A follow-up study of recurrence and cosmesis in completely responding superficial and nodular basal cell carcinomas treated with methyl 5-aminolaevulinate-based photodynamic therapy alone and with prior curettage

Evaluation of Device-Based Cutaneous Channels Using Optical Coherence Tomography: Impact for Topical Drug Delivery

BACKGROUND

Topical medications play a large role in the management of cutaneous diseases, but penetration is limited. Device-assisted drug delivery using mechanical destruction, lasers, and other energy-based modalities can increase penetration and absorption through creation of transcutaneous channels.

OBJECTIVE

To examine real-time, in vivo cutaneous changes in response to various devices used to improve topical drug delivery through optical coherence tomography (OCT) imaging.

METHODS AND MATERIALS

Treatment was performed with 8 medical devices, including mechanical destruction, lasers, and other energy-based modalities. Optical coherence tomography was used for real-time, noninvasive, in vivo imaging.

RESULTS

Using OCT, microneedling and radiofrequency microneedling demonstrated no cutaneous channels. Both low-energy, low-density, fractional nonablative lasers produced transient channels, which closed within hours. The fractional nonablative 1,927-nm thulium fiber and 1,550-nm erbium fiber lasers created channels with epidermal debris within, which were still closing at 24 hours. The fractional thermomechanical ablative device and the fractional ablative CO2 laser produced channels that were still open at 24 hours. CO2 laser channels had thick rims of coagulated tissue and remained open for longer.

CONCLUSION

Demonstrable differences among the devices were seen, and only some can produce observable channels, the characteristics of which vary with each technology.

Efficacy and safety of HpD-PDT for Extramammary Paget's Disease refractory to conventional therapy: A prospective, open-label and single arm pilot study

BACKGROUND

Extramammary Paget's Disease (EMPD) is an intraepithelial cancer that is prone to recurrence and sometimes refractory to therapy. A few EMPD cases have been treated with Photodynamic therapy (PDT), which reported high complete remission (CR) rates and low recurrence with hematoporphyrin derivatives (HpD) The aim of this study was to further explore the efficacy and safety of HpD-PDT for EMPD patients.

METHODS

Open-label, single arm, pilot study was designed to investigate the role of HpD-PDT in EMPD. The HpD sensitizer was given intravenously at a dose of 3 or 5 mg/kg 48 h before light irradiation with a laser 630 nm red light at a dose level of 150-200 J/cm². Clinical parameters involving gender, age, disease course, previous treatment, tumor thickness, long diameter of lesion, TNM staging, EMPD staging, HpD dosage, Visual Analogue Scale (VAS) score, 1st month visit result, subsequent treatment, follow up period and endpoint outcomes were collected to evaluate efficacy and safety of the intervention.

RESULTS

Eleven patients with pathologic confirmed EMPD were treated with HpD-PDT. The thickness of skin lesions which were located in vulva, penis, scrotum, and perianal area is 0.8∼6.7 mm (mean thickness 2.9 mm). All patients were followed up for an average of 17.4 months (12∼27 months). Complete remission (CR) rate and partial remission (PR) rate at the 1st month were 90.1% (10/11) and 9.1% (1/11) respectively. At the end of follow-up, 72.7% of the subjects (8/11) showed CR. Pain, infection, photosensitivity and uroschesis are recorded as adverse events (AEs) in this population, and no event of hepatic impairment was reported. After treatment, all the eleven patients showed different degrees of scar in the treatment site, but none of them had any structural or functional abnormalities.

CONCLUSIONS

According to our study, HpD-PDT in EMPD is able to offer acceptable disease outcomes including relatively high CR rate, with good cosmetic and functional outcomes, and could be considered a potential recommended therapy for patients with EMPD.

TRIAL REGISTRATION

Chinese Clinical Trial Register (ChiCTR-1900024965).

A Skin Cancer Prophylaxis Study in Hairless Mice Using Methylene Blue, Riboflavin, and Methyl Aminolevulinate as Photosensitizing Agents in Photodynamic Therapy

The high incidence of sunlight-induced human skin cancers reveals a need for more effective photosensitizing agents. In this study, we compared the efficacy of prophylactic photodynamic therapy (PDT) when methylene blue (MB), riboflavin (RF), or methyl aminolevulinate (MAL) were used as photosensitizers. All mice in four groups of female C3.Cg/TifBomTac hairless immunocompetent mice (N = 100) were irradiated with three standard erythema doses of solar-simulated ultraviolet radiation (UVR) thrice weekly. Three groups received 2 × 2 prophylactic PDT treatments (days 45 + 52 and 90 + 97). The PDT treatments consisted of topical administration of 16% MAL, 20% MB, or 20% RF, and subsequent illumination that matched the photosensitizers’ absorption spectra. Control mice received no PDT. We recorded when the first, second, and third skin tumors developed. The pattern of tumor development after MB-PDT or RF-PDT was similar to that observed in irradiated control mice (p > 0.05). However, the median times until the first, second, and third skin tumors developed in mice given MAL-PDT were significantly delayed, compared with control mice (256, 265, and 272 vs. 215, 222, and 230 days, respectively; p < 0.001). Only MAL-PDT was an effective prophylactic treatment against UVR-induced skin tumors in hairless mice.

Sequential Treatment of Superficial Basal Cell Carcinomas With Topical Methyl Aminolevulinate Photodynamic Therapy and Imiquimod 5% Cream: A Retrospective Study of Clinical and Cosmetic Outcomes

BACKGROUND

Topical photodynamic therapy (PDT) and imiquimod 5% (IMQ) cream are established treatments for superficial basal cell carcinoma (sBCC). Both have high initial response rates and recurrence rates of up to 37%. Recent studies demonstrate that PDT and imiquimod may act on sBCCs via synergistic immunomodulatory pathways.

OBJECTIVE

To describe the sequential use of MAL-PDT and imiquimod 5% cream in the treatment of sBCCs and report treatment tolerability, cosmetic outcomes, and efficacy.

MATERIALS AND METHODS

This is a retrospective case series of patients presenting over a 2-year period with primary sBCC who underwent 2 cycles of topical MAL-PDT, followed by 6 weeks of imiquimod 5% cream. Outcome measures were resolution of the index lesion at 3 months, side effects, cosmetic outcome, and long-term recurrence (LTR).

RESULTS

A total of 17 consecutive patients (n = 17) with a combined 21 sBCCs (n = 21) were included. The median length of follow-up was 72 months (range 24-95 months). Long-term recurrence occurred in 2/21 lesions (10%).

CONCLUSION

Sequential use of PDT and imiquimod was well tolerated with good cosmetic outcomes. The 10% LTR rate is at the lower end of the range reported for single modality treatment; however, larger samples are required to evaluate efficacy differences.

[Surgical techniques in the treatment of basal cell carcinoma-a prospective investigation]

Hintergrund

Basalzellkarzinome sind die häufigsten epithelialen Hauttumoren und eine häufige Indikation für dermatologische Eingriffe. Trotz der Etablierung medikamentöser Therapieoptionen stellt die Operation weiterhin die Therapie der Wahl dar. Hierbei stehen verschiedene Möglichkeiten zur Verfügung, die von der Kürettage bis hin zu komplexen dermatochirurgischen Eingriffen reichen. Neben dem Hauptaspekt der geringen lokalen Rezidivraten sind auch ästhetische Faktoren und die Anzahl der Eingriffe für die Wahl der Therapie wichtig.

Methoden

In dieser Studie wurden 347 Patienten mit 398 Basalzellkarzinomen (nodulärer Typ, Durchmesser bis 10 mm) prospektiv untersucht. Die Patienten wurden randomisiert in 2 Behandlungsarme eingeteilt: In einer Gruppe wurden die Tumoren kürettiert, in der anderen Gruppe exzidiert. Als Kontrolle dienten Patienten, die im gleichen Untersuchungszeitraum 3‑D-histologisch kontrolliert operiert wurden.

Ergebnisse

Die höchste lokale Rezidivrate wurde nach der Kürettage (14,0 %) beobachtet, während die Gruppe mit 3‑D-Histologie die niedrigste Rezidivrate (0,9 %; p < 0,001) aufwies. In der 3‑D-Gruppe waren mehr Re-Exzisionen erforderlich, um eine vollständige Entfernung des Tumors zu erreichen, als in der Gruppe mit histologischen Serienschnitten. Die Patienten bewerteten das ästhetische Ergebnis am besten nach der Kürettage. Die mittlere Nachbeobachtungszeit betrug 3,9 Jahre.

Schlussfolgerung

Die Wahl der chirurgischen Therapie bei kleinen nodulären Basalzellkarzinomen hängt von den individuellen Gegebenheiten ab. 3‑D-histologisch kontrollierte Exzisionen mit Wundverschluss nach vollständiger Tumorentfernung zeigten in unserer Studie die geringste Rezidivrate. Aber auch die Kürettage stellt eine mögliche chirurgische Therapieoption mit minimalem Aufwand und einer akzeptablen Rezidivrate dar, die zu guten ästhetischen Ergebnissen führen kann.

Nanoparticles for topical drug delivery: Potential for skin cancer treatment

Nanoparticles offer new opportunities for the treatment of skin diseases. The barrier function of the skin poses a significant challenge for nanoparticles to permeate into the tissue, although the barrier is partially compromised in case of injury or inflammation, as in the case of skin cancer. This may facilitate the penetration of nanoparticles. Extensive research has gone into developing nanoparticles for topical delivery; however, relatively little progress has been made in translating them to the clinic for treating skin cancers. We summarize the types of skin cancers and practices in current clinical management. The review provides a comprehensive outlook of the various nanoparticle technologies tested for topical therapy of skin cancers and summarizes the obstacles that impede its progress from the bench-to-bedside. The review also aims to provide an understanding of the pathways that govern nanoparticle penetration into the skin and a critical analysis of the approaches used to study nanoparticle interactions within the tissue.

Overall Results for a National Program of Photodynamic Therapy for Basal Cell Carcinoma: A Multicenter Clinical Study to Bring New Techniques to Social Health Care

Along the past years, a national program to implement photodynamic therapy (PDT) for nonmelanoma skin cancer (NMSC) was performed over the Brazilian territory. Using a strategy involving companies, national bank, and medical partners, equipment, medication, and protocols were tested in a multicenter study. With results collected over 6 years, we could reach a great deal of advances concerning the use of PDT for skin cancer. We present the overall reached results of the program and discuss several aspects about it, including public politics of treatment. A discussion about advantages of this technique within conditions of health care is placed, comparing PDT with surgery, including an analysis about the implementation of PDT in countries in development as Brazil, considering not only technical but social aspects, as the distribution of medical doctor in the Brazilian territory. The program resulted in a huge dissemination of PDT in Brazil and many countries in Latin America, in a partnership among public politics, universities, companies, and hospitals and clinics and in the insertion of national technologies as option to treat NMSC. Consequence of the program is mainly the continuation of the use of PDT in Brazil and many countries in Latin America.

Photodynamic therapy for skin cancer: How to enhance drug penetration?

Photodynamic therapy (PDT) induced by protoporphyrin IX (PpIX) has been widely used in dermatological practices such as treatment of skin cancers. Clearance rate depends on different factors such as light irradiation, skin oxygenation and drug penetration. The poor penetration of 5-aminolevulinic acid (5-ALA) with topical application is limited and restrains the production of PpIX which could restrict PDT outcomes. This review will focus on techniques already used to enhance drug penetration in human skin, and will present their results, advantages, and drawbacks. Chemical and physical pretreatments will be discussed. Chemical pre-treatments comprise of drug formulation modification, use of agents that modify the heme cycle, enhance PpIX formation, and the combination of differentiation-promoting agent prior to PDT. On the other hand, physical pretreatments affect the skin barrier by creating holes in the skin or by removing stratum corneum. To promote drug penetration, iontophoresis and temperature modulation are interesting alternative methods. Cellular mechanisms enrolled during chemical or physical pretreatments have been investigated in order to understand how 5-ALA penetrates the skin, why it is preferentially metabolized in PpIX in tumour cells, and how it could be accumulated in deeper skin layers. The objective of this review is to compare clinical trials that use innovative technology to conventional PDT treatment. Most of these pretreatments present good or even better clinical outcomes than usual PDT.

Biomarkers of basal cell carcinoma resistance to methyl-aminolevulinate photodynamic therapy

Background

Methyl-aminolevulinate photodynamic therapy (MAL-PDT) is an excellent option for the treatment of basal cell carcinoma (BCC). However, up to 25% of cases are resistant to this treatment modality.

Objective

The aim of this study was to identify potential biomarkers of BCC response to MAL-PDT.

Material and methods

Clinical, histological, and immunohistochemical (p53, Ki-67, CD-31, COX2, β-catenin, EGFR, and survivin) variables were analyzed in a retrospective study of consecutive BCC patients treated with MAL-PDT at the San Jorge Hospital, Huesca, Spain between January 2006 and December 2015. To deepen on these markers, the effects on p53 and cyclin D1 expression, in vitro response to MAL-PDT of 2 murine BCC cell lines (ASZ and BSZ), was also evaluated.

Results

The retrospective study examined the response to MAL-PDT of 390 BCCs from 182 patients. The overall clinical response rate was 82.8%, with a mean follow-up time of 35.96 months (SD = 23.46). Immunohistochemistry revealed positive p53 in 84.6% of responders but only 15.4% of nonresponsive tumors (p = 0.011). Tumors with increased peripheral palisading of basal cell islands to immunostaining β-catenin responded poorly to PDT (p = 0.01). In line with our findings in patients, in vitro studies revealed a better response to PDT in the p53-positive ASZ cell line than the p53-negative BSZ cell line (p<0.01).

Multivariate analysis revealed that the following variables were significantly associated with response to PDT: age, nBCC, presence of peritumoral inflammatory infiltrate, and p53 immunopositivity. Patients with positive p53 immunostaining were 68.54 times more likely to achieve cure than p53-negative patients (CI95% 2.94–159.8)

Conclusion

Our finding suggest that certain clinicopathological and immunohistochemical variables, particularly p53 expression, may serve as indicators of BCC response to MAL-PDT, and thus facilitate the selection of patients who are most likely to benefit from this therapy.

Beyond the margins: real-time detection of cancer using targeted fluorophores

Over the past two decades, synergistic innovations in imaging technology have resulted in a revolution in which a range of biomedical applications are now benefiting from fluorescence imaging. Specifically, advances in fluorophore chemistry and imaging hardware, and the identification of targetable biomarkers have now positioned intraoperative fluorescence as a highly specific real-time detection modality for surgeons in oncology. In particular, the deeper tissue penetration and limited autofluorescence of near-infrared (NIR) fluorescence imaging improves the translational potential of this modality over visible-light fluorescence imaging. Rapid developments in fluorophores with improved characteristics, detection instrumentation, and targeting strategies led to the clinical testing in the early 2010s of the first targeted NIR fluorophores for intraoperative cancer detection. The foundations for the advances that underline this technology continue to be nurtured by the multidisciplinary collaboration of chemists, biologists, engineers, and clinicians. In this Review, we highlight the latest developments in NIR fluorophores, cancer-targeting strategies, and detection instrumentation for intraoperative cancer detection, and consider the unique challenges associated with their effective application in clinical settings.

Usefulness of Photodynamic Therapy as a Possible Therapeutic Alternative in the Treatment of Basal Cell Carcinoma

Basal cell carcinoma (BCC) is the most common cancer in individuals with fair skin type (I–II) and steadily increasing in incidence (70% of skin malignancy). It is locally invasive but metastasis is usually very rare, with an estimated incidence of 0.0028%–0.55%. Conventional therapy is surgery, especially for the H region of the face and infiltrative lesions; in case of inoperable tumors, radiotherapy is a valid option. Recently, topical photodynamic therapy (PDT) has become an effective treatment in the management of superficial and small nodular BCC. PDT is a minimally invasive procedure that involves the administration of a photo-sensibilizing agent followed by irradiation at a pre-defined wavelength; this determines the creation of reactive oxygen species that specifically destroy target cells. The only major side effect is pain, reported by some patients during the irradiation. The high cure rate and excellent cosmetic outcome requires considering this possibility for the management of patients with both sporadic and hereditary BCC. In this article, an extensive review of the recent literature was made, in order to clarify the role of PDT as a possible alternative therapeutic option in the treatment of BCC.

Assessment of ALA-induced PpIX production in porcine skin pretreated with microneedles

Photodynamic therapy (PDT) is used for skin treatments of premalignant and cancer lesions and recognized as a non-invasive technique that combines tissue photosensitization and subsequent exposure to light to induce cell death. However, it is limited to the treatment of superficial lesions, mainly due to the low cream penetration. Therefore, the improvement of transdermal distribution of aminolevulinic acid (ALA) is needed. In this study, the kinetics and homogeneity of production of ALA-induced PpIX after the skin pre-treatment with microneedles rollers of 0.5, 1.0 and 1.5 mm length were investigated. An improvement in homogeneity and production of PpIX was shown in a porcine model. Widefield fluorescence imaging three hours after the topical application of ALA-cream in the combined treatment with microeedles rollers.

Photodynamic Therapy Followed by Mohs Micrographic Surgery Compared to Mohs Micrographic Surgery Alone for the Treatment of Basal Cell Carcinoma: Results of a Pilot Single-Blinded Randomised Controlled Trial

Introduction:

Basal cell carcinoma is a common cutaneous malignant tumour. Surgical excision is the “gold standard” treatment for most subtypes, with Mohs micrographic surgery (MMS) offering the highest cure rate. Other treatment modalities used include photodynamic therapy (PDT).

Background:

We aimed to study the efficacy of combining MMS with PDT to see whether this would reduce the number of stages and final defect size when compared with MMS alone.

Materials and Methods:

Our study was a single-centre, single-blinded, randomised and controlled pilot study involving a total of 19 patients. Nine patients were randomised to pre-treatment with PDT followed by MMS of whom two withdrew; the remaining 10 patients were randomised to the MMS alone. Follow-up visits were arranged at 3 and 6 months post-surgery.

Results:

In the PDT arm, five out of the seven treated patients (71%) had their initial tumour size decreased following PDT treatment prior to MMS. The average number of stages in the PDT arm was 1.85, compared to 2.5 in the MMS arm. The average number of sections in the PDT arm was 4.2, in comparison to 5.2 in the MMS arm.

Conclusion:

Our pilot study showed a promising but limited role for PDT as an adjunct in MMS in the treatment of selected cases of basal cell carcinomas. Larger trials, preferably multi-centred are required to further examine the role of this combination therapy.

Photodynamic therapy with methyl aminolevulinate in the treatment of basal cell carcinoma

The article presents the results of the studies on the effectiveness of treatment basal cell carcinoma of the skin with photodynamic therapy with 5-aminolevulinic acid and methyl aminolevulinate. The results of the comparing trials between photodynamic therapy with methyl aminolevulinate and different other treatment modalities are presented.

The dermatoscopic universe of basal cell carcinoma

Following the first descriptions of the dermatoscopic pattern of basal cell carcinoma (BCC) that go back to the very early years of dermatoscopy, the list of dermatoscopic criteria associated with BCC has been several times updated and renewed. Up to date, dermatoscopy has been shown to enhance BCC detection, by facilitating its discrimination from other skin tumors and inflammatory skin diseases. Furthermore, upcoming evidence suggests that the method is also useful for the management of the tumor, since it provides valuable information about the histopathologic subtype, the presence of clinically undetectable pigmentation, the expansion of the tumor beyond clinically visible margins and the response to non-ablative treatments. In the current article, we provide a summary of the traditional and latest knowledge on the value of dermatoscopy for the diagnosis and management of BCC.

Photodynamic Therapy with 5% δ-Aminolevulinic Acid is Safe and Effective Treatment of Acne Vulgaris in Japanese Patients

BACKGROUND AND AIMS

Photodynamic therapy with aminolevulinic acid (ALA-PDT) is effective therapy for acne vulgaris; however, relatively strong side effects limit its wide usage. We have previously demonstrated that ALA-induced protoporphyrin IX distribution with lower concentrations and shorter contact time of ALA resulted in focused damage in sebaceous glands in vivo. We have formulated a protocol for ALA-PDT using 5% ALA with 2 hours contact time. The objective of this study was to establish the effectiveness and side effect profile of the new protocol in humans.

SUBJECTS AND METHODS

Eleven Japanese patients (Fitzpatrick's skin type III - IV, mean age 23.7±7.2) with facial acne received topical application of 5% ALA for 2 hours with subsequent illumination by a broadband light (600 - 1100 nm, 15J/cm(2), 60 mW/cm(2)). Subjects were evaluated prior to the procedure, 1 month, and 3 months after the treatment by a blinded dermatologist using the global acne grading system (GAGS). Side effects were monitored through the treatment period.

RESULTS

The mean GAGS score decreased from 22.1±3.8 at baseline to 19.4 at 1 month, and to 16.3 at 3 months after PDT (P<0.05). Ten of eleven patients experienced local side effects, such as erythema, which were of minimal to mild severity. However, most side effects were of minimal to mild severity, and all of them resolved within several days without post inflammatory hyper pigmentation.

CONCLUSION

Our protocol was effective for acne in Japanese and did not exhibit severe side effects.

Non-melanoma skin cancers: photodynamic therapy, cryotherapy, 5-fluorouracil, imiquimod, diclofenac, or what? Facts and controversies

Surgical modalities-excision, Mohs micrographic surgery, and electrodesiccation with curettage-are the preferred treatments for nonmelanoma skin cancer (NMSC). When used within guidelines, they have cure rates greater than 90%. Despite this, many other treatments have been studied and utilized for NMSC. We present a comprehensive review of the literature on these topical treatments. Photodynamic therapy (PDT) is administered under numerous and significantly varied regimens, and there are a wide range of cure rates reported. Even with aggressive regimens, PDT is not as effective as surgery is, and it is not a first-line therapy for NMSC. The cryotherapy regimen aggressive enough to adequately treat NMSC carries adverse effects and cosmetic outcomes poor enough to negate its usefulness. Topical 5-fluorouracil and imiquimod are efficacious and safe for the treatment of superficial basal cell carcinoma (BCC) but not other BCC subtypes or squamous cell carcinoma. They are self-administered twice daily for several weeks; therefore, patient and tumor selection are vital to ensuring adherence. There are currently insufficient data to support the use of topical diclofenac and ingenol mebutate for NMSC.

Current evidence and applications of photodynamic therapy in dermatology

In photodynamic therapy (PDT) a photosensitizer – a molecule that is activated by light – is administered and exposed to a light source. This leads both to destruction of cells targeted by the particular type of photosensitizer, and immunomodulation. Given the ease with which photosensitizers and light can be delivered to the skin, it should come as no surprise that PDT is an increasingly utilized therapeutic in dermatology. PDT is used commonly to treat precancerous cells, sun-damaged skin, and acne. It has reportedly also been used to treat other conditions including inflammatory disorders and cutaneous infections. This review discusses the principles behind how PDT is used in dermatology, as well as evidence for current applications of PDT.

Photodynamic therapy with topical aminolevulinic acid

Photodynamic therapy (PDT) is a relatively new therapy in dermatology that uses the topical application of a porphyrin derivative to selectively destroy a cutaneous target. The action is implemented by the application of a specific light frequency. The ability of porphyrin to selectively target tumor tissue has been known since the 1960s. In the late 1970s, the underlying mechanism was defined, and Dougherty’s discovery of the first chromophore led to the production and commercialization of Photofrin^®. Many other chromophores that can act as photosensitizers have been studied since then, with aminolevulinic acid currently the most commonly used chromophore in clinical practice. PDT is simple, minimally invasive and can be administered on an outpatient basis. The efficacy of PDT has been proven for actinic keratosis, Bowen’s disease and basal cell carcinoma; another of its well-known applications is the treatment of photoaging. Indications for its use are continuously increasing, and promising results are reported for various skin diseases. In this paper we report the mechanism of action of PDT with aminolevulinic acid, the literature concerning the most common diseases treated with PDT and the subsequent level of evidence.

Laser assisted drug delivery: a review of an evolving technology

BACKGROUND

Topically applied drugs have a relatively low cutaneous bioavailability.

OBJECTIVE

This article reviews the existing applications of laser assisted drug delivery, a means by which the permeation of topically applied agents can be enhanced into the skin.

RESULTS

The existing literature suggests that lasers are a safe and effective means of enhancing the delivery of topically applied agents through the skin. The types of lasers most commonly studied in regards to drug delivery are the carbon dioxide (CO2 ) and erbium:yttrium-aluminum-garnet (Er:YAG) lasers. Both conventional ablative and fractional ablative modalities have been utilized and are summarized herein.

LIMITATIONS

The majority of the existing studies on laser assisted drug delivery have been performed on animal models and additional human studies are needed.

CONCLUSIONS

Laser assisted drug delivery is an evolving technology with potentially broad clinical applications. Multiple studies demonstrate that laser pretreatment of the skin can increase the permeability and depth of penetration of topically applied drug molecules for both local cutaneous and systemic applications.

Low-dose angiostatic tyrosine kinase inhibitors improve photodynamic therapy for cancer: lack of vascular normalization

Photodynamic therapy (PDT) is an effective clinical treatment for a number of different cancers. PDT can induce hypoxia and inflammation, pro-angiogenic side effects, which may counteract its angio-occlusive mechanism. The combination of PDT with anti-angiogenic drugs offers a possibility for improved anti-tumour outcome. We used two tumour models to test the effects of the clinically approved angiostatic tyrosine kinase inhibitors sunitinib, sorafenib and axitinib in combination with PDT, and compared these results with the effects of bevacizumab, the anti-VEGF antibody, for the improvement of PDT. Best results were obtained from the combination of PDT and low-dose axitinib or sorafenib. Molecular analysis by PCR revealed that PDT in combination with axitinib suppressed VEGFR-2 expression in tumour vasculature. Treatment with bevacizumab, although effective as monotherapy, did not improve PDT outcome. In order to test for tumour vessel normalization effects, axitinib was also applied prior to PDT. The absence of improved PDT outcome in these experiments, as well as the lack of increased oxygenation in axitinib-treated tumours, suggests that vascular normalization did not occur. The current data imply that there is a future for certain anti-angiogenic agents to further improve the efficacy of photodynamic anti-cancer therapy.

Photodynamic therapy in dermatology: current concepts in the treatment of skin cancer

Photodynamic therapy is a treatment modality that is developing rapidly and increasing in utilization within various medical specialties, including dermatology. This technique requires the presence of a photosensitizer, light energy and molecular oxygen to selectively destroy pathologic cells. A thorough understanding of photobiology and tissue optics is necessary to correctly and effectively utilize photodynamic therapy in dermatology. Photodynamic therapy has been approved by the US Food and Drug Administration to treat actinic keratoses. In Europe, photodynamic therapy is currently being used in the treatment of actinic keratoses and basal cell carcinoma. Other off-label uses of photodynamic therapy have included cutaneous lesions of Bowen's disease, psoriasis, cutaneous T-cell lymphoma and acne. Most recently, photodynamic therapy has been employed in photorejuvenation. The advantages of photodynamic therapy include the capacity for noninvasive targeted therapy via topical application of the drug and local irradiation of involved areas, as well as the ability to generate excellent cosmetic results with minimal discomfort. This review summarizes the fundamentals of photodynamic therapy and its role in the treatment of cutaneous disorders, particularly skin malignancies.

Aminolevulinic acid photodynamic therapy: medical evidence for its expanded use

Photodynamic therapy (PDT) has gained much popularity over the past several years as clinicians and researchers have expanded upon its indications and how one should utilize PDT in everyday practice. PDT is not a new field within dermatology or medicine in general, but for all practical reasons, PDT is considered to still be in its infancy. This article will review the history of PDT, explore PDT in both the US and European market place, and show how PDT is best utilized today in the USA. Finally, future ideas/thoughts on where PDT is heading will be surmised.

Update on non-melanoma skin cancer and the value of dermoscopy in its diagnosis and treatment monitoring

Dermoscopy has become an integrative part of the clinical examination of skin tumors. This is because it significantly improves the early diagnosis of melanoma and non-melanoma skin cancer (NMSC) including basal cell carcinoma and keratinocyte skin cancer compared with the unaided eye. Besides its value in the noninvasive diagnosis of skin cancer, dermoscopy has also gained increased interest in the management of NMSC. Dermoscopy has been used in the preoperative evaluation of tumor margins, monitoring of the outcomes of topical treatments and post-treatment follow-up. This article provides an update on NMSC with special emphasis on dermoscopy in the diagnosis and management of basal cell carcinoma, actinic keratosis, Bowens' disease and squamous cell carcinoma.

Thickness of superficial basal cell carcinoma (sBCC) predicts imiquimod efficacy: a proposal for a thickness-based definition of sBCC

BACKGROUND

Basal cell carcinoma (BCC) is the most common malignancy in the white population. It is an important driver of healthcare costs and causes significant morbidity. Topical imiquimod is a good noninvasive treatment alternative for surgical excision in superficial BCC (sBCC). However, there are currently no uniform histological definitions of sBCC. A definition based on tumour thickness might be a good alternative.

OBJECTIVES

To determine whether tumour thickness in sBCC is a predictor of treatment failure.

METHODS

We retrospectively examined 127 histological biopsy specimens of sBCC treated primarily with imiquimod five times a week for 6 weeks. Mean follow-up was 34 months (range 3-91). Recurrence was evaluated clinically with histological verification.

RESULTS

Among nonrecurrent cases the median tumour thickness was 0·26 mm (range 0·09-0·61), while for recurrent cases the median tumour thickness was 0·57 mm (range 0·41-1·41, P < 0·0001). Among lesions ≤ 0·40 mm in thickness, none recurred, whereas for lesions > 0·40 mm the recurrence rate was 58% (P < 0·0001).

CONCLUSIONS

We recommend the use of tumour thickness to define the superficial pattern in pathology reports for BCC as this can help to determine treatment response of sBCC to imiquimod.

Reflectance confocal microscopy allows in vivo real-time noninvasive assessment of the outcome of methyl aminolaevulinate photodynamic therapy of basal cell carcinoma

BACKGROUND

Photodynamic therapy (PDT) with methyl aminolaevulinate (MAL) is an approved noninvasive treatment option for basal cell carcinoma (BCC). In vivo reflectance confocal microscopy (RCM) is a noninvasive imaging technique that has proved useful for in vivo real-time cytomorphological analysis of BCC cells infiltrating the epidermis.

OBJECTIVES

  To investigate the use of in vivo RCM to assess the persistence of BCC cells surviving MAL-PDT.

METHODS

In vivo  RCM images of 20 biopsy-proven BCCs were taken before patients underwent a treatment cycle with MAL-PDT. Follow-up after 3months was performed using clinical examination, RCM and conventional dermoscopy. Treated areas also underwent a targeted 3-mm punch biopsy for standard haematoxylin and eosin histology stain to establish the clinical and instrumental correlation of the treatment outcome.

RESULTS

  Three months after PDT, clinical examination established that two out of 20 BCCs were persistent; dermoscopy found three out of 20 residual BCCs, but RCM showed that one of these lesions was a false positive, and showed persistent BCC foci in five out of 20 lesions. Histological analysis of targeted biopsies confirmed these results.

CONCLUSIONS

  RCM provided noninvasive, early detection of incipient recurrences of BCC after MAL-PDT. RCM findings steered targeted biopsies and surgical removal, or a new MAL-PDT, of these subclinical recurrences with minimal invasiveness.

Use of photodynamic therapy for treatment of actinic keratoses in organ transplant recipients

Solid organ transplant recipients are predisposed to actinic keratoses (AK) and nonmelanoma skin cancers, owing to the lifelong immunosuppression required. Today, increasing numbers of organ transplants are being performed and organ transplant recipients (OTRs) are surviving much longer. Photodynamic therapy (PDT) is proving a highly effective treatment modality for AK amongst this susceptible group of patients. Following an overview of the pathogenesis of AK amongst OTRs, the authors review current safety and efficacy data and how this relates to the role of PDT for the treatment of AK in OTRs.

Photodynamic therapy using topical 5-aminolaevulinic acid vs. surgery for basal cell carcinoma

BACKGROUND

Photodynamic therapy (PDT) is an attractive modality for the treatment of BCC, based on its generally favorable efficacy, adverse effect profile and its excellent cosmetic outcome.

OBJECTIVES

The purpose of the study is to compare the efficacy and cosmetic outcome of photodynamic therapy with topical 5-aminolaevulinic acid (ALA-PDT) vs. simple excision surgery for superficial and nodular basal cell carcinoma (BCC).

METHODS

A total of 72 patients, 32 with 48 lesions, were treated with ALA- PDT, and 40 with 46 lesions treated by excision were included in this prospective, comparative, controlled, clinical study. The patients have been followed for 16-37 months (mean 25 months). The PDT was performed in combination with 5-aminolaevulinic acid twice, one month apart. Surgical excision was performed under local anesthesia with a 3-mm margin, followed by histological examination. The cosmetic outcome was evaluated by the physician according to a 4-point scale.

RESULTS

Overall 94 BCC were treated. Complete healing rates did not differ significantly between groups, P = 0.64 (46/48 [95.83%] lesions treated with PDT vs. 44/46 [95.65%] lesions with surgery). In the first 12 months of follow-up, 4 lesions had recurred, 2 of which were in the PDT group while 2 lesions after surgery. The mean follow-up was 25 months. The recurrence rate in the ALA-PDT group was 4.16% vs. 4.34% in the surgery group, p = 0.64. The cosmetic outcome was superior for ALA-PDT at all time points. At 12 months, 100% lesions treated with ALA-PDT had an excellent or good cosmetic outcome, according to the investigator, compared with 88.86% with surgery, P = 0.01.

CONCLUSION

ALA-PDT offers a similarly high efficacy, and a better cosmetic outcome than simple excision surgery in the treatment of BCC.

Pre-treatment deep curettage can significantly reduce tumour thickness in thick Basal cell carcinoma while maintaining a favourable cosmetic outcome when used in combination with topical photodynamic therapy

Topical photodynamic therapy (PDT) has limitations in the treatment of thick skin tumours. The aim of the study was to evaluate the effect of pre-PDT deep curettage on tumour thickness in thick (≥2 mm) basal cell carcinoma (BCC). Additionally, 3-month treatment outcome and change of tumour thickness from diagnosis to treatment were investigated. At diagnosis, mean tumour thickness was 2.3 mm (range 2.0–4.0). Pre- and post-curettage biopsies were taken from each tumour prior to PDT. Of 32 verified BCCs, tumour thickness was reduced by 50% after deep curettage (P ≤ 0.001). Mean tumour thickness was also reduced from diagnosis to treatment. At 3-month followup, complete tumour response was found in 93% and the cosmetic outcome was rated excellent or good in 100% of cases. In conclusion, deep curettage significantly reduces BCC thickness and may with topical PDT provide a favourable clinical and cosmetic short-term outcome.

Do lasers or topicals really work for nonmelanoma skin cancers?

Novel strategies are urgently needed to address the millions of nonmelanoma skin cancers treated in the United States annually. The need is greatest for those patients who are poor surgical candidates or those prone to numerous nonmelanoma skin cancers and therefore at risk for marked disfigurement. Traditional treatment strategies include electrosurgery with curettage, radiation therapy, cryotherapy, excision, and Mohs micrographic surgery. Alternatives to traditional treatment, including topical medications and light or laser therapies, are becoming popular; however, there are various degrees of efficacy among these alternative tactics. These alternatives include topical retinoids, peels, 5-fluorouracil, imiquimod, photodynamic therapy, and lasers. The purpose of this paper is to review the available data regarding these alternative strategies and permit the reader to have a sense of which therapies are reasonable options for care.

Nonsurgical treatment of nonmelanoma skin cancer

The ever-increasing incidence of primary cutaneous malignancies has heralded the need for multiple treatment options. Surgical modalities remain the mainstay of treatment of nonmelanoma skin cancer. However, it is important for the dermatologic surgeon to have an understanding of all treatment options to assist the patient in making the most informed decision possible, ultimately leading to the most favorable outcome. This article explores the available nonsurgical treatment options, their indications, and their efficacy.

Recent advances in the prevention and treatment of skin cancer using photodynamic therapy

Photodynamic therapy (PDT) is a noninvasive procedure that involves a photosensitizing drug and its subsequent activation by light to produce reactive oxygen species that specifically destroy target cells. Recently, PDT has been widely used in treating non-melanoma skin malignancies, the most common cancer in the USA, with superior cosmetic outcomes compared with conventional therapies. The topical 'photosensitizers' commonly used are 5-aminolevulinic acid (ALA) and its esterified derivative methyl 5-aminolevulinate, which are precursors of the endogenous photosensitizer protoporphyrin IX. After treatment with ALA or methyl 5-aminolevulinate, protoporphyrin IX preferentially accumulates in the lesion area of various skin diseases, which allows not only PDT treatment but also fluorescence diagnosis with ALA-induced porphyrins. Susceptible lesions include various forms of non-melanoma skin cancer such as actinic keratosis, basal cell carcinoma and squamous cell carcinoma. The most recent and promising developments in PDT include the discovery of new photosensitizers, the exploitation of new drug delivery systems and the combination of other modalities, which will all contribute to increasing PDT therapeutic efficacy and improving outcome. This article summarizes the main principles of PDT and its current clinical use in the management of non-melanoma skin cancers, as well as recent developments and possible future research directions.

Nonsurgical treatment options for Basal cell carcinoma

Basal cell carcinoma (BCC) remains the most common form of nonmelanoma skin cancer (NMSC) in Caucasians, with perhaps as many as 2 million new cases expected to occur in the United States in 2010. Many treatment options, including surgical interventions and nonsurgical alternatives, have been utilized to treat BCC. In this paper, two non-surgical options, imiquimod therapy and photodynamic therapy (PDT), will be discussed. Both modalities have demonstrated acceptable disease control rates, cosmetically superior outcomes, and short-term cost-effectiveness. Further studies evaluating long-term cure rates and long-term cost effectiveness of imiquimod therapy and PDT are needed.