Hexyl aminolevulinate, 5-aminolevulinic acid nanoemulsion and methyl aminolevulinate in photodynamic therapy of non-aggressive basal cell carcinomas: A non-sponsored, randomized, prospective and double-blinded trial

BACKGROUND

In the photodynamic therapy (PDT) of non-aggressive basal cell carcinomas (BCCs), 5-aminolevulinic acid nanoemulsion (BF-200ALA) has shown non-inferior efficacy when compared with methyl aminolevulinate (MAL), a widely used photosensitizer. Hexyl aminolevulinate (HAL) is an interesting alternative photosensitizer. To our knowledge, this is the first study using HAL-PDT in the treatment of BCCs.

OBJECTIVES

To compare the histological clearance, tolerability (pain and post-treatment reaction) and cosmetic outcome of MAL, BF-200 ALA and low-concentration HAL in the PDT of non-aggressive BCCs.

METHODS

Ninety-eight histologically verified non-aggressive BCCs met the inclusion criteria, and 54 patients with 95 lesions completed the study. The lesions were randomized to receive LED-PDT in two repeated treatments with MAL, BF-200 ALA or HAL. Efficacy was assessed both clinically and confirmed histologically at three months by blinded observers. Furthermore, cosmetic outcome, pain, post-treatment reactions fluorescence and photobleaching were evaluated.

RESULTS

According to intention-to-treat analyses, the histologically confirmed lesion clearance was 93.8% (95% confidence interval [CI] = 79.9-98.3) for MAL, 90.9% (95% CI = 76.4-96.9) for BF-200 ALA and 87.9% (95% CI = 72.7-95.2) for HAL, with no differences between the arms (P = 0.84). There were no differences between the arms as regards pain, post-treatment reactions or cosmetic outcome.

CONCLUSIONS

Photodynamic therapy with low-concentration HAL and BF-200 ALA has a similar efficacy, tolerability and cosmetic outcome compared to MAL. HAL is an interesting new option in dermatological PDT, since good efficacy is achieved with a low concentration.

Ablative fractional laser-assisted photodynamic therapy for lentigo maligna: a prospective pilot study

BACKGROUND

Lentigo maligna (LM) is an in situ form of melanoma carrying a risk of progression to invasive lentigo maligna melanoma (LMM). LM poses a clinical challenge, with subclinical extension and high recurrence rates after incomplete surgery. Alternative treatment methods have been investigated with varying results. Photodynamic therapy (PDT) with methylaminolaevulinate (MAL) has already proved promising in this respect.

OBJECTIVES

To investigate the efficacy of ablative fractional laser (AFL)-assisted PDT with 5-aminolaevulinic acid nanoemulsion (BF-200 ALA) for treating LM.

METHODS

In this non-sponsored prospective pilot study, ten histologically verified LMs were treated with AFL-assisted PDT three times at 2-week intervals using a light dose of 90 J/cm² per treatment session. Local anaesthesia with ropivacaine was used. Four weeks after the last PDT treatment the lesions were treated surgically with a wide excision and sent for histopathological examination. The primary outcome was complete histopathological clearance of the LM from the surgical specimen. Patient-reported pain during illumination and the severity of the skin reaction after the PDT treatments were monitored as secondary outcomes.

RESULTS

The complete histopathological clearance rate was 7 out of 10 LMs (70%). The pain during illumination was tolerable, with the mean pain scores for the PDT sessions on a visual assessment scale ranging from 2.9 to 3.8. Some severe skin reactions occurred during the treatment period, however.

CONCLUSIONS

Ablative fractional laser-assisted PDT showed moderate efficacy in terms of histological clearance. It could constitute an alternative treatment for LM but due to the side effects it should only be considered in inoperable cases.

Hyperspectral imaging system in the delineation of Ill-defined basal cell carcinomas: a pilot study

BACKGROUND

Basal cell carcinoma (BCC) is the most common skin cancer in the Caucasian population. Eighty per cent of BCCs are located on the head and neck area. Clinically ill-defined BCCs often represent histologically aggressive subtypes, and they can have subtle subclinical extensions leading to recurrence and the need for re-excisions.

OBJECTIVES

The aim of this pilot study was to test the feasibility of a hyperspectral imaging system (HIS) in vivo in delineating the preoperatively lateral margins of ill-defined BCCs on the head and neck area.

METHODS

Ill-defined BCCs were assessed clinically with a dermatoscope, photographed and imaged with HIS. This was followed by surgical procedures where the BCCs were excised at the clinical border and the marginal strip separately. HIS, with a 12-cm² field of view and fast data processing, records a hyperspectral graph for every pixel in the imaged area, thus creating a data cube. With automated computational modelling, the spectral data are converted into localization maps showing the tumour borders. Interpretation of these maps was compared to the histologically verified tumour borders.

RESULTS

Sixteen BCCs were included. Of these cases, 10 of 16 were the aggressive subtype of BCC and 6 of 16 were nodular, superficial or a mixed type. HIS delineated the lesions more accurately in 12 of 16 of the BCCs compared to the clinical evaluation (4 of 16 wider and 8 of 16 smaller by HIS). In 2 of 16 cases, the HIS-delineated lesion was wider without histopathological confirmation. In 2 of 16 cases, HIS did not detect the histopathologically confirmed subclinical extension.

CONCLUSIONS

HIS has the potential to be an easy and fast aid in the preoperative delineation of ill-defined BCCs, but further adjustment and larger studies are warranted for an optimal outcome.

UAS BASED TREE SPECIES IDENTIFICATION USING THE NOVEL FPI BASED HYPERSPECTRAL CAMERAS IN VISIBLE, NIR AND SWIR SPECTRAL RANGES

Unmanned airborne systems (UAS) based remote sensing offers flexible tool for environmental monitoring. Novel lightweight Fabry-Perot interferometer (FPI) based, frame format, hyperspectral imaging in the spectral range from 400 to 1600 nm was used for identifying different species of trees in a forest area. To the best of the authors’ knowledge, this was the first research where stereoscopic, hyperspectral VIS, NIR, SWIR data is collected for tree species identification using UAS. The first results of the analysis based on fusion of two FPI-based hyperspectral imagers and RGB camera showed that the novel FPI hyperspectral technology provided accurate geometric, radiometric and spectral information in a forested scene and is operational for environmental remote sensing applications.

Fur animal botulism hazard due to feed

To assess the botulism hazard in fur animal feed production, 236 fur animal feed components and feed samples were analysed for Clostridium botulinum by detecting BoNT-encoding genes (botA, botB, botC, botE or botF) by PCR and for sulphite-reducing clostridia (SRC) by iron sulphite agar. The quality of the hazard analysis of critical control points (HACCP) -based in-house control system (IHCS) was evaluated with respect to botulism risk in feed plants (n=32). The overall prevalence of C. botulinum was 13% in different feed components and 5% in feed. The estimated MPN count of C. botulinum in feed components was 6.4 × 10(3)/kg at the highest and was shown to poorly correlate with SRC count. The critical control points in IHCSs were variable, and control limits were improperly set in most feed-producing plants. C. botulinum possesses a persistent safety hazard for fur animals by feed production, and control practices should be reassessed.