Nodular melanoma (NM) is a subtype of skin cancer accounting for about 15% to 20% of all melanoma diagnoses. It is the second most common type, yet it contributes to a disproportionately high percentage of melanoma-related deaths due to its rapid progression. This aggressive nature makes early identification crucial, as the survival rate depends heavily on how quickly the lesion is diagnosed and treated. Understanding the specific signs of NM is necessary because it often presents differently than the more common, superficial types of melanoma.
The Question of Pain and Other Sensations
Nodular melanoma lesions are not always painful, especially in the early stages, but the absence of pain should not be mistaken for the absence of danger. When symptoms related to sensation do occur, they often signal deeper invasion, including tenderness, stinging, or persistent itching (pruritus).
Patients with thicker melanomas are more likely to report symptoms like itching and bleeding. As the tumor grows and its surface becomes fragile, it may begin to bleed, ooze, or develop an open sore (ulcerate) that does not heal.
Recognizing the Distinct Visual Markers
Nodular melanoma often does not conform to the traditional ABCDE rules—Asymmetry, Border irregularity, Color variation, Diameter, and Evolving—used for other melanomas. Instead, dermatologists emphasize the EFG rule to help identify this specific subtype: Elevation, Firmness, and Growth. The lesion is almost always raised above the surrounding skin surface, giving it a dome-shaped or nodular appearance.
The color of nodular melanoma can be highly variable and sometimes misleading. While many are black or blue-black, up to 50% are amelanotic, meaning they lack pigment and appear pink, red, or even skin-colored. The growth feels solid and hard when gently touched, and its surface can range from smooth and shiny to rough, crusted, or warty.
Understanding the Aggressive Growth Rate
The most dangerous characteristic of nodular melanoma is its intrinsic vertical growth pattern. Unlike superficial spreading melanoma, which grows horizontally across the top layers of the skin, NM immediately begins to penetrate downward into the dermis, allowing the lesion to grow noticeably over just a few weeks or months.
This vertical growth phase is measured by the Breslow thickness, which is the depth of the tumor in millimeters from the top layer of the skin to the deepest point of cancer cell involvement. Breslow thickness is the primary factor for predicting the outcome of the disease; the thicker the tumor, the greater the risk of the cancer spreading (metastasis). Because NM grows vertically from the start, it is frequently diagnosed when the Breslow thickness is already substantial.
When to Seek Urgent Medical Attention
Any new or changing spot on the skin that exhibits the EFG characteristics—Elevated, Firm, and Growing—should be evaluated by a healthcare professional immediately. This urgency is paramount due to the cancer’s rapid vertical growth into deeper skin layers.
If a growth on your skin is firm, dome-shaped, changes quickly in size or shape, or starts to itch, bleed, or ooze, contact a dermatologist or primary care physician immediately. Observing a spot that is evolving in color, texture, or sensation requires prompt action.