Beyond Melanoma: Other Skin Conditions Diagnosed with Dermatoscope Views

I. Dermatoscopy for Non-Melanoma Skin Cancers

Dermatoscopy, also known as dermoscopy, has revolutionized the diagnosis of skin conditions beyond melanoma. While melanoma remains a primary focus, non-melanoma skin cancers such as Basal Cell Carcinoma (BCC) and Squamous Cell Carcinoma (SCC) can also be accurately identified using dermatoscope views. This non-invasive technique allows dermatologists to visualize subsurface skin structures that are not visible to the naked eye, improving diagnostic accuracy.

A. Basal Cell Carcinoma (BCC) Dermoscopic Features

Basal Cell Carcinoma (BCC) is the most common skin cancer worldwide, and dermatoscopy plays a crucial role in its early detection. Key dermoscopic features of BCC include:

• Arborizing telangiectasia: These are branching blood vessels that appear as fine, red lines.
• Blue-gray ovoid nests: These are irregularly shaped structures with a blue-gray hue.
• Ulceration: Often seen as a shiny, white to pink area.

In Hong Kong, BCC accounts for approximately 70% of non-melanoma skin cancers, making dermatoscopy an essential tool for early diagnosis and treatment.

B. Squamous Cell Carcinoma (SCC) Dermoscopic Features

Squamous Cell Carcinoma (SCC) is another common non-melanoma skin cancer that can be effectively diagnosed using dermatoscope views. Dermoscopic features of SCC include:

• Keratin masses: White or yellow amorphous structures.
• Blood spots: Irregular red dots or globules.
• White circles: These are indicative of keratinization.

In Hong Kong, SCC is less common than BCC but still accounts for about 20% of non-melanoma skin cancers. Early detection through dermatoscopy can significantly improve patient outcomes.

II. Diagnosing Benign Skin Conditions with Dermatoscopy

Dermatoscopy is not limited to malignant conditions; it is also invaluable for diagnosing benign skin conditions. By analyzing dermatoscope views, dermatologists can differentiate between benign and malignant lesions, reducing unnecessary biopsies.

A. Seborrheic Keratoses

Seborrheic keratoses are common benign skin lesions that can sometimes mimic melanoma. Dermoscopic features include:

• Comedo-like openings: These appear as small, black or brown dots.
• Milia-like cysts: Small, white or yellow round structures.
• Fissures and ridges: A "brain-like" or "cerebriform" pattern.

In Hong Kong, seborrheic keratoses are frequently seen in elderly patients, and dermatoscopy helps in distinguishing them from malignant lesions.

B. Warts (Verrucae)

Warts, or verrucae, are caused by the human papillomavirus (HPV). Dermatoscope views reveal:

• Red or black dots: These represent thrombosed capillaries.
• Finger-like projections: Common in plantar warts.

Woods lamps can also be used to detect warts, especially in cases where they are not easily visible to the naked eye.

C. Dermatofibromas

Dermatofibromas are benign fibrous nodules that often appear on the legs. Dermoscopic features include:

• Central white patch: A hallmark feature.
• Peripheral pigment network: A brownish ring around the lesion.

D. Hemangiomas

Hemangiomas are benign vascular tumors. Dermatoscope views show:

• Red lacunae: Well-demarcated, red to purple structures.
• Blue-white veil: In some cases.

III. Inflammatory Skin Conditions and Dermatoscopy

Dermatoscopy is increasingly being used to diagnose inflammatory skin conditions, providing insights that are not visible to the naked eye.

A. Psoriasis

Psoriasis is a chronic inflammatory skin condition. Dermoscopic features include:

• Red dots: Uniformly distributed.
• White scales: Often covering the entire lesion.

B. Eczema

Eczema, or atopic dermatitis, shows the following dermoscopic features:

• Yellow crusts: Indicative of exudation.
• Excoriations: Linear scratches.

C. Lichen Planus

Lichen planus is an inflammatory condition that affects the skin and mucous membranes. Dermoscopic features include:

• Wickham striae: White, lacy lines.
• Red dots: At the periphery.

IV. Hair and Nail Disorders: The Use of Dermatoscopy

Dermatoscopy is also useful for diagnosing hair and nail disorders, offering a non-invasive way to assess these structures.

A. Alopecia

Alopecia, or hair loss, can be evaluated using dermatoscope views. Key features include:

• Yellow dots: Seen in androgenetic alopecia.
• Black dots: Indicative of active disease.

B. Nail Infections

Nail infections, such as onychomycosis, can be diagnosed using dermatoscopy. Features include:

• Longitudinal striae: Seen in fungal infections.
• Spikes: At the distal edge of the nail.

C. Nail Tumors

Nail tumors, such as subungual melanoma, can be identified using dermatoscope views. Features include:

• Irregular pigmentation: A key indicator.
• Blood spots: Often present.

V. Conclusion: Expanding the Applications of Dermatoscopy

Dermatoscopy has expanded far beyond its initial use for melanoma diagnosis. Today, it is an indispensable tool for diagnosing a wide range of skin, hair, and nail conditions. From non-melanoma skin cancers to inflammatory conditions and benign lesions, dermatoscope views provide critical insights that improve diagnostic accuracy and patient outcomes. In Hong Kong, where skin cancer rates are rising, the adoption of dermatoscopy is more important than ever. Combined with other diagnostic tools like Woods lamps, dermatoscopy is paving the way for more precise and less invasive dermatological care.