Agnieszka Zawislak

Successful photodynamic therapy of vulval Paget's disease using a novel patch‐based delivery system containing 5‐aminolevulinic acid

Case report A 66 year old Caucasian female attended for treatment of vulval Paget’s disease. She had an eight year history of persistent vulval itch, which had been treated unsuccessfully with antifungal, antibiotic and steroid creams. Biopsy at a district hospital revealed groups of large cells with atypical nuclei located within the epidermis with abundant clear to eosinophilic cytoplasm (Fig. 1A). These cells were positive with cytokeratin 7 and negative with cytokeratin 20. A diagnosis of Paget’s disease was made. There was no evidence of dermal invasion by tumour. Mammography, colonoscopy and computed tomography of the abdomen were all negative. Clinical examination showed a 4 3 cm, purple-red, well-demarcated, moist lesion on the left labia majora. Itch was graded on the visual analogue scale (0 to 10) at 8, becoming worse during the night and interrupting her sleep pattern. The patient was reluctant to undergo surgical excision and an experimental treatment using 5-aminolevulinic acid (ALA)-based photodynamic therapy was offered. Informed consent, as part of a trial protocol, was obtained. The treatment comprised part of an ongoing trial using photodynamic therapy for the treatment of a range of vulval lesions. The trial was performed under local Ethical Committee approval. A bioadhesive patch, which was developed in the School of Pharmacy, Queen’s University Belfast, containing 38 mg cm 2 ALA (Crawford Pharmaceuticals, Milton

Response of vulval lichen sclerosus and squamous hyperplasia to photodynamic treatment using sustained topical delivery of aminolevulinic acid from a novel bioadhesive patch system.

This study evaluated the clinical and histopathological responses of vulval lichen sclerosus (LS) and squamous hyperplasia (SH) to photodynamic therapy (PDT). A novel bioadhesive patch containing aminolevulinic acid (ALA) at a dose of (38 mg/cm2) was used to treat 10 patients before irradiation with light of 630 nm. Clinical, histopathological and pathological responses to treatment were assessed at 6 weeks post‐treatment. After 17 cycles of PDT, six patients reported significant symptomatic relief and no cutaneous photosensitivity. Histopathological differences were not demonstrated, but statistically significant induction of apoptosis was seen. It can be concluded that ALA‐PDT patch‐based formulation is pragmatic and primarily offers symptomatic management of vulval LS and SH.

Clinical and immunohistochemical assessment of vulval intraepithelial neoplasia following photodynamic therapy using a novel bioadhesive patch-type system loaded with 5-aminolevulinic acid

BACKGROUND The work in this study appraised photodynamic treatment (PDT) as a treatment method for vulval intraepithelial neoplasia (VIN) using a novel bioadhesive patch to deliver aminolevulinic acid. An analysis of changes in expression of apoptotic and cell cycle proteins (p53, p21, Mdm2, Blc-2, Bax, Ki-67) in response to PDT was evaluated. METHODS PDT was performed using non-laser light, either as a one or two-cycle treatment, with clinical and pathological assessment following after 6 weeks. Twenty-three patients with 25 VIN lesions underwent 49 cycles of PDT. Patches were designed to conform to uneven vulval skin and contained 38 mg cm(-2) aminolevulinic acid. Assessment was carried out at 6 weeks post-treatment. Patient-based treatment assessment, along with clinical and pathological changes, were monitored. Immunohistochemical staining was used to elucidate a possible biomolecular basis for induced cellular changes. RESULTS Most patients (52%) reported a symptomatic response, with normal pathology restored in 38% of lesions. The patch was easy to apply and remove, causing minimal discomfort. Fluorescence inspection confirmed protoporphyrin accumulation. Pain during implementation of PDT was problematic, necessitating some form of local analgesia. Changes in expression of cell cycle and apoptotic-related proteins suggested involvement of apoptotic pathways. Down regulation of p21 and inverse changes in Bcl-2 and Bax were key findings. CONCLUSION Treatment of VIN lesions using a novel bioadhesive patch induced changes in cell cycle and apoptotic proteins in response to PDT with possible utilisation of apoptotic pathways. The efficacy of PDT in treating VIN could be improved by a better understanding of these apoptotic mechanisms, the influence of factors, such as HPV status, and of the need for effective pain management.

Phototoxicity of 5-aminolevulinic acid in the HeLa cell line as an indicative measure of photodynamic effect after topical administration to gynecological lesions of intraepithelial form.

AbstractPurpose. The depth-resolved pattern of aminolevulinic acid (ALA) concentration in excised vaginal tissue was determined after in vitro application of an ALA-loaded bioadhesive patch. From this data, the tissue concentration of ALA achievable at a specified depth from the surface could be related to the concentration needed to elicit a photodynamic effect in a model gynecological tumor cell line (HeLa). Methods. Excised vaginal tissue was mounted in a modified Franz diffusion cell and exposed to a water-soluble, ALA-loaded, bioadhesive patch. After a period of time, the tissue was cryostatically sectioned and the stratal concentration of radiolabeled ALA determined using scintillation spectroscopy. HeLa cells were cultured in media containing specific concentrations of ALA and exposed to standard photodynamic protocols of light exposure. Results. An ALA concentration of 65.6 mM was achievable at 2.375 mm from the tissue surface after application of ALA-loaded patch. The photodynamic effectiveness of this concentration was demonstrated in HeLa with exposure to concentrations exceeding 1.0 mM ALA bringing about reductions in viable cell numbers by 90%. An enhancement of PpIX production using adjunctive EDTA over the clinically relevant 4 h application time interval was shown to be minimal in HeLa. Instead, PpIX production was more closely correlated with ALA concentration, with 100 mM ALA producing approximately 3100 ng PpIX mg-1 protein in the same time period. Conclusions. Given that vaginal intraepithelial neoplasias can extend to 2.0 mm from the lesion surface, the ALA permeability derived from a bioadhesive patch is sufficient to induce photosensitization suitable for light induced destruction at deep sites of this type of lesion.