Photodynamic therapy in a patient with perianal extramammary Paget's disease

Extramammary Paget's disease (EMPD) is a rare neoplasm of apocrine gland-bearing areas of the skin. One of the most common localizations of such a tumor is the perianal area. Clinically, EMPD appears as a well-defined erythematous velvety plaque, sometimes eczematous and, more rarely, crusted, ulcerated, lichenified, or leucoplakic plaques. Patients frequently complain of pruritus, burning sensation, and pain in the affected site. Surgery and local therapy are the most commonly used therapies. However, surgery is an invasive method. Both surgery and local therapy are complicated by a high recurrence rate (40% local recurrence rate after imiquimod [1], 34% local recurrence rate after radiation therapy [1], 26.3% local recurrence rate after wide local excision [2]). For these reasons, several less-invasive and more effective treatments have been recently proposed, including photodynamic therapy (PDT) [3], [4], [5].

PDT is based on the use of a photosensitizer that selectively accumulates in the tumor and generates reactive oxygen species, which leads to the death of tumor cells [6,7].

A recent systematic review was published on the use of PDT for EMPD [8]. . The search for publications was carried out on the site pubmed.com, the publication period was chosen from 2000 to 2022. The authors analyzed the results of PDT studies in 114 patients with EMPD. In the analyzed publications for PDT, ointment with 5-aminolevulinic acid (5-ALA) (29 patients) and 5-ALA methyl ester (67 patients) were most often used. Besides, porfimer sodium (4 patients) and a hematoporphyrin derivative (11 patients) were also applied. In 3 patients, treatment was performed with 5-ALA and porfimer sodium on different EMPD lesions or sequentially on the same lesion. No studies were found on the efficacy of PDT in EMPD patients with photosensitizer chlorine. According to the data presented in the review, complete regression of EMPD foci was obtained on average in 40% of patients. Relapses were observed only in 21% of patients during the follow-up period from 2 to 29 months. Both the immediate effect of therapy and long-term results depended on the area of the lesion. All the cases of treatment of foci of EMPD large size (more than 5 × 5 cm) by PDT, which we found in the literature, were not accompanied by a complete cure. In a study by X.L. Wang et al. [9] lesion sizes in one of the patients were 5 × 6 and 5 × 9 cm, and in the patient described in the study by V. Madan et al. [13], the lesion size was 10 × 10 cm. In both cases, after PDT, only partial regression of the tumor was achieved. Relapses occurred in most cases with a large area of damage too. In a study by Q. Li et al. [10] showed a relationship between the frequency of relapses and the area of the lesion subjected to PDT. Within 12 months after PDT, two relapses were registered in patients with a lesion area of more than 4 cm2. None of the patients with a focus area of less than 4 cm2 had a recurrence of the disease during these periods.

The efficacy of PDT can be enhanced with the combination of other treatments such as surgery, imiquimod, or laser ablation [11].

PDT in patients with EMPD can be supplemented with fluorescence diagnostics (FD) [12]. M. Wan et al. [13] showed a strong correlation between the boundaries of the tumor lesion, determined by FD with 5-ALA, and the boundaries, determined by biopsy with the histological examination in 21 patients with EMPD. In the study by M. Wu et al. [14] in 36 patients with EMPD, FD with 5-ALA revealed a tumor process that was not detectable during visual examination in 37 (28.5%) of 130 sections.

We describe here the case of a patient with a non-invasive vulvar EMPD successfully treated with chlorin-PDT. Photosensitizers based on chlorin e6 are widely used in clinical practice in Russia. It is used for PDT of skin cancer, breast cancer, vulvar cancer, esophageal cancer, central lung cancer and other localizations [7,15,16].

留言 (0)

沒有登入
gif