Lentigo – Full Medical Overview

Lentigo (plural: lentigines) is a small, sharply defined, flat, pigmented spot on the skin. It results from an increased number of melanocytes (pigment-producing cells) or increased melanin in the skin. Unlike freckles, lentigines do not fade in winter and can persist or grow over time.

🔍 Types of Lentigo:

1. Solar Lentigo (Actinic Lentigo or Age Spot)

   • Caused by chronic sun exposure

   • Common in older adults

   • Typically appears on the face, hands, shoulders, and arms

   • Light brown to dark brown color

2. Simple Lentigo (Lentigo Simplex)

   • Appears without sun exposure

   • Can occur at any age, even at birth

   • Not associated with any other skin condition

   • Usually smaller and darker

3. Lentigo Maligna

   • Precancerous lesion that can develop into melanoma

   • Occurs mostly in sun-exposed areas of elderly individuals

   • Has irregular borders and color variation

   • Requires monitoring or biopsy

🧬 Etymology:

• The term "lentigo" comes from Latin “lentil”, referencing the small, lentil-shaped appearance of the spots.

🧪 Causes and Risk Factors:

• Ultraviolet (UV) radiation (main cause of solar lentigo)

• Aging

• Genetic predisposition

• Light skin types (Fitzpatrick I–III)

• Tanning beds or frequent sunburns

👁️ Clinical Features:

⚠️ When to See a Doctor:

Seek medical attention if a spot:

• Grows quickly

• Changes shape or color

• Itches or bleeds

• Has irregular borders or multiple shades

Such features may indicate malignant transformation (e.g., melanoma).

🩺 Diagnosis:

• Usually clinical (visual examination)

• Dermatoscopy may help distinguish from other lesions

• Biopsy if malignancy is suspected

💊 Treatment Options:

🛡️ Prevention:

• Use sunscreen daily (SPF 30+)

• Avoid peak sun hours (10 AM – 4 PM)

• Wear protective clothing and hats

• Avoid tanning beds