Senile warts are harmless skin growths that appear most often in middle-aged and older adults. Their medical name is seborrheic keratoses, and they are the most common benign skin tumor. In an Australian study, 100% of adults over age 50 had at least one, and the median number of growths climbed to 69 per person in those over 75. Despite the name, they are not caused by a virus and are not contagious like true warts.
What They Look Like
The hallmark of a senile wart is its “stuck-on” appearance. The growth looks as though someone pressed a waxy, slightly raised patch onto the skin surface. Early lesions can be flat and faintly colored, but over time they typically become thicker and more textured, developing a rough, scaly surface you can feel with a fingertip.
Color ranges widely: light tan, yellow, grey, dark brown, or almost black. A single person can have growths of several different shades. Some people develop just one or two, while others accumulate dozens or even hundreds scattered across the chest, back, face, and shoulders. They range in size from a few millimeters to several centimeters across. In people with darker skin tones, a specific pattern of small, dark papules on the cheeks and forehead is common enough to have its own name: dermatosis papulosa nigra.
What Causes Them
Senile warts form when the outermost skin cells multiply faster than normal and pile up into a raised bump. Exactly why this overgrowth starts is not fully settled, but two factors consistently show up in research: age and cumulative sun exposure. Genetic analysis of these growths reveals a mutational fingerprint typical of UV damage, with the majority of DNA changes being the specific base swaps caused by ultraviolet light. Growths removed from the head and neck, areas of chronic sun exposure, carry the highest burden of these UV-signature mutations.
Heredity plays a role too. If your parents developed many seborrheic keratoses, you are more likely to as well. Still, plenty of growths appear on sun-protected skin, so UV exposure is clearly not the only trigger.
How They’re Identified
Most senile warts are diagnosed by appearance alone during a routine skin check. A dermatologist will look for the characteristic waxy, stuck-on texture and well-defined edges. When a growth is ambiguous, a handheld magnifying device called a dermatoscope can reveal telltale structures beneath the surface: tiny white cysts (which correspond to plugs of compacted skin protein) and small, dark, round openings on the surface. These features are distinctive enough to separate a senile wart from a mole or melanoma in the vast majority of cases.
If any doubt remains, a biopsy (removing a small piece or the entire growth for examination under a microscope) provides a definitive answer.
When a Sudden Outbreak Matters
One scenario deserves attention. A sudden eruption of many senile warts over a short period, especially if they itch, is known as the Leser-Trélat sign. This rare pattern has been linked to internal cancers, most often stomach, colon, or breast cancer, but also lymphoma and cancers of the pancreas, kidney, and lung. No strict diagnostic threshold exists for how many growths qualify, but the key feature is speed: a noticeable wave of new lesions appearing within weeks rather than the slow accumulation over years that is typical. If you notice a rapid crop of new growths, it is worth bringing up with your doctor promptly.
Removal Options
Because senile warts are benign, removal is optional. Most people seek it for cosmetic reasons or because a growth catches on clothing or jewelry and becomes irritated. Several methods are used.
- Freezing (cryotherapy): Liquid nitrogen is sprayed or dabbed onto the growth, causing it to blister and fall off over the following days. In clinical trials, over 90% of patients had no lasting side effects. The main risk is a lighter patch of skin (depigmentation) at the treatment site, which occurred in about 6% of cases.
- Scraping (curettage): After numbing the area, the growth is scraped off with a small, spoon-shaped instrument. This is often combined with light electrosurgery to stop bleeding and smooth the base. Atrophic scarring (a slightly indented scar) occurred in roughly 3% of electrosurgery cases in one clinical trial.
- Topical hydrogen peroxide: A prescription-strength 40% hydrogen peroxide solution was FDA-approved in 2017 for raised seborrheic keratoses. It is applied in-office, and a second treatment can follow about three weeks later if the growth hasn’t cleared. Clearance rates in clinical trials were modest: only 4 to 8% of patients saw all four treated lesions disappear completely, though 13 to 23% cleared at least three out of four.
Follow-up visits are typically scheduled at two weeks, one month, and three months after treatment to check healing and determine whether a repeat session is needed. Healing time varies by method, but most people can expect the treated area to look normal or near-normal within a few weeks to a couple of months.
Living With Senile Warts
New growths will likely continue to appear as you age, regardless of whether existing ones are removed. There is no proven way to prevent them, though limiting cumulative sun exposure may slow the rate of new ones based on the UV-damage evidence found in these lesions. They do not become cancerous, and having many of them does not raise your skin cancer risk. The growths are purely a cosmetic concern for most people, and many choose to leave them alone entirely.