Parameters associated with severe pain during photodynamic therapy: results of a large Scottish series

Photodynamic therapy utilizing 10% ALA nano-emulsion gel and red-light for the treatment of squamous cell carcinoma in-situ on the trunk and extremities: Pilot study and literature update

BACKGROUND

Data evaluating the effectiveness of photodynamic therapy (PDT) with aminolevulinic acid (ALA) 10% nanoemulsion gel and red-light LED lamp for the treatment of squamous cell carcinoma in situ (SCCis) on the trunk and extremities is limited. Our study sought to investigate the safety and efficacy of utilizing ALA 10% gel with red-light lamp for the treatment of SCCis on the trunk and extremities.

METHODS

A single center prospective study of 12 patients with biopsy proven SCCis underwent one or two cycles of red-light PDT with ALA 10 % gel and 3 hours incubation period. Each cycle consisted of two treatments approximately 10 days apart. All participants had a biopsy for histologic evaluation 4 weeks following the last treatment.

RESULTS

All patients achieved clinical and histologic clearance following either one or two cycles at the 4-week post treatment follow up period. The majority of lesions were located on the extremities (n=10) with the remainder located on the trunk (n=2). The mean diameter of the lesions was 1.83 cm. Mild pain was noted in patients, with no interruption of treatment.

CONCLUSIONS

Our study indicates that ALA 10% gel with a red-light lamp is a safe and effective treatment option for SCCis on the trunk and extremities.

Early and Late Onset Side Effects of Photodynamic Therapy

Photodynamic Therapy (PDT) is a non-invasive treatment successfully used for neoplastic, inflammatory and infectious skin diseases. One of its strengths is represented by the high safety profile, even in elderly and/or immuno-depressed subjects. PDT, however, may induce early and late onset side effects. Erythema, pain, burns, edema, itching, desquamation, and pustular formation, often in association with each other, are frequently observed in course of exposure to the light source and in the hours/days immediately after the therapy. In particular, pain is a clinically relevant short-term complication that also reduces long-term patient satisfaction. Rare complications are urticaria, contact dermatitis at the site of application of the photosensitizer, and erosive pustular dermatosis. Debated is the relationship between PDT and carcinogenesis: the eruptive appearance of squamous cell carcinoma (SCC) in previously treated areas has been correlated to a condition of local and/or systemic immunosuppression or to the selection of PDT-resistant SCC. Here we review the literature, with particular emphasis to the pathogenic hypotheses underlying these observations.

Ambulatory photodynamic therapy using low irradiance inorganic light-emitting diodes for the treatment of non-melanoma skin cancer: an open study

BACKGROUND/PURPOSE

Conventional photodynamic therapy (PDT) can be inconvenient and uncomfortable. We studied low irradiance PDT using an ambulatory inorganic light-emitting diode.

METHODS

Fifty-three patients with 61 lesions [superficial basal cell carcinoma (n = 30), Bowen's disease (n = 30), and actinic keratosis (AK; n = 1)] were studied. Two treatments of ambulatory PDT were undertaken 1 week apart (one treatment for AK). Clinical response was determined at 3 months, and the treatment cycle was repeated if there was residual disease. The endpoints assessed were pain during treatment (numerical rating scale (NRS); 0-10) and outcome at 1 year. Twenty-three of these patients also received conventional PDT to separate lesions.

RESULTS

The median NRS pain scores during first and second treatment were 2 (range 0-9) and 4 (0-9), respectively. Lesion clearance rate at 1 year after ambulatory PDT was 84% (21/25 lesions in 22 patients). Of the twenty-three patients treated with both ambulatory and conventional PDT, the median NRS was 1 (0-7) and 5 (1.5-9), respectively, with most patients preferring ambulatory PDT.

CONCLUSION

Ambulatory PDT is effective for superficial non-melanoma skin cancer, with 1 year clearance rates comparative to conventional PDT. Low irradiance ambulatory PDT may be less painful and more convenient than conventional PDT.