Successful Therapy with 5-ALA Photodynamic Therapy for Bowen's Disease in a Single Lobulated Nodule Mimicking Genital Warts.

Sir,

Bowen's disease usually presents as a chronic erythematous reddish, scaly patch or plaque, with an irregular margin. Surgical therapy is the first-line modality.[1] Here, we describe a case of Bowen's disease in the perineum fully treated with 5-ALA photodynamic therapy (PDT). A 46-year-old woman presented with a 6-month history of recurrent lobulated nodule in the perineal area. Physical examination revealed a red lobulated nodule in the perineal area [Figure 1a]. The nodule was soft, approximately 2 cm in diameter. The tissue was negative for human papillomavirus DNA test. A biopsied specimen was consistent with Bowen's disease (carcinoma in situ) and showed marked acanthosis in the epidermis with intact basement membrane and disordered atypical keratinocytes throughout the epidermis, with mitotic figures [Figure 1b]. The patient received six cycles of topical 5-ALA PDT every week. The nodule was removed by YAG laser, and 20% 5-ALA solution (Fudan-Zhangjiang Biological Medicine Co. Ltd., Shanghai, China) was then applied to the lesion and 1 cm area around the lesion, for 3 h. Irradiation (100 J/cm2 at 100 mW/cm2) was delivered through a red light-emitting diode (630 nm). A complete response, without recurrence, was achieved for 12 months [Figure 2]. As a form of carcinoma in situ,[1] Bowen's disease usually presents well-defined scaly red patches in patients over 60 year old. It was reported that there is a small risk of progression to invasive squamous cell carcinoma (estimated to be 3%).[1] However, rare variants of Bowen's disease can occur such as fungating, verrucous, or pigmented forms,[23] and these may be misdiagnosed as other benign or malignant neoplasms. Because lesions are rarely described as single lobulated nodules, similar to genital warts in appearance, we confirmed the diagnosis by histopathology. There are many treatments for Bowen's disease including surgical interventions, destructive therapies, topical therapies, and PDT. Surgical excision is the first-line treatment. The limitations of surgical excision include scars, deformation of surrounding tissue, bleeding, and risk for infection. PDT is an effective treatment for various cutaneous and noncutaneous malignancies. It is a nondestructive treatment that achieves satisfactory cosmetic outcome.[4] The common side effect of PDT was a stinging sensation. The patient was satisfied with the cosmetic outcomes of this therapy. In conclusion, we presented a distinctive Bowen's disease case in a young female patient and her lesion was a single lobulated nodule, rather than a typical red plaque. The lesion was not recurrent for 12 months after treatment. In a special area of the body where surgery rarely preserves the functional and structural integrity of the organ, we recommend PDT for treatment of Bowen's disease.

Figure 1

Clinical images before treatment (a). Histopathological findings show proliferation of atypical squamous cells throughout the epidermis, without invasion of the dermis (H and E, ×40) (b)

Figure 2

Clinical images of healthy skin of in the perineal area at 12-month follow-up

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.