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Notes: Summary  Topical 5-aminolaevulinic acid (ALA) photodynamic therapy (PDT) is used increasingly for superficial non-melanoma skin cancer (NMSC) and dysplasia. However, the relative accumulation of the photosensitizer protoporphyrin IX (PpIX) in diseased tissue is not specific for neoplastic disease, and has been shown after the application of ALA to benign proliferative skin conditions such as viral warts and psoriasis. This review appraises the quality of evidence available for the use of topical ALA–PDT in the treatment of skin conditions other than NMSC. The diseases that have been studied in most detail are recalcitrant viral warts, acne, psoriasis and cutaneous T-cell lymphoma. Publications relating to the treatment of other diseases by topical PDT are restricted to small case series or case reports. The relevant literature will be discussed and the potential for topical PDT in the treatment of several skin diseases is highlighted, although more detailed studies are required to clarify the role of PDT beyond the treatment of NMSC.

Notes: Background  We recently investigated the characteristics of psoralen plus ultraviolet (UV) A erythema in skin photosensitized by topical 8-methoxypsoralen (8-MOP) in three independent studies.Objectives  In order to determine the optimal time to read the minimal phototoxic dose (MPD) after treatment with topical 8-MOP and irradiation with UVA, we assessed the overall data.Methods  One forearm of each subject was immersed in 8-MOP solution for 15 min and test sites on the flexor surface of the forearm were immediately exposed to a UVA dose series. Erythema was assessed visually and objectively using a reflectance instrument at 24-h intervals for 7 days.Results  Results were obtained from 44 subjects (predominantly Fitzpatrick skin phototype II). A broad erythemal plateau was evident beyond 72 h and the visual MPD was significantly lower at 96, 120 and 144 h than at 72 h (P 〈 0·01). Only 30% of subjects were at peak erythema at the conventional MPD assessment time of 72 h. The median time to reach maximal erythema was 96 h (range 48–144). Objectively, 85% of subjects were at peak erythema at or beyond 96 h.Conclusions  We recommend that (i) the optimal time to read the topical 8-MOP MPD is 4 days after UVA exposure as readings beyond this time may be difficult to interpret because of the development of pigmentation, and (ii) 40% of the topical 8-MOP MPD should be considered for the first treatment.

Notes: Background  Fluoroquinolone antibiotics (FQs) are associated with phototoxic skin reactions following exposure to sunlight.Objectives  We aimed to compare the phototoxic potential of sitafloxacin, a novel FQ with three others: sparfloxacin, enoxacin, levofloxacin and placebo in Caucasian volunteers. In a second study, two dosage regimens of sitafloxacin were compared with placebo in Oriental subjects.Methods  Randomized, placebo-controlled, assessor-blinded clinical trial. In 40 healthy Caucasians, sitafloxacin 100 mg twice a day (n = 8), sparfloxacin 200 mg day−1 (n = 8), enoxacin 200 mg three times a day (n = 8), levofloxacin 100 mg three times a day (n = 8) and placebo (n = 8) were given in oral doses for 6 days. In the second study, sitafloxacin 50 mg and 100 mg, both twice daily, were compared with placebo in 17 healthy Oriental subjects. Using an established monochromator technique, baseline threshold erythema levels were established pre-drug and on-drug. The phototoxic index (PI) baseline, minimal erythema dose (MED) divided by on-drug MED for each medication at each wavelength was determined and related to sitafloxacin peak plasma levels. The duration of susceptibility to phototoxicity was assessed by repeat phototesting daily after stopping medication.Results  In the Caucasian study, sitafloxacin 100 mg twice a day produced mild ultraviolet (UV) A-dependent phototoxicity (median PI = 1·45) at 365 ± 30 nm (half-maximum bandwidth), maximal at 24 h with normalization by 24 h postdrug cessation. The sparfloxacin group experienced severe phototoxicity maximal at 24 h and, unusually for an FQ, extended in the visible region (430 ± 30 nm), maximal at 400 ± 30 nm (median PI = 12·35) with abnormal pigmentation at on-drug phototest sites lasting, although fading, for up to 1 year. Enoxacin showed UVA-dependent phototoxicity (335–365 ± 30 nm) median PI 3·94 (at 365 ± 30 nm) returning to normal 48 h after stopping the drug. Fading pigmentation at phototoxic sites also lasted up to 1 year. Phototoxicity was not detected in the levofloxacin or placebo groups. In the Oriental study, no clinically relevant phototoxicity was seen with either sitafloxacin or placebo groups.Conclusions  We conclude that 100 mg twice a day sitafloxacin in Caucasians is associated with a mild degree of cutaneous phototoxicity. Enoxacin 200 mg three times a day and sparfloxacin 200 mg day−1 are much more photoactive. Sparfloxacin phototoxicity is induced by UVA and visible wavelengths. Levofloxacin and placebo failed to show a phototoxic effect. In the Oriental study, sitafloxacin 50 mg twice a day and 100 mg twice a day failed to demonstrate a clinically significant phototoxic effect.

Notes: Summary These guidelines for use of narrowband (TL-01) ultraviolet B have been prepared for dermatologists by the British Photodermatology Group on behalf of the British Association of Dermatologists. They present evidence-based guidance for treatment of patients with a variety of dermatoses and photodermatoses, with identification of the strength of evidence available at the time of preparation of the guidelines, and a brief overview of background photobiology.

Notes: Summary Background  In 1991, consensus guidelines recommended psoralen plus ultraviolet A photochemotherapy (PUVA) for those requiring second-line therapy for psoriasis. Narrowband (TL-01) UVB has since become more widely available, replacing the less effective broadband sources. Objectives To compare the efficacy of TL-01 UVB phototherapy and trimethoxypsoralen (TMP) bath-PUVA for chronic plaque psoriasis. Participants and methods A randomized, observer-masked, intraindividually controlled, paired (half-body) study was done in the Photo(chemo)therapy Unit in Ninewells Hospital and Medical School, Dundee. The study comprised 28 patients (skin phototypes I–III) with chronic plaque psoriasis. Each patient's body halves (sagittal plane) were treated independently, one-half with TL-01 UVB, the other with bath-PUVA. Both treatments were administered according to standard, optimized regimens. Treatment was continued until clearance or minimal residual activity (MRA), or a maximum of 30 treatments. The main outcome measures were treatments and time to clearance/MRA, the proportion reaching clearance/MRA, change in psoriasis severity score (scaling, erythema and induration) and remission durations. Results Of 18 who completed the study, all reached clearance/MRA with TL-01, but three were still not clear after 30 PUVA exposures. TL-01 achieved clearance/MRA a median of 11 (6·5–25; P = 0·001) days more quickly than PUVA, but required a median of 24·5 compared with 19 exposures [95% confidence interval (CI) for difference 1·5–5·5; P = 0·01]. Ten patients were withdrawn (four because of inadequate response of PUVA-treated halves). Analysed on an intention-to-treat basis, 21 of 28 (75%) of all participants reached clearance/MRA with TL-01 compared with 15 of 28 (54%) with PUVA (95% CI for difference 4–37%; P = 0·03). Remission durations did not differ. Conclusions When administered according to these regimens in a skin phototype I–III population, TL-01 UVB is more efficacious than TMP bath-PUVA in the treatment of chronic plaque psoriasis.

Notes: Background  Lentigo maligna (LM) is an in situ form of malignant melanoma, and surgical excision is often unsatisfactory. Imiquimod cream is an immune response modifier and induces a predominantly T-helper 1 type response.Objectives  Assessment of histological and clinical response of surgically resectable LM after treatment with 5% imiquimod cream.Methods  Six patients with LM were treated with 5% imiquimod cream daily for 6 weeks. The whole site of the original lesion was then excised. Clinical and histological and appearances were measured using clinical response and histological grading scores.Results  Complete or almost complete clearance of pigmentation with minimal residual histological evidence of LM was observed in four patients, one patient showed no clinical or histological improvement, and the remaining patient had almost no residual pigmentation clinically after treatment yet histopathological changes remained as severe as before treatment.Conclusions  Topical imiquimod cream merits further investigation as a new therapy for LM.

Notes: Background  Many patients find topical 5-aminolaevulinic acid (ALA) photodynamic therapy (PDT) painful. Local anaesthetics are not routinely used and their effect on PDT pain has not been examined.Objectives  To evaluate the efficacy of tetracaine gel (Ametop®) for pain relief during and after PDT.Methods  A prospective, double-blind, placebo-controlled study of 42 patients with lesions (≤ 2 cm diameter) of superficial nonmelanoma skin cancer or dysplasia. Patients were randomized to either tetracaine (4% w/w) (n = 22) or vehicle (n = 20) gel under occlusion for 1 h pre-irradiation. Pain was assessed during and after irradiation using a visual analogue scale (VAS) and faces pain scale.Results  Patients who received tetracaine gel experienced only slightly less pain during PDT (median VAS 4) compared with those who received placebo (median VAS 4·5) (95% confidence interval for difference 0–3, P = 0·08). No significant difference in pain was experienced between the treatment groups immediately after irradiation or later.Conclusions  When compared with placebo, tetracaine gel did not significantly reduce pain during or after PDT for small lesions of superficial basal cell carcinoma, Bowen's disease or actinic keratosis.

Notes: Summary Background The optimum treatment frequency for narrowband (TL-01) ultraviolet B (NB-UVB) in psoriasis is not yet known. We have previously found three times weekly to be preferable to five times weekly treatment in our population. Objectives To compare twice weekly with three times weekly NB-UVB phototherapy in chronic plaque psoriasis. Methods In an observer-blinded, randomized comparison, patients with chronic plaque psoriasis referred from dermatology out-patient clinics in Tayside for NB-UVB phototherapy received either twice weekly (Monday and Friday) or three times weekly (Monday, Wednesday and Friday) whole-body NB-UVB phototherapy following our standard departmental treatment protocol. Treatment was continued to clearance or until the fourth treatment after minimal residual activity (MRA) was first documented. Number of days in treatment, number of treatments, total dose and time to relapse were recorded. Results In total, 113 patients were recruited, skin phototypes I–III: 58 in the twice weekly and 55 in the three times weekly group. Forty patients in the twice weekly group reached clearance/MRA, as did 44 in the three times weekly group. It took 1·5 (95% confidence interval 1·3–1·7) times longer to reach clearance/MRA with twice weekly therapy, a geometric mean of 88 vs. 58 days (P 〈 0·0001). Small differences in numbers of treatments and total dose to reach clearance tended to favour three times weekly therapy, but these were not significant. Conclusions Three times weekly NB-UVB clears psoriasis significantly faster than twice weekly treatment, and therefore is preferable for most patients.

Notes: A group of interested European Contact Dermatologists/Photobiologists met to produce a consensus statement on methodology, test materials and interpretation of photopatch testing. While it is recognized that a range of local variables operate throughout Europe, the underlying purpose of the work is to act as an essential preamble to a Pan European Photopatch Test Study focusing particularly on sunscreen chemicals.