Cryosurgery versus curettage for intraepidermal carcinoma: A randomized controlled trial

BACKGROUND

Cryosurgery is a common destructive treatment method for intraepidermal carcinoma (IEC) above the knee. Curettage alone is a simple, non-aggressive and inexpensive treatment method commonly used on benign skin lesions. However, only one study has assessed curettage for treatment of IEC.

OBJECTIVE

We aimed to (1) compare the effectiveness of cryosurgery (standard method) to curettage (experimental method) for treatment of IEC in regard to overall clearance rates at 1-year follow-up, and (2) investigate whether wound healing times differed between the treatment groups.

METHODS

In this randomized and controlled, non-inferiority trial, adult patients with one or more IEC with a diameter of 5-20 mm, located above the knee and suitable for destructive treatment were recruited from Sahlgrenska University Hospital (Gothenburg, Sweden). Lesions were randomized to treatment with either cryosurgery or curettage. Wound healing was assessed by a nurse after 4-6 weeks and through self-report forms. Overall clearance was assessed by a dermatologist after 1 year.

RESULTS

In total, 183 lesions in 147 patients were included, with 93 lesions randomized to cryosurgery and 90 to curettage. Eighty-eight (94.6%) of the lesions in the cryosurgery group and 71 (78.9%) in the curettage group showed an overall clearance at the 1-year follow-up visit (p = 0.002). The non-inferiority analysis was inconclusive. Curettage resulted in both shorter self-reported wound healing times (mean time 3.1 vs. 4.8 weeks, p < 0.001) and a larger proportion of healed wounds after 4-6 weeks (p < 0.001).

CONCLUSIONS

Cryosurgery and curettage both result in high clearance rates for treatment of IEC, but cryosurgery is significantly more effective. On the other hand, curettage may result in shorter wound healing times.

Skin cancer: understanding the journey of transformation from conventional to advanced treatment approaches

Skin cancer is a global threat to the healthcare system and is estimated to incline tremendously in the next 20 years, if not diagnosed at an early stage. Even though it is curable at an early stage, novel drug identification, clinical success, and drug resistance is another major challenge. To bridge the gap and bring effective treatment, it is important to understand the etiology of skin carcinoma, the mechanism of cell proliferation, factors affecting cell growth, and the mechanism of drug resistance. The current article focusses on understanding the structural diversity of skin cancers, treatments available till date including phytocompounds, chemotherapy, radiotherapy, photothermal therapy, surgery, combination therapy, molecular targets associated with cancer growth and metastasis, and special emphasis on nanotechnology-based approaches for downregulating the deleterious disease. A detailed analysis with respect to types of nanoparticles and their scope in overcoming multidrug resistance as well as associated clinical trials has been discussed.

Durable Clearance Rate of Photodynamic Therapy for Bowen Disease and Cutaneous Squamous Cell Carcinoma: A Systematic Review and Meta-Analysis

BACKGROUND

Although surgery is the treatment of choice for Bowen disease (BD) and cutaneous squamous cell carcinoma (cSCC), nonsurgical treatments such as photodynamic therapy (PDT) may be preferred for select tumors. Previous meta-analysis have failed to gather strong evidence to recommend PDT.

OBJECTIVE

This study evaluates the effectiveness of PDT in the treatment of cSCC and BD for clearance rate (CR) after 1 year.

METHODS

A literature search of studies of biopsy-proven BD and cSCC treated with PDT was performed. Pooled CRs were estimated. Subgroup analyses were performed based on follow-up, treatment regimen, lesion size, and site.

RESULTS

Forty-three studies were included, enrolling 1943 BD lesions and 282 SCC lesions. Pooled CRs for BD and SCC were 76% (95% CI: 71%-80%; I2 = 78.9%) and 51% (95% CI: 35%-66%; I2 = 85.7%), respectively.

CONCLUSION

Our findings support the selective use of PDT for BD; however, patients should be advised of potential for recurrence. Although PDT can be used for certain cases of cSCC, the high rate of treatment failure necessitates close surveillance for residual or recurrent disease. Further studies are needed to justify the usage of PDT in the treatment of BD and cSCC.

Photodynamic therapy utilizing 10% ALA nano-emulsion gel and red-light for the treatment of squamous cell carcinoma in-situ on the trunk and extremities: Pilot study and literature update

BACKGROUND

Data evaluating the effectiveness of photodynamic therapy (PDT) with aminolevulinic acid (ALA) 10% nanoemulsion gel and red-light LED lamp for the treatment of squamous cell carcinoma in situ (SCCis) on the trunk and extremities is limited. Our study sought to investigate the safety and efficacy of utilizing ALA 10% gel with red-light lamp for the treatment of SCCis on the trunk and extremities.

METHODS

A single center prospective study of 12 patients with biopsy proven SCCis underwent one or two cycles of red-light PDT with ALA 10 % gel and 3 hours incubation period. Each cycle consisted of two treatments approximately 10 days apart. All participants had a biopsy for histologic evaluation 4 weeks following the last treatment.

RESULTS

All patients achieved clinical and histologic clearance following either one or two cycles at the 4-week post treatment follow up period. The majority of lesions were located on the extremities (n=10) with the remainder located on the trunk (n=2). The mean diameter of the lesions was 1.83 cm. Mild pain was noted in patients, with no interruption of treatment.

CONCLUSIONS

Our study indicates that ALA 10% gel with a red-light lamp is a safe and effective treatment option for SCCis on the trunk and extremities.

European Dermatology Forum guidelines on topical photodynamic therapy 2019 Part 1: treatment delivery and established indications - actinic keratoses, Bowen's disease and basal cell carcinomas

Topical photodynamic therapy (PDT) is a widely approved therapy for actinic keratoses, Bowen's disease (squamous cell carcinoma in situ), superficial and certain thin basal cell carcinomas. Recurrence rates when standard treatment protocols are used are typically equivalent to existing therapies, although inferior to surgery for nodular basal cell carcinoma. PDT can be used both as lesional and field therapies and has the potential to delay/reduce the development of new lesions. A protocol using daylight to treat actinic keratoses is widely practised, with conventional PDT using a red light after typically a 3-h period of occlusion employed for other superficial skin cancer indications as well as for actinic keratoses when daylight therapy is not feasible. PDT is a well-tolerated therapy although discomfort associated with conventional protocol may require pain-reduction measures. PDT using daylight is associated with no or minimal pain and preferred by patient. There is an emerging literature on enhancing conventional PDT protocols or combined PDT with another treatment to increase response rates. This guideline, published over two parts, considers all current approved and emerging indications for the use of topical PDT in dermatology, prepared by the PDT subgroup of the European Dermatology Forum guidelines committee. It presents consensual expert recommendations reflecting current published evidence.

Photodynamic therapy for treatment of usual-type vulvar intraepithelial neoplasia: a case report and literature review

Vulvar intraepithelial neoplasia (VIN) is a pre-malignant condition of the vulvar skin that is found in 50% to 70% of patients with vulvar squamous cell cancer and is regarded as a precursor of vulvar tumors. Thus far, treatment remains lesion- and patient-specific. Here, we describe a VIN patient who presented with a 15-month history of large lesions in the bilateral labium, associated with human papillomavirus infection. The lesions were inappropriate for surgical excision and laser ablation because of their size; therefore, they were treated with photodynamic therapy and concurrent topical 5-aminolevulinic acid hydrochloride. The patient showed no recurrence throughout 2 years of post-treatment follow-up, and reported only slight pain during treatment. Moreover, no significant side effects or scarring were detected. Thus, we conclude that photodynamic therapy can be a useful alternative treatment for large VIN in the bilateral labium that cannot be excised or ablated.

Photodynamic therapy for skin cancer: How to enhance drug penetration?

Photodynamic therapy (PDT) induced by protoporphyrin IX (PpIX) has been widely used in dermatological practices such as treatment of skin cancers. Clearance rate depends on different factors such as light irradiation, skin oxygenation and drug penetration. The poor penetration of 5-aminolevulinic acid (5-ALA) with topical application is limited and restrains the production of PpIX which could restrict PDT outcomes. This review will focus on techniques already used to enhance drug penetration in human skin, and will present their results, advantages, and drawbacks. Chemical and physical pretreatments will be discussed. Chemical pre-treatments comprise of drug formulation modification, use of agents that modify the heme cycle, enhance PpIX formation, and the combination of differentiation-promoting agent prior to PDT. On the other hand, physical pretreatments affect the skin barrier by creating holes in the skin or by removing stratum corneum. To promote drug penetration, iontophoresis and temperature modulation are interesting alternative methods. Cellular mechanisms enrolled during chemical or physical pretreatments have been investigated in order to understand how 5-ALA penetrates the skin, why it is preferentially metabolized in PpIX in tumour cells, and how it could be accumulated in deeper skin layers. The objective of this review is to compare clinical trials that use innovative technology to conventional PDT treatment. Most of these pretreatments present good or even better clinical outcomes than usual PDT.

Methyl aminolevulinate-based photodynamic therapy of Bowen´s disease: Observational study of 21 lesions

BACKGROUND

Although surgical removal is the treatment of choice in Bowen's disease (BD), there are cases in which by age, comorbidities, use of anticoagulants, location, cosmetic result, or size, it is preferable to use other treatments such as cryotherapy, 5-fluorouracil cream, imiquimod 5% cream or photodynamic therapy (PDT). Efficacy of PDT in BD is supported by substantial research and clinical data.

OBJECTIVES

This study aimed to evaluate the long term effectiveness of methyl aminolevulinate-PDT (MAL/PDT) on a wide range of Bowen lesions in different locations and sizes.

METHODS

Patients diagnosed with BD were treated in 3 sessions with a 4-week interval in between with MAL/PDT between January 2016 and January 2017 in a private clinic. Clinical response and relevant patient and tumour characteristics were analyzed during the first year after start of the PDT sessions.

RESULTS

In total, 21 BD lesions in 18 patients were included in the study. Complete regression (CR) after 3rd PDT session was 87.5% and 100% at the 6-month follow-up. Treatment was well tolerated and local adverse reactions were very scarce. No recurrence was observed at 12-month follow-up. Cosmetic outcome at 12 months was good or excellent in 100% of patients.

CONCLUSIONS

MAL/PDT is an effective, non invasive and safe treatment modality for BD with excellent cosmesis.

Simple and Selective HPLC-UV/Vis Bioanalytical Method to Determine Aluminum Phthalocyanine Chloride in Skin Permeation Studies

Considering the feasibility of the aluminum phthalocyanine chloride (AlPcCl) application in the topical photodynamic therapy of cutaneous tumors and the lack of HPLC methods capable of supporting skin permeation experiments using this compound, the aim of this study was to obtain a simple and selective chromatographic method for AlPcCl determination in skin matrices. A HPLC-UV/Vis method was developed using a normal-phase column operating at 30°C, an isocratic mobile phase of methanol : phosphoric acid (0.01 M) at 1.5 mL/min, and detection at 670 nm. The method exhibited (i) selectivity against various contaminants found in the different skin layers, (ii) high drug extraction capacity from the hair follicle (>70%) and remaining skin (>80%), and (iii) low limits of detection and of quantification (0.03 and 0.09 μg/mL, resp.). The method was also linear in the range from 0.1 to 5.0 µg/mL (r = 0.9994) and demonstrated robustness with regard to experimental chromatographic parameters according to a factorial design. Lastly, the developed method was successfully tested in in vitro skin permeation studies of AlPcCl, proving its effectiveness in the development of pharmaceutical delivery systems containing this drug for topical photodynamic therapy of skin cancers.

Effectiveness of photodynamic therapy in Bowen's disease: a retrospective observational study in 423 lesions

BACKGROUND

Photodynamic therapy (PDT) is a well-known technique that is often used for treating superficial precancerous and cancerous skin lesions. However, only a handful of studies, with a relatively small number of treated lesions, have been carried out on the effectiveness of PDT for Bowen's disease (BD).

OBJECTIVES

This study aimed to assess the effectiveness and recurrence risk of PDT in the treatment of BD. The secondary objectives were to determine what factors affected the response rates and the cosmetic result of the treatment.

METHOD

In this retrospective observational study, the electronic patient charts at Sahlgrenska University Hospital (SUH) in Gothenburg, Sweden, were searched to find all patients diagnosed with BD who were treated with PDT between 1 January 2002 and 31 December 2014. Data were collected regarding clinical response at the first follow-up visit, recurrences during later follow-up visits and other relevant patient and tumour characteristics.

RESULTS

In total, 423 BD lesions in 335 patients were included in the study. The mean FU duration was 11.2 months (range 0.2-151 months). The complete response rate at the first FU visit was 77.5% for all BD lesions. During later FU visits, another 60 recurrences were observed, which resulted in a recurrence rate of 18.3%. Thus, the overall clearance rate after FU was 63.4% for all BD lesions. Significant risk factors for unsuccessful treatment in this study were large lesion size (>2 cm) and a single PDT session.

CONCLUSION

This study shows that PDT is a relatively effective treatment modality for BD.

Photodynamic Therapy and Non-Melanoma Skin Cancer

Non-melanoma skin cancer (NMSC) is the most common malignancy among the Caucasian population. Photodynamic therapy (PDT) is gaining popularity for the treatment of basal cell carcinoma (BCC), Bowen's disease (BD) and actinic keratosis (AK). A topical or systemic exogenous photosensitiser, results in selective uptake by malignant cells. Protoporphyrin IX (PpIX) is produced then activated by the introduction of a light source. Daylight-mediated MAL (methyl aminolaevulinate) PDT for AKs has the advantage of decreased pain and better patient tolerance. PDT is an effective treatment for superficial BCC, BD and both individual and field treatment of AKs. Excellent cosmesis can be achieved with high patient satisfaction. Variable results have been reported for nodular BCC, with improved outcomes following pretreatment and repeated PDT cycles. The more aggressive basisquamous, morphoeic infiltrating subtypes of BCC and invasive squamous cell carcinoma (SCC) are not suitable for PDT. Prevention of "field cancerization" in organ transplant recipients on long-term immunosuppression and patients with Gorlin syndrome (naevoid basal cell carcinoma syndrome) is a promising development. The optimisation of PDT techniques with improved photosensitiser delivery to target tissues, new generation photosensitisers and novel light sources may expand the future role of PDT in NMSC management.