Effects of topical 0.8% piroxicam and 50+ sunscreen filters on actinic keratosis in hypertensive patients treated with or without photosensitizing diuretic drugs: an observational cohort study

Abstract

Background: Photosensitizing diuretics use (especially thiazide compounds) is associated with a significantly higher risk of squamous cell carcinoma (SCC). Actinic keratosis (AK) is a precursor of SCC.

Study aim: To evaluate in a prospective cohort study the efficacy of topical piroxicam 0.8% and sunscreen 50+ (ACTX) in the treatment of AK in hypertensive subjects with or without TD treatment.

Subjects and methods: A total of 119 hypertensive subjects with multiple AK (39 under chronic TD treatment; and 80 treated with other non-TD, non-photosensitizing antihypertensive drugs) were enrolled after their informed consent in a 6-month observational cohort study. All the subjects were treated with ACTX twice daily. The primary endpoint was the evolution of AK lesions at baseline, after 3 and 6 months. The secondary endpoint was the clearance of AK target lesions and field of cancerization by dermoscopic evaluation using a score evaluating erythema, scaling, pigmentation, and follicular plugs (ESPFP score; ranging from 0 to 20). An investigator, unaware of the type of antihypertensive treatments (TD or non-TD), performed all the clinical and dermoscopy evaluations.

Results: At baseline, AK mean (SD) lesion number in TD group was 14.1(4) and 14.6(4) in the non-TD group. ESPFP mean (SD) score at baseline was 5.8(1.2) in both groups. A significant reduction of AK lesions in comparison with baseline was observed in both groups. A statistically significant greater reduction was observed in TD in comparison with the non-TD group (-54% vs -32%). ESPFP score was reduced in a higher proportion in the TD group in comparison with the non-TD group (-60% vs -37%, respectively). ACTX treatment was very well tolerated.

Conclusion: In hypertensive subjects with multiple AK, the topical use of ACTX is associated with a significant reduction of lesions count with an improvement in the field cancerization. The clinical efficacy is more pronounced in subjects under thiazide diuretics treatment.

Keywords: actinic keratosis; piroxicam; skin cancer; thiazide diuretics.

Figure 1

Evolution of AK lesion count in subjects under treatment with TD drugs and in subjects not under treatment with TD drugs, at baseline and after three and six months of ACTX treatment. Notes: *P<0.001 vs baseline; ^#P<0.05 vs Non-TD group. Abbreviations: ACTX, 0.8% piroxicam and sunscreen 50+; AK, actinic keratosis; TD, thiazide diuretic.

Figure 2

Evolution of dermoscopy severity ESPFP score of a target lesion in subject under treatment with TD drugs and in subjects no under treatment with TD drugs at baseline and after six months of ACTX treatment. Notes: *P<0.005 vs baseline; ^#P<0.05 vs Non-TD group. Abbreviations: ACTX, 0.8% piroxicam and sunscreen 50+; ESPFP, erythema, scaling, pigmentation, and follicular plugs; TD, thiazide diuretic.