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2.
Dermatology ; 238(6): 1044-1049, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35598594

RESUMO

BACKGROUND: Photodynamic therapy (PDT) is a noninvasive treatment for patients with superficial basal-cell carcinoma (sBCC). The efficacy of PDT may vary with different photosensitizers and treatment schedules. OBJECTIVE: Our objective was to evaluate whether fractionated 5-aminolevulinic acid 20% (ALA)-PDT is superior to conventional two-stage methyl aminolevulinate (MAL)-PDT for sBCC. METHODS: We present the 5 years results of a single-blind, randomized, multicenter trial. 162 patients with a histologically confirmed primary sBCC were randomized to fractionated ALA-PDT or MAL-PDT. RESULTS: The 5-year tumor-free survival rate was 70.7% (95% CI 58.2-80.1%) for ALA-PDT and 76.5% (95% CI 64.4-85.0%) for MAL-PDT. In the first 3 years, there was no significant difference in risk of treatment failure (HR = 1.53, p = 0.283), but in the long-term, the risk of recurrence was significantly lower following MAL-PDT compared to ALA-PDT (HR = 0.125, p = 0.049). As judged by patients, the esthetic result was good-excellent in 96.8% (61/63) and 94.4% (56/59) of patients treated with ALA-PDT and MAL-PDT, respectively (p = 0.631). CONCLUSION: The long-term efficacy is significantly higher for conventional two-stage MAL-PDT than for fractionated ALA-PDT, whereas there was no significant difference in esthetic outcome between the treatments at 5 years after treatment. These results indicate that fractionated ALA-PDT offers no benefit over conventional two-stage MAL-PDT.


Assuntos
Carcinoma Basocelular , Fotoquimioterapia , Neoplasias Cutâneas , Humanos , Ácido Aminolevulínico/uso terapêutico , Fotoquimioterapia/métodos , Método Simples-Cego , Neoplasias Cutâneas/patologia , Resultado do Tratamento , Carcinoma Basocelular/tratamento farmacológico , Carcinoma Basocelular/patologia , Fármacos Fotossensibilizantes/uso terapêutico
3.
Cancers (Basel) ; 14(6)2022 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-35326659

RESUMO

Mycosis fungoides (MF) is a subtype of CTCL with a low incidence and high medical need for novel treatments. The objective of this randomized, placebo-controlled, double-blinded, first-in-human study was to evaluate safety, efficacy, cutaneous and systemic pharmacokinetics (PK) of topical bimiralisib in healthy volunteers (HVs) and MF patients. In this trial, a total of 6 HVs and 19 early-stage MF patients were treated with 2.0% bimiralisib gel and/or placebo. Drug efficacy was assessed by the Composite Assessment of Index Lesion Severity (CAILS) score, supported by objective measuring methods to quantify lesion severity. PK blood samples were collected frequently and cutaneous PK was investigated in skin punch biopsies on the last day of treatment. Local distribution of bimiralisib in HVs showed a mean exposure of 2.54 µg/g in the epidermis. A systemic concentration was observed after application of a target dose of 2 mg/cm2 on 400 cm2, with a mean Cavg of 0.96 ng/mL. Systemic exposure of bimiralisib was reached in all treated MF patients, and normalized plasma concentrations showed a 144% increased exposure compared to HVs, with an observed mean Cavg of 4.49 ng/mL and a mean cutaneous concentration of 5.3 µg/g. No difference in CAILS or objective lesion severity quantification upon 42 days of once-daily treatment was observed in the MF patient group. In general, the treatment was well tolerated in terms of local reactions as well as systemic adverse events. In conclusion, we showed that topical bimiralisib treatment leads to (i) meaningful cutaneous drug levels and (ii) well-tolerated systemic drug exposure in MF patients and (iii) a lack of clinical efficacy, in need of further exploration due to numerous unknown factors, before depreciation of topical bimiralisib as a novel therapeutic drug for CTCLs.

5.
Ned Tijdschr Geneeskd ; 1632019 07 05.
Artigo em Holandês | MEDLINE | ID: mdl-31283126

RESUMO

BACKGROUND: 'MELTUMP' (melanocytic tumour of uncertain malignant potential) is a collective category for different melanocytic tumours in which the diagnosis 'melanoma' cannot be demonstrated, but equally cannot be excluded. Since the malignant potential of these disorders is unpredictable, there is no singular approach. CASE DESCRIPTION: A 48-year-old woman attended a dermatology clinic for an atypical mole on the left lower leg. Her medical history included two previous melanomas. The mole was photographed and excised. Histopathological diagnostics showed atypical melanocytic proliferation; the abnormality was classified as a MELTUMP. Based on the photo of the mole, it was decided to perform a re-excision with a margin of 5 mm. CONCLUSION: It is recommended to obtain photographic evidence for each pigmented abnormality that is suspected of being malignant. Based on this photo, a clinical suspicion of melanoma can be assessed later. Particularly for MELTUMP patients this can be useful when determining the clinical management.


Assuntos
Melanoma/patologia , Nevo Pigmentado/patologia , Fotografação , Neoplasias Cutâneas/patologia , Tomada de Decisões , Diagnóstico Diferencial , Feminino , Humanos , Melanoma/diagnóstico , Pessoa de Meia-Idade , Nevo Pigmentado/diagnóstico , Neoplasias Cutâneas/diagnóstico
7.
Int J Radiat Oncol Biol Phys ; 99(5): 1279-1285, 2017 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-28958772

RESUMO

PURPOSE: To determine the optimal radiation dose for treatment of primary cutaneous anaplastic large cell lymphoma (C-ALCL) with solitary or localized, multifocal or recurrent skin lesions. METHODS AND MATERIALS: In this multicenter study, patients with C-ALCL who had been treated with radiation therapy (RT) between 1984 and 2016 were retrieved from the Dutch registry of cutaneous lymphomas. Distinction was made between patients first presenting with solitary or localized lesions (n=63), with multifocal skin lesions (n=6), and patients with a skin relapse (n=22). Radiation doses, treatment response, and follow-up were evaluated. Radiation doses were categorized as low-dose (≤20 Gy), intermediate-dose (21-39 Gy), and high-dose (≥40 Gy) RT. RESULTS: Of 63 patients presenting with solitary or localized skin lesions, 61 (97%) showed a complete response (CR). There were no differences in CR between low-dose (16 of 17), intermediate-dose (15 of 15), and high-dose RT (30 of 31). After a median follow-up of 46 months, 30 of 63 patients (48%) had a relapse, but in-field relapses were never observed. Six of 6 patients (100%) initially presenting with multifocal skin lesions showed a CR (3 of 3 low-dose, 2 of 2 intermediate-dose, 1 of 1 high-dose RT). After a median follow-up of 27 months, 3 of 6 patients had a relapse. Treatment of 33 skin relapses in 22 patients showed no differences in CR between low-dose (18 of 19), intermediate-dose (6 of 6), and high-dose RT (8 of 8). In the last 10 years there has been a decrease in radiation dose used in the treatment of C-ALCL. Treatment of multifocal and recurrent lesions with a dose of 8 Gy (2 × 4 Gy) resulted in CR of 17 of 18 lesions. CONCLUSIONS: Our results show that a radiation dose of 20 Gy (8 × 2.5 Gy) is effective in patients presenting with solitary or localized skin lesions. For patients with multifocal skin lesions and patients with a skin relapse, a dose of 8 Gy (2 × 4 Gy) may be sufficient.


Assuntos
Linfoma Anaplásico Cutâneo Primário de Células Grandes/radioterapia , Recidiva Local de Neoplasia/radioterapia , Neoplasias Primárias Múltiplas/radioterapia , Dosagem Radioterapêutica/normas , Neoplasias Cutâneas/radioterapia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Seguimentos , Humanos , Estimativa de Kaplan-Meier , Linfoma Anaplásico Cutâneo Primário de Células Grandes/mortalidade , Linfoma Anaplásico Cutâneo Primário de Células Grandes/patologia , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/mortalidade , Neoplasias Primárias Múltiplas/mortalidade , Neoplasias Primárias Múltiplas/patologia , Países Baixos , Neoplasias Cutâneas/mortalidade , Neoplasias Cutâneas/patologia , Resultado do Tratamento
8.
JAMA Dermatol ; 152(9): 992-1000, 2016 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-27276223

RESUMO

IMPORTANCE: Large case series suggest that patients with folliculotropic mycosis fungoides (FMF) have a worse prognosis than patients with classic mycosis fungoides (MF). However, recent studies described a subgroup of patients with FMF with a more favorable prognosis. Distinction between indolent and aggressive FMF may have important therapeutic consequences but is hampered by the inability of the current tumor-node-metastasis-blood (TNMB) staging system to classify patients with FMF in a clinically meaningful way. OBJECTIVE: To differentiate between indolent and aggressive FMF using clinicopathological criteria and to define prognostic factors in patients with FMF. DESIGN, SETTING, AND PARTICIPANTS: In this prospective cohort study, we followed 203 patients with FMF, included in the Dutch Cutaneous Lymphoma Registry between October 1985 and May 2014 at a tertiary referral center hosting the Dutch Cutaneous Lymphoma Registry. Overall, 220 patients with FMF had been registered, but 17 patients with incomplete follow-up data or a history of classic MF were excluded. MAIN OUTCOMES AND MEASURES: Main outcomes included clinical and histological characteristics, disease progression, and survival. Prognostic factors were investigated using Cox proportional hazard regression analysis. Distinction between early plaque-stage FMF and advanced plaque-stage FMF was made by a blinded review of skin biopsy specimens from patients presenting with plaques. RESULTS: In a cohort of 147 men and 56 women (median [range] age, 59 [15-93] years), patients with histologically early plaque-stage FMF had a very similar overall survival (OS) rate to patients with only patches and/or follicular papules (10-year OS, 71% vs 80%), while the survival rate of patients with histologically advanced plaque-stage FMF was almost identical to that of patients presenting with tumors (10-year OS, 25% vs 27%). Subsequently, 3 clinical subgroups with significantly different survival data were distinguished: early skin-limited FMF (group A; n = 84; 5-year and 10-year OS, 92% and 72%); advanced skin-limited FMF (group B; n = 102; 5-year and 10-year OS, 55% and 28%); and FMF presenting with extracutaneous disease (group C; n = 17; 5-year and 10-year OS, 23% and 2%). Age at diagnosis, large cell transformation and secondary bacterial infection were independent risk factors for disease progression and/or poor survival. CONCLUSIONS AND RELEVANCE: The results of this study provide useful criteria to differentiate between indolent and aggressive FMF and confirm the existence of a subgroup of FMF with a favorable prognosis.


Assuntos
Neoplasias de Cabeça e Pescoço/patologia , Micose Fungoide/patologia , Couro Cabeludo , Neoplasias Cutâneas/patologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Infecções Bacterianas/complicações , Progressão da Doença , Feminino , Folículo Piloso/patologia , Neoplasias de Cabeça e Pescoço/complicações , Humanos , Masculino , Pessoa de Meia-Idade , Micose Fungoide/complicações , Estadiamento de Neoplasias , Prognóstico , Estudos Prospectivos , Fatores de Risco , Neoplasias Cutâneas/complicações , Taxa de Sobrevida , Adulto Jovem
9.
PLoS One ; 11(2): e0148850, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26872051

RESUMO

BACKGROUND: Light fractionation significantly increases the efficacy of 5-aminolevulinic acid (ALA) based photodynamic therapy (PDT) using the nano-emulsion based gel formulation BF-200. PDT using BF-200 ALA has recently been clinically approved and is under investigation in several phase III trials for the treatment of actinic keratosis. This study is the first to compare BF-200 ALA with ALA in preclinical models. RESULTS: In hairless mouse skin there is no difference in the temporal and spatial distribution of protoporphyrin IX determined by superficial imaging and fluorescence microscopy in frozen sections. In the skin-fold chamber model, BF-200 ALA leads to more PpIX fluorescence at depth in the skin compared to ALA suggesting an enhanced penetration of BF-200 ALA. Light fractionated PDT after BF-200 ALA application results in significantly more visual skin damage following PDT compared to a single illumination. Both ALA formulations show the same visual skin damage, rate of photobleaching and change in vascular volume immediately after PDT. Fluorescence immunohistochemical imaging shows loss of VE-cadherin in the vasculature at day 1 post PDT which is greater after BF-200 ALA compared to ALA and more profound after light fractionation compared to a single illumination. DISCUSSION: The present study illustrates the clinical potential of light fractionated PDT using BF-200 ALA for enhancing PDT efficacy in (pre-) malignant skin conditions such as basal cell carcinoma and vulval intraepithelial neoplasia and its application in other lesion such as cervical intraepithelial neoplasia and oral squamous cell carcinoma where current approaches have limited efficacy.


Assuntos
Ácido Aminolevulínico/análogos & derivados , Fotoquimioterapia/métodos , Fármacos Fotossensibilizantes/farmacologia , Pele/efeitos dos fármacos , Ácido Aminolevulínico/farmacocinética , Ácido Aminolevulínico/farmacologia , Animais , Animais não Endogâmicos , Fracionamento da Dose de Radiação , Avaliação Pré-Clínica de Medicamentos , Células Endoteliais/metabolismo , Feminino , Camundongos , Microscopia de Fluorescência , Fármacos Fotossensibilizantes/farmacocinética , Protoporfirinas/farmacocinética , Pele/irrigação sanguínea , Pele/metabolismo , Sus scrofa
10.
J Cutan Med Surg ; 19(6): 580-7, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25986315

RESUMO

BACKGROUND: For optimal treatment of facial defects following Mohs micrographic surgery (MMS), the aesthetic unit principles should be applied. Often multiple staged procedures and revisions are necessary. OBJECTIVE: To analyze the reconstructive options and outcomes for complex facial defects per aesthetic unit. METHODS: Data of 202 patients, who underwent a facial reconstruction at the department of plastic and reconstructive surgery following MMS, were collected. RESULTS: The central facial units were affected in more than 70%, with over 20% of the defects involving more than 1 unit. Nasal defects required the longest reconstruction time (3-staged forehead flap) and periocular defects the most revisional procedures. In more than 50%, additional operations (range, 1-5) were needed. In 12%, postoperative complications occurred. CONCLUSION: An overview for the reconstructive options of extensive facial skin cancer is presented. Proper treatment requires a structured multidisciplinary approach in order to achieve excellent tumour control and a satisfactory aesthetic and functional end result.


Assuntos
Carcinoma/cirurgia , Neoplasias Faciais/cirurgia , Melanoma/cirurgia , Cirurgia de Mohs , Procedimentos de Cirurgia Plástica , Neoplasias Cutâneas/cirurgia , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma/patologia , Neoplasias Faciais/patologia , Feminino , Humanos , Masculino , Melanoma/patologia , Pessoa de Meia-Idade , Estudos Retrospectivos , Neoplasias Cutâneas/patologia , Retalhos Cirúrgicos , Resultado do Tratamento
12.
Photochem Photobiol ; 90(4): 896-902, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24628584

RESUMO

Different distributions of hexyl aminolevulinate (HAL), aminolevulinic acid (ALA) and methyl aminolevulinate (MAL) in the superficial vasculature are not well studied but they are hypothesized to play an important role in topical photodynamic therapy (PDT). The colocalization of fluorescent CD31 and protoporphyrin IX (PpIX) was calculated using confocal microscopy of mouse skin sections to investigate the vascular distribution after topical application. Vascular damage leads to disruption of the normal endothelial adherens junction complex, of which CD144 is an integral component. Therefore, normal CD31 combined with loss of normal fluorescent CD144 staining was visually scored to assess vascular damage. Both the vascular PpIX concentration and the vascular damage were highest for HAL, then ALA and then MAL. Vascular damage in MAL was not different from normal contralateral control skin. This pattern is consistent with literature data on vasoconstriction after PDT, and with the hypothesis that the vasculature plays a role in light fractionation that increases efficacy for HAL and ALA-PDT but not for MAL. These findings indicate that endothelial cells of superficial blood vessels synthesize biologically relevant PpIX concentrations, leading to vascular damage. Such vascular effects are expected to influence the oxygenation of tissue after PDT which can be important for treatment efficacy.


Assuntos
Ácido Aminolevulínico/análogos & derivados , Ácido Aminolevulínico/farmacologia , Transtornos de Fotossensibilidade/induzido quimicamente , Fármacos Fotossensibilizantes/farmacologia , Pele/efeitos dos fármacos , Administração Tópica , Ácido Aminolevulínico/administração & dosagem , Animais , Antígenos CD , Caderinas , Células Endoteliais/efeitos dos fármacos , Células Endoteliais/efeitos da radiação , Camundongos , Fármacos Fotossensibilizantes/administração & dosagem , Molécula-1 de Adesão Celular Endotelial a Plaquetas/metabolismo , Protoporfirinas/metabolismo
14.
Ned Tijdschr Geneeskd ; 157(12): A5602, 2013.
Artigo em Holandês | MEDLINE | ID: mdl-23515035

RESUMO

The most common skin cancers are basal cell carcinoma (BCC) and squamous cell carcinoma (SCC). Conventional excision is still the current treatment of choice for these malignant tumours. Given the many subtypes and high incidence, the treatment of these skin tumours is not only a matter of surgical procedures. There are many different therapeutic options, from smearing to cutting. Those treating patients with non-melanoma skin cancer should have knowledge of the advantages and disadvantages of these many options. Radical surgical treatment is desired, but large margins are preferably avoided. Mohs micrographic surgery is a treatment option available for BCC and SCC in the face. Superficial BCC can be effectively treated with optimal cosmetic outcome in various, non-invasive ways.


Assuntos
Carcinoma Basocelular/cirurgia , Carcinoma de Células Escamosas/cirurgia , Cirurgia de Mohs , Neoplasias Cutâneas/cirurgia , Procedimentos Cirúrgicos Ambulatórios , Antineoplásicos/uso terapêutico , Carcinoma Basocelular/tratamento farmacológico , Carcinoma de Células Escamosas/tratamento farmacológico , Humanos , Neoplasias Cutâneas/tratamento farmacológico , Resultado do Tratamento
15.
Acta Derm Venereol ; 92(6): 641-7, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22964973

RESUMO

Photodynamic therapy (PDT) using topical porphyrin-precursors is a promising treatment for superficial basal cell carcinoma (sBCC), but it needs further optimization. The aim of this study was to compare 5-year lesion (complete) response rates of sBCC treated with topical aminolaevulinic acid (ALA)-PDT using a single illumination vs. ALA-PDT using a 2-fold illumination scheme. A prospective, randomized study was performed, in which 91 patients with 299 lesions were treated with a 2-fold illumination scheme with 2 light fractions of 20 and 80 J/cm2 delivered 4 and 6 h after a single application of 20% ALA, and 106 patients with 274 lesions were treated with a single illumination of 75 J/cm2 4 h after a single application of 20% ALA. All lesions were treated at a fluence rate of 50 mW/cm2. An interim time to event analysis of complete response (CR) rates at 12 months showed encouraging results, and therefore lesions were followed for 5 years post-therapy. A third group of 50 patients with 172 lesions treated with 2-fold illumination were included after the initial period and analysed separately. The CR rate was significantly greater following the 2-fold illumination than the single illumination (p = 0.0002, log-rank test). Five years after therapy the CR rate after 2-fold illumination was 88%, whereas the CR rate after single illumination was 75%. The CR rate in the third group of lesions, treated with 2-fold illumination was 97% and 88% at 12 months and 5 years after therapy, respectively. Long-term follow-up indicates superior efficacy in sBCC of ALA-PDT with 2-fold illumination compared with ALA-PDT with single illumination.


Assuntos
Ácido Aminolevulínico/uso terapêutico , Carcinoma Basocelular/tratamento farmacológico , Fotoquimioterapia/métodos , Fármacos Fotossensibilizantes/uso terapêutico , Neoplasias Cutâneas/tratamento farmacológico , Administração Cutânea , Adulto , Idoso , Idoso de 80 Anos ou mais , Ácido Aminolevulínico/administração & dosagem , Carcinoma Basocelular/patologia , Feminino , Seguimentos , Humanos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Países Baixos , Fármacos Fotossensibilizantes/administração & dosagem , Estudos Prospectivos , Neoplasias Cutâneas/patologia , Fatores de Tempo , Resultado do Tratamento
16.
Ned Tijdschr Geneeskd ; 155(47): A4110, 2011.
Artigo em Holandês | MEDLINE | ID: mdl-22129810

RESUMO

OBJECTIVE: To calculate the cumulative risks and incidence rates for the development of multiple (two or more) basal cell carcinomas (BCC). DESIGN: A retrospective cohort study with data from PALGA, the nationwide network and registry of histopathology and cytopathology in the Netherlands. METHOD: Using pathology reports, the first 2483 patients diagnosed with a first histologically confirmed BCC in the year 2004 were retrospectively followed for 5 years. The Andersen-Gill survival analysis was used to study whether gender or age affected the risk of developing multiple BCCs. RESULTS: In total, 2483 patients developed 3793 BCCs. The five-year cumulative risk of developing multiple BCCs was 29.2%. The incidence rate for the development of two or more BCCs was 25,318 per 100,000 person-years in the first half year after first BCC diagnosis, decreasing to 6953 per 100,000 person-years after 5 years of follow-up. Compared with women men had a 30% (adjusted HR 1.30; 95% CI 1.11-1.53) higher risk of developing multiple BCCs and those aged 65-79 years had an 80% (adjusted HR 1.81; 95% CI 1.37-2.41) higher risk of having two or more BCCs compared with patients younger than 50 years. CONCLUSION: Almost one third of the patients with a BCC developed two or more BCCs, most frequently in the period shortly after the first BCC. At diagnosis of BCC a full body skin examination should be performed and repeated annually for at least three years.


Assuntos
Carcinoma Basocelular/diagnóstico , Sistema de Registros , Neoplasias Cutâneas/diagnóstico , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma Basocelular/epidemiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Países Baixos/epidemiologia , Estudos Retrospectivos , Risco , Neoplasias Cutâneas/epidemiologia , Análise de Sobrevida
17.
J Biophotonics ; 4(10): 721-30, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21842485

RESUMO

Optically monitoring the vascular physiology during photodynamic therapy (PDT) may help understand patient-specific treatment outcome. However, diffuse optical techniques have failed to observe changes herein, probably by optically sampling too deep. Therefore, we investigated using differential path-length spectroscopy (DPS) to obtain superficial measurements of vascular physiology in actinic keratosis (AK) skin. The AK-specific DPS interrogation depth was chosen up to 400 microns in depth, based on the thickness of AK histology samples. During light fractionated aminolevulinic acid-PDT, reflectance spectra were analyzed to yield quantitative estimates of blood volume and saturation. Blood volume showed significant lesion-specific changes during PDT without a general trend for all lesions and saturation remained high during PDT. This study shows that DPS allows optically monitoring the superficial blood volume and saturation during skin PDT. The patient-specific variability supports the need for dosimetric measurements. In DPS, the lesion-specific optimal interrogation depth can be varied based on lesion thickness.


Assuntos
Tecnologia de Fibra Óptica/métodos , Ceratose Actínica/sangue , Fotoquimioterapia/métodos , Refratometria/métodos , Pele/irrigação sanguínea , Difusão , Humanos , Ceratose Actínica/tratamento farmacológico , Ceratose Actínica/patologia , Pele/metabolismo , Pele/patologia , Resultado do Tratamento
18.
Photochem Photobiol ; 86(5): 1140-6, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20553407

RESUMO

Photodynamic therapy (PDT) for actinic field cancerization is effective but painful. Pain mechanisms remain unclear but fluence rate has been shown to be a critical factor. Lower fluence rates also utilize available oxygen more efficiently. We investigated PDT effect in normal SKH1-HR mice using low and high fluence rate aminolevulinic acid (ALA) PDT and a fractionated illumination scheme. Six groups of six mice with different light treatment parameters were studied. Visual skin damage was assessed up to 7days post-PDT. Fluorescence and reflectance spectroscopy during illuminations provided us with real-time information about protoporphyrin IX (PpIX) photobleaching. A novel dosing approach was introduced in that we used a photobleaching percentage instead of a preset fluence. Data show similar total and maximum damage scores in high and low fluence rate groups. Photobleaching of PpIX in the low fluence rate groups shows a trend toward more efficient photobleaching. Results indicate that low fluence rate PDT is as effective as and more efficient than high fluence rate PDT in normal mouse skin. Low fluence rate PDT light protocols need to be explored in human studies in search for an effective and well-tolerated treatment for actinic field cancerization.


Assuntos
Ácido Aminolevulínico , Fotoquimioterapia , Pele/efeitos da radiação , Animais , Relação Dose-Resposta à Radiação , Feminino , Camundongos , Fármacos Fotossensibilizantes/química , Protoporfirinas/química , Fatores de Tempo
19.
J Drugs Dermatol ; 9(2): 112-6, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-20214171

RESUMO

Skin cancer is the most commonly diagnosed cancer in populations of predominantly Caucasian origins. As the main cause of skin cancer is excessive sun exposure among a sun-sensitive population, most skin cancers are theoretically avoidable, and prevention is an important topic for public health purposes. The development of skin cancer may be limited by effective primary prevention campaigns, causing people to protect themselves from the sun. In order to be effective, the right people need to become aware of the risks and benefits; they also need to be convinced that they can take effective protective measures. Secondary skin cancer prevention aims to avoid skin cancer morbidity and mortality and is, therefore, mainly aimed at early detection of cutaneous melanomas. Around the world, elderly men are the worst off in terms of melanoma mortality statistics and would be an important target group for secondary prevention. Several prevention initiatives have been developed, including awareness campaigns and voluntary skin cancer screening days. So far, few of these initiatives have proven to be successful in changing population behavior and/or skin cancer related mortality. Most of these initiatives appealed more to (young) women rather than the elderly males who would benefit most. In this review, various aspects of primary and secondary skin cancer prevention are discussed, including the results of some of the primary and secondary prevention initiatives.


Assuntos
Educação em Saúde , Neoplasias Cutâneas/prevenção & controle , Adulto , Criança , Feminino , Humanos , Masculino , Programas de Rastreamento , Neoplasias Cutâneas/diagnóstico
20.
Acta Derm Venereol ; 88(6): 547-54, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-19002337

RESUMO

Light fractionation in aminolaevulinic acid photodynamic therapy (PDT) of superficial basal cell carcinoma has been shown to enhance the therapeutic efficacy significantly. We have shown previously that this increase in efficacy is not simply due to an increase in the amount of protoporphyrin utilized during therapy. The present study investigated the spatial distribution of protoporphyrin in 32 superficial basal cell carcinomas undergoing light-fractionated PDT. Superficial fluorescence imaging performed during therapy was compared with the microscopic analysis of protoporphyrin fluorescence in biopsies acquired immediately before the second of two light fractions. The microscopic distribution of fluorescence was also compared with tumour sections immunohistochemically stained for Ki-67. Large variations in superficial and microscopic protoporphyrin fluorescence were found in both control and treated lesions. Despite these variations there was a reasonable correlation between the two techniques (R2=0.86). The mean fluorescence intensity in control biopsies was greater than in illuminated lesions before the second light fraction, but there was no significant difference in the variation within and between regions of interest in each of these sets of lesions. There was no clear trend in depth of protoporphyrin reappearance during the dark interval between light fractions. The general distribution of cells stained positive for Ki-67 followed the protoporphyrin fluorescence that was associated with islands of basal cell carcinoma. In conclusion, this study confirms that the mean relative re-synthesis of protoporphyrin after PDT is consistent with that found previously in pre-clinical models. There are large variations in fluorescence within superficial basal cell carcinoma that include regions of tumour cells that do not synthesize protoporphyrin.


Assuntos
Carcinoma Basocelular/patologia , Fotoquimioterapia , Fármacos Fotossensibilizantes/farmacocinética , Protoporfirinas/farmacocinética , Neoplasias Cutâneas/patologia , Ácido Aminolevulínico/uso terapêutico , Biópsia , Carcinoma Basocelular/tratamento farmacológico , Carcinoma Basocelular/metabolismo , Humanos , Imuno-Histoquímica , Antígeno Ki-67/metabolismo , Microscopia de Fluorescência , Fármacos Fotossensibilizantes/uso terapêutico , Pele/metabolismo , Pele/patologia , Pele/efeitos da radiação , Neoplasias Cutâneas/tratamento farmacológico , Neoplasias Cutâneas/metabolismo
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