Dermatoscopic Patterns of Nonfacial Actinic Keratosis: Characterization of Pigmented and Nonpigmented Lesions

[Translated article] Dermoscopy of Squamous Cell Carcinoma: From Actinic Keratosis to Invasive Forms

When the dermoscopy of squamous cell carcinoma and its precursors we differentiate among keratin-related, vascular, and pigment-related criteria. Non-pigmented actinic keratoses are characterized by the "strawberry pattern". Pigmented actinic keratosis shows a significant dermatoscopic overlap with lentigo maligna, but the presence of pigmented scales, erythema, and prominent follicles favors its diagnosis. Bowen's disease is characterized by clustered glomerular vessels, white-yellowish scales, and brown or grey dots arranged in lines in its pigmented variant. Finally, dermoscopy allows us to detect invasive squamous cell carcinoma in its early stages and differentiate it from its precursors. Furthermore, its presentation may vary depending on the degree of differentiation, with keratin-associated criteria predominating in well-differentiated tumors, while an atypical vascular pattern will predominate in poorly differentiated tumors.

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.

Evaluation of dermatoscopic criteria for early detection of squamous cell carcinoma arising on an actinic keratosis

BACKGROUND

Advanced squamous cell carcinoma (SCC) can be discriminated easily from actinic keratosis (AK) based on clinical and dermatoscopic features. However, at the initial stage of dermal invasion, SCC might still be clinically flat and discrimination from AK remains challenging, even with the addition of dermatoscopy.

OBJECTIVE

The aim of this study was to investigate the clinical and dermatoscopic criteria that could suggest early invasion and serve as potent predictors to discriminate early SCC from AK.

METHODS

Clinical and dermatoscopic images of histopathologically diagnosed AKs and early SCCs were evaluated for the presence of predefined criteria by 3 independent investigators.

RESULTS

A total of 50 early SCCs and 45 AKs were included. The main positive dermatoscopic predictors of early SCC were dotted/glomerular vessels (odds ratio [OR] 3.83), hairpin vessels (OR 12.12), and white structureless areas (OR 3.58), whereas background erythema represented a negative SCC predictor (OR 0.22).

LIMITATIONS

The retrospective evaluation of images. Moreover, the differential diagnosis included in the study is restricted between AK and early SCC.

CONCLUSIONS

We identified potent predictors for the discrimination of AK and early SCC that may better guide management decisions in everyday clinical practice.

Diagnostic Accuracy of Dermoscopy of Actinic Keratosis: A Systematic Review

INTRODUCTION

Dermoscopy is a tool that aids clinicians in the diagnosis of actinic keratosis; however, few diagnostic accuracy studies have determined its sensitivity and specificity for this diagnosis.

OBJECTIVE

Determine the diagnostic accuracy of dermoscopy on actinic keratosis.

METHODS

A systematic review was conducted on EMBASE, PubMed, Scopus and the Cochrane Central Registry of Controlled Trials from inception to August 2019.

RESULTS

We screened 485 titles and abstracts. Two studies comprising 219 actinic keratoses were eligible for qualitative analysis. The number and heterogeneity of included studies limited a quantitative analysis.

CONCLUSIONS

Studies that focus specifically on the diagnostic accuracy of dermoscopy for actinic keratosis are lacking.

Actinic keratoses: review of clinical, dermoscopic, and therapeutic aspects

Actinic keratoses are dysplastic proliferations of keratinocytes with potential for malignant transformation. Clinically, actinic keratoses present as macules, papules, or hyperkeratotic plaques with an erythematous background that occur on photoexposed areas. At initial stages, they may be better identified by palpation rather than by visual inspection. They may also be pigmented and show variable degrees of infiltration; when multiple they then constitute the so-called field cancerization. Their prevalence ranges from 11% to 60% in Caucasian individuals above 40 years. Ultraviolet radiation is the main factor involved in pathogenesis, but individual factors also play a role in the predisposing to lesions appearance. Diagnosis of lesions is based on clinical and dermoscopic examination, but in some situations histopathological analysis may be necessary. The risk of transformation into squamous cell carcinoma is the major concern regarding actinic keratoses. Therapeutic modalities for actinic keratoses include topical medications, and ablative and surgical methods; the best treatment option should always be individualized according to the patient.

Noninvasive Imaging Tools in the Diagnosis and Treatment of Skin Cancers

In the 1980s, the increasing incidence of skin cancers prompted the development of noninvasive medical devices to improve skin cancer diagnosis in daily dermatology practice. As a result of the development of these noninvasive techniques, diagnosis is now established earlier and with better accuracy. These advances are of great benefit to high-risk patients, who previously would have had to undergo several excisions. In this review, we focus on the classic technique of dermoscopy and the more recent digital version, as well as on advanced noninvasive imaging techniques, such as reflectance confocal microscopy and optical coherence tomography. On the basis of their specific features, these noninvasive medical devices can be used not only to diagnose and monitor melanoma and nonmelanoma skin cancers but also to choose the best therapy and follow the patient's response to treatment in vivo.