Rosettes in actinic keratosis and squamous cell carcinoma: distribution, association to other dermoscopic signs and description of the rosette pattern

Dermoscopy of Squamous Cell Carcinoma: From Actinic Keratosis to Invasive Forms

When performing 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 the atypical vascular pattern will predominate in poorly differentiated tumors.

[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.

A Systematic Review of Diagnoses with Rosettes Under Dermoscopy

INTRODUCTION

Rosettes are a cluster of shiny white dots in the shape of a four-leaf clover seen under polarized dermoscopic light. Historically, rosettes were primarily reported in actinic keratoses and squamous cell carcinoma. However, rosettes have also been reported in other conditions.

OBJECTIVES

The objective of this systematic review to elucidate the breadth of diagnoses exhibiting this unique dermoscopic phenomenon.

METHODS

A review was conducted following Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. Literature searches were performed in MEDLINE, EMBASE, Cochrane Central Register of Controlled Trials and Web of Science, as well as a manual search of the reference lists of screened articles.

RESULTS

A total of 73 articles met the inclusion criteria. Out of these, 47 distinct diagnoses with rosette were identified. Among neoplastic conditions, keratinizing neoplasms had the highest number of articles reported (N = 19). Discoid lupus was the most commonly reported diagnosis within the inflammatory category (N = 6). Molluscum contagiosum was the predominant diagnosis among infectious entities (N = 3), while acroangiodermatitis was the sole diagnosis reported in the vascular category (N = 1).

CONCLUSIONS

These findings confirm rosettes are not specific to keratinocytic growths and are observed in a wide range of conditions. Knowledge of the breadth of conditions with rosettes may aid clinicians when developing a differential diagnosis of a growth or an eruption with rosettes under dermoscopy.

Efficacy evaluation and dermoscopy predictors of photodynamic therapy with different pretreatments in the treatment of actinic keratosis

OBJECTIVE

The aim of this study was to accurately evaluate the efficacy of photodynamic therapy (PDT) on actinic keratosis (AK) in the Asian population and its relationship with preconditioning and dermoscopy grading, and to determine whether some dermoscopic features of AK can independently predict the response to PDT to optimize the choice of clinical treatment.

MATERIALS AND METHODS

From January 2017 to January 2020, patients who were diagnosed as AK with only one lesion in our hospital were included in our study. PDT was performed after pretreatment with ablative fractional CO2 laser or cryotherapy. Logistic regression analysis was used to evaluate the characteristics of dermoscopy to determine the independent predictors of efficacy.

RESULTS

A total of 95 patients were enrolled in the study, and the final clinical evaluation was 92 cases (96.8%) as complete remission and 3 cases (3.2%) as partial remission/no response. Dermoscopy showed complete remission in 77 cases (81.1%) and partial remission/no response in 18 cases (18.9%). No significant difference was observed in the complete remission rate of dermoscopy grade 1 lesion after laser or cryotherapy pretreatment (p > 0.05), but for dermoscopy grade 2 and grade 3 lesions, the complete remission rate (dermoscopy evaluation) of the cryotherapy pretreatment group was higher than that of laser group (p < 0.05). The probability of complete remission with red pseudonetwork at the T0 time point increased by 3.8 times (odds ratio [OR] = 3.870,95%confidence interval [CI]:1.077-13.912, p = 0.048), while the probability of complete response for lesions with slight erosion at the baseline decreased by 85% (OR = 0.150,95%CI:0.033-0.671, p = 0.013).

CONCLUSION

For dermoscopy grade 2 and 3 lesions, PDT after pretreatment with cryotherapy is more effective. Dermoscopy pseudo-reticular structure and microscopic erosions were independent predictors of PDT efficacy. These findings may help clinicians to better select patients with AK for PDT.

Evaluation of relationship between antihypertensive drug usage and dermatoscopic features in patients with keratinizing skin cancer

Keratinizing skin cancers including actinic keratoses (AK), in situ squamous cell carcinoma/Bowen's disease/intraepidermal carcinoma (IEC), invasive cutaneous squamous cell carcinoma (cSCC) and keratoacanthoma share similar dermatoscopic features and also reveal different patterns that assist in their diagnosis. Recently epidemiological studies reveal the association between antihypertensive drugs and skin cancer risk, especially cSCC. This study aims to determine the dermatoscopic features of keratinizing skin cancer in patients using antihypertensive drug and compare with non-users. A total of 46 patients with 64 keratinizing skin cancer lesions were included in the study. The demographic, clinical characteristic of patients, the number, duration, localization and dermatoscopic features from each lesion were collected. First, we evaluated the dermatoscopic features according to the histopathologic diagnosis. Then, all patients were divided into two groups as users of antihypertensive drugs and non-users. The dermatoscopic features were compared in terms of antihypertensive drug usage and histopathologic diagnosis in antihypertensive drug users and non-users, separately. The users of anti-hypertensive drugs were 22 (47,8%) and non-users 24 (52,2%). Of the total 64 lesions including 47 AK, 5 IEC, 10 cSCC, and 2 keratoacanthoma were evaluated. White structureless area was found statistically significant in cSCC lesions of patients using antihypertensive drugs (P = .004). This finding in cSCC may be a clue for antihypertensive drug usage and these drugs may be a predisposan factor for dermal fibrosis. Regardless of histopathology, dermatoscopic features show no statistically difference between antihypertensive drug users and non-users (P > .05). Clearer results can be obtained by conducting more detailed and long-term studies.

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.

Dermatoscopic features of pigmented intraepidermal carcinoma on the head and neck

BACKGROUND AND OBJECTIVE

Pigmented intraepidermal carcinoma is characterized by dermatoscopic dots and structureless areas, including dots in linear arrangement and by coiled vessels. There are no studies describing the dermatoscopic features of pigmented intraepidermal carcinoma on the head and neck. We aim to characterize the clinical and dermatoscopic appearance of this entity.

PATIENTS AND METHODS

We retrospectively analyzed 79 cases of pigmented intraepidermal carcinoma on the head and neck.

RESULTS

Pigmented intraepidermal carcinoma on the head and neck was characterized dermatoscopically by multiple colors (98.7 %, n = 78), pigmented circles (48.1 %, n = 38), white circles (17.7 %, n = 14), angulated lines (41.8 %, n = 33) and structureless areas (86.1 %, n = 68). Dots in linear arrangement were present in 13.9 % (n = 11). Coiled vessels were present in 7.6 % (n = 6), the dominant vessel type being prominent serpentine vessels (29.2 %, n = 23), thicker and/or redder in color than surrounding vessels, most being in the angular arrangement of the dermal plexus (24.1 %, n = 19).

CONCLUSIONS

Pigmented intraepidermal carcinoma on the head and neck differs from current published descriptions of pigmented intraepidermal carcinoma, reaching statistical significance with a lower incidence of coiled vessels and a higher incidence of pigmented circles, with evident similarities to pigmented actinic keratosis at that location.