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How we treat Bowen's disease with topical photodynamic therapy in Dundee
Photodiagnosis and Photodynamic Therapy (2009) 6, 41—45
available at www.sciencedirect.com
journal homepage: www.elsevier.com/locate/pdpdt
How we treat Bowen’s disease with topical photodynamic therapy in Dundee Sasi Kiran Attili, Sally H. Ibbotson MD, FRCP ∗ Photobiology Unit, Ninewells Hospital & Medical School, Dundee, University of Dundee, Dundee DD1 9SY, United Kingdom
KEYWORDS Photodynamic therapy; Bowen’s disease; 5-Aminolaevulinic acid (ALA); Methyl ester ALA (MAL)
Summary We have more than 10 years experience in the Photobiology Unit, in the use of topical photodynamic therapy (PDT) for non-melanoma skin cancer and other skin diseases. During this time we have undertaken approximately 5000 treatments and this article details the practical aspects of how we treat Bowen’s disease with topical PDT. © 2009 Elsevier B.V. All rights reserved.
Introduction Bowen’s disease (BD), or squamous cell carcinoma in situ, usually presents as a well-defined erythematous plaque on photoexposed sites. Lesions are common on the head and neck and lower limbs, although any site can be involved. A delay in diagnosis is often encountered because the lesion is asymptomatic; early skin changes may be subtle and the clinical features overlap with those seen in many benign conditions such as tinea corporis, discoid eczema, and psoriasis. Histological confirmation might therefore be necessary when clinical differentiation between these diseases is difficult. Several equally efficacious (1-year clearance rates 70—100%) non-surgical treatment options are available for the treatment of BD including topical cryotherapy, 5fluorouracil, imiquimod and photodynamic therapy (PDT) [1]. The distinct advantage of PDT is that it selectively targets tumour cells, leaving the surrounding healthy cells
∗ Corresponding author. Tel.: +44 1382 496227; fax: +44 1382 633925. E-mail address: [email protected] (S.H. Ibbotson).
relatively unaffected; thus causing minimal scarring and a much better cosmetic outcome [2]. The Photobiology Unit in Dundee has undertaken approximately 5000 treatments with topical PDT and has over 10 years of experience in its use for a variety of skin diseases. The Unit is part of the Scottish Photodynamic Therapy Centre, established in 2001, which offers topical and systemic PDT for a diverse range of different cancers, including those of lung, brain and gastrointestinal tract and some non-oncological diseases [3,4]. The dermatology PDT team includes two Consultant Dermatologists, a Consultant Photophysicist, Clinical Scientist, Clinical Nurse Co-ordinator, six photobiology technicians and a specialist dermatology registrar. All treatments are under the supervision of the Lead Consultant Dermatologist and technician-led PDT is carried out on a daily basis, in addition to a weekly clinic run by a specialist registrar who sees new and return patients (SA). Referrals are received from dermatologists in our own department, from other regional dermatology centres in Scotland and from local plastic surgeons and oncologists and all referral letters are screened by the consultant dermatologist in charge of the PDT service (SI). In the following section we shall elaborate in a step-wise fashion, on how we treat BD with topical PDT (Fig. 1).
1572-1000/$ — see front matter © 2009 Elsevier B.V. All rights reserved. doi:10.1016/j.pdpdt.2009.04.001
42
S.K. Attili, S.H. Ibbotson
Figure 1
Step-wise illustration of treatment of BD on the leg with PDT.
Selection of patients Patients attending our outpatient clinics are referred for PDT based on clinical and/or histological diagnosis. The choice of therapy (i.e. PDT vs. alternatives) depends on patient suitability and location/number of lesions. PDT is ideally suited for treatment of large/multiple lesions especially on the lower legs, where ulceration, poor healing and
sub-optimal cosmesis from conventional therapies are particular risks.
Consent Once referred, patients are sent information on PDT along with their appointment for the clinic. We take a history regarding current or previous treatments and relative con-
How we treat Bowen’s disease with topical photodynamic therapy traindications to PDT, such as photosensitivity. We assess the lesion, explain the procedure and obtain written consent for treatment. Patients are specifically questioned about factors which may make them susceptible to poor healing or excess bleeding or less likely to respond well to treatment—– such as peripheral vascular disease, diabetes, anticoagulant therapy or immunosuppression. Patients at risk of poor healing on lower leg sites have ankle-brachial-pressure indices measured and are fitted with compression stockings, pretreatment. All lesions are photographed pre-treatment and mapped on a ‘body-site’ chart. The site and maximum lesion diameter is documented.
Surface preparation Patients are instructed (in the written information sent out with the appointment) to apply vaseline to the lesions for 3 days prior to their PDT clinic appointment, in order to soften the surface crust. Lesions are gently abraded (without local anaesthesia) using a spatula or disposable curette (Stiefel 7 mm), so that the surface crust is removed (Fig. 1a—c). This is supposed to facilitate better absorption of the photosensitising agent-usually Metvix creamTM (Galderma, UK) or 5-aminolaevulinic acid (Manmed Pharmaceuticals, UK). However in a recent small comparative study where each half of 16 lesions (superficial BCC or BD) was randomly assigned to surface preparation (gentle curettage or abrasion with a scalpel) or none and then treated with ALA-PDT; there was no significant difference in the response of lesions based on whether surface preparation was performed or not [5].
Application of photosensitiser MetvixTM is the only drug preparation licensed for use in PDT in the UK. Using a spatula a 1 mm thick layer of MetvixTM (160 mg/g (16%) of methyl aminolevulinate as hydrochloride, Galderma, UK) is applied to the lesion as well as to 5 mm of surrounding normal skin (Fig. 1d—f). The cream is secured with TegadermTM and an occlusive dressing (MeporeTM ) is applied for 3 h, to prevent premature initiation of the PDT effect by natural sunlight (Fig. 1g—i). Patients are allowed to wander around freely during this time, but are instructed to stay away from direct sunlight. We do also use 5-aminolaevulinic acid (5-ALA, 20% (w/v) in oil in water base, Manmed Pharmaceuticals, UK) on a named-patient basis, as an alternative and this is usually applied for 4 h for BD.
Fluorescence with Wood’s light At the end of 3 h (or 4 h for 5-ALA) dressings and excess cream are removed (Fig. 1j—l). Visual fluorescence of the lesion is assessed in a dark room, using Wood’s lamp, graded on a 3-point scale for intensity and specificity and recorded [6]. This combination of the lesion margin visible to the naked eye and the margin defined by fluorescence is used to define the irradiation field, which is demarcated to include a 5 mm rim of clinically normal appearing tissue, and the maximum diameter of the field is documented (Fig. 1m—n). In
43
research and other special circumstances we use an optical biopsy or CCD system to quantitatively assess PpIX fluorescence and map the lesion [7,8].
Local anaesthesia We aim to treat patients without using local anaesthesia as it is otherwise a non-invasive procedure. However, all patients are routinely offered cool air treatment (Cynosure® ) during irradiation, which we feel is of considerable benefit. Topical anaesthetic preparations such as tetracaine (AmetopTM ) have not been shown to have a marked or significant effect on pain relief for PDT for small lesions [9]. However, anecdotally we find AmetopTM may alleviate PDT induced pain partially, when used on large areas such as for treatment of actinic damage on the scalp or lower legs. This may of course be a placebo effect, but in these situations or for patients known to have found PDT to be very painful previously, we do apply AmetopTM for 1 h prior to irradiation, although this requires further study. Occasionally some patients with localised disease might need local anaesthetic (1—2% lignocaine without adrenaline) infiltration [10].
Irradiation Irradiation is performed using one of several light sources available in the department [10]. Regular calibration and dosimetry are performed in-house. The light sources we commonly use are the Aktilite® LED sources. We also use, on a named-patient basis, low irradiance, LED light sources which have been shown to be associated with less pain; and moreover have the potential for ambulatory PDT [11,12]. The light source used and the skin surface irradiance is documented and the duration of time required to deliver a standard dose of 125 J/cm2 for laser and non-LED sources or 37 J/cm2 (75 J/cm2 if using 5-ALA; as our clinical experience suggests that 37 J/cm2 may result in lower clearance rates) for the LED’s is also documented (Fig. 1o—q). Immediately post-irradiation, erythema, oedema and urticaria are noted (Fig. 1r) and pain assessed [13,14]. The treatment cycle as above is repeated at 1 week.
Post-treatment care Lesions are covered with MeporeTM for 24 h following PDT and patients are advised to avoid bright sunlight or intense artificial light exposure to the area for up to 48 h after treatment. They are also advised to expect inflammation and crusting at the site over the ensuing 7—10 days and of the potential risk of infection, pigmentary change and scarring.
Assessment of response All patients are asked to routinely score pain on a visual analogue scale immediately after treatment. Clinical clearance is assessed routinely at 3 months and 1 year after last treatment. All lesions are photographed on review. All patients with partial response at 3-month review are offered two further treatments with PDT (1 week apart) and again followed
44
S.K. Attili, S.H. Ibbotson
Figure 2 Bowen’s disease-left lower eyelid. (a) Before and (b) 1 year following 1× PDT cycle showing residual erythema only with clinical clearance of lesion.
up to 1 year following last treatment. Generally we consider incomplete clearance following four PDT treatments to be a PDT failure; as in our experience, the vast majority of patients who clear, do so within two treatment cycles. Patients would be referred for alternative treatments in this situation. Recurrent disease can be retreated by PDT and this is an advantage of PDT and particularly applicable to large or multiple areas and field change.
Discussion The most common side effect experienced with PDT is pain, with up to 20% of patients describing pain as being ‘severe’ [10]. This can sometimes persist for a few hours after treatment, but is usually maximal during the early part of irradiation. Post-inflammatory hyper or hypopigmentation can also occur. Persistent erythema is often
Figure 3
seen at 3 months but does not necessarily indicate residual disease, but can make assessment of response difficult, at this early time point. We look for any residual surface scale on palpation, which is more likely to indicate residual disease. Field change Bowenoid actinic keratoses are often difficult to treat with most modalities, but we have used PDT with success in this situation. However recurrence of BD within the treated site is common, because of the nature of field change dysplasia. PDT can also be used for treatment of BD in specific sites such as around the eyes and genitals. We have recently presented a case series on the treatment of periocular tumours (including BD) with PDT [15] (Fig. 2). PDT seems to have a distinct advantage of superior tolerance compared to imiquimod for these cases, but this needs to be confirmed in larger studies. In our experience treatment of genital lesions with PDT can also be successful, although local anaesthesia is more likely to be required. Acral BD is
Bowen’s disease-left little finger. (a) Before and (b) 1 year following 1× PDT cycle, showing complete clearance.
How we treat Bowen’s disease with topical photodynamic therapy anecdotally supposed to respond poorly with PDT, however we have had a few successes (Fig. 3). The main limiting factors for PDT at the moment are pain and the inconvenience of hospital attendance. Lowirradiance PDT [11,12] however is quite promising and could be the potential alternative, especially for elderly patients who find the need for hospital attendance limiting. In our experience PDT is the treatment of choice for BD on the lower legs and is ideal for large and multiple lesions; or for patients where other modalities of treatment (surgical or non-surgical) are inappropriate or have failed.
References [1] Morton CA, McKenna KE, Rhodes LE. Guidelines for topical photodynamic therapy: update. British Association of Dermatologists Therapy Guidelines and Audit Subcommittee and the British Photodermatology Group. Br J Dermatol 2008;159(December (6)):1245—66. [2] Morton C, Horn M, Leman J, et al. Comparison of topical methyl aminolevulinate photodynamic therapy with cryotherapy or Fluorouracil for treatment of squamous cell carcinoma in situ: results of a multicenter randomized trial. Arch Dermatol 2006;142(June (6)):729—35. [3] Ibbotson SH, Moseley H, Brancaleon L, et al. Photodynamic therapy in dermatology: Dundee clinical and research experience. Photodiagn Photodyn Ther 2004;1:211—23. [4] Moseley H, Ibbotson S, Woods J, et al. Clinical and research applications of photodynamic therapy in dermatology: experience of the Scottish PDT Centre. Lasers Surg Med 2006;38(June (5)):403—16. [5] Moseley H, Brancaleon L, Lesar AE, et al. Does surface preparation alter ALA uptake in superficial non-melanoma skin cancer in vivo? Photodermatol Photoimmunol Photomed 2008;24:72—5.
45
[6] Ibbotson SH. How we treat a superficial basal cell carcinoma with topical photodynamic therapy in Dundee. Photodiag Photodyn Therapy 2006;3:128—31. [7] Hewett J, Nadeau V, Ferguson J, et al. The application of a compact multispectral imaging system with integrated excitation source to in vivo monitoring of fluorescence during topical photodynamic therapy of superficial skin cancers. Photochem Photobiol 2001;73(3):278—82. [8] Ibbotson SH, Jong C, Lesar A, et al. Characteristics of 5aminolaevulinic acid-induced protoporphyrin IX fluorescence in human skin in vivo. Photodermatol Photoimmunol Photomed 2006;22(April (2)):105—10. [9] Holmes MV, Dawe RS, Ferguson J, Ibbotson SH. A randomised, double-blind, placebo-controlled study of the efficacy of tetracaine gel (Ametop) for pain relief during topical photodynamic therapy. Br J Dermatol 2004;150:337—40. [10] Clark C, Bryden AM, Dawe RS, Moseley H, Ferguson J, Ibbotson SH. Topical 5-aminolaevulinic acid photodynamic therapy for cutaneous lesions: outcome and comparison of light sources. Photoderm Photoimmunol Photomed 2003;19:134—41. [11] Moseley H, Allen JW, Ibbotson S, et al. Ambulatory photodynamic therapy: a new concept in delivering photodynamic therapy. Br J Dermatol 2006;154:747—50. [12] Attili SK, Lesar A, McNeill A, et al. An open pilot study of ambulatory photodynamic therapy (PDT) using a wearable lowirradiance organic LED light source in the treatment of non melanoma skin cancer. Br J Dermatol; in press. [13] Clark C, Dawe RS, Moseley H, Ferguson J, Ibbotson SH. The characteristics of erythema induced by topical 5aminolaevulinic acid photodynamic therapy. Photodermatol Photoimmunol Photomed 2004;20(2):105—7. [14] Kerr AC, Ferguson J, Ibbotson SH. Acute phototoxicity with urticarial features during topical 5-aminolaevulinic acid. photodynamic therapy. Clin Exp Dermatol 2007;32(2):201—2. [15] Attili SK, Murgatroyd H, Ibbotson SH, Fleming CJ. Role of non-surgical therapies in the management of periocular malignancy: a case series. EADV 2008 (abstract).
available at www.sciencedirect.com
journal homepage: www.elsevier.com/locate/pdpdt
How we treat Bowen’s disease with topical photodynamic therapy in Dundee Sasi Kiran Attili, Sally H. Ibbotson MD, FRCP ∗ Photobiology Unit, Ninewells Hospital & Medical School, Dundee, University of Dundee, Dundee DD1 9SY, United Kingdom
KEYWORDS Photodynamic therapy; Bowen’s disease; 5-Aminolaevulinic acid (ALA); Methyl ester ALA (MAL)
Summary We have more than 10 years experience in the Photobiology Unit, in the use of topical photodynamic therapy (PDT) for non-melanoma skin cancer and other skin diseases. During this time we have undertaken approximately 5000 treatments and this article details the practical aspects of how we treat Bowen’s disease with topical PDT. © 2009 Elsevier B.V. All rights reserved.
Introduction Bowen’s disease (BD), or squamous cell carcinoma in situ, usually presents as a well-defined erythematous plaque on photoexposed sites. Lesions are common on the head and neck and lower limbs, although any site can be involved. A delay in diagnosis is often encountered because the lesion is asymptomatic; early skin changes may be subtle and the clinical features overlap with those seen in many benign conditions such as tinea corporis, discoid eczema, and psoriasis. Histological confirmation might therefore be necessary when clinical differentiation between these diseases is difficult. Several equally efficacious (1-year clearance rates 70—100%) non-surgical treatment options are available for the treatment of BD including topical cryotherapy, 5fluorouracil, imiquimod and photodynamic therapy (PDT) [1]. The distinct advantage of PDT is that it selectively targets tumour cells, leaving the surrounding healthy cells
∗ Corresponding author. Tel.: +44 1382 496227; fax: +44 1382 633925. E-mail address: [email protected] (S.H. Ibbotson).
relatively unaffected; thus causing minimal scarring and a much better cosmetic outcome [2]. The Photobiology Unit in Dundee has undertaken approximately 5000 treatments with topical PDT and has over 10 years of experience in its use for a variety of skin diseases. The Unit is part of the Scottish Photodynamic Therapy Centre, established in 2001, which offers topical and systemic PDT for a diverse range of different cancers, including those of lung, brain and gastrointestinal tract and some non-oncological diseases [3,4]. The dermatology PDT team includes two Consultant Dermatologists, a Consultant Photophysicist, Clinical Scientist, Clinical Nurse Co-ordinator, six photobiology technicians and a specialist dermatology registrar. All treatments are under the supervision of the Lead Consultant Dermatologist and technician-led PDT is carried out on a daily basis, in addition to a weekly clinic run by a specialist registrar who sees new and return patients (SA). Referrals are received from dermatologists in our own department, from other regional dermatology centres in Scotland and from local plastic surgeons and oncologists and all referral letters are screened by the consultant dermatologist in charge of the PDT service (SI). In the following section we shall elaborate in a step-wise fashion, on how we treat BD with topical PDT (Fig. 1).
1572-1000/$ — see front matter © 2009 Elsevier B.V. All rights reserved. doi:10.1016/j.pdpdt.2009.04.001
42
S.K. Attili, S.H. Ibbotson
Figure 1
Step-wise illustration of treatment of BD on the leg with PDT.
Selection of patients Patients attending our outpatient clinics are referred for PDT based on clinical and/or histological diagnosis. The choice of therapy (i.e. PDT vs. alternatives) depends on patient suitability and location/number of lesions. PDT is ideally suited for treatment of large/multiple lesions especially on the lower legs, where ulceration, poor healing and
sub-optimal cosmesis from conventional therapies are particular risks.
Consent Once referred, patients are sent information on PDT along with their appointment for the clinic. We take a history regarding current or previous treatments and relative con-
How we treat Bowen’s disease with topical photodynamic therapy traindications to PDT, such as photosensitivity. We assess the lesion, explain the procedure and obtain written consent for treatment. Patients are specifically questioned about factors which may make them susceptible to poor healing or excess bleeding or less likely to respond well to treatment—– such as peripheral vascular disease, diabetes, anticoagulant therapy or immunosuppression. Patients at risk of poor healing on lower leg sites have ankle-brachial-pressure indices measured and are fitted with compression stockings, pretreatment. All lesions are photographed pre-treatment and mapped on a ‘body-site’ chart. The site and maximum lesion diameter is documented.
Surface preparation Patients are instructed (in the written information sent out with the appointment) to apply vaseline to the lesions for 3 days prior to their PDT clinic appointment, in order to soften the surface crust. Lesions are gently abraded (without local anaesthesia) using a spatula or disposable curette (Stiefel 7 mm), so that the surface crust is removed (Fig. 1a—c). This is supposed to facilitate better absorption of the photosensitising agent-usually Metvix creamTM (Galderma, UK) or 5-aminolaevulinic acid (Manmed Pharmaceuticals, UK). However in a recent small comparative study where each half of 16 lesions (superficial BCC or BD) was randomly assigned to surface preparation (gentle curettage or abrasion with a scalpel) or none and then treated with ALA-PDT; there was no significant difference in the response of lesions based on whether surface preparation was performed or not [5].
Application of photosensitiser MetvixTM is the only drug preparation licensed for use in PDT in the UK. Using a spatula a 1 mm thick layer of MetvixTM (160 mg/g (16%) of methyl aminolevulinate as hydrochloride, Galderma, UK) is applied to the lesion as well as to 5 mm of surrounding normal skin (Fig. 1d—f). The cream is secured with TegadermTM and an occlusive dressing (MeporeTM ) is applied for 3 h, to prevent premature initiation of the PDT effect by natural sunlight (Fig. 1g—i). Patients are allowed to wander around freely during this time, but are instructed to stay away from direct sunlight. We do also use 5-aminolaevulinic acid (5-ALA, 20% (w/v) in oil in water base, Manmed Pharmaceuticals, UK) on a named-patient basis, as an alternative and this is usually applied for 4 h for BD.
Fluorescence with Wood’s light At the end of 3 h (or 4 h for 5-ALA) dressings and excess cream are removed (Fig. 1j—l). Visual fluorescence of the lesion is assessed in a dark room, using Wood’s lamp, graded on a 3-point scale for intensity and specificity and recorded [6]. This combination of the lesion margin visible to the naked eye and the margin defined by fluorescence is used to define the irradiation field, which is demarcated to include a 5 mm rim of clinically normal appearing tissue, and the maximum diameter of the field is documented (Fig. 1m—n). In
43
research and other special circumstances we use an optical biopsy or CCD system to quantitatively assess PpIX fluorescence and map the lesion [7,8].
Local anaesthesia We aim to treat patients without using local anaesthesia as it is otherwise a non-invasive procedure. However, all patients are routinely offered cool air treatment (Cynosure® ) during irradiation, which we feel is of considerable benefit. Topical anaesthetic preparations such as tetracaine (AmetopTM ) have not been shown to have a marked or significant effect on pain relief for PDT for small lesions [9]. However, anecdotally we find AmetopTM may alleviate PDT induced pain partially, when used on large areas such as for treatment of actinic damage on the scalp or lower legs. This may of course be a placebo effect, but in these situations or for patients known to have found PDT to be very painful previously, we do apply AmetopTM for 1 h prior to irradiation, although this requires further study. Occasionally some patients with localised disease might need local anaesthetic (1—2% lignocaine without adrenaline) infiltration [10].
Irradiation Irradiation is performed using one of several light sources available in the department [10]. Regular calibration and dosimetry are performed in-house. The light sources we commonly use are the Aktilite® LED sources. We also use, on a named-patient basis, low irradiance, LED light sources which have been shown to be associated with less pain; and moreover have the potential for ambulatory PDT [11,12]. The light source used and the skin surface irradiance is documented and the duration of time required to deliver a standard dose of 125 J/cm2 for laser and non-LED sources or 37 J/cm2 (75 J/cm2 if using 5-ALA; as our clinical experience suggests that 37 J/cm2 may result in lower clearance rates) for the LED’s is also documented (Fig. 1o—q). Immediately post-irradiation, erythema, oedema and urticaria are noted (Fig. 1r) and pain assessed [13,14]. The treatment cycle as above is repeated at 1 week.
Post-treatment care Lesions are covered with MeporeTM for 24 h following PDT and patients are advised to avoid bright sunlight or intense artificial light exposure to the area for up to 48 h after treatment. They are also advised to expect inflammation and crusting at the site over the ensuing 7—10 days and of the potential risk of infection, pigmentary change and scarring.
Assessment of response All patients are asked to routinely score pain on a visual analogue scale immediately after treatment. Clinical clearance is assessed routinely at 3 months and 1 year after last treatment. All lesions are photographed on review. All patients with partial response at 3-month review are offered two further treatments with PDT (1 week apart) and again followed
44
S.K. Attili, S.H. Ibbotson
Figure 2 Bowen’s disease-left lower eyelid. (a) Before and (b) 1 year following 1× PDT cycle showing residual erythema only with clinical clearance of lesion.
up to 1 year following last treatment. Generally we consider incomplete clearance following four PDT treatments to be a PDT failure; as in our experience, the vast majority of patients who clear, do so within two treatment cycles. Patients would be referred for alternative treatments in this situation. Recurrent disease can be retreated by PDT and this is an advantage of PDT and particularly applicable to large or multiple areas and field change.
Discussion The most common side effect experienced with PDT is pain, with up to 20% of patients describing pain as being ‘severe’ [10]. This can sometimes persist for a few hours after treatment, but is usually maximal during the early part of irradiation. Post-inflammatory hyper or hypopigmentation can also occur. Persistent erythema is often
Figure 3
seen at 3 months but does not necessarily indicate residual disease, but can make assessment of response difficult, at this early time point. We look for any residual surface scale on palpation, which is more likely to indicate residual disease. Field change Bowenoid actinic keratoses are often difficult to treat with most modalities, but we have used PDT with success in this situation. However recurrence of BD within the treated site is common, because of the nature of field change dysplasia. PDT can also be used for treatment of BD in specific sites such as around the eyes and genitals. We have recently presented a case series on the treatment of periocular tumours (including BD) with PDT [15] (Fig. 2). PDT seems to have a distinct advantage of superior tolerance compared to imiquimod for these cases, but this needs to be confirmed in larger studies. In our experience treatment of genital lesions with PDT can also be successful, although local anaesthesia is more likely to be required. Acral BD is
Bowen’s disease-left little finger. (a) Before and (b) 1 year following 1× PDT cycle, showing complete clearance.
How we treat Bowen’s disease with topical photodynamic therapy anecdotally supposed to respond poorly with PDT, however we have had a few successes (Fig. 3). The main limiting factors for PDT at the moment are pain and the inconvenience of hospital attendance. Lowirradiance PDT [11,12] however is quite promising and could be the potential alternative, especially for elderly patients who find the need for hospital attendance limiting. In our experience PDT is the treatment of choice for BD on the lower legs and is ideal for large and multiple lesions; or for patients where other modalities of treatment (surgical or non-surgical) are inappropriate or have failed.
References [1] Morton CA, McKenna KE, Rhodes LE. Guidelines for topical photodynamic therapy: update. British Association of Dermatologists Therapy Guidelines and Audit Subcommittee and the British Photodermatology Group. Br J Dermatol 2008;159(December (6)):1245—66. [2] Morton C, Horn M, Leman J, et al. Comparison of topical methyl aminolevulinate photodynamic therapy with cryotherapy or Fluorouracil for treatment of squamous cell carcinoma in situ: results of a multicenter randomized trial. Arch Dermatol 2006;142(June (6)):729—35. [3] Ibbotson SH, Moseley H, Brancaleon L, et al. Photodynamic therapy in dermatology: Dundee clinical and research experience. Photodiagn Photodyn Ther 2004;1:211—23. [4] Moseley H, Ibbotson S, Woods J, et al. Clinical and research applications of photodynamic therapy in dermatology: experience of the Scottish PDT Centre. Lasers Surg Med 2006;38(June (5)):403—16. [5] Moseley H, Brancaleon L, Lesar AE, et al. Does surface preparation alter ALA uptake in superficial non-melanoma skin cancer in vivo? Photodermatol Photoimmunol Photomed 2008;24:72—5.
45
[6] Ibbotson SH. How we treat a superficial basal cell carcinoma with topical photodynamic therapy in Dundee. Photodiag Photodyn Therapy 2006;3:128—31. [7] Hewett J, Nadeau V, Ferguson J, et al. The application of a compact multispectral imaging system with integrated excitation source to in vivo monitoring of fluorescence during topical photodynamic therapy of superficial skin cancers. Photochem Photobiol 2001;73(3):278—82. [8] Ibbotson SH, Jong C, Lesar A, et al. Characteristics of 5aminolaevulinic acid-induced protoporphyrin IX fluorescence in human skin in vivo. Photodermatol Photoimmunol Photomed 2006;22(April (2)):105—10. [9] Holmes MV, Dawe RS, Ferguson J, Ibbotson SH. A randomised, double-blind, placebo-controlled study of the efficacy of tetracaine gel (Ametop) for pain relief during topical photodynamic therapy. Br J Dermatol 2004;150:337—40. [10] Clark C, Bryden AM, Dawe RS, Moseley H, Ferguson J, Ibbotson SH. Topical 5-aminolaevulinic acid photodynamic therapy for cutaneous lesions: outcome and comparison of light sources. Photoderm Photoimmunol Photomed 2003;19:134—41. [11] Moseley H, Allen JW, Ibbotson S, et al. Ambulatory photodynamic therapy: a new concept in delivering photodynamic therapy. Br J Dermatol 2006;154:747—50. [12] Attili SK, Lesar A, McNeill A, et al. An open pilot study of ambulatory photodynamic therapy (PDT) using a wearable lowirradiance organic LED light source in the treatment of non melanoma skin cancer. Br J Dermatol; in press. [13] Clark C, Dawe RS, Moseley H, Ferguson J, Ibbotson SH. The characteristics of erythema induced by topical 5aminolaevulinic acid photodynamic therapy. Photodermatol Photoimmunol Photomed 2004;20(2):105—7. [14] Kerr AC, Ferguson J, Ibbotson SH. Acute phototoxicity with urticarial features during topical 5-aminolaevulinic acid. photodynamic therapy. Clin Exp Dermatol 2007;32(2):201—2. [15] Attili SK, Murgatroyd H, Ibbotson SH, Fleming CJ. Role of non-surgical therapies in the management of periocular malignancy: a case series. EADV 2008 (abstract).