Actinic Cheilitis: Analysis of Clinical Subtypes, Risk Factors and Associated Signs of Actinic Damage

Efficacy and tolerability of 1.6% phenol-croton peeling vs. topical 5% imiquimod in the treatment of actinic cheilitis: a randomized controlled trial

BACKGROUND

Trials evaluating the effectiveness of topical treatments for actinic cheilitis (AC) are scarce. Despite no comparative data, phenol-croton peeling has been reported as effective in treating this condition.

OBJECTIVE

To assess for the treatment of AC the efficacy and tolerability of a single session of 1.6% phenol-croton peeling vs. topical 5% imiquimod cream applied for 30 days for the treatment of AC.

METHODS

An open, randomized controlled trial was conducted to compare the effectiveness and tolerability of 1.6% phenol-croton peeling vs. topical 5% imiquimod for the treatment of AC [protocol registered at ReBEC (Brazilian Registry of Clinical Trials) - RBR-1044sz68]. Thirty-six patients with biopsy-proven AC were allocated into two groups (1 : 1): the imiquimod group received 5% topical imiquimod three times a week for 30 days, and the croton group underwent one session of 1.6% phenol-croton peeling. The primary outcome was the clearance of AC after 56 days. Secondary outcomes included clinical and histological parameters, adverse effects and clinical results after 180 days.

RESULTS

Complete clinical clearance of AC (defined as clearance of both leukoplakia and hyperkeratosis) at day 56 and day 180 occurred in 17 of 18 (94%) participants from the croton group but in none of the 18 participants in the imiquimod group (P < 0.01). Improvement in all clinical parameters was more prominent in the croton group (P ≤ 0.01). Complete histological normalization at day 56 occurred in 72% of the croton group and only 17% in the imiquimod group (P < 0.01). Histological parameters such as atypia (keratinocyte intraepithelial neoplasia score), solar elastosis and hyperkeratosis reduced in intensity only in the croton group (P < 0.05). Adverse effects were most intense on day 7 in the croton group and persisted until day 21 in the imiquimod group. The study was prematurely terminated at the interim analysis.

CONCLUSIONS

A single session of 1.6% phenol-croton peeling produced clinically and histologically superior results with a shorter recovery period compared with imiquimod for treating AC.

Topical and Intralesional Immunotherapy for the Management of Skin Cancer in Special Locations: Lips and Eyelids

The use of topical and intralesional immunotherapy in the treatment of cutaneous malignant neoplasia in sensitive areas such as the lips and eyelids is discussed. Surgery may not be feasible or may result in deformities in these areas, making alternative treatment options necessary. A narrative literature review was conducted using MEDLINE (PubMed) as the main literature database, collecting available evidence of experiences with various topical and intralesional therapies in the aforementioned anatomical locations, ranging from case reports to clinical trials. The clearance rates and potential adverse reactions of therapeutic options such as imiquimod 5%, 5-fluorouracil (5-FU), photodynamic therapy (PDT), ingenol mebutate (IM), diclofenac, intralesional methotrexate, and interferon are reviewed. Although limited by their heterogeneity and the scarcity of clinical trials, these studies point towards promising response rates and minimal adverse effects, making these treatments viable options in selected cases.

Trends in cutaneous squamous cell carcinoma on the lip incidence and mortality in the United States, 2000-2019

Objective

This study provided a systematic analysis of the trend in incidence and incidence-based mortality for cutaneous squamous cell carcinoma (cSCC) on the lips in the USA using demographic characteristics from the Surveillance, Epidemiology, and End Results (SEER) database.

Methods

Patients diagnosed with cSCC on the lips between 2000 and 2019 from the 17 registries of the USA were identified. Incidence and incidence-based mortality rates were analyzed using SEER*Stat 8.4.0.1 software. This paper calculated incidence rates and incidence-based mortality rates by 100,000 person-years for sex, age, race, SEER registries, median household income ($/year), rural-urban distribution, and primary site. The annual percent changes (APC) in incidence and incidence-based mortality rates were then calculated using joinpoint regression software.

Results

Among 8,625 patients diagnosed with cSCC on the lips from 2000 to 2019, men (74.67%), white (95.21%), and 60-79 years old were the most common population, and 3,869 deaths from cSCC on the lips occurred. The overall incidence of cSCC on the lips was 0.516 per 100,000 person-years. cSCC on the lip incidence rates were highest among men, white, and patients aged 60-79 years old. cSCC on the lip incidence rates decreased by 3.210%/year over the study period. The incidence of cSCC on the lips has been decreasing in all sexes, ages, high- or low-income households, and urban or rural patients. The overall incidence-based mortality rate of cSCC on the lips during 2000-2019 was 0.235 per 100,000 person-years. cSCC on the lip incidence-based mortality rates were highest among men, whites, and people older than 80 years old. cSCC on the lip incidence-based mortality increased by 4.975%/year over the study period. cSCC on the lip incidence-based mortality rates increased for all sexes, races, ages, primary sites, high- or low-income households, and urban or rural patients during the study period.

Conclusion

Among patients in the USA diagnosed with cSCC on the lips from 2000 to 2019, the overall incidence decreased by 3.210% annually, and incidence-based mortality increased by 4.975%/year. These findings update and supplement the epidemiological information of cSCC on the lips in the USA.

Actinic Cheilitis - From Risk Factors to Therapy

Actinic cheilitis or solar cheilosis is considered a precursor of malignancy or even an in situ squamous cell carcinoma (SCC) of the lip, located most frequently on the lower lip. Actinic cheilitis (AC) has a higher likelihood of developing into invasive SCC of the lip, which is one of the deadliest non-melanoma skin cancers. Risk factors include chronic UV exposure, increasing age, male gender, fair phototypes, chronic scarring, immunosuppressive therapy, and tobacco use. From a clinical point of view, AC is characterized by dryness, scaling, atrophy, indistinct borders, and erosions. Ulceration and the appearance of a nodule often suggest the progression to invasive SCC. Dermoscopic examination reveals white structureless areas, scales, erosions, and white halos of the vermilion. Reflectance confocal microscopy shows disruption of the stratum corneum, parakeratosis, an atypical honeycomb pattern, solar elastosis, and dilated and tortuous blood vessels with increased blood flow. The rate of malignant transformation ranges from 10 to 30% and early diagnoses and treatment are essential in preventing the development of invasive SCC. Optimal treatment has not been established yet, but invasive and topical treatments can be tried. The present paper aims to review the existing data regarding epidemiology, risk factors, clinical picture, non-invasive imaging, diagnosis, and therapy in AC.

Combination of Laser Therapy and Photodynamic Therapy with 5-Aminolevulinic Acid Patch for the Treatment of Actinic Cheilitis

Background: Actinic cheilitis (AC) is a premalignant lesion of the lips that can evolve into squamous cell carcinoma. Among nonsurgical treatments, photodynamic therapy (PDT) with 5-aminolevulinic acid (ALA) patch might represent a new noninvasive therapeutic approach for AC. Objective: We sought to investigate the potential role of fractional CO₂ laser pretreatment in boosting ALA penetration and distribution into AC treated with PDT. Methods: We report a case of a woman with AC on the lower lip, treated with ablative fractional CO₂ laser to boost drug delivery of 5-ALA patch before PDT treatment. Reflectance confocal microscopy was performed to assess diagnosis and treatment response. Results: We detected a good clinical and cosmetic outcome after two applications of combined treatment. Erythema, crust, and edema were reported as side effects. Conclusions: This case report shows that ablative fractional CO₂ laser-assisted PDT might be an effective therapeutic alternative for patients with AC who refuse or are contraindicated for surgical procedures.

Sun protection as a protective factor for actinic cheilitis: Cross-sectional population-based study

OBJECTIVE

To determine whether sun protection is associated with lower occurrence of actinic cheilitis in adults living in a city from southern Brazil.

MATERIALS AND METHODS

A multi-stage proportional sample of 404 individuals 18 years and older was obtained. Interviews and clinical examinations were conducted in participants' households. Four categories of self-reported use of sun protection were determined. Multivariable Poisson regression was used to assess the associations.

RESULTS

Prevalence of actinic cheilitis was 47.1%. In the first main-effects multivariable model, AC was significantly associated with sex, age, skin colour and duration of sun exposure, but not with sun protection. However, the association between sun protection and actinic cheilitis was modified by the time of sun exposure. Among those exposed ≥4 hr/day to sun, individuals using physical protection or physical + chemical protection were 33% (prevalence ratio = 0.67, 95% confidence interval [CI] 0.47-0.94, p = .02) and 36% (PR = 0.64, 95% CI 0.47-0.94, p = .02), respectively, less likely to have actinic cheilitis than those who did not use any sun protection, adjusting for sex, age and skin colour.

CONCLUSIONS

Physical and chemical sun protection were associated with lower occurrence of actinic cheilitis in individuals with greater exposure to sun.