Evaluation of Bowen disease by in vivo reflectance confocal microscopy

Photodynamic Therapy for the Treatment of Bowen's Disease: A Review on Efficacy, Non-Invasive Treatment Monitoring, Tolerability, and Cosmetic Outcome

Bowen's disease represents the in situ form of cutaneous squamous cell carcinoma; although it has an excellent prognosis, 3-5% of lesions progress to invasive cutaneous squamous cell carcinoma, with a higher risk in immunocompromised patients. Treatment is therefore always necessary, and conventional photodynamic therapy is a first-line option. The aim of this review is to provide an overview of the clinical response, recurrence rates, safety, and cosmetic outcome of photodynamic therapy in the treatment of Bowen's disease, considering different protocols in terms of photosensitizers, light source, and combination treatments. Photodynamic therapy is a valuable option for tumors at sites where wound healing is poor/delayed, in the case of multiple and/or large tumors, and where surgery would be difficult or invasive. Dermoscopy and reflectance confocal microscopy can be used as valuable tools for monitoring the therapeutic response. The treatment is generally well tolerated, with mild side effects, and is associated with a good/excellent cosmetic outcome. Periodic follow-up after photodynamic therapy is essential because of the risk of recurrence and progression to cSCC. As the incidence of keratinocyte tumors increases, the therapeutic space for photodynamic therapy will further increase.

[Translated article] Reflectance Confocal Microscopy Terminology in Spanish: A Delphi Consensus Study

The terminology used to describe reflectance confocal microscopy (RCM) findings in both melanocytic and nonmelanocytic lesions has been standardized in English. We convened a panel of Spanish-speaking RCM experts and used the Delphi method to seek consensus on which Spanish terms best describe RCM findings in this setting. The experts agreed on 52 terms: 28 for melanocytic lesions and 24 for nonmelanocytic lesions. The resulting terminology will facilitate homogenization, leading to a better understanding of structures, more standardized descriptions in clinical registries, and easier interpretation of clinical reports exchanged between dermatologists.

Reflectance Confocal Microscopy Terminology in Spanish: A Delphi Consensus Study

The terminology used to describe reflectance confocal microscopy (RCM) findings in both melanocytic and nonmelanocytic lesions has been standardized in English. We convened a panel of Spanish-speaking RCM experts and used the Delphi method to seek consensus on which Spanish terms best describe RCM findings in this setting. The experts agreed on 52 terms: 28 for melanocytic lesions and 24 for nonmelanocytic lesions. The resulting terminology will facilitate homogenization, leading to a better understanding of structures, more standardized descriptions in clinical registries, and easier interpretation of clinical reports exchanged between dermatologists.

Superficial basal cell carcinoma mimicking Bowen's disease: Diagnosis with noninvasive imaging

BACKGROUND

Superficial basal cell carcinoma (SBCC) is the rare subtype of basal cell carcinoma (BCC). BCC occurs in exposed areas such as the head and face, SCBB prone to form in trunk. Due to the manifestation of erythema and desquamation, it is prone to misdiagnosed as Bowen's disease in clinica.

MATERIALS AND METHODS

A 68-year-old female presented with coin-sized erythema located on the lower abdomen for 5 years. Histopathological examination was performed, and results informed the diagnosis of SBCC. Lesions were detected by dermoscopy, reflectance confocal microscopy (RCM) and multiphoton microscopy (MPM).

RESULTS

Dermoscopy revealed yellow-red background with more dendritic and linear proliferating vessels and more blue-gray nonaggregated dots structures. RCM displayed streaming of stratum spinosum, tortuous dilated vessels, highlighted inflammatory cells, and medium refraction round and oval tumor cell masses. MPM showed epidermal cells in polar arrangement, increased cell spacing, disorganized stratum granulosum and elastic fibers are gathered in clusters.

CONCLUSION

We described a case of SBCC detected by dermoscopy, RCM and MPM. Noninvasive imaging features may provide a potentially tools in recognition and differentiation of SBCC.

Non-Melanoma Skin Cancer Clearance after Medical Treatment Detected with Noninvasive Skin Imaging: A Systematic Review and Meta-Analysis

Simple Summary

Non-melanoma skin cancers (NMSC) represent about one-third of all malignancies. While surgery is the current gold standard treatment, many nonsurgical approaches are available for selected cases. Currently, there are no studies concerning the overall impact of dermoscopy, optical coherence tomography (OCT) and reflectance confocal microscopy (RCM) for NMSC treatment monitoring. Therefore, we aim to review the current literature and provide an updated summary of noninvasive skin imaging in NMSC medical treatment management and the diagnostic accuracy of the most advanced technologies.

Abstract

Background/Objectives: Non-melanoma skin cancer (NMSC) treated with nonsurgical therapies can be monitored with noninvasive skin imaging. The precision of dermoscopy, reflectance confocal microscopy (RCM) and optical coherence tomography (OCT) in detecting clearance is unclear. We aim to report the proportion of persisting tumors identified with noninvasive technologies available in the literature. Methods: A systematic literature search was conducted on the PubMed and Cochrane Public Library Databases for articles published prior to November 2021. Statistical analyses were conducted with MedCalc 14.8.1 software. Results: A total of eight studies (352 lesions) reporting noninvasive imaging for NMSC clearance following nonsurgical treatment were included. Most (n = 7) reported basal cell carcinoma (BCC), and one study reported squamous cell carcinoma (SCC) clearance. A meta-analysis of the BCC clearance revealed that the summary effect for RCM was higher, as compared to the other techniques. Interestingly, the sensitivity and specificity for OCT were 86.4% (95% CI: 65.1–97.1) and 100% (95% CI: 94.8–100.0), respectively, whilst, for RCM, they reached 100% (95%CI: 86.8–100) and 72.5% (95% CI: 64.4–79.7), respectively. Conclusions: Routine clinical examination and dermoscopy underperform when employed for NMSC clearance monitoring, although they represent the first approach to the patient. OCT and RCM seem to improve the detection of persistent BCC after medical treatment.

Diagnosing of primary cutaneous amyloidosis using dermoscopy and reflectance confocal microscopy

BACKGROUND

Primary cutaneous amyloidosis (PCA) is apruritic and potentially disfiguring disorder; this disease is usually diagnosed clinically due to its common occurrence. However, for cases with atypical presentations or for those physicians not familiar with PCA, the diagnosis can be a challenge.

OBJECTIVE

To observe the characteristics of PCA under dermoscopy and reflectance confocal microscopy (RCM) in order to gain experience and reference for clinicians to facilitate diagnosis.

METHODS

The typical lesions of 110 patients with primary cutaneous amyloidosis were observed by dermoscopy and RCM, and scanning results were recorded. Thirty patients followed by complete excision for histopathological analysis.

RESULTS

A total of 110 patients with clinically diagnosed PCA were enrolled. Forty-seven patients had lesions consistent with macular amyloidosis and 63 with lichen amyloidosus. The dermoscopic findings of PCA shared a common feature, each 'macule' was composed of a central hub pattern surrounded by brownish pigmentation, The pattern of the central hub could be brown, white, scar-like and structureless area. RCM features of total patients consisted of dermal papilla present cloud-like agglomerate which are high refractive index.

CONCLUSIONS

Dermoscopy and reflectance confocal microscopy can be used in the diagnosis of PCA, which can provide a basis for doctors to diagnose.

Clinical Applications of In Vivo and Ex Vivo Confocal Microscopy

Confocal laser scanning microscopy (CLSM) has been introduced in clinical settings as a tool enabling a quasi-histologic view of a given tissue, without performing a biopsy. It has been applied to many fields of medicine mainly to the skin and to the analysis of skin cancers for both in vivo and ex vivo CLSM. In vivo CLSM involves reflectance mode, which is based on refractive index of cell structures serving as endogenous chromophores, reaching a depth of exploration of 200 μm. It has been proven to increase the diagnostic accuracy of skin cancers, both melanoma and non-melanoma. While histopathologic examination is the gold standard for diagnosis, in vivo CLSM alone and in addition to dermoscopy, contributes to the reduction of the number of excised lesions to exclude a melanoma, and to improve margin recognition in lentigo maligna, enabling tissue sparing for excisions. Ex vivo CLSM can be performed in reflectance and fluorescent mode. Fluorescence confocal microscopy is applied for “real-time” pathological examination of freshly excised specimens for diagnostic purposes and for the evaluation of margin clearance after excision in Mohs surgery. Further prospective interventional studies using CLSM might contribute to increase the knowledge about its application, reproducing real-life settings.

Reflectance Confocal Microscopy of Pigmented Bowen's Disease: A Case Series of Difficult to Diagnose Lesions

Pigmented Bowen's disease is a rare variant of in situ squamous skin cell carcinoma. It mainly affects patients between 60 and 70 years of age. Its clinical features include well-demarcated, pigmented plaque arising in photo-exposed areas of the body. The best-characterized feature of the disease by histological examination is the presence of atypical keratinocytes, hyperpigmentation of the epidermis with trans-epidermal elimination of melanin and dermal melanophages. Precise diagnosis is often difficult, both clinically and dermoscopically, as Bowen's disease is often mistaken with keratinocyte tumors such as solar lentigines, seborrheic keratosis, Bowenoid papulosis, pigmented basal cell carcinoma, pigmented actinic keratosis; or even melanocytic lesions such as melanocytic nevus, pigmented epithelioid melanocytoma, and melanoma. Precise diagnosis often requires biopsy and histopathological examination of the tissue. Reflectance confocal microscopy is a noninvasive technique to diagnose pigmented skin lesions. To date, not much data are available regarding its use in the diagnosis of pigmented Bowen's disease. Herein, we report a well-represented case series of pigmented Bowen's disease imaged using dermoscopy and reflectance confocal microscopy.

Reflectance confocal microscopy for noninvasive examination of nonmelanocytic tumors and virus-associated skin lesions in organ transplant recipients

BACKGROUND

Drug-induced immunosuppression is necessary to prevent rejection of the foreign organ in transplanted patients, but neoplastic and virus-associated skin diseases are frequent complications. Reflectance confocal microscopy (RCM) recently emerged as a promising tool for the early diagnosis of skin lesions.

MATERIALS AND METHODS

A total of 61 skin lesions, among them 20 basal cell carcinomas, six Bowen's diseases, 23 actinic keratoses, and 12 verrucae, were analyzed. All lesions were clinically evaluated followed by RCM evaluation by two independent dermatologists and histological examination.

RESULTS

For the diagnosis of basal cell carcinoma, a sensitivity of 100% by both investigators (INV I + II) and a specificity of 100% by INV I and 80% by INV II were achieved. The sensitivity average rate for RCM features reached by both investigators ranged between 60% and 100%, and the specificity between 55% and 90%. For the diagnosis of actinic keratosis, a concordant sensitivity of 94.4% and a specificity of 80% (INV I) and 60% (INV II) were detected. The sensitivity average rate of specific RCM criteria ranged between 72.3% and 97.2%, whereas specificity ranged between 20% and 90%. Regarding verrucae, RCM confirmed the histological diagnosis with a sensitivity of 85.7% (INV I) and 100% (INV II), while specificity was 100% and 80%, respectively.

CONCLUSION

Reflectance confocal microscopy resulted to be a reliable tool for the noninvasive diagnosis of neoplastic and virus-associated skin changes in organ transplant recipients. Nevertheless, given the frequency and diagnostic complexity of the hyperkeratotic lesions occurring post-transplantation, larger cohorts of patients are required to confirm and consolidate these findings.

Skin Imaging Using Ultrasound Imaging, Optical Coherence Tomography, Confocal Microscopy, and Two-Photon Microscopy in Cutaneous Oncology

With the recognition of dermoscopy as a new medical technology and its available fee assessment in Korea comes an increased interest in imaging-based dermatological diagnosis. For the dermatologist, who treats benign tumors and malignant skin cancers, imaging-based evaluations can assist with determining the surgical method and future follow-up plans. The identification of the tumor's location and the existence of blood vessels can guide safe treatment and enable the use of minimal incisions. The recent development of high-resolution microscopy based on laser reflection has enabled observation of the skin at the cellular level. Despite the limitation of a shallow imaging depth, non-invasive light-based histopathologic examinations are being investigated as a rapid and pain-free process that would be appreciated by patients and feature reduced time from consultation to treatment. In the United States, the current procedural terminology billing code was established for reflectance confocal microscopy in 2016 and has been used for the skin cancer diagnosis ever since. In this review, we introduce the basic concepts and images of ultrasound imaging, optical coherence tomography, confocal microscopy, and two-photon microscopy and discuss how they can be utilized in the field of dermatological oncology.

Non-invasive imaging techniques for the in vivo diagnosis of Bowen's disease: Three case reports

Bowen's disease (BD) is a relatively frequent non-melanoma skin cancer occurring mostly in elderly people. Until now, the usual way to establish the diagnosis is histopathological examination of a skin biopsy. Dermoscopy and reflectance confocal microscopy (RCM) are modern alternative methods that can be used as quick and non-invasive diagnostic techniques and as follow-up instruments in cases in which a conservative treatment is chosen for the management of BD. There are no very specific dermoscopic criteria for the diagnosis of this disease, but some dermoscopic features (scaly surface, vascular structures and pigmentation) can be found more frequent and can be helpful for the diagnosis. RCM of BD shows an acanthotic epidermis with two types of targetoid cells: the first, a large cell with bright center and dark peripheral halo, the second, a cell with dark center and a bright rim surrounded by a dark hallo, related with dyskeratotic cells on histological examination. BD management could be improved by using non-invasive, in vivo imaging techniques that allow a fast and easy diagnosis and can be used as follow-up tools. However, larger studies are necessary for the validation of our observations.

Vascular patterns in basal cell carcinoma: Dermoscopic, confocal and histopathological perspectives

Basal cell carcinoma (BCC) is the most prevalent skin cancer in the Caucasian population. A variety of different phenotypic presentations of BCC are possible. Although BCCs rarely metastasize, these tumors commonly destroy underlying tissues and should therefore be treated promptly. As vascular formation and angiogenesis are indicators of tumor development and progression, the presence of blood vessels, their morphology and architecture are important markers in skin lesions, providing critical information towards pathogenesis and diagnosis. BCC commonly lacks pigmentation, therefore it is important to emphasize the usefulness of vascular feature detection, recognition, quantification and interpretation. To answer the question of whether vascular patterns observed on dermoscopy, reflectance confocal microscopy (RCM) and histopathology might reflect the biologic behavior of BCCs, we undertook this review article. Several studies have sought, by various means, to identify vascular features associated with the more aggressive BCC phenotypes. Dermoscopic vascular pattern assessment can facilitate diagnostic discrimination between BCC subtypes, more aggressive BCCs displaying less or no pink coloration and a relative absence of central tumor vessels. RCM, a novel, non-invasive imaging technique, allows for the quantification of blood vessel size, density, and flow intensity in BCCs. BCCs are distinguished on RCM chiefly by vessels that branch and intertwine between neoplastic aggregates, a pattern strongly reflecting tumor neo-angiogenesis. The analysis of these vascular morphological and distribution patterns can provide further support in the diagnosis, assessment, or monitoring of BCCs. Histopathology shows significantly higher microvessel densities in the peritumoral stroma of BCCs, when compared to normal skin or benign tumors. This angiogenic response in the stroma is associated with local aggressiveness, therefore the quantification of peritumoralmicrovessels may further assist with tumor evaluation. How dermoscopy and RCM vascular patterns in BCC correlate with histopathological subtype and thus help in discriminating aggressive subtypes definitely deserves further investigation.

Reflectance confocal microscopy terminology glossary for nonmelanocytic skin lesions: A systematic review

BACKGROUND

There is lack of uniformity in reflectance confocal microscopy (RCM) terminology for nonmelanocytic lesions (NMLs).

OBJECTIVE

To review published RCM terms for NMLs and identify likely synonymous terms.

METHODS

We conducted a systematic review of original research articles published up to August 19, 2017, adhering to Preferred Reporting Items for Systemic Reviews and Meta-Analyses guidelines. Two investigators gathered all published RCM terms used to describe basal cell carcinoma (BCC), squamous cell carcinoma (SCC), and seborrheic keratosis/solar lentigo/lichen planus-like keratosis (SK/SL/LPLK). Synonymous terms were grouped on the basis of similarity in definition and histopathologic correlates.

RESULTS

The inclusion criteria was met by 31 studies. Average frequency of use per term was 1.6 (range 1-8). By grouping synonymous terms, the number of terms could be reduced from 58 to 18 for BCC, 58 to 36 for SCC, 23 to 12 for SK/SL/LPLK, and from 139 to 66 terms (52.5% reduction) in total. The frequency of term usage stratified by anatomic layer (suprabasal epidermis vs epidermal basal layer, dermoepidermal junction, and superficial dermis) was 27 (25.7%) versus 78 (74.2%) for BCC; 60 (64.5%) versus 33 (34.5%) for SCC, and 15 (45.4%) versus 18 (54.5%) for SK/SL/LPLK, respectively.

LIMITATIONS

Articles that were not peer reviewed were excluded.

CONCLUSION

Systematic review of published RCM terms provides the basis for future NMLs terminology consensus.

The challenge of diagnosing seborrheic keratosis by reflectance confocal microscopy

BACKGROUND

Seborrheic keratosis (SK) is one of the most common skin tumors seen by dermatologists. It should be differentiated with many diseases, especially skin tumors. Reflectance confocal microscopy (RCM) has been applied for evaluation of SK. There are a few studies that describe the RCM of SK. The aim of the study was to find the challenge of diagnosing seborrheic keratosis by reflectance confocal microscopy.

METHODS

A total of 390 patients with a clinical suspicious diagnosis of seborrheic keratosis were enrolled in this study, and lesions from each patient were imaged with RCM. Thirty-seven of these patients performed a biopsy in order to be given a histological diagnosis. We retrospectively analyzed the outcomes of RCM diagnosis and histological diagnosis, and then found the RCM characteristics of biopsy-proven lesions.

RESULTS

According to RCM images, 258 of 390 (66.2%) patients were diagnosed with SK, 97 of 390 (24.9%) patients could not be diagnosed by the dermatologist according to RCM. Of all 37 biopsied lesions, 23 were SK, 6 were actinic keratosis, 2 were basal cell carcinoma, and 2 were squamous cell carcinoma.

CONCLUSION

It is challenge to diagnose seborrheic keratosis by reflectance confocal microscopy. It may due to the variable clinical and RCM appearances of SK, and limited depth of RCM.

Using Reflectance Confocal Microscopy in Skin Cancer Diagnosis

Biopsy and histologic evaluation have been the gold standard to diagnose skin tumors. Reflectance confocal microcopy (RCM) is a noninvasive, innovative diagnostic technique that enables visualization of different skin layers at an almost histologic resolution. RCM has been proven beneficial in management of various cutaneous lesions. This article highlights the clinical significance and future of RCM to diagnose common skin cancers. However, RCM cannot replace currently standard histopathologic diagnosis. More studies are required to better compare the sensitivity and specificity of skin cancer diagnosis using RCM.

Dermoscopic and reflectance confocal microscopy features of cutaneous squamous cell carcinoma

BACKGROUND

Squamous cell carcinoma (SCC) of the skin is a highly prevalent neoplasm. The management and the prognosis of this tumour are dependent on its invasiveness and its grade of differentiation.

OBJECTIVES

To evaluate whether specific dermoscopic and reflectance confocal microscopy (RCM) criteria can predict the diagnosis of invasive SCC vs. in situ SCC and poorly differentiated compared with well- and moderately differentiated SCC.

METHODS

Dermoscopic and RCM images of SCC were retrospectively evaluated for the presence of predefined criteria.

RESULTS

Among 143 SCCs, 121 cases had a complete set of images and thus were included in the study set. The head and neck area was the most frequently involved body site (74/121; 61.1%) followed by extremities (36/121, 29.7%) and trunk (11/121, 9.1%). Seventy tumours were in situ (57.8%), while 51 were invasive (42.1%), of these 11 were poorly differentiated (21.5%), 16 were moderately differentiated (31.3%), and 24 were well differentiated (47.0%). Chi-squared analysis demonstrated that invasive SCCs were characterized by polymorphic vessels, erosion/ulceration, architectural disarrangement, speckled nucleated cells in the dermis, irregularly dilated vessels and absence of hyperkeratosis. Buttonhole vessels, white structureless areas and dotted or glomerular vessels were significantly associated with in situ lesions. Poorly differentiated SCCs were typified by red areas, erosion/ulceration and architectural disarrangement. Well- or moderately differentiated SCCs were associated with white areas and speckled nucleated cells in the epidermis.

CONCLUSION

Clinical, dermoscopic and RCM images provide useful information that should be integrated in order to achieve the optimal therapeutic management for the patient.

In vivo reflectance confocal microscopy features of a large cell acanthoma: report of a case

Reflectance confocal microscopy (RCM) is an FDA approved noninvasive optical imaging technique that acquires cellular level-resolution skin images in vivo. Herein, we report a case of histopathologically proven large cell acanthoma (LCA) whose RCM features simulate those of squamous cell carcinoma in situ.

Skin healing and collagen changes of rats after fractional erbium:yttrium aluminum garnet laser: observation by reflectance confocal microscopy with confirmed histological evidence

The fractional erbium:yttrium aluminum garnet (Er:YAG) laser is widely applied. Microstructural changes after laser treatment have been observed with histopathology. Epidermal and dermal microstructures have also been analyzed using reflectance confocal microscopy (RCM). However, no studies have compared these two types of microstructural changes in the same subject at multiple time points after irradiation, and it is unclear if these two types of changes are consistent. We use RCM to observe the effect of different laser energies on skin healing and collagen changes in the skin of Sprague-Dawley rats that had been irradiated by fractional Er:YAG lasering at different energies. RCM was used to observe skin healing and detect collagen changes at different time points. Collagen changes were observed using hematoxylin and eosin (H&E) staining and quantitatively analyzed by western blot. RCM showed that, irrespective of laser energy, microscopic treatment zones (MTZs) were larger at 1 day after irradiation. The MTZs then reduced in size from 3 to 7 days after irradiation. The higher the energy, the larger the MTZ area. The amount of collagen also increased with time from 1 day to 8 weeks. However, the increase in the collagen amount on both RCM and H&E staining was not influenced by the laser energy. Western blotting confirmed that the amount of type I and type III collagens increased over time, but there were no significant differences between the different energy groups (p > 0.05). In conclusion, RCM is a reliable technique for observing and evaluating skin healing and collagen expression after laser irradiation.

[Confocal laser scanning microscopy]

Reflectance confocal microscopy (RCM) allows the in vivo evaluation of melanocytic and nonmelanocytic skin tumours with high sensitivity and specificity. RCM represents an optical imaging technique, which enables us to examine the skin at high resolution. Today, RCM represents not only an interesting tool for dermatologic research but has also been introduced as a diagnostic tool in every day clinical practice. As such, RCM is applied for improvement of skin cancer diagnosis adjunct to clinical and dermatoscopic examination. In combination with dermatoscopy RCM has shown an increased specificity with similar sensitivity. In this regard RCM helps to decrease the rate of unnecessary biopsies of benign lesions. Despite its use in dermatooncology RCM may also be used for diagnosis and monitoring of inflammatory diseases. Future developments include technical improvements, teledermatology solutions and the application of ex vivo RCM in Moh's micrographic surgery.

Skin surgery, an evidence-based update: meeting report

The Evidence Based Update on Skin Surgery was held in Nottingham in May 2015. The meeting featured presentations on new diagnostic techniques, trials in development, discussions of recently published trials, and a question and answer session with an expert panel. This report aims to summarize the presentations and discussions from the day.

Non-invasive diagnostic techniques in the diagnosis of squamous cell carcinoma

Squamous cell carcinoma is the second most common cutaneous malignancy after basal cell carcinoma. Although the gold standard of diagnosis for squamous cell carcinoma is biopsy followed by histopathology evaluation, optical non-invasive diagnostic tools have obtained increased attention. Dermoscopy has become one of the basic diagnostic methods in clinical practice. The most common dermoscopic features of squamous cell carcinoma include clustered vascular pattern, glomerular vessels and hyperkeratosis. Under reflectance confocal microscopy, squamous cell carcinoma shows an atypical honeycomb or disarranged pattern of the spinous-granular layer of the epidermis, round nucleated bright cells in the epidermis and round vessels in the dermis. High frequency ultrasound and optical coherence tomography may be helpful in predominantly in pre-surgical evaluation of tumor size. Emerging non-invasive or minimal invasive techniques with possible application in the diagnosis of squamous cell carcinoma of the skin, lip, oral mucosa, vulva or other tissues include high-definition optical coherence tomography, in vivo multiphoton tomography, direct oral microscopy, electrical impedance spectroscopy, fluorescence spectroscopy, Raman spectroscopy, elastic scattering spectroscopy, differential path-length spectroscopy, nuclear magnetic resonance spectroscopy, and angle-resolved low coherence interferometry.

Grading keratinocyte atypia in actinic keratosis: a correlation of reflectance confocal microscopy and histopathology

BACKGROUND

Actinic Keratosis (AK) is the clinical manifestation of cutaneous dysplasia of epidermal keratinocytes, with progressive trend towards squamous cell carcinoma.

OBJECTIVE

To evaluate the strength of the correlation between keratinocyte atypia, as detected by Reflectance Confocal Microscopy (RCM) and histopathology, and to develop a more objective atypia grading scale for RCM quantification, through a discrete ranking.

METHODS

A total of 48 AKs and two control areas (photodamaged and non-photodamaged skin) were selected for this study. All these areas were documented by RCM and biopsied for histopathology. One representative image of the epidermis was selected for RCM and for histopathology and used for side-by-side comparison with purpose written software. The assessor chose which of two images displayed more keratinocyte atypia, and an ordered list from the image showing the least to the most keratinocyte atypia was generated. Three evaluations were obtained for RCM and two for histopathology.

RESULTS

Good interobserver correlation was obtained for RCM and histopathology grading, with high concordance between RCM and histopathology grading.

CONCLUSIONS

Expert rater scan consistently distinguish different grades of cytological atypia. Non-invasive RCM data from in vivo imaging can be graded for keratinocyte atypia, comparable to histopathological grading.

Reflectance confocal microscopy for monitoring the density of Demodex mites in patients with rosacea before and after treatment

BACKGROUND

Demodex mites seem to serve as a pathogenic trigger in many Demodex-associated diseases such as rosacea. In facial skin of patients with rosacea significantly higher numbers of Demodex mites have been shown compared with healthy controls. Reflectance confocal microscopy (RCM) allows the detection and quantification of Demodex mites in vivo noninvasively. It is hypothesized that a reduction of Demodex mites under rosacea therapy can be monitored by RCM.

OBJECTIVES

To use RCM to monitor the density of Demodex mites in patients with rosacea before and after treatment.

METHODS

In 25 patients with facial rosacea RCM was performed before and after therapy. Mosaics of 5 × 5 mm(2) and 8 × 8 mm(2) were scanned, and the total numbers of mites per follicle and per area were counted, along with the number of follicles per area.

RESULTS

In all patients Demodex folliculorum could be detected and quantified using RCM. RCM showed significant differences pre- and post-treatment (P = 0.0053 for 5 × 5 mm(2) and P < 0.001 for 8 × 8 mm(2)). The mean numbers of mites per follicle were 0.63 (range 0.16-2.28) per 8 × 8 mm(2) area and 0.70 (range 0.11-2.20) per 5 × 5 mm(2) area before treatment, and 0.41 (range 0.074-1.75) and 0.51 (range 0.094-1.70), respectively, after treatment. The corresponding mean numbers of mites were 155 (range 45-446) and 86.2 (range 12-286), respectively, before treatment and 96.2 (range 18-363) and 58.5 (range 12-230), respectively, after treatment.

CONCLUSIONS

By RCM, a reduction in the density of Demodex mites in facial skin of patients with rosacea under therapy, correlating to clinical improvement, can be quantified and monitored noninvasively. Possible reasons for this therapeutic effect are discussed.

Reflectance confocal microscopy: non-invasive distinction between actinic keratosis and squamous cell carcinoma

BACKGROUND

Early recognition of squamous cell carcinoma (SCC) is difficult. Non-invasive reflectance confocal microscopic (RCM) imaging of the skin is a promising diagnostic technique. Although several RCM features for SCC and AK have been described, it is not determined whether RCM has the ability to distinguish between SCC and actinic keratosis (AK).

OBJECTIVE

To determine in vivo reflectance confocal microscopic features that are specific for making a distinction between AK and SCC.

METHODS

In 24 patients, 30 lesions clinically suspicious for AK or SCC were selected for RCM imaging. Following the imaging procedure, a 3 mm skin biopsy was obtained for confirmation of the histopathological diagnosis. Two observers evaluated the RCM images according to a literature based list of RCM features. The obtained data were evaluated by an univariate and forward multivariate logistic regression analysis, kappa analysis and independent T-test.

RESULTS

The univariate logistic regression showed statistically significant odds ratios for several RCM features, including architectural disarray in the stratum granulosum, architectural disarray in the spinous layer and nest-like structures in the dermis. The forward multivariate logistic regression analysis showed that the combination of these features increased the ability to make the correct diagnosis AK and SCC non-invasively. The interobserver agreement between a starting and an experienced RCM observer ranged from poor to no agreement.

CONCLUSION

This study revealed specific RCM features that can distinguish between AK and SCC, stimulating further prospective, large cohort research in this field. This will result in correct, efficient and adequate diagnosis and treatment of clinically difficult to distinguish AK and SCC lesions.

Vascular patterns of nonpigmented tumoral skin lesions: confocal perspectives

BACKGROUND

The characteristic vascular patterns of nonpigmented skin tumors have been established by dermoscopy. Recently, in vivo reflectance confocal microscopy (RCM) has become an established method for the noninvasive examination of skin tumors.

OBJECTIVES

Determination of the value of RCM on the vascularity of nonpigmented skin tumors.

METHODS

One hundred and twenty two tumoral lesions have been evaluated by RCM in terms of their vascular structures. They were classified in five groups as basal cell carcinoma (BCC), seborrheic keratosis (SK), squamous cell carcinoma (SCC)/keratoacanthoma, actinic keratosis (AK)/Bowen disease and others. Vascular morphologies were investigated as curved linear, straight linear, branching, tubular/canalicular, round and polymorphic vessels in six types.

LIMITATIONS

Relatively, small number of patients with some tumor subgroups is limitation. Larger prospective studies are required before firm conclusions can be drawn.

RESULTS

Excellent compliance was obtained in interobserver analysis. Branching vessels had a high predictive value for basal cell carcinoma (BCC) with RCM (P < 0.001). Also vascular polymorphism was more frequently (69.4%) seen in malignant nonpigmented tumors (P < 0.05) than benign nonpigmented tumors (30.6%). Furthermore, vessels with opposite flows had high predictive value for malignant tumors (P < 0.05) compared with benign tumors.

CONCLUSION

Vascular properties can be evaluated in the diagnosis of nonpigmented tumoral skin lesions via RCM.

Confocal microscopy patterns in nonmelanoma skin cancer and clinical applications

Reflectance confocal microscopy is currently the most promising noninvasive diagnostic tool for studying cutaneous structures between the stratum corneum and the superficial reticular dermis. This tool gives real-time images parallel to the skin surface; the microscopic resolution is similar to that of conventional histology. Numerous studies have identified the main confocal features of various inflammatory skin diseases and tumors, demonstrating the good correlation of these features with certain dermatoscopic patterns and histologic findings. Confocal patterns and diagnostic algorithms have been shown to have high sensitivity and specificity in melanoma and nonmelanoma skin cancer. Possible present and future applications of this noninvasive technology are wide ranging and reach beyond its use in noninvasive diagnosis. This tool can also be used, for example, to evaluate dynamic skin processes that occur after UV exposure or to assess tumor response to noninvasive treatments such as photodynamic therapy. We explain the characteristic confocal features found in the main nonmelanoma skin tumors and discuss possible applications for this novel diagnostic technique in routine dermatology practice.

Noninvasive in vivo detection and quantification of Demodex mites by confocal laser scanning microscopy

BACKGROUND

In many Demodex-associated skin diseases Demodex mites are present in abundance and seem to be at least partially pathogenic. So far all diagnostic approaches such as scraping or standardized superficial skin biopsy are (semi-)invasive and may cause discomfort to the patient.

OBJECTIVES

To see whether confocal laser scanning microscopy (CLSM) - a noninvasive method for the visualization of superficial skin layers - is able to detect and quantify D. folliculorum in facial skin of patients with rosacea.

METHODS

Twenty-five patients (34-72 years of age) with facial rosacea and 25 age- and sex-matched normal controls were examined by CLSM. Mosaics of 8 × 8 mm and 5 × 5 mm were created by scanning horizontal layers of lesional skin and quantification of mites per follicle and per area as well as follicles per area was performed.

RESULTS

In all patients D. folliculorum could be detected by CLSM and presented as roundish or lengthy cone-shaped structures. CLSM allowed the quantification of Demodex mites and revealed significant differences (P < 0·0001): the mean number of mites was 165·4 per 8 × 8 mm area and 94·2 per 5 × 5 mm area in the patients compared with 34·7 and 22·4, respectively, in the controls. The corresponding mean number of mites per follicle was 0·7 and 0·8, respectively, in the patients and 0·1 and 0·2, respectively, in the controls.

CONCLUSIONS

With the help of CLSM it is possible to detect, image and quantify Demodex mites noninvasively in facial skin of patients with rosacea.

Fluorescence diagnosis and photodynamic therapy for Bowen's disease treatment

INTRODUCTION

It has already been demonstrated the high efficacy of photodynamic therapy (PDT) for Bowen's disease (BD) treatment. Fluorescence diagnosis consists on registration of the fluorescence emitted by tissue after application of a photosensitizer, indicating presence of tumoral cells. It has been described as a useful tool for actinic keratosis. Different results have been published about fluorescence diagnosis for basal cell carcinomas. Very few reports about the role of fluorescence diagnosis for this entity exist and this is the first one which correlates the fluorescence image after PDT with the histopathological response.

OBJECTIVES

To assess the role of fluorescence diagnosis during BD follow-up.

METHODS

We carried out an observational, retrospective and descriptive study. A total of 29 BD biopsy proven lesions were included. All the lesions had been treated with the standard protocol (Topical methyl- aminolaevulinic acid under occlusion for 3 hours and followed by illumination with red-light (630 nm, 38 J/cm(2), 7.5 minutes. Two sessions one week apart). Clinical and fluorescence photographs were taken before treatment and one month after the 2(nd) one. At that moment a post-treatment biopsy was performed. Clinical response was classified as partial, complete or no response. Fluorescence response was classified as negative, intermediate or intense. The follow-up period and the adverse events observed including pain were also collected.

RESULTS

We found statistical association between fluorescence and the clinical and histopathological evaluations performed after treatment. Fluorescence diagnosis obtained a 100% sensitivity (higher than clinical evaluation alone) and a specificity of 85.7% (CI: 70.8-100).

CONCLUSIONS

Fluorescence diagnosis seems a valid diagnostic tool, useful during the follow up of Bowen disease lesions with the advantage of avoiding unnecessary post-treatment biopsies.

Analysis of the efficiency of hair removal by different optical methods: comparison of Trichoscan, reflectance confocal microscopy, and optical coherence tomography

Noninvasive diagnostic tools, such as Trichoscan®, reflectance confocal microscopy (RCM), and optical coherence tomography (OCT), are efficient methods of hair shaft and growth evaluation. The aim of this study was to carry out a comparative assessment of these three medical procedures by measuring the hair shaft and hair growth after hair removal for a defined period of five days. The application of these techniques was demonstrated by measuring hair growth on the lower leg of six female volunteers. After removal of the hair shaft with a shaving system, the hair follicle infundibula and the length of the growing hairs were measured with the Trichoscan®, RCM, and OCT method. All three methods are reliable hair measuring tools after hair removal. Trichoscan® is best suited in the implementation of hair growth measurement and RCM in the analysis of hair follicles, whereas the OCT system can be consulted as an additional measurement for the evaluation of the hair follicle and length.