Tracking actinic keratosis of face and scalp treated with 0.015% ingenol mebutate to identify clinical and dermoscopic predictors of treatment response

Efficacy evaluation and dermoscopy predictors of photodynamic therapy with different pretreatments in the treatment of actinic keratosis

OBJECTIVE

The aim of this study was to accurately evaluate the efficacy of photodynamic therapy (PDT) on actinic keratosis (AK) in the Asian population and its relationship with preconditioning and dermoscopy grading, and to determine whether some dermoscopic features of AK can independently predict the response to PDT to optimize the choice of clinical treatment.

MATERIALS AND METHODS

From January 2017 to January 2020, patients who were diagnosed as AK with only one lesion in our hospital were included in our study. PDT was performed after pretreatment with ablative fractional CO2 laser or cryotherapy. Logistic regression analysis was used to evaluate the characteristics of dermoscopy to determine the independent predictors of efficacy.

RESULTS

A total of 95 patients were enrolled in the study, and the final clinical evaluation was 92 cases (96.8%) as complete remission and 3 cases (3.2%) as partial remission/no response. Dermoscopy showed complete remission in 77 cases (81.1%) and partial remission/no response in 18 cases (18.9%). No significant difference was observed in the complete remission rate of dermoscopy grade 1 lesion after laser or cryotherapy pretreatment (p > 0.05), but for dermoscopy grade 2 and grade 3 lesions, the complete remission rate (dermoscopy evaluation) of the cryotherapy pretreatment group was higher than that of laser group (p < 0.05). The probability of complete remission with red pseudonetwork at the T0 time point increased by 3.8 times (odds ratio [OR] = 3.870,95%confidence interval [CI]:1.077-13.912, p = 0.048), while the probability of complete response for lesions with slight erosion at the baseline decreased by 85% (OR = 0.150,95%CI:0.033-0.671, p = 0.013).

CONCLUSION

For dermoscopy grade 2 and 3 lesions, PDT after pretreatment with cryotherapy is more effective. Dermoscopy pseudo-reticular structure and microscopic erosions were independent predictors of PDT efficacy. These findings may help clinicians to better select patients with AK for PDT.

Treatment monitoring of 5-fluorouracil 0.5%/salicylic acid 10% lesion-directed therapy for actinic keratosis using dermoscopy and in-vivo reflectance confocal microscopy

Recently, 5-fluorouracil 0.5%/salicylic acid 10% (5-FU/SA) topical solution has been included in the National Italian portfolio for lesion-directed treatment of grade I/II actinic keratosis (AKs) located on the face or scalp. To describe the utility of dermoscopy and RCM in treatment response monitoring of a series of AKs treated with 5-FU/SA as lesion-directed therapy. Consecutive patients were prospectively treated for a maximum of 12 weeks with 5-FU/SA for AKs located on the face or scalp. Clinical, dermoscopic, and confocal images of one index AK were acquired at each visit and pre-specified criteria were evaluated. Clinical, dermoscopic, and confocal responses were evaluated at last follow-up visit. Fourteen patients were enrolled, of which five were treated for 12 weeks, seven for 8, and two for 4 weeks. At a median follow up of 30 weeks, 64.3% (9/14) index AKs achieved complete clinical, 50% (7/14) complete dermoscopic and 42.9% (6/14) complete confocal clearance. Local skin reaction was mild and significantly decreased during therapy administration. Although the small number of cases, our study underlines the utility of both dermoscopy and in-vivo RCM in 5-FU/SA treatment response monitoring for AKs located on the face or scalp.

Field cancerization therapy with ingenol mebutate contributes to restoring skin-metabolism to normal-state in patients with actinic keratosis: a metabolomic analysis

Actinic keratosis (AK) is a skin premalignant lesion, which progresses into squamous cell carcinoma (SCC) if left untreated. Ingenol mebutate gel is approved for local treatment of non-hyperkeratotic, non-hypertrophic AK; it also has the potential to act as a field cancerization therapy to prevent the progression of AK to SCC. To gain better insights into the mechanisms of ingenol mebutate beyond the mere clinical assessment, we investigated, for the first time, the metabolome of skin tissues from patients with AK, before and after ingenol mebutate treatment, with high-resolution magic angle spinning nuclear magnetic resonance spectroscopy. The metabolomic profiles were compared with those of tissues from healthy volunteers. Overall, we identified a number of metabolites, the homeostasis of which became altered during the process of tumorigenesis from healthy skin to AK, and was restored, at least partially, by ingenol mebutate therapy. These metabolites may help to attain a better understanding of keratinocyte metabolism and to unmask the metabolic pathways related to cell proliferation. These results provide helpful information to identify biomarkers with prognostic and therapeutic significance in AK, and suggest that field cancerization therapy with ingenol mebutate may contribute to restore skin metabolism to a normal state in patients with AK.