Biomedical subjects

A M Soler

Publications and source records attributed to A M Soler.

6 recordsLinked to original sources

PubMed2001

Selective distribution of porphyrins in skin thick basal cell carcinoma after topical application of methyl 5-aminolevulinate.

Topical photodynamic therapy (PDT) of superficial basal cell carcinoma (BCC) with 5-aminolevulinic acid (ALA) has achieved promising clinical results. However, the efficacy of this therapy for thick BCC is dramatically decreased by a limited diffusion of hydrophilic ALA into the tumor. Lipophilic esters of ALA may enhance their penetration into the lesion. In this randomized, open clinical study, microscopic fluorescence photometry incorporating a light-sensitive thermo-electrically cooled charge-coupled device (CCD) camera was employed to investigate the penetration of methyl 5-aminolevulinate-induced porphyrin fluorescence in thick BCC lesions. Both the distribution pattern and the amount of porphyrins in 32 lesions of 16 patients were studied after topical application of 16, 80 or 160 mg/g of methyl 5-aminolevulinate for 3 or 18 h. A highly selective and homogeneous distribution of methyl 5-aminolevulinate-induced porphyrin fluorescence was seen in all lesions studied, with much less fluorescence in the adjacent normal skin tissues. In lesions of up to 2 mm thickness the application of 160 mg/g methyl 5-aminolevulinate for 3 h showed the highest ratio of porphyrin fluorescence depth to tumor depth (0.98+/-0.04), thus providing a biologic rationale for a clinical PDT trial with this regimen.

Administration, Topical↗

PubMed2001

A follow-up study of recurrence and cosmesis in completely responding superficial and nodular basal cell carcinomas treated with methyl 5-aminolaevulinate-based photodynamic therapy alone and with prior curettage.

BACKGROUND: Methyl 5-aminolaevulinate (mALA) is an ester derivative of 5-aminolaevulinic acid (ALA) with increased lipophilicity compared with ALA. OBJECTIVES: To assess long-term cure rate, cosmesis, recurrence rate and extent of fibrosis after mALA-based photodynamic therapy (PDT) of superficial and nodular basal cell carcinomas (BCCs) showing early complete response to treatment. METHODS: Of 350 BCCs treated, 310 responded completely. These were in 59 patients who were followed for 2-4 years (mean 35 months) after mALA-PDT. Nodular tumours were curetted before PDT, and mALA 160 mg g(-1) was applied to all tumours for 24 h or 3 h before illumination from a broad-band halogen light source with light doses from 50 to 200 J cm(-2). Fibrosis was assessed histologically in 23 biopsies. RESULTS: The overall cure rate for 350 BCCs, including non-responders and recurrences was 79%. Of 310 lesions, 277 (89%) remained in complete response, and the cosmetic outcome was excellent or good in 272 of the completely responding lesions (98%). Histological examination showed dermal fibrosis in one of 23 biopsies. CONCLUSIONS: We conclude that mALA-based PDT with prior curettage of nodular lesions is a promising new method for the treatment of BCC.

Aged↗

PubMed2000

Photodynamic therapy of residual or recurrent basal cell carcinoma after radiotherapy using topical 5-aminolevulinic acid or methylester aminolevulinic acid.

This study was conducted to assess the efficacy of aminolevulinic acid-based photodynamic treatment for residual or recurrent basal cell carcinomas after radiotherapy. Photodynamic therapy with either topical 5-aminolevulinic acid 20% and dimethylsulfoxide 99% pretreatment or topical methylester aminolevulinic acid 20% w/w in cream and subsequent light illumination of 50-200 J/cm2 was performed after an initial skin shaving procedure in 20 patients with 22 residual or recurrent basal cell carcinomas. Three lesions were treated once, while twelve, three, one and two lesions received two, three, four and five treatment sessions respectively. At examination, 6-40 months (mean 22 months) after the last treatment, 18 lesions were in complete remission. All lesions were considered excellent or good with regard to cosmetic outcome. Three lesions responded only partially to photodynamic therapy and a fourth lesion recurred 21 months after photodynamic treatment. Two of these four lesions were confirmed as the morpheaform type of basal cell carcinoma.

Administration, Topical↗

PubMed2000

Photodynamic therapy of superficial basal cell carcinoma with 5-aminolevulinic acid with dimethylsulfoxide and ethylendiaminetetraacetic acid: a comparison of two light sources.

The aim of this prospective randomized study was to compare the clinical and cosmetic outcome of superficial basal cell carcinomas (BCC), using either laser or broadband halogen light, in photodynamic therapy with topical 5-aminolevulinic acid (ALA). A total of 83 patients with 245 superficial BCC were included in the study. Standard treatment involved 15 min of local pretreatment with 99% dimethylsulfoxide (DMSO) before topical application of 20% ALA with DMSO (2%) and ethylendiaminetetraacetic acid (2%) as cofactors for 3 h before light exposure with either laser or a broadband lamp (BL). A complete response was achieved in 95 lesions (86%) in the laser group and 110 lesions (82%) in the BL group 6 months after treatment. Of these, 80 lesions (84%) in the laser group and 101 lesions (92%) in the lamp group were independently evaluated to have an excellent or good cosmetic post-treatment score. No serious adverse events were reported. This study shows that there is no statistical significant difference in cure the rate (P = 0.49) and the cosmetic outcome (P = 0.075) with topical application of a modified ALA-cream between light exposure from a simple BL with continuous spectrum (570-740 nm) or from a red-light laser (monochromatic 630 nm). Cost and safety are further elements in favor of the BL in this setting.

Aminolevulinic Acid↗

PubMed1999

Photodynamic therapy by topical aminolevulinic acid, dimethylsulphoxide and curettage in nodular basal cell carcinoma: a one-year follow-up study.

Fifty-eight patients with 119 nodular (2 mm or more in thickness) basal cell carcinomas successfully treated with photodynamic therapy were included in this 1-year follow-up study. The initial cure rate at 3-6 months was 92% after photodynamic therapy, which included an initial debulking procedure and topical application of dimethylsulphoxide in order to enhance penetration of 5-aminolevulinic acid (20% in cream) to which the lesions were exposed for 3 h prior to exposure to light. At examination 12-26 months (mean 17 months) after treatment 113 lesions (95%) were still in complete response. Six lesions (5%) had recurred, located on the face, scalp and ear. The cosmetic outcome was evaluated as excellent to good in 91%. Microscopic examination of biopsies taken from healed areas in 7 patients did not reveal any sign of damage in 5 and only minor alterations in 2.

Administration, Topical↗

PubMed1989

Anaerobic threshold estimation by statistical modelling.

Anaerobic threshold (AT) is usually estimated as a change point problem by visual analysis of the cardiorespiratory response to incremental dynamic exercise. In this study, two phase linear (TPL) models of the linear-linear and linear-quadratic type were used for the estimation of AT. The correlation coefficient between the classical and statistical approaches was 0.88, and 0.89 after outlier exclusion. The TPL models provide a simple method for estimating AT that can be easily implemented using a digital computer for the automatic pattern recognition of AT.

Anaerobic Threshold↗