Dermoscopic and reflectance confocal microscopy features of cutaneous squamous cell carcinoma

An overview of cutaneous squamous cell carcinoma imaging diagnosis methods

Cutaneous squamous cell carcinoma, a type of non-melanoma skin cancer, is a form of keratinocyte carcinoma that stands as one of the most prevalent cancers, exhibiting a rising frequency. This review provides an overview of the latest literature on imaging methods for diagnosing squamous cell carcinoma (SCC) and actinic keratosis (AK). It discusses the diagnostic criteria, advantages, and disadvantages of various techniques such as dermatoscopy, skin ultrasound (US), in vivo and ex-vivo reflectance confocal microscopy (RCM), and line-field confocal optical coherence tomography (LC-OCT). These methods offer benefits including non-invasiveness, rapidity, comprehensive lesion imaging, and enhanced sensitivity, but face challenges like high costs and the need for specialized expertise. Despite obstacles, the use of these innovative techniques is expected to increase with ongoing technological advancements, improving diagnosis and treatment planning for keratinocyte carcinomas. Standardizing LC-OCT imaging algorithms for AK, Bowen's disease, and SCC remains an area for further research.

Diagnosis of invasive cutaneous squamous cell carcinoma, imaging and staging

The assessment of patients with a lesion raising the suspicion of an invasive cutaneous squamous cell carcinoma (cSCC) is a frequent clinical scenario. The management of patients with cSCC is a multistep approach, starting with the correct diagnosis. The two main diagnostic goals are to differentiate from other possible diagnoses and correctly recognize the lesion as cSCC, and then to determine the tumor spread (perform staging), that is if the patient has a common primary cSCC or a locally advanced cSCC, or a metastatic cSCC (with in-transit, regional lymph nodal, or rarely distant metastasis). The multistep diagnostic approach begins with the clinical characteristics of the primary cSCC, it is complemented with features with dermoscopy and, if available, reflectance confocal microscopy and is confirmed with histopathology. The tumor spread is assessed by physical examination and, in some cases, ultrasound and/or computed tomography or magnetic resonance imaging, mainly to investigate for regional lymph node metastasis or for local infiltration into deeper structures. In the last step, the clinical, histologic and radiologic findings are incorporated into staging systems.

[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.

International expert recommendations on image acquisition for in vivo reflectance confocal microscopy of cutaneous tumors

BACKGROUND

No international recommendations exist for a minimum imaging requirement per lesion using reflectance confocal microscopy (RCM). This may be beneficial given the increasing use of remote RCM interpretation internationally.

OBJECTIVE

To develop international expert recommendations for image acquisition using tissue-coupled RCM for diagnosis of cutaneous tumors.

METHODS

Using a modified Delphi approach, a core group developed the scope and drafted initial recommendations before circulation to a larger group, the Cutaneous Imaging Expert Resource Group of the American Academy of Dermatology. Each review round consisted of a period of open comment, followed by revisions.

RESULTS

The recommendations were developed after 5 alternating rounds of review among the core group and the Cutaneous Imaging Expert Resource Group. These were divided into subsections of imaging personnel, recommended lesion criteria, clinical and lesion information to be provided, lesion preparation, image acquisition, mosaic cube settings, and additional captures based on lesion characteristics and suspected diagnosis.

LIMITATIONS

The current recommendations are limited to tissue-coupled RCM for diagnosis of cutaneous tumors. It is one component of the larger picture of quality assurance and will require ongoing review.

CONCLUSIONS

These recommendations serve as a resource to facilitate quality assurance, economical use of time, accurate diagnosis, and international collaboration.

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.

European consensus-based interdisciplinary guideline for invasive cutaneous squamous cell carcinoma. Part 1: Diagnostics and prevention-Update 2023

Invasive cutaneous squamous cell carcinoma (cSCC) is one of the most common cancers in white populations, accounting for 20% of all cutaneous malignancies. Overall, cSCC mostly has very good prognosis after treatment, with 5-year cure rates greater than 90%. Despite the overall favourable prognosis and the proportionally rare deaths, cSCC is associated with a high total number of deaths due to its high incidence. A collaboration of multidisciplinary experts from the European Association of Dermato-Oncology (EADO), the European Dermatology Forum (EDF), the European Society for Radiotherapy and Oncology (ESTRO), the European Union of Medical Specialists (UEMS), the European Academy of Dermatology and Venereology (EADV) and the European Organization of Research and Treatment of Cancer (EORTC), was formed to update recommendations on cSCC, based on current literature and expert consensus. Part 1 of the guidelines addresses the updates on classification, epidemiology, diagnosis, risk stratification, staging and prevention in immunocompetent as well as immunosuppressed patients.

Reflectance confocal microscopy of facial neoplasms: Follicular involvement as a clue to diagnosis

BACKGROUND

Facial skin is characterized by high density of follicles. Facial neoplasms may present overlapping clinical and dermoscopic findings. Our goal was to evaluate and compare, via reflectance confocal microscopy (RCM), follicular involvement in facial neoplasms.

METHODS

We retrospectively searched our image database, between January 2008 and December 2020, for all facial lesions with (1) a standardized set of clinical, dermoscopic, and RCM images, and (2) a biopsy-proven diagnosis of lentigo maligna/lentigo maligna melanoma (LM/LMM, n = 39), basal cell carcinoma (BCC, n = 51), squamous cell carcinoma in situ (SCCIS, n = 5), actinic keratosis (AK, n = 11), and lichen-planus-like keratosis (LPLK, n = 18). Two readers jointly evaluated the RCM images for a set of predefined features of follicular involvement.

RESULTS

Diffuse obliteration of follicles was frequent in BCC (88%), while follicular infiltration by refractile dendritic cells and/or by bright round nucleated cells was common in melanoma (90% and 44%, respectively). Extension of atypical keratinocytes down follicles was more prominent among SCCIS than AK (80% vs. 45%, p = 0.01). In most LPLK (89%), there was follicular sparing.

CONCLUSIONS

Evaluation of RCM criteria centering on the follicles can be useful in the differential diagnosis between common facial neoplasms.

Comparison of reflectance confocal microscopy and line-field optical coherence tomography for the identification of keratinocyte skin tumours

BACKGROUND

Reflectance confocal microscopy (RCM) and line-field confocal optical coherence tomography (LC-OCT) are non-invasive imaging devices that can help in the clinical diagnosis of actinic keratosis (AK) and cutaneous squamous cell carcinoma (SCC). No studies are available on the comparison between these two technologies for the identification of the different features of keratinocyte skin tumours.

OBJECTIVES

To compare RCM and LC-OCT findings in AK and SCC.

METHODS

A retrospective multicenter study was conducted. Tumours were imaged with RCM and LC-OCT devices before surgery, and the diagnosis was confirmed by histological examinations. LC-OCT and RCM criteria for AK/SCC were identified, and their presence/absence was evaluated in all study lesions. Gwet AC1 concordance index was calculated to compare RCM and LC-OCT.

RESULTS

We included 52 patients with 33 AKs and 19 SCCs. Irregular epidermis was visible in most tumours and with a good degree of agreement between RCM and LC-OCT (Gwet's AC1 0.74). Parakeratosis, dyskeratotic keratinocytes and both linear dilated and glomerular vessels were better visible at LC-OCT than RCM (p < 0.001). Erosion/ulceration was identified with both methods in more than half of the cases with a good degree of agreement (Gwet AC1 0.62).

CONCLUSIONS

Our results suggest that both LC-OCT and hand-held RCM can help clinicians in the identification of AK and SCC, providing an in vivo and non-invasive identification of an irregular epidermis. LC-OCT proved to be more effective in identifying parakeratosis, dyskeratotic keratinocytes and vessels in this series.

Characteristics and management of skin cancers in very elderly patients: A real-world challenge for clinicians

The increase life expectancy led to an expected increase in skin cancer incidence in older patients. Their treatment can require a complex decision-making process. Limited data are available on characteristics, management and outcome of skin tumours in nonagenarian and centenarian patients. The aim of our study was to describe epidemiology, clinical-pathological features and treatment strategies of skin cancers in a cohort of patients aged ≧95 years. A total of 116 patients ≧95 years of age presented for the evaluation of 225 skin lesions (mean of 1.94 lesions per patient). The mean age was 97.4 years, 57.8% were women. Most patients had an ECOG score of 3 (49.3%) or 4 (32%). Lesions were mainly located on the head and neck area (74.2%), upper (7.1%) and lower (6,2%) limbs. The majority of patients presented with non-melanoma skin cancers (183/225; 81.3%), 25/225 (11.1%) had actinic keratosis, 5 (2.2%) melanoma and 2 (0.9%) atypical fibroxanthoma. Forty-eight lesions (21.3%) were treated with surgery, 58 (25.8%) with radiotherapy. The management of 73 lesion (32.4%) was discussed at the multidisciplinary tumour board meeting. One patient died for the progression of a squamous cell carcinoma; 74 patients died for causes unrelated to skin tumours, 36 are still alive after a mean follow-up of 27.27 months. This cohort study confirms that age is not per se a contraindication for treatment of skin cancers in elderly patients. Our results support the importance of a patient-centred care approach that should take into consideration patient's preferences, comorbidities, compliance and possible adverse events.

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.

Cryotherapy for Actinic Keratosis: Basic Principles and Literature Review

Actinic keratoses (AKs) are pre-malignant epithelial lesions induced by chronic cumulative UV exposure. Several guidelines concerning AKs treatment have been published in the past years. Among destructive procedures, cryotherapy is today considered a standard first-line approach in case of single lesions. The aim of the present review article is to analyse the treatment technique, its efficacy and safety.

In vivo optical imaging-guided targeted sampling for precise diagnosis and molecular pathology

Conventional tissue sampling can lead to misdiagnoses and repeated biopsies. Additionally, tissue processed for histopathology suffers from poor nucleic acid quality and/or quantity for downstream molecular profiling. Targeted micro-sampling of tissue can ensure accurate diagnosis and molecular profiling in the presence of spatial heterogeneity, especially in tumors, and facilitate acquisition of fresh tissue for molecular analysis. In this study, we explored the feasibility of performing 1–2 mm precision biopsies guided by high-resolution reflectance confocal microscopy (RCM) and optical coherence tomography (OCT), and reflective metallic grids for accurate spatial targeting. Accurate sampling was confirmed with either histopathology or molecular profiling through next generation sequencing (NGS) in 9 skin cancers in 7 patients. Imaging-guided 1–2 mm biopsies enabled spatial targeting for in vivo diagnosis, feature correlation and depth assessment, which were confirmed with histopathology. In vivo 1-mm targeted biopsies achieved adequate quantity and high quality of DNA for next-generation sequencing. Subsequent mutational profiling was confirmed on 1 melanoma in situ and 2 invasive melanomas, using a 505-gene mutational panel called Memorial Sloan Kettering-Integrated mutational profiling of actionable cancer targets (MSK-IMPACT). Differential mutational landscapes, in terms of number and types of mutations, were found between invasive and in situ melanomas in a single patient. Our findings demonstrate feasibility of accurate sampling of regions of interest for downstream histopathological diagnoses and molecular pathology in both in vivo and ex vivo settings with broad diagnostic, therapeutic and research potential in cutaneous diseases accessible by RCM-OCT imaging.

Line-field confocal optical coherence tomography for the in vivo real-time diagnosis of different stages of keratinocyte skin cancer: a preliminary study

BACKGROUND

The treatment of keratinocyte cancers (KC) strictly depends on their differentiation and invasiveness. Non-invasive diagnostic techniques can support the diagnosis in real time, avoiding unnecessary biopsies. This study aimed to preliminarily define main imaging criteria and histological correlations of actinic keratosis (AK), Bowen's disease (BD) and squamous cell carcinoma (SCC) using the novel device line-field confocal optical coherence tomography (LC-OCT).

METHODS

Dermoscopy and LC-OCT images of 73 histopathologically confirmed lesions (46 AKs, 11 BD and 16 SCCs) were included in the study. Exemplary lesions (10 AKs, 5 BD and 5 SCCs) were additionally investigated with optical coherence tomography and reflectance confocal microscopy.

RESULTS

Most common LC-OCT findings of KC in the descriptive statistics were hyperkeratosis/parakeratosis, disruption of stratum corneum, broadened epidermis, basal and suprabasal keratinocyte atypia, dilated vessels/neoangiogenesis and elastosis/collagen alterations. In the univariate multinomial logistic regression, a preserved DEJ was less common in SCC compared with AK and BD, BD displayed marked keratinocyte atypia involving all epidermal layers (bowenoid pattern), while SCC showed ulceration, increased epidermal thickness, keratin plugs, acantholysis, not visible/interrupted DEJ and epidermal bright particles. LC-OCT increased the diagnostic confidence by 24.7% compared with dermoscopy alone.

CONCLUSIONS

Our study describes for the first time specific LC-OCT features of different stages of KC and their histopathological correlates, focusing on keratinocyte morphology and architecture of the epidermis and DEJ. LC-OCT may open new scenarios in the bedside diagnosis, treatment planning and follow-up of KC.

Usefulness of Dermoscopy to Provide Accurate Assessment of Skin Cancers

Seborrheic keratosis (SK) is the most common benign tumour of epidermal origin. In most cases, it is simple to recognize in the clinical examination. However, sometimes SK can be a problematic lesion. We present the cases of two patients with seborrheic keratosis in whom we diagnosed the skin cancer through dermoscopic and histopathological examinations. The article aims to draw attention to the need for dermoscopic examinations to be included for an accurate assessment of the nevi not only by dermatologists but also not-specialized doctors. We would like to underline that many skin cancers share the similar features of malignancy, and competence and capability to interpret the dermoscopic pictures correctly are important for early recognition of malignant lesion. Very often malignant skin cancers can be hidden among benign lesions like seborrheic keratosis or they can be imitators of benign lesions. Amongst all cases of imposing SK, basal cell carcinoma, squamous cell carcinoma, melanoma is the most important differential diagnosis, of which their dermoscopic features will be discussed in this article.

Reflectance Confocal Microscopy of Aging Skin and Skin Cancer

Skin aging is a complex process that causes morphologic variations. Some of these variations have been hypothesized to be involved in skin cancer development. This paper reviews current knowledge of the features of aged skin as seen with reflectance confocal microscopy (RCM). Basic principles of the technique are described, and the RCM features of healthy skin and skin cancer are briefly discussed. Moreover, the RCM features at different layers of young and elderly skin are described, as are the variations that occur with passing years and in relation to sun exposure that contribute to photoaging and the development of skin cancer. RCM enables the noninvasive evaluation, at quasi-histologic resolution, of aging-related skin changes, some of which are shared with skin cancer; this ability helps avoid skin biopsy. Further research is needed to understand the relation between skin aging and skin cancer development.

Acquired White Oral Lesions with Specific Patterns: Oral Lichen Planus and Lupus Erythematosus

Background

Diagnosis of oral white lesions might be challenging. These lesions represent a wide spectrum of diseases with different etiology and prognosis. Oral white lesions can be categorized into two major groups, congenital and acquired, according to their development, and in four subgroups: lesions which can be scraped off or not and lesions with special pattern or not.

Objectives

The aim of this manuscript is to review, from diagnosis to treatment, the current knowledge on oral white lesions with specific pattern.

Methods

A review on oral white lesions with specific pattern was conducted on PubMed and Scopus from inception to January 2021.

Results

Among acquired lesions with specific pattern two clinical entities are mostly represented: Oral lichenoid reactions and Lupus erythematosus. The etiology of both diseases is still not known but their pathogenesis is mainly immunological. At present the mucoscopic features of those disease have been described only in few case reports or case series. Immunomodulatory therapies are often the agents of choice for their treatment.

Conclusions

The collaboration of dermatologists and dentists as a team is important for early diagnoses and effective treatments. Mucoscopy is a promising technique which may reveal important features for the differentiation of OLP and LE oral white lesions.

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.

Cutaneous Squamous Cell Carcinoma: From Pathophysiology to Novel Therapeutic Approaches

Cutaneous squamous cell carcinoma (cSCC), a non-melanoma skin cancer, is a keratinocyte carcinoma representing one of the most common cancers with an increasing incidence. cSCC could be in situ (e.g., Bowen’s disease) or an invasive form. A significant cSCC risk factor is advanced age, together with cumulative sun exposure, fair skin, prolonged immunosuppression, and previous skin cancer diagnoses. Although most cSCCs can be treated by surgery, a fraction of them recur and metastasize, leading to death. cSCC could arise de novo or be the result of a progression of the actinic keratosis, an in situ carcinoma. The multistage process of cSCC development and progression is characterized by mutations in the genes involved in epidermal homeostasis and by several alterations, such as epigenetic modifications, viral infections, or microenvironmental changes. Thus, cSCC development is a gradual process with several histological- and pathological-defined stages. Dermoscopy and reflectance confocal microscopy enhanced the diagnostic accuracy of cSCC. Surgical excision is the first-line treatment for invasive cSCC. Moreover, radiotherapy may be considered as a primary treatment in patients not candidates for surgery. Extensive studies of cSCC pathogenic mechanisms identified several pharmaceutical targets and allowed the development of new systemic therapies, including immunotherapy with immune checkpoint inhibitors, such as Cemiplimab, and epidermal growth factor receptor inhibitors for metastatic and locally advanced cSCC. Furthermore, the implementation of prevention measures has been useful in patient management.

The first report of diagnosing of keratoacanthoma in Chinese Han patients using dermoscopy and reflectance confocal microscopy

BACKGROUND

Keratoacanthoma (KA) is a special kind of tumor, which is regarded as a variant of squamous cell carcinoma (SCC) in some academic disciplines. But differentiating KA from SCC remains a diagnostic challenge. The noninvasive techniques dermoscopy and reflectance confocal microscopy (RCM) can provide new insights for diagnosis.

OBJECTIVE

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

METHODS

We collected two cases of KA, which were confirmed by clinical and histopathological examination. The two cases were examined by dermoscopy and RCM, respectively. Then, we collected the microscopic characteristics of KA lesions.

RESULTS

The dermoscopy features of KA are concentric circles of central crater, keratin mass, keratin scale, and polymorphic vascular pattern. The RCM features are described as refractile crust, atypical honeycomb pattern, dark center cells, large round nucleated cells, dendritic cells, and linear or round vessels traversing dermal papillae in the dermis.

CONCLUSION

KA has some specific dermoscopy and RCM features, which can provide a basis for doctors to diagnose and intervene earlier.

Cauliflower-like exophytic mass on the skin: polypoid melanoma. Clinical, dermoscopic, and histologic features

Polypoid melanoma is a variant of nodular melanoma, whose poor prognosis depends on its thickness and the presence of ulceration at the time of diagnosis. The authors report two cases of polypoid melanoma, presenting as broad, cauliflower-like, polypoid masses. Dermoscopy was characterized by a multicolored pattern, atypical polymorphic vessels, and the fiber sign. Clinical and dermoscopic features can help to diagnose polypoid melanoma and exclude other possible differential diagnoses. However, histology remains mandatory to confirm the diagnostic suspicion.

Dermoscopy and Reflectance Confocal Microscopy in the Diagnosis and Management of Nail Fold Squamous Cell Carcinoma

The management and prognosis of squamous cell carcinoma largely depend on its invasiveness and grade of differentiation. Pigmented nail fold squamous cell carcinoma represents a therapeutic challenge, needing careful treatment to preserve nail function. Here, we report the use of dermoscopy and Reflectance Confocal Microscopy to monitor nail fold squamous cell carcinoma in situ and its response to treatment with topical imiquimod.

Reflectance confocal microscopy: Diagnostic criteria of common benign and malignant neoplasms, dermoscopic and histopathologic correlates of key confocal criteria, and diagnostic algorithms

Reflectance confocal microscopy (RCM) is a high-resolution, noninvasive tool that is currently approved by the US Food and Drug Administration for obtaining and interpreting images of the skin and cutaneous neoplasms with the goal of decreasing unnecessary biopsy procedures in patients with benign lesions. The second article in this continuing medical education series focuses on identifying key criteria for the diagnosis of common skin cancers-melanoma, basal cell carcinoma, and squamous cell carcinoma. We contrast these findings with RCM features of common benign lesions-melanocytic nevi, solar lentigo, seborrheic keratosis, lichen planus-like keratosis, and sebaceous hyperplasia. We also correlate the dermoscopic and histopathologic findings with the RCM features.

European interdisciplinary guideline on invasive squamous cell carcinoma of the skin: Part 1. epidemiology, diagnostics and prevention

Invasive cutaneous squamous cell carcinoma (cSCC) is one of the most common cancers in the white populations, accounting for 20% of all cutaneous malignancies. Factors implicated in cSCC etiopathogenesis include ultraviolet radiation exposure and chronic photoaging, age, male sex, immunosuppression, smoking and genetic factors. A collaboration of multidisciplinary experts from the European Dermatology Forum (EDF), the European Association of Dermato-Oncology (EADO) and the European Organisation of Research and Treatment of Cancer (EORTC) was formed to update recommendations on cSCC classification, diagnosis, risk stratification, staging and prevention, based on current literature, staging systems and expert consensus. Common cSCCs are typically indolent tumors, and most have a good prognosis with 5-year cure rates of greater than 90%, and a low rate of metastases (<4%). Further risk stratification into low-risk or high-risk common primary cSCC is recommended based on proposed high-risk factors. Advanced cSCC is classified as locally advanced (lacSCC), and metastatic (mcSCC) including locoregional metastatic or distant metastatic cSCC. Current systems used for staging include the American Joint Committee on Cancer (AJCC) 8th edition, the Union for International Cancer Control (UICC) 8th edition, and Brigham and Women's Hospital (BWH) system. Physical examination for all cSCCs should include total body skin examination and clinical palpation of lymph nodes, especially of the draining basins. Radiologic imaging such as ultrasound of the regional lymph nodes, magnetic resonance imaging (MRI), computed tomography (CT), positron emission tomography-computed tomography (PET-CT) scans are recommended for staging of high-risk cSCC. Sentinel lymph node biopsy is currently not recommended. Nicotinamide, oral retinoids, and topical 5-FU have been used for the chemoprevention of subsequent cSCCs in high-risk patients but are not routinely recommended. Education about sun protection measures including reducing sun exposure, use of protective clothing, regular use of sunscreens and avoidance of artificial tanning, is recommended.

In vivo confocal microscopy of dermoscopic suspicious lesions in patients with xeroderma pigmentosum: A cross-sectional study

BACKGROUND

Xeroderma pigmentosum (XP) is a rare genetic disease characterized by extreme photosensitivity, resulting in a higher incidence of cutaneous tumors. Reflectance confocal microscopy (RCM) is a noninvasive imaging method for diagnosing cutaneous lesions.

OBJECTIVE

To explore the application of RCM in the follow-up of patients with XP.

METHODS

Patients with XP underwent RCM for suspicious lesions from January 2010 through April 2019. Lesions with malignant RCM features were excised, and the results were compared with their histopathologic features. Benign lesions on RCM were monitored every 3 months. We recorded the confocal features that were related to malignancy and specifically to melanoma.

RESULTS

A total of 61 suspicious lesions from 13 patients with XP were included. Thirty-three lesions (54%) were malignant (14 melanomas, 15 basal cell carcinomas, and 4 squamous cell carcinomas). Nonvisible papillae (OR, 11.8; 95% CI, 2.6-53.1; P = .001) and atypical cells at the dermoepidermal junction (OR, 11.7; 95% CI, 2.7-50.3; P = .001) were independent predictors of malignancy.

LIMITATIONS

There were limited numbers of patients and lesions. Most cases were retrospectively included, and some did not have a histologic analysis.

CONCLUSIONS

RCM is a valuable tool in the follow-up of patients with XP, reducing the need for excisions by 35%.

Cutaneous keratinocyte cancers of the head and neck: Epidemiology, risk factors and clinical, dermoscopic and reflectance confocal microscopic features

Keratinocyte cancers are the most common malignancy among people with European ancestry, and are very common on sun-exposed areas of the head and neck. Incidence is directly correlated with latitude and annual ultraviolet radiation incidence, although there are a number of other environmental, occupational and genetic risk factors, and keratinocyte cancers become more common at middle age. Basal cell carcinomas (BCC) are the most common, comprising 80% of keratinocyte cancers, but have a very low rate of metastases and low mortality. Squamous cell carcinomas (SCC) make up 20% of keratinocyte cancers, and have relatively infrequent metastases, at 5-16%. While there are no precursor lesions for BCC, SCC represents the final stage in a spectrum of cellular atypia and dysplasia, from actinic keratoses to in situ SCC to invasive SCC. Dermoscopy is a well-established diagnostic tool for keratinocyte cancers, and reflectance confocal microscopy is emerging as another useful diagnostic tool, particularly on functionally and cosmetically sensitive sites like the face.

Dermoscopy of Melanoma and Non-melanoma Skin Cancers

Dermoscopy is a widely used non-invasive technique for diagnosing skin tumors. In melanocytic tumors, e.g., melanoma and basal cell carcinoma (BCC), the effectiveness of dermoscopic examination has been fully established over the past two decades. Moreover, dermoscopy has been used to diagnose non-melanocytic tumors. Here, we review novel findings from recent reports concerning dermoscopy of melanoma and non-melanoma skin cancers including BCC, sebaceous carcinoma, actinic keratosis, Bowen's disease, squamous cell carcinoma (SCC), Merkel cell carcinoma (MCC), extramammary Paget's disease (EMPD), and angiosarcoma.

Non-invasive monitoring of subclinical and clinical actinic keratosis of face and scalp under topical treatment with ingenol mebutate gel 150 mcg/g by means of reflectance confocal microscopy and optical coherence tomography: New perspectives and comparison of diagnostic techniques

Actinic keratosis (AK) corresponds to the earliest stage of in situ squamous cell carcinoma and arises on chronically sun-exposed skin. Around the clinically evident AKs, the apparently healthy epidermis may contain different grades of atypia that can be detected by noninvasive imaging techniques such as reflectance confocal microscopy (RCM) and optical coherence tomography (OCT). Subclinical actinic keratosis (sAK) has captured increasing interest as a potential target of field therapies. The aim of this study was to evaluate in vivo the changes in the field cancerization undergoing treatment with topical ingenol mebutate by combining RCM and OCT. Twenty patients with field cancerization of the face and scalp were treated with ingenol mebutate gel (150 mcg/g) for three consecutive days on an area of 25 cm² containing at least two AKs, two sAKs and two apparently healthy sites. About 120 lesions were evaluated through clinical investigation and clinical, dermoscopical, RCM and OCT images at day 0, 4, 14 and 56 based on the diagnostic criteria for AKs. Main pathological features improved in both AKs and sAKs, in particular the epidermal thickness measured by OCT and the epidermal atypia graded by RCM. Local skin reactions (LSR) arose predominantly in the lesional area compared with healthy skin. A complete clearance was detected in 58% for AKs, and in 55% and 72% for sAKs measured by RCM and OCT, respectively. Both OCT and RCM allow the morphological representation of field cancerization including subclinical lesions and provide complementary information. Ingenol mebutate is effective not only in clinically evident but also in sAKs. The differences in LSR highlight the potential selectivity of the treatment.

Reflectance Confocal Microscopy Can Help the Dermatopathologist in the Diagnosis of Challenging Skin Lesions

Despite the successful assignment of Current Procedural Terminology codes, there are barriers to incorporating in vivo reflectance confocal microscopy (RCM) into daily practice. Importantly, the dermatopathologist can play a key role in interpreting RCM images and can use these images to correlate with histopathology. Herein, we describe, using a case series, how RCM can be incorporated into the dermatopothalogist's practice. We also summarize the criteria for RCM diagnosis of common neoplasms.

Ex vivo fluorescence confocal microscopy: the first application for real-time pathological examination of prostatic tissue

OBJECTIVE

To report the first application of ex vivo fluorescence confocal microscopy (FCM) - a novel optical technology that is capable of providing fast microscopic imaging of unfixed tissue specimens- in the urological field assessing its diagnostic accuracy for non neoplastic and cancerous prostate tissue (prostatic adenocarcinoma) compared to the 'gold standard' histopathological diagnoses.

PATIENTS AND METHODS

In all, 89 specimens from 13 patients with clinically localised prostate cancer were enrolled into the study. All patients underwent robot-assisted laparoscopic radical prostatectomy with fresh prostatic tissue biopsies taken at the end of each intervention using an 18-G biopsy punch. Specimens were randomly assigned to the three collaborating pathologists for evaluation. Intra- and inter-observer agreement was tested by the means of Cohen's κ. The diagnostic performance was evaluated on receiver operating characteristic curve analysis.

RESULTS

The overall diagnostic agreement between FCM and histopathological diagnoses was substantial with a 91% correct diagnosis (κ = 0.75) and an area under the curve of 0.884 (95% confidence interval 0.840-0.920), 83.33% sensitivity, and 93.53% specificity.

CONCLUSION

FCM seems to be a promising tool for enhanced specimens' reporting performance, given its simple application and very rapid microscopic image generation (<5 min/specimen). This technique may potentially be used for intraoperative pathological specimens' analysis.

Squamous Cell Carcinoma In Situ With Occult Invasion: A Tertiary Care Institutional Experience

BACKGROUND

The rate of occult invasive disease within biopsy-proven squamous cell carcinoma in situ (SCCIS) is not well defined.

OBJECTIVE

To examine the rate of occult invasion in SCCIS.

METHODS

An institutional-wide pathology database was retrospectively searched for "squamous cell carcinoma in situ" over a 6-year period, and the treatment modality and final pathology results were analyzed for evidence of invasion. In addition, consecutive tumor blocks from Mohs micrographic surgery (MMS) cases of SCCIS were prospectively analyzed for invasion.

RESULTS

The rate of occult invasion for biopsy-proven SCCIS treated with excision was 4.0% (N = 49) and for the MMS margins was 3.5% (N = 310). For the prospective MMS tumor block analysis, the rate of occult invasion was 10.1% (N = 69). No clinical factors (age, sex, location, or size) correlated with increased risk of invasion. All invasive SCCs detected were superficial and well differentiated.

CONCLUSION

The rate of occult invasion for biopsy-proven SCCIS ranged from 3.5% to 10.1%. The detected rate of invasion varies based on the method of excision and pathology processing of specimens. The rate of invasion should be considered when managing SSCIS.

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.

Diagnostic Accuracy of Reflectance Confocal Microscopy for Diagnosis of Skin Lesions: An Update

Context.—

Histopathology is the current standard to diagnose skin disease. However, biopsy may not always be feasible, such as in patients with multiple nevi, a patient with a lesion on an aesthetically significant site, or in children. Recently, noninvasive techniques, including reflectance confocal microscopy (RCM), optical coherence tomography, and Raman spectroscopy, have enabled dermatologists to manage skin lesions in real time without the need for biopsy.

Objective.—

To report the updated diagnostic accuracy of RCM for equivocal skin lesions.

Design.—

In this study, we retrospectively reviewed our data of clinically suspicious lesions from 2010 to 2017 that were evaluated by RCM.

Results.—

Our results showed an overall sensitivity of 98.2% and specificity of 99.8%.

Conclusions.—

In conclusion, RCM is a noninvasive real-time tool with the potential to diagnose skin lesions with high accuracy and without biopsy.

Ex vivo confocal microscopy features of cutaneous squamous cell carcinoma

BACKGROUND

Rapid microscopic evaluation of cutaneous squamous cell carcinoma (SCC), its grade of differentiation and level of invasiveness would enable better management of patients' therapy.

OBJECTIVES

Analyzing specific ex vivo confocal microscopy criteria whether they can predict diagnosis of invasive SCC vs carcinoma in situ and poorly differentiated or undifferentiated vs well and moderately differentiated SCC.

METHODS

Ex vivo confocal images of 102 SCCs in 57 patients were evaluated immediately after excision for the presence of predefined criteria based on confocal and histological knowledge.

RESULTS

In histopathological examination, 30 SCCs were in situ and 72 invasive. Of these, 29 invasive SCC tumors were well, 19 moderately, 15 poorly differentiated and 9 undifferentiated. χ² analysis demonstrated that presence of erosion/ulceration, plump bright or speckled cells in dermis, keratin pearls and peritumoral inflammatory infiltrate correlated with diagnosis of invasive SCC. Erosion/ulceration and peritumoral inflammatory infiltrate were observed more frequently in poorly differentiated or undifferentiated tumors. Plump bright or speckled cells in the dermis were observed less often in well-differentiated tumors. The presence of keratin pearls was associated with well or moderately differentiated tumors.

CONCLUSION

Ex vivo CLSM allowed rapid examination of SCC and provided useful information on invasiveness and grading of the tumor.