INTRODUCTION
Actinic keratosis (AK) is a common intraepithelial atypical proliferation of keratinocytes that clinically develop as small slow-growing scaly or keratotic erythematous patches or papules on chronically sun-exposed areas.1,2
The overall world AK prevalence is 6%–60%, depending on age, gender, predisposing risk factors, and geographical location.2 In Italy, AK prevalence in 7,282 dermatology outpatients has been estimated at 27.4% (34.3% in men and 20.0% in women) with an increase after 40–50 years.3
Clinical severity of individual AKs is commonly assessed according to the Olsen classification system based on AK overall thickness, from Grade 1 (slight palpability) to Grade 2 (moderately thick), and Grade 3 (very thick).4
Regardless of the clinical grade, AK may progress into invasive squamous cell carcinoma (SCC), although the progression rate of AK to SCC is not clearly known and difficult to ascertain.4,5
Sun-exposed skin areas surrounding AKs show subclinical alterations, in terms of gene expression and early molecular and histological changes, similar to those found in AKs. These sun-damaged skin areas are prone to the development of further AK lesions and sun-related skin cancers and are known as field cancerization.6
Due to the lack of prognostic tools to identify individual lesions at risk of progression to invasive SCC, guidelines recommend treating each AK lesion.7 Field-directed treatment is also recommended when more than 5 AKs are present in the field.4
Patients with AKs may complain the overall cosmetic burden of their condition, and today, more and more patients with AKs seek for a concomitant improvement of the visible photoaging signs around the AKs, represented by thicker skin texture, yellow discoloration, dyschromia, coarse wrinkles, telangiectasias, erythema, and sagging skin.8 Therefore, current therapeutic approach to treat AKs and field cancerization may include complementary strategies to improve the overall cosmetic appearance.
The overall world AK prevalence is 6%–60%, depending on age, gender, predisposing risk factors, and geographical location.2 In Italy, AK prevalence in 7,282 dermatology outpatients has been estimated at 27.4% (34.3% in men and 20.0% in women) with an increase after 40–50 years.3
Clinical severity of individual AKs is commonly assessed according to the Olsen classification system based on AK overall thickness, from Grade 1 (slight palpability) to Grade 2 (moderately thick), and Grade 3 (very thick).4
Regardless of the clinical grade, AK may progress into invasive squamous cell carcinoma (SCC), although the progression rate of AK to SCC is not clearly known and difficult to ascertain.4,5
Sun-exposed skin areas surrounding AKs show subclinical alterations, in terms of gene expression and early molecular and histological changes, similar to those found in AKs. These sun-damaged skin areas are prone to the development of further AK lesions and sun-related skin cancers and are known as field cancerization.6
Due to the lack of prognostic tools to identify individual lesions at risk of progression to invasive SCC, guidelines recommend treating each AK lesion.7 Field-directed treatment is also recommended when more than 5 AKs are present in the field.4
Patients with AKs may complain the overall cosmetic burden of their condition, and today, more and more patients with AKs seek for a concomitant improvement of the visible photoaging signs around the AKs, represented by thicker skin texture, yellow discoloration, dyschromia, coarse wrinkles, telangiectasias, erythema, and sagging skin.8 Therefore, current therapeutic approach to treat AKs and field cancerization may include complementary strategies to improve the overall cosmetic appearance.
CASE PRESENTATION
Four patients with multiple AKs (mostly grade 1) and moderate to severe photoaging on face and/or scalp were treated at our clinic, according to an approach based on sequential sessions of photodynamic therapy (PDT) in daylight (DL) to treat AKs and the field cancerization, and injectable non-animal stabilized hyaluronic acid (NASHA®) gel skin boosters (NSBs) to improve the overall skin quality. Patients’ demographic and clinical characteristics are summarized in Table 1.
