Photodynamic therapy with epidermal ablation using fractional carbon-dioxide laser in the treatment of Bowen's disease: A case series

Efficacy of interventions for cutaneous squamous cell carcinoma in situ (Bowen's disease): A systematic review and meta-analysis of proportions

BACKGROUND

Cutaneous squamous cell carcinoma in situ (Bowen's disease) is a precancerous condition confined to the epidermis of the skin. Despite the critical need for effective interventions to halt its progression, there remains a notable shortage of comprehensive data comparing the efficacy of various therapeutic approaches.

OBJECTIVES

This systematic review and meta-analysis endeavour to compare the different efficacies of interventions by investigating and synthesizing data from numerous trials.

METHODS

A pre-defined protocol was registered in PROSPERO (CRD42021242224, registration date: 16 April 2021). Systematic searches in Medline, Embase and Central, along with manual trial register searches, identified studies reporting lesion clearance rates (LCR), participant clearance rates (PCR) or recurrence rates (date of last search: 12 June 2024). Quality assessment followed guidelines from the National Heart, Lung, and Blood Institute (NHLBI). After the study arms were categorized into treatment groups and groups of study quality, the proportions were pooled using the generalized linear mixed model (GLMM) as meta-analytical method.

RESULTS

A comprehensive inclusion of 71 studies facilitated an evaluation of 3783 lesions for LCR, 1225 patients for PCR, 4073 lesions for lesion recurrence rates (LRR) and 740 patients for participant recurrence rates (PRR). Surgery demonstrated the highest LCR and PCR (0.97, 95% confidence interval (CI): 0.90-0.99) and the lowest LRR (0.04, 95% CI: 0.02-0.07).

CONCLUSIONS

This study provides a thorough overview of reported efficacy outcomes for practice-relevant interventions for Bowen's disease. Surgery outperformed other treatments for Bowen's disease. For the other intervention groups, it was not possible to show clear differences in effectiveness: LCR, PCR, LRR and PRR showed various treatment rankings, and the comparability was restricted by different numbers of studies between treatment groups and outcome measures, methodical and clinical heterogeneity. Further high-quality studies are needed to investigate practice-relevant interventions for Bowen's disease.

Phototherapy as a Treatment for Dermatological Diseases, Cancer, Aesthetic Dermatologic Conditions and Allergenic Rhinitis in Adult and Paediatric Medicine

The development of light-emitting diodes (LEDs) has led to an increase in the use of lighting regimes within medicine particularly as a treatment for dermatological conditions. New devices have demonstrated significant results for the treatment of medical conditions, including mild-to-moderate acne vulgaris, wound healing, psoriasis, squamous cell carcinoma in situ (Bowen's disease), basal cell carcinoma, actinic keratosis, and cosmetic applications. The three wavelengths of light that have demonstrated several therapeutic applications are blue (415 nm), red (633 nm), and near-infrared (830 nm). This review shows their potential for treating dermatological conditions. Phototherapy has also been shown to be an effective treatment for allergenic rhinitis in children and adults. In a double-anonymized randomized study it was found that there was 70% improvement of clinical symptoms of allergic rhinitis after intranasal illumination by low-energy narrow-band phototherapy at a wavelength of 660 nm three times a day for 14 consecutive days. Improvement of oedema in many patients with an age range of 7-17 were also observed. These light treatments can now be self-administered by sufferers using devices such as the Allergy Reliever phototherapy device. The device emits visible light (mUV/VIS) and infra-red light (660 nm and 940 nm) wavelengths directly on to the skin in the nasal cavity for a 3 min period. Several phototherapy devices emitting a range of wavelengths have recently become available for use and which give good outcomes for some dermatological conditions.

Efficacy of Photodynamic Therapy for the Treatment of Bowen's Disease: A Meta-Analysis of Randomized Controlled Trials

BACKGROUND

Photodynamic therapy is an established treatment option for Bowen's disease. Our meta-analysis was aimed at evaluating the efficacy and recurrence of photodynamic therapy or other topical treatments (5-fluorouracil, cryotherapy) and of photodynamic therapy alone or in combination with other therapies (ablative fractional CO2 laser or plum-blossom needle) for the treatment of Bowen's disease.

METHODS

Trials that met our inclusion criteria were identified from PubMed, EMBASE, Web of Science, and Cochrane Library databases, and meta-analyses were conducted with RevMan V.5.4. The risk of bias was estimated with the Cochrane Collaboration's risk of bias tools. Complete response rate, recurrence, pain/visual analogue scale score, cosmetic outcome, and adverse events were considered as outcomes.

RESULTS

Of the 2,439 records initially retrieved, 8 randomized controlled trials were included in this meta-analysis. According to our analyses, photodynamic therapy exhibited a significantly higher complete response rate (RR = 1.36, 95% CI [1.01, 1.84], I2 = 86%, p = 0.04), less recurrence (RR = 0.53, 95% CI [0.30, 0.95], I2 = 0%, p = 0.03), and better cosmetic outcome (RR = 1.34, 95% CI [1.15, 1.56], I2 = 0%, p = 0.0002) compared with other treatments. Moreover, there was a significant difference between the complete response rate of photodynamic therapy combined with ablative fractional CO2 laser and that of photodynamic therapy (RR = 1.85, 95% CI [1.38, 2.49], I2 = 0%, p < 0.0001). Photodynamic therapy combined with ablative fractional CO2 laser or plum-blossom needle also showed significantly less recurrence (RR = 0.21, 95% CI [0.09, 0.51], I2 = 0%, p = 0.0005) and a lower visual analogue scale score (RR = 0.51, 95% CI [0.06, 0.96], I2 = 0%, p = 0.03) than photodynamic therapy alone. However, there was no significant difference in the complete response rate between photodynamic therapy combined with ablative continuous CO2 laser and photodynamic therapy combined with ablative fractional CO2 laser (RR = 1.00, 95% CI [0.54, 1.86], I2 not applicable, p = 1.00).

CONCLUSIONS

This meta-analysis shows that photodynamic therapy can be used in the treatment of Bowen's disease with better efficacy, less recurrence, and better cosmetic outcomes than cryotherapy and 5-FU. Some methods, including ablative fractional CO2 laser, can be applied in combination with photodynamic therapy to improve efficacy. However, which laser-assisted photodynamic therapy scheme has the most advantages in the treatment of Bowen's disease warrants further exploration.

Photodynamic therapy: A hot topic in dermato-oncology

Photodynamic therapy (PDT) is a modern, non-invasive therapeutic method used for the destruction of various cells and tissues. It requires the simultaneous presence of three components: a photosensitizer (PS), a light source and oxygen. Precancerous skin lesions are conditions associated with a high likelihood of malignant transformation to squamous cell carcinoma. Data available so far indicate that PDT is a promising treatment method which can be successfully employed in several medical fields including dermatology, urology, ophthalmology, pneumology, cardiology, dentistry and immunology. Numerous authors therefore have studied this technique in order to improve its efficacy. As a result, significant advancement has been achieved with regard to PSs and drug delivery systems. Substantial progress was also obtained with respect to PDT for the treatment of precancerous skin lesions, several authors focusing their efforts on the study of daylight-PDT and on identifying methods of decreasing technique-related pain. This review reports on the most recent findings in PDT, with emphasis on cutaneous precancerous lesions.