Dermoscopic features of squamous cell carcinoma on the lips

Clinical and dermatoscopic predictors of squamous cell carcinoma of the lips: a case-control, multicentric study

BACKGROUND

Squamous cell carcinoma of the lip accounts for 20% of all oral carcinomas. Its diagnosis may be challenging because it clinically resembles actinic cheilitis and inflammatory lesions of the lips.

OBJECTIVES

To determine clinical and dermatoscopic predictors of squamous cell carcinoma of the lip vs. other lip lesions.

METHODS

Multicentre retrospective morphological study, including histologically confirmed cases of squamous cell carcinoma of the lip and controls consisting of actinic cheilitis and inflammatory lesions of the lips. Clinical and dermatoscopic images were evaluated for the presence of predefined criteria. Crude and adjusted odds ratios and corresponding 95% confidence intervals were calculated by univariate and multivariate logistic regression respectively.

RESULTS

A total of 177 lip lesions were evaluated, 107 (60.5%) were squamous cell carcinomas and 70 (39.5%) were controls. The most frequent dermatoscopic criteria of lip squamous cell carcinoma were scales (100%), white halos (87.3%) and ulceration (79.4%). The majority of squamous cell carcinomas displayed polymorphic vessels (60.8%), with linear (68.6%) and hairpin (67.6%) being the most frequent types. Multivariate logistic regression analysis showed that clinical predictors of lip squamous cell carcinoma were exophytic appearance and clinical hyperkeratosis, with 43-fold and 6-fold higher probability respectively. White clods and ulceration in dermoscopy presented a 6-fold and 4-fold increased risk for squamous cell carcinoma respectively.

CONCLUSIONS

A scaly lesion with exophytic growth, dermatoscopically displaying white clods, ulceration and linear and hairpin vessels is very likely a squamous cell carcinoma of the lip.

Mucoscopy of lip squamous cell carcinoma and correlation with skin phototype and histological differentiation: a multicentric retrospective observational study by the International Dermoscopy Society

BACKGROUND

There is a scarcity of published data on the dermoscopic morphology of lip squamous cell carcinoma (SCC) and its variability according to the histological differentiation degree and patient's ethnicity as per skin phototype.

OBJECTIVES

To evaluate the dermoscopic features of SCC of the lips and identify possible dermoscopic clues that may aid in differentiation between well-differentiated, moderately-differentiated, and poorly-differentiated lesions, as well as between "fair" skin (Fitzpatrick skin phototypes I-III) and "dark" skin (Fitzpatrick skin phototypes IV-VI).

METHODS

The clinical profile and dermoscopic images of patients of any age and either gender with histologically confirmed lip SCC collated from seven dermatological centers were retrospectively evaluated for dermoscopic clues as per certain predefined criteria.

RESULTS

A total of 60 lesions from 60 patients were included in the analysis. Histologically, well, moderate, and poordifferentiation were seen in 24 (40%), 14 (23.3%), and 22 (36.7%) of the lesions, respectively. Other than the presence of brown-to-gray dots/globules, which was exclusively seen in cases with dark phototypes (19.4% P = 0.035), no other dermoscopic feature was statistically significant in differentiating between the two skin types. Some dermoscopic findings were observed specifically with statistical significance: perivascular white halos (P = 0.049) and whitish-yellow background in well-differentiated lesions (P = 0.003); pink background in moderately-differentiated lesions (P = 0.003); and red background with dense vascularity in poorly-differentiated lesions (P < 0.001).

CONCLUSIONS

The presence of vessels, scale/crust, and keratinization-associated white structures were the most common dermoscopic clues in lip SCC.

Dermatologist-level classification of malignant lip diseases using a deep convolutional neural network

BACKGROUND

Deep convolutional neural networks (DCNNs) can classify skin diseases at a level equivalent to a dermatologist, but their performance in specific areas requires further research.

OBJECTIVE

To evaluate the performance of a trained DCNN-based algorithm in classifying benign and malignant lip diseases.

METHODS

A training set of 1629 images (743 malignant, 886 benign) was used with Inception-Resnet-V2. Performance was evaluated using another set of 344 images and 281 images from other hospitals. Classifications by 44 participants (six board-certified dermatologists, 12 dermatology residents, nine medical doctors not specialized in dermatology and 17 medical students) were used for comparison.

RESULTS

The outcomes based on the area under curve, sensitivity and specificity were 0·827 [95% confidence interval (CI) 0·782-0·873], 0·755 (95% CI 0·673-0·827) and 0·803 (95% CI 0·752-0·855), respectively, for the set of 344 images; and 0·774 (95% CI 0·699-0·849), 0·702 (95% CI 0·579-0·808) and 0·759 (95% CI 0·701-0·813), respectively, for the set of 281 images. The DCNN was equivalent to the dermatologists and superior to the nondermatologists in classifying malignancy. After referencing the DCNN result, the mean ± SD Youden index increased significantly for nondermatologists, from 0·201 ± 0·156 to 0·322 ± 0·141 (P < 0·001).

CONCLUSIONS

DCNNs can classify lip diseases at a level similar to dermatologists. This will help unskilled physicians discriminate between benign and malignant lip diseases. What's already known about this topic? Deep convolutional neural networks (DCNNs) can classify malignant and benign skin diseases at a level equivalent to dermatologists. The lips are a unique feature in terms of histology and morphology. Previous studies of DCNNs have not investigated tumours on specific locations. What does this study add? This study shows that DCNNs can distinguish rare malignant and benign lip disorders at the same rate as dermatologists. DCNNs can help nondermatologists to distinguish malignant lip diseases. What are the clinical implications of this work? DCNNs can distinguish malignant and benign skin diseases even at specific locations such as the lips, as well as board-certified dermatologists. Malignant lip diseases are rare and difficult for less trained doctors to differentiate them from benign lesions. This study shows that in dermatology, DCNN can help improve decision-making processes for rare skin diseases in specific areas of the body.

Dermoscopic Features of Lower Lip Squamous Cell Carcinoma: A Descriptive Study

Aim

Dermoscopic features of cutaneous squamous cell carcinoma (SCC) have been well described; however, there are a few studies focused on the dermoscopic aspect of lip SCC. In this study, we aimed to identify dermoscopic findings of lower lip SCC.

Materials and Methods

The clinical and histopathologic features, dermoscopic images, and demographic data of the patients with histologically approved lip SCC were retrospectively evaluated.

Results

A total of 10 lesions were enrolled in the study. Milky red structureless background (100%) and keratin scale (100%) were present in all the lesions. Blood spots on thick keratin scale were observed in eight lesions. Seven lesions showed white structureless areas. Two lesions exhibited ulceration and one of the lesions had structureless brown pigmentation. The most common vascular pattern observed was polymorphous vascular pattern (60%).

Conclusion

White and milky red structureless areas, blood spots on thick keratin scale, and polymorphous vascular pattern are the main dermoscopic clues to lip SCC. The presence of these findings should direct the clinician to the possibility of SCC. The dermoscopic findings observed may also reflect histological grade of the lesion.

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.

Dermoscopy and reflectance confocal microscopy for monitoring the treatment of actinic cheilitis with ingenol mebutate gel: Report of three cases

Actinic cheilitis (AC) can precede the development of squamous cell carcinoma (SCC) of the lip, a location with higher risk of invasiveness and metastasis. Herein, we reported the use of ingenol mebutate (IngMeb) 0.015% gel on three consecutive days to treat three patients suffering from AC. All the three patients achieved complete clearance of AC with rapid clinical effect, favorable safety profile, good patient's compliance related to short time of applications, and few local skin reactions. So IngMeb is an attractive new therapy for AC. Moreover, the present case report adds further evidence to the usefulness of dermoscopy and Reflectance confocal microscopy (RCM) in the assessment and monitoring of treatment outcome.

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.