The natural history of actinic keratosis: a systematic review

Knowledge about the development of untreated actinic keratosis (AK) and risk of progression into squamous cell carcinoma (SCC) is important. Therefore, we set out to synthesize primary data on the natural history of AK. We carried out a systematic literature search (Medline, Medline in Process, Embase, Cochrane) of studies on the natural course of AK, regarding (i) progression and regression rates per lesion-year, (ii) changes in total lesion counts over time, and (iii) spontaneous field regression and recurrence rates, taking into account studies on participants without immunosuppression and history of skin cancer, immunosuppressed patients and participants with a history of skin cancer and sunscreen use. Twenty-four eligible studies were identified providing data on at least one of the outcomes. Progression rates of AK to SCC ranged from 0% to 0·075% per lesion-year, with a risk of up to 0·53% per lesion in patients with prior history of nonmelanoma skin cancer. Rates of regression of single lesions ranged between 15% and 63% after 1 year. The data available on recurrence rates of single lesions 1 year after regression indicate a recurrence rate of 15-53%. Data on the relative change of total AK count over time are heterogeneous, and range from -53% to +99·1%. Spontaneous complete field regression rates range from 0% to 21%, with recurrences in 57%. In general, the available data are limited. Important methodological limitations apply. Currently, no reliable estimates concerning the frequency of AK developing into invasive carcinoma can be given, and further studies are needed.

Efficacy of systemic therapies for moderate-to-severe psoriasis: a systematic review and meta-analysis of long-term treatment

BACKGROUND

Despite the chronicity of psoriasis, most systematic reviews focus on short-term treatment.

METHODS

The systematic search strategy and results from the German Psoriasis Guidelines were adapted. To update the data a literature search in Medline, Embase and the Cochrane Library was conducted. The proportion of participants achieving ≥75% decrease in Psoriasis Area and Severity Index (PASI) as well as Dermatology Life Quality Index (DLQI) reduction at different time points were assessed. Trials were summarized with respect to time periods and study designs. Suitable trials were included in a meta-analysis. Particular attention was paid to statistical approaches of handling dropouts.

RESULTS

A total of 33 articles including 27 trials totaling 6575 patients with active treatment were included in the systematic review. Seven randomized controlled trials were eligible for the meta-analysis. Over a 24 week treatment period infliximab [risk difference (RD) 78%, 95% confidence interval (CI) 72-83%] and ustekinumab 90 mg every 12 weeks (RD 77%, 95% CI 71-83%) were the most efficacious treatments. Adalimumab (RD: 60%, 95% CI 45-74%) showed results within the range of different etanercept dosages (etanercept 50 mg once weekly: RD 62%, 95% CI, 52-72%), (etanercept 25 mg twice weekly: RD 45%, 95% CI 34-56%), (etanercept 50 mg twice weekly: RD 56%, 95% CI 49-62%) and (etanercept 50 mg twice weekly until week 12, then 25 mg twice weekly: RD 50%, 95% CI 42-57%). After 24 weeks a decrease in efficacy for inflximab, adalimumab and etanercept was observed.

CONCLUSIONS

More sufficient data is required to draw reliable conclusions in extended long-term treatment and head-to-head comparisons are necessary.