Skin growths are common, and while many are harmless, distinguishing them can be challenging due to similar appearances. This article clarifies the differences between two common skin growths: verrucous keratosis and seborrheic keratosis, detailing their features and typical management.
Understanding Seborrheic Keratosis
Seborrheic keratosis (SK) is a common noncancerous skin growth, common with age, typically having a dull, waxy, or scaly surface with a characteristic “stuck-on” appearance. Their color varies widely, from light tan to brown, yellow, grey, or black. SKs can present as a flat or raised papule or plaque, from 1 mm to several centimeters. They are frequently found on the face, scalp, trunk, and in skin folds, but can appear anywhere except the palms, soles, and mucous membranes. While usually asymptomatic, some SKs may become itchy or painful if irritated.
Understanding Verrucous Keratosis
Verrucous keratosis (VK) is a skin growth that appears wart-like, characterized by a rough, elevated texture. These lesions vary in color from flesh-colored to reddish-brown. The surface feels firm and can be hyperkeratotic due to excessive keratin buildup. These growths can appear on the hands, feet, extremities, and sometimes in mucosal areas (e.g., oral, genital). While many verrucous keratoses are benign, some forms can be associated with human papillomavirus (HPV) infection.
Distinguishing Features and Clinical Presentation
Seborrheic and verrucous keratoses exhibit distinct features. Seborrheic keratoses are often described as having a “stuck-on” look, appearing as if easily scraped off. Their texture is typically waxy or somewhat crumbly, and they frequently display a greasy or soft feel. In terms of color, SKs are commonly brown, black, or light tan, and can sometimes have a mixed coloration.
Verrucous keratoses, in contrast, tend to have a rough, wart-like surface with a firm, papillomatous texture. They often appear raised from their inception, presenting with an irregular surface. The color of VKs is usually flesh-colored to light brown, sometimes appearing reddish. While SKs often start flat and then become raised, VKs are typically elevated from the outset.
The typical locations for these growths also differ. Seborrheic keratoses are very common on the trunk, face, and scalp, and can also be found on the neck, chest, and back. Verrucous keratoses are more commonly observed on the hands, feet, and other extremities, and may also appear on specific mucosal sites. Regarding onset, SKs are highly prevalent in middle-aged to older adults, with their numbers increasing with age. Verrucous keratoses, depending on their specific type, can manifest at various ages.
Diagnosis and Management
Healthcare professionals typically diagnose skin growths like seborrheic keratosis and verrucous keratosis through a thorough visual examination. Dermoscopy, a specialized magnifying tool, aids in revealing characteristic patterns and structures. If there is any uncertainty or suspicion of a more serious condition, a biopsy may be performed for a definitive diagnosis. This involves microscopic examination of a small sample.
Given the benign nature of most seborrheic keratoses, treatment is often not medically necessary unless they become irritated, itchy, or are a cosmetic concern. Common management approaches for both types of growths include observation. If removal is desired or indicated, methods such as cryotherapy (freezing the growth), shave excision (shaving off the lesion), or curettage (scraping the lesion away) can be used. It is advisable to consult a healthcare professional for any new, changing, or concerning skin lesions, as self-diagnosis is not recommended.