancerosis and SCC. Early removal is the best treatment for SCC. Reduction of immunosuppression, switch to mTOR inhibitors and chemoprevention with acitretin may reduce the incidence of SCC. The dermatological follow-up of OTRs should be integrated into a comprehensive post-transplant management strategy.
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Excessive exposure to uv light initiates melanoma in the skin. Tumour-specific enzymes are hijacked to deliver anticancer drugs.
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Photodynamic therapy (PDT) is based on the association of a light source and tight sensitive agents in order to cause the selective death of tumor cells. To evaluate topical 5-aminolaevulinic acid (5-ALA) and diode laser photodynamic single session therapy single session for non-melanoma skin cancer (NMSC), a long-term follow-up was performed. Nineteen Bowen`s disease (BD) and 15 basal cell. carcinoma (BCC) lesions were submitted to 6-h topical and occlusive 20% 5-ALA plus DMSO and EDTA, and later were exposed to 630 nm diode laser, 100 or 300 J cm(-2) dose. At 3 months tumor-free rate was 91.2% (31/34) whereas at 60 months, 57.7% (15/26), slightly higher in BCC (63.6%; 7/11). The relation between the reduction of the clinical response and the increase of tumor dimension observed at 18 months was lost at 60 months. The sBCC recurrence was earlier compared to the nBCC one. ALA-PDT offered important advantages: it is minimally invasive, an option for patients under risk of surgical complications; clinical feasibility; treatment of multiple lesions in only one session or lesions in poor heating sites and superior esthetical results. However, the recurrence rate increase after ALA-PDT diode laser single session can be observed at tong-term follow-up, and the repetitive sessions, an additional. advantage of the method, is strongly recommended. The clinical response and recurrence time seem to be related to the laser light dose and NMSC types/sub-types, thickness and dimension, which must be considered for the choice of the ALA-PDT. (C) 2009 Elsevier B.V. All rights reserved.
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Manifestações cutâneas pré-neoplásicas e neoplásicas em asiáticos são infreqüentes e pouco documentadas. O Brasil possui o maior contingente de imigrantes japoneses e 70% deles residem no Estado de São Paulo. A prevalência dessas lesões em nipo-brasileiros é desconhecida. O presente estudo tem como objetivo avaliar a prevalência de queratoses actínicas e tumores cutâneos não melanomas em nipo-brasileiros acima de trinta anos de 1ª geração ou 2ª geração, sem miscigenação, residentes na cidade de Bauru, no ano de 2006. Dos 567 nipo-brasileiros submetidos a exame dermatológico, diagnosticou-se queratose actínica em 76 pacientes, com média de idade de 68,9 anos, e único carcinoma basocelular em paciente do sexo feminino de 39 anos. No Japão, a prevalência de queratose actínica é de 0,76% a 5% e a incidência de tumores cutâneos não melanomas é de 1,2 a 5,4/100 mil. Os nipo-brasileiros de Bauru apresentaram prevalência de 13,4% de queratoses actínicas e idade mais precoce de aparecimento. Proximidade com o Equador e atividades rurais contribuem para esses achados. A presença de melanose solar demonstrou risco 1,9 vez maior de desenvolver queratose actínica.
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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
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Abstract Background Photodynamic therapy (PDT) using 5-aminolevulinic acid (5-ALA) is a skin cancer therapy that still has limitations due to the low penetration of this drug into the skin. We have proposed in this work a delivery system for 5-ALA based on liposomes having lipid composition similar to the mammalian stratum corneum (SCLLs) in order to optimize its skin delivery in Photodynamic Therapy (PDT) of skin cancers. Methods SCLLs were obtained by reverse phase evaporation technique and size distribution of the vesicles was determinated by photon correlation spectroscopy. In vitro permeation profile was characterized using hairless mouse skin mounted in modified Franz diffusion cell. Results Size exclusion chromatography on gel filtration confirmed vesicle formation. SCLLs obtained by presented a degree of encapsulation of 5-ALA around 5.7%. A distribution of vesicle size centering at around 500 nm and 400 nm respectively for SCLLs and SCLLs containing 5-ALA was found. In vitro 5-ALA permeation study showed that SCLLs preparations presented higher skin retention significantly (p < 0.05) on the epidermis without SC + dermis, with a decreasing of skin permeation compared to aqueous solution. Conclusions The in vitro delivery performance provided by SCLLs lead to consider this systems adequate for the 5-ALA-PDT of skin cancer, since SCLLs have delivered 5-ALA to the target skin layers (viable epidermis + dermis) to be treated by topical PDT of skin cancer.
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Conventional skin cancer prevention programs appeal to limited populations, and the middle aged male population responds less frequently. Our objective was to establish a complementary health promotion campaign tool for skin cancer prevention. Internet-based education, instruction for self assessment and teledermatological evaluation of skin lesions by an expert commission of dermatologists was used. Compliance and clinical diagnosis was assessed in a subgroup. 12,000 users visited the educational website. There was strong interest among the middle aged male population (53% (N = 262): male; mean age: 42). 28.5% of examined lesions (N = 494) were considered suspicious. Email requests, sent to the group whose lesions where considered suspicious, were answered by 46.0% of females (N = 29) and 59.7% of males (N = 46) with a female distribution predominantly in younger ages (52.6% of females with known age: < 30 years). Males were predominantly represented over 30 years (86.2% of all males). According to user's declarations, at least 8 (8.5%) malignant lesions (1 melanoma in situ, 1 squamous cell carcinoma, 4 basal cell carcinomas, 2 malignant lesions without declared diagnosis) were finally diagnosed by physicians. We conclude that internet-based, interactive, educational programs, in addition to existing health promotion campaigns, can enhance public participation in the middle aged male population in skin cancer prevention.
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Non-melanoma skin cancers (NMSCs) are the most common malignancies after solid organ transplantation. Their incidence increases with time after transplantation. Calcineurin-inhibitors (CNIs) and azathioprine are known as skin neoplasia-initiating and -enhancing immunosuppressants. In contrast, increasing clinical experience suggests a relevant antiproliferative effect of mammalian target of rapamycin inhibitors, also named proliferation signal inhibitors (PSIs). We report the case of a cardiac allograft recipient with an impressive and consolidated reduction of recurrent NMSC, observed after conversion from CNI-therapy to a PSI-based protocol.
Resumo:
Swiss clinical practice guidelines for skin cancer in organ transplant recipients Transplant patients have increased over the last decades. As a consequence of long-term immunosuppression, skin cancer, in particular squamous cell carcinoma (SCC), has become an important problem. Screening and education of potential organ transplant recipients (OTRs) regarding prevention of sun damage and early recognition of skin cancer are important before transplantation. Once transplanted, OTRs should be seen yearly by a dermatologist to ensure compliance with sun avoidance as well as for treatment of precancerosis and SCC. Early removal is the best treatment for SCC. Reduction of immunosuppression, switch to mTOR inhibitors and chemoprevention with acitretin may reduce the incidence of SCC. The dermatological follow-up of OTRs should be integrated into a comprehensive post-transplant management strategy.