Efficacy of photodynamic therapy for the treatment of Bowen’s disease: An updated systematic review and meta-analysis of randomized controlled trials

Photodynamic Therapy for the Treatment of Bowen's Disease: A Review on Efficacy, Non-Invasive Treatment Monitoring, Tolerability, and Cosmetic Outcome

Bowen's disease represents the in situ form of cutaneous squamous cell carcinoma; although it has an excellent prognosis, 3-5% of lesions progress to invasive cutaneous squamous cell carcinoma, with a higher risk in immunocompromised patients. Treatment is therefore always necessary, and conventional photodynamic therapy is a first-line option. The aim of this review is to provide an overview of the clinical response, recurrence rates, safety, and cosmetic outcome of photodynamic therapy in the treatment of Bowen's disease, considering different protocols in terms of photosensitizers, light source, and combination treatments. Photodynamic therapy is a valuable option for tumors at sites where wound healing is poor/delayed, in the case of multiple and/or large tumors, and where surgery would be difficult or invasive. Dermoscopy and reflectance confocal microscopy can be used as valuable tools for monitoring the therapeutic response. The treatment is generally well tolerated, with mild side effects, and is associated with a good/excellent cosmetic outcome. Periodic follow-up after photodynamic therapy is essential because of the risk of recurrence and progression to cSCC. As the incidence of keratinocyte tumors increases, the therapeutic space for photodynamic therapy will further increase.

Bowen's disease of the vulva and perianal area in a SLE patient successfully treated with Photodynamic therapy: A case report

Photodynamic therapy (PDT) has emerged as a non-invasive treatment modality for superficial skin cancers. It has the advantage of greater tolerance and providing better cosmetic outcomes than conventional treatment methods. Because of the rarity of extensive Bowen's disease located in the genital area, evidence of efficacy for therapies is mainly based on case reports and clinical experience. This report presents a case of a 32-year-old female with Bowen's disease of the vulva and perianal area with systemic lupus erythematosus successfully treated by 5-aminolaevulinic acid PDT. There was no evidence of recurrence after five-years of follow-up.

Long-term follow up of ALA 10% gel and red-light photodynamic therapy for the treatment of squamous cell carcinoma in situ

Photodynamic Therapy (PDT) with 10% aminolevulinic acid (ALA) gel and narrow-band red light has been previously shown to be safe and effective for the treatment of squamous cell carcinoma in situ (SCCis) on the trunk and extremities. However, there is a paucity of data in the literature evaluating long-term disease recurrence after PDT. Hence, we performed a follow-up study in which nine of the original twelve patients from our pilot study returned 29-40 months after their last PDT treatment. All patients were clinically clear of disease and only one of seven patients biopsied had residual disease, indicating a long-term clearance rate of 88%. Cosmetic outcomes and patient satisfaction were favorable. Our data supports that red-light PDT with 10% ALA gel can achieve long-term clinical and histopathologic disease clearance and is a viable alternative to surgery for select SCCis.

Bowen's Disease

Bowen's disease (BD) is an in-situ squamous cell carcinoma of epidermis. The etiology of BD is multifactorial with high incidence among Caucasians. BD is common in photo-exposed areas of skin, but other sites can also be involved. Lesions are usually solitary. The morphology of BD differs based on age of the lesion, site of origin, and the degree of keratinization. BD is considered as the "lull before the storm," which precedes an overt squamous cell carcinoma. Histopathology is the gold standard diagnostic modality to confirm the diagnosis. Immunohistochemistry, dermoscopy, and reflectance confocal microscopy are the adjuvant modalities used in the diagnosis of BD. The treatment depends on various factors like site, size, immune status, patient's age, esthetic outcome, etc. The available therapeutic modalities include topical chemotherapy, surgical modalities, light-based modalities, and destructive therapies. It requires a combined effort of dermatologist, oncosurgeon, and plastic surgeon to plan and execute the management in various presentations of BD.

The Efficacy of Topical Photodynamic Therapy in Precancerous Lesions of the Skin: A Literature Review

Precancerous skin lesions are associated with high probability of malignant transformation to squamous cell carcinoma. Early detection and management are necessary to improve prognosis and outcomes. Literatures showed that topical photodynamic therapy (PDT) is a promising treatment method which can be successfully applied in several conditions in dermatology. This study aims to review the efficacy of topical PDT for various precancerous lesions in dermatology, such as actinic keratosis, Bowen disease, and Bowenoid papulosis.

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.