Influence of Serum Vitamin D Level in the Response of Actinic Keratosis to Photodynamic Therapy with Methylaminolevulinate

Diagnosis and therapy of actinic keratosis

Actinic keratosis (AK) is considered a chronic and recurring in situ skin neoplasia, with a possible transformation into invasive squamous cell carcinoma (SCC). Among others, predominant risk factors for development of AK are UV-light exposure and immunosuppression. Basal epidermal keratinocyte atypia (AK I) and proliferation (PRO score) seem to drive malignant transformation, rather than clinical appearance of AK (Olsen I-III). Due to the invasiveness of punch biopsy, those histological criteria are not regularly assessed. Non-invasive imaging techniques, such as optical coherence tomography (OCT), reflectance confocal microscopy (RCM) and line-field confocal OCT (LC-OCT) are helpful to distinguish complex cases of AK, Bowen's disease, and SCC. Moreover, LC-OCT can visualize the epidermis and the papillary dermis at cellular resolution, allowing real-time PRO score assessment. The decision-making for implementation of therapy is still based on clinical risk factors, ranging from lesion- to field-targeted and ablative to non-ablative regimens, but in approximately 85% of the cases a recurrence of AK can be observed after a 1-year follow-up. The possible beneficial use of imaging techniques for a non-invasive follow-up of AK to detect recurrence or invasive progression early on should be subject to critical evaluation in further studies.

Diagnose und Therapie aktinischer Keratosen

Actinic keratosis (AK) is considered a chronic and recurring in situ skin neoplasia, with a possible transformation into invasive squamous cell carcinoma (SCC). Among others, predominant risk factors for development of AK are UV-light exposure and immunosuppression. Basal epidermal keratinocyte atypia (AK I) and proliferation (PRO Score) seem to drive malignant turnover, rather than clinical appearance of AK (Olsen I-III). Due to the invasiveness of punch biopsy, those histological criteria are not regularly assessed. Non-invasive imaging techniques, such as optical coherence tomography (OCT), reflectance confocal microscopy (RCM) and line-field confocal OCT (LC-OCT) are helpful to distinguish complex cases of AK, Bowen's disease and SCC. Moreover, LC-OCT can visualize the epidermis and the papillary dermis at cellular resolution, allowing real-time PRO Score assessment. The decision-making for implementation of therapy is still based on clinical risk factors, ranging from lesion- to field-targeted and ablative to non-ablative regimes, but in approximately 85% of the cases a recurrence of AK can be observed after a 1-year follow-up. The possible beneficial use of imaging techniques for a non-invasive follow-up of AK to detect recurrence or invasive progression early on should be subject to critical evaluation in further studies.

Treatment of nonmelanoma skin cancer with pro-differentiation agents and photodynamic therapy: Preclinical and clinical studies (Review)

Photodynamic therapy (PDT) is a nonscarring cancer treatment in which a pro-drug (5-aminolevulinic acid, ALA) is applied, converted into a photosensitizer (protoporphyrin IX, PpIX) which is then activated by visible light. ALA-PDT is now popular for treating nonmelanoma skin cancer (NMSC), but can be ineffective for larger skin tumors, mainly due to inadequate production of PpIX. Work over the past two decades has shown that differentiation-promoting agents, including methotrexate (MTX), 5-fluorouracil (5FU) and vitamin D (Vit D) can be combined with ALA-PDT as neoadjuvants to promote tumor-specific accumulation of PpIX, enhance tumor-selective cell death, and improve therapeutic outcome. In this review, we provide a historical perspective of how the combinations of differentiation-promoting agents with PDT (cPDT) evolved, including Initial discoveries, biochemical and molecular mechanisms, and clinical translation for the treatment of NMSCs. For added context, we also compare the differentiation-promoting neoadjuvants with some other clinical PDT combinations such as surgery, laser ablation, iron-chelating agents (CP94), and immunomodulators that do not induce differentiation. Although this review focuses mainly on the application of cPDT for NMSCs, the concepts and findings described here may be more broadly applicable towards improving the therapeutic outcomes of PDT treatment for other types of cancers.

Significant Association of Poly-A and Fok1 Polymorphic Alleles of the Vitamin D Receptor with Vitamin D Serum Levels and Incidence of Squamous Cutaneous Neoplasia

Vitamin D3, a prohormone, is converted to circulating calcidiol and then to calcitriol, the hormone that binds to the vitamin D receptor (VDR) (a nuclear transcription factor). Polymorphic genetic sequence variants of the VDR are associated with an increased risk of breast cancer and melanoma. However, the relationship between VDR allelic variants and the risk of squamous cell carcinoma and actinic keratosis remains unclear. We examined the associations between two VDR polymorphic sites, Fok1 and Poly-A, and serum calcidiol levels, actinic keratosis lesion incidence, and the history of cutaneous squamous cell carcinoma in 137 serially enrolled patients. By evaluating the Fok1 (F) and (f) alleles and the Poly-A long (L) and short (S) alleles together, a strong association between genotypes FFSS or FfSS and high calcidiol serum levels (50.0 ng/ml) was found; conversely, ffLL patients showed very low calcidiol levels (29.1 ng/ml). Interestingly, the FFSS and FfSS genotypes were also associated with reduced actinic keratosis incidence. For Poly-A, additive modeling showed that Poly-A (L) is a risk allele for squamous cell carcinoma, with an OR of 1.55 per copy of the L allele. We conclude that actinic keratosis and squamous cell carcinoma should be added to the list of squamous neoplasias that are differentially regulated by the VDR Poly-A allele.

A Review of MAL-PDT for the Treatment Strategy of Actinic Keratosis: Broader Clinical Perspectives Beyond the Data and Guideline Recommendations

Methyl aminolevulinate (MAL) is a topical compound approved for use with photodynamic therapy (PDT) for the treatment of actinic keratosis (AK) and field cancerization in certain countries. There exists a high burden of disease for patients with AK: repeated treatments are required, there is a known risk of progression to keratinocyte carcinoma, and cosmetic appearance is affected. Delivery of PDT using MAL is a flexible treatment strategy available in many forms; red light, daylight, or artificial daylight can be used for illumination, all of which result in high AK clearance rates and low recurrence. MAL-PDT protocols continue to evolve to further improve adherence and treatment outcomes. Here, we used PubMed to search MEDLINE to identify guidelines, consensus recommendations, and studies describing the use of MAL for the treatment of AK. The aim of this targeted review is to consider various MAL-PDT treatment strategies on the basis of published literature, with a focus on personalizing treatment for the heterogeneous AK population.

Regular use of vitamin D supplement is associated with fewer melanoma cases compared to non-use: a cross-sectional study in 498 adult subjects at risk of skin cancers

There are conflicting results on the role of vitamin D system in cutaneous carcinogenesis. Therefore, it was investigated whether the use of oral vitamin D supplements associates with photoaging, actinic keratoses, pigment cell nevi, and skin cancers. In this cross-sectional study, 498 adults (aged 21-79 years, 253 males, 245 females, 96 with immunosuppression) subjects at risk of any type of skin cancer were examined, and possible confounding factors were evaluated. The subjects were divided into three groups based on their self-reported use of oral vitamin D supplements: non-use, occasional use, or regular use. The serum level of 25-hydroxyvitamin-D3 was analyzed in 260 subjects. In 402 immunocompetent subjects, vitamin D use did not associate with photoaging, actinic keratoses, nevi, basal, and squamous cell carcinoma. In contrast, there were lower percentages of subjects with a history of past or present melanoma (32/177, 18.1% versus 32/99, 32.3%, P  = 0.021) or any type of skin cancer (110/177, 62.1% versus 74/99, 74.7%, P  = 0.027) among regular users compared to non-users. In the logistic regression analysis, the odds ratio for melanoma was 0.447 ( P  = 0.016, 95% confidence interval, 0.231-0.862) among regular users. Furthermore, the investigator-estimated risk class of skin cancers was significantly lower among regular users. Serum 25-hydroxyvitamin-D3 did not show marked associations with skin-related parameters. The results on 96 immunosuppressed subjects were somewhat similar, although the number of subjects was low. In conclusion, regular use of vitamin D associates with fewer melanoma cases, when compared to non-use, but the causality between them is obscure.

Influence of serum vitamin D level in the response of actinic keratosis to ingenol mebutate

Vitamin D (VD) serum levels, and keratinocytic basal expression of vitamin D receptor (VDR) before treatment of actinic keratoses (AK) have been previously reported as possible biomarkers of the response of AK to treatments. We intended to evaluate the association between these and other serum and immunohistochemical parameters with the response of AK to treatment with topical ingenol mebutate (IM). Twenty-five patients with AK on the head were treated with topical IM 0.015% gel once daily for 3 days. Biopsies were taken at baseline and 6 weeks after treatment. Immunohistochemical staining was performed for VDR, P53, Ki67, Aurora B, Survivin and β-catenin. Basal serum 25(OH)D levels were determined. IM was more effective for KIN I and II AKs than in KIN III, and histological responders showed significantly higher serum VD levels (30.278 [SD 8.839] ng/mL) than nonresponders (21.14 [SD 7.079] ng/mL, p = 0.023). In addition, mean basal expression of VDR (45.63 [SD 16.105] %) increased significantly (57.92 [SD 14.738] %, p = 0.003) after treatment with IM. A significant decrease after treatment in the expression of several markers of aggressiveness and progression to squamous cell carcinoma, namely P53, Ki-67, aurora B kinase and survivin, was also observed. Our results support a relationship between VD status and the response of AK to treatment with topical IM, suggesting that its previous correction to proper serum levels in VD-deficient patients could improve the response of AK to the treatment.

Vitamin D and Vitamin D3 Supplementation during Photodynamic Therapy: A Review

Photodynamic therapy is an unconventional yet increasingly common method of treating dermatological diseases and cancer that is implemented more often in adults than in children. Current clinical uses include treatment of actinic keratosis, superficial basal cell carcinomas, and acne. Despite its high efficiency, photodynamic therapy support supplements have recently been reported in the literature, including calcitriol (1,25-dihydroxycholecalciferol), the active form of vitamin D, and vitamin D3 cholecalciferol. In clinical trials, photodynamic therapy enhanced with vitamin D or D3 supplementation has been reported for treatment of squamous cell skin cancers, actinic keratosis, and psoriasis. Experimental research on the effect of photodynamic therapy with vitamin D or D3 has also been carried out in breast cancer cell lines and in animal models. The aim of this review is to evaluate the usefulness and effectiveness of vitamin D and D3 as supports for photodynamic therapy. For this purpose, the Pubmed and Scopus literature databases were searched. The search keyword was: “vitamin D in photodynamic therapy”. In the analyzed articles (1979–2022), the authors found experimental evidence of a positive effect of vitamin D and D3 when used in conjunction with photodynamic therapy. An average of 6–30% (in one case, up to 10 times) increased response to photodynamic therapy was reported in combination with vitamin D and D3 as compared to photodynamic therapy alone. Implementing vitamin D and D3 as a supplement to photodynamic therapy is promising and may lead to further clinical trials and new clinical methodologies.

Combination-Based Strategies for the Treatment of Actinic Keratoses with Photodynamic Therapy: An Evidence-Based Review

Photodynamic therapy (PDT) is a highly effective and widely adopted treatment strategy for many skin diseases, particularly for multiple actinic keratoses (AKs). However, PDT is ineffective in some cases, especially if AKs occur in the acral part of the body. Several methods to improve the efficacy of PDT without significantly increasing the risks of side effects have been proposed. In this study, we reviewed the combination-based PDT treatments described in the literature for treating AKs; both post-treatment and pretreatment were considered including topical (i.e., diclofenac, imiquimod, adapalene, 5-fluorouracil, and calcitriol), systemic (i.e., acitretin, methotrexate, and polypodium leucotomos), and mechanical–physical (i.e., radiofrequency, thermomechanical fractional injury, microneedling, microdermabrasion, and laser) treatment strategies. Topical pretreatments with imiquimod, adapalene, 5-fluorouracil, and calcipotriol were more successful than PDT alone in treating AKs, while the effect of diclofenac gel was less clear. Both mechanical laser treatment with CO2 and Er:YAG (Erbium:Yttrium–Aluminum–Garnet) as well as systemic treatment with Polypodium leucotomos were also effective. Different approaches were relatively more effective in particular situations such as in immunosuppressed patients, AKs in the extremities, or thicker AKs. Conclusions: Several studies showed that a combination-based approach enhanced the effectiveness of PDT. However, more studies are needed to further understand the effectiveness of combination therapy in clinical practice and to investigate the role of acitretin, methotrexate, vitamin D, thermomechanical fractional injury, and microdermabrasion in humans.

Vitamin D and Vitamin D Analogs as Adjuncts to Field Therapy Treatments for Actinic Keratoses: Current Research and Future Approaches

Actinic keratoses (AK), also known as solar keratoses, are precancerous hyperkeratotic papules caused by long-term exposure to ultraviolet radiation. Management of AK prior to progression to cutaneous malignancy represents an important window of intervention. This is important on a population level, given the high incidence, morbidity, financial costs, and the low but measurable risk of mortality from cutaneous neoplasia. Treatments for AK have been refined for many years with significant progress over the past decade. Those recent advancements lead to questions about current treatment paradigms and the role of harnessing the immune system in field therapies. Recent studies suggest a key interplay between vitamin D and cancer immunity; in particular, the systemic and/or topical vitamin D analogs can augment field therapies used for severe actinic damage. In this review, we will examine the literature supporting the use of vitamin D-directed therapies to improve field therapy approaches. An enhanced understanding of these recent concepts with a focus on mechanisms is important in the optimized management of AK. These mechanisms will be critical in guiding whether selected populations, including those with immunosuppression, heritable cancer syndromes, and other risk factors for skin cancer, can benefit from these new concepts with vitamin D analogs and whether the approaches will be as effective in these populations as in immunocompetent patients.

Sequential treatment with calcitriol and methyl aminolevulinate-daylight photodynamic therapy for patients with multiple actinic keratoses of the upper extremities

BACKGROUND

Topical photodynamic therapy (PDT) is a widely used and effective treatment for actinic keratoses (AKs). However, cure rates are significantly reduced for AKs on acral sites. We compared the sequential regimen of topical calcitriol and methyl aminolevulinate (MAL) daylight-PDT (CAL-DL-PDT) versus placebo and MAL-DL-PDT (P-DL-PDT) on acral AKs in an intra-individual, randomized trial.

METHODS

Adult patients with multiple all grade AKs of the upper extremities were treated with daily topical calcitriol or placebo for 14 days followed by 2 sessions of DL-MAL-PDT. After 3 months, patients were evaluated for lesion response rate, both overall and by AK grade, and patient ≥ 75 % clearance rate. Safety assessments included pain VAS immediately after the first DL-PDT session, side effects after calcitriol pretreatment and 7 days after the first DL-PDT session. Cosmetic outcome by the physician and patient's preference were graded at the end of the study.

RESULTS

Forty-two patients were enrolled and 36/42 completed the study. After 3 months, the overall lesion response rate and patient ≥ 75 % clearance rate of CAL-DL-PDT were higher, albeit not significantly, than P-DL-PDT. According to grade, response rate of grouped AK II/III was significantly higher for CAL-DL-PDT than for P-DL-PDT while similar results were observed for grade I AKs. Mild erythema and itch were reported after calcitriol application. No significant difference was observed in pain intensity. Local skin reactions occurred more frequently on the CAL-DL-PDT-treated sides. Cosmetic outcome did not differ but overall subject's preference was slightly significantly in favor of P-DL-PDT.

CONCLUSIONS

CAL-DL-PDT is more effective than P-DL-PDT for thicker "difficult to treat" AKs on the upper extremities but is associated with increased local skin reactions.