A darkening nodule

Symptoms
Related diseases

A darkening nodule is a raised area on the skin that changes color over time, often becoming darker than the surrounding skin. This change in pigmentation can occur gradually or more rapidly and may signal a variety of underlying conditions. Characteristics of a darkening nodule include:

  • Color Change: The nodule may initially be light-colored and darken to brown, black, or another deep hue.
  • Elevation: The nodule is typically raised above the surface of the skin.
  • Texture: It may have a smooth, rough, or uneven texture.
  • Symptoms: While some darkening nodules are asymptomatic, others may cause itching, tenderness, or discomfort.

Possible Causes

  1. Seborrheic Keratosis: Often starts light brown and darkens over time. These nodules have a “stuck-on” appearance.
  2. Melanoma: A type of skin cancer characterized by asymmetric darkening, irregular borders, and pigmentation.
  3. Benign Pigmented Lesions: Such as moles (nevi) that can darken with age or sun exposure.
  4. Post-Inflammatory Hyperpigmentation: Darkening of the skin following trauma, inflammation, or skin conditions.
  5. Dermatofibromas: Benign skin nodules that may darken over time.

Source | Author Doctor Nikas Samuolis, reviewed by Prof. Virginijus Šapoka | Vilnius University | Faculty of Medicine | Head of the Department of Internal Medicine, Family Medicine, and Oncology