Photodynamic therapy and lip vermilion dysplasia: a pilot study

5-Aminolevulinic acid photodynamic therapy for early-stage lip squamous cell carcinoma

BACKGROUND

Squamous cell carcinoma (SCC) of the lip removed by surgery may cause lip dysfunction and scar. ALA-PDT (5-Aminolevulinic acid photodynamic therapy) is a minimally invasive treatment for superficial SCC in situ. However, few studies reported the use of topical ALA-PDT to manage lip SCC.

METHODS

Between 2015 and 2017, 6 patients with Tis to T2 lip squamous cell carcinoma without evidence of lymph node spread, were treated with topical ALA-PDT at Shanghai Skin Disease Hospital. Clinical responses and side effect were evaluated according to the Response Evaluation Criteria in Solid Tumors (RECIST) at 1 month, 6 months, 12 months and 24 months after ALA-PDT.

RESULTS

All of the 6 patients achieved complete response (CR) by 2-7 sessions of ALA-PDT. There was no relapse during 24 months follow up for 4 patients. Two out of 6 patients relapsed at 10 months and 20 months post PDT but achieved CR again by 1-3 more sessions of PDT. There was no functional or aesthetic problem.

CONCLUSION

Topical 5-Aminolevulinic acid photodynamic could be considered a potential alternative therapeutic option for early-stage lip squamous cell carcinoma without lymph node spread.

Treatment of squamous cell carcinoma of the lip using Foscan-mediated photodynamic therapy

Carcinoma of the lip is a common cancer of the head and neck area; its incidence is approximately one-quarter that for oral cavity cancers. It occurs most frequently on the lower lip of elderly males. This non-randomized Phase II study aimed to estimate the complete response (CR) rate to Foscan-mediated photodynamic therapy (Foscan-PDT) in patients with primary cancer of the lip, duration of CR, and the tolerability and safety of Foscan-PDT. Twenty-five patients with squamous cell carcinoma (SCC) of the lip (Tis, T1, T2/N0/M0) and Karnofsky status > or = 70 received 0.15 mg/kg Foscan intravenously, followed 4 days later by a single non-thermal illumination of the tumour (light dose 20 J/cm2, irradiance 100 mW/cm2, lambda=652 nm). Response was determined after 12 weeks and mean follow up is 424 days so far. After 12 weeks, 96% of cases (24/25) showed CR, and all CRs were confirmed by biopsy. The most common adverse event was swelling and local pain at the treatment site. Tumour recurrence was observed in two patients 4 and 18 months after PDT. One patient developed a single lymph node metastasis 7 months after therapy. Photosensitivity reactions occurred in five patients. The functional results were excellent in all patients without any signs of limited mouth opening or impaired lip closure. The cosmetic outcome was better than after surgical therapy. Foscan-PDT is an effective treatment modality for small primary tumours of the lips. Foscan-PDT yields complete response rates comparable to those published for surgery or radiotherapy without causing major toxicity. It allows preservation of form and function and does not compromise future treatment options for recurrent, residual or second primary disease.

Photodynamic therapy in dermatology

The combination of light and chemicals to treat skin diseases is widely practiced in dermatology. Within this broad use of light and drugs, in recent years the concept of photodynamic therapy (PDT) has emerged. PDT is a promising modality for the management of various tumors and nonmalignant diseases, based on the combination of a photosensitizer that is selectively localized in the target tissue and illumination of the lesion with visible light, resulting in photodamage and subsequent cell death. Moreover, the fluorescence of photosensitizing compounds is also utilized as a helpful diagnostic tool for the detection of neoplastic tissue. Intensive basic and clinical research culminated in the worldwide approval of PDT for bladder, esophageal, and lung cancer. The expanding use of this relatively new therapeutic modality in dermatology at many centers around the world has revealed its efficacy for the treatment of cutaneous precancer and cancer, as well as selected benign skin disorders. The following article summarizes the main principles of PDT considering the most recent developments and provides a comprehensive synopsis of the present status of the use of PDT in dermatology. (J Am Acad Dermatol 2000;42:389-413.)

LEARNING OBJECTIVE

At the conclusion of this learning activity, participants should be able to describe the basic concepts of PDT, including fundamental knowledge of the most relevant photosensitizers, the light sources, the mechanisms involved in PDT-mediated cell destruction, as well as the indications and limitations of photodynamic treatment of skin diseases.

Oral leukoplakia: a clinicopathological review

Leukoplakia is the most common premalignant or potentially malignant lesion of the oral mucosa. It seems preferable to use the term leukoplakia as a clinical term only. When a biopsy is taken, the term leukoplakia should be replaced by the diagnosis obtained histologically. The annual percentage of malignant transformation varies in different parts of the world, probably as a result of differences in tobacco and dietary habits. Although epithelial dysplasia is an important predictive factor of malignant transformation, it should be realized that not all dysplastic lesions will become malignant. On the other hand non-dysplastic lesions may become malignant as well. In some parts of the world the tongue and the floor of the mouth can be considered to be high-risk sites with regard to malignant transformation of leukoplakia, while this does not have to be the case in other parts of the world. The cessation of tobacco habits, being the most common known aetiological factor of oral leukoplakia, has been shown to be an effective measure with regard to the incidence of leukoplakia and, thereby, the incidence of oral cancer as well. Screening for oral precancer may be indicated in individuals at risk.