As people age, brown spots that are not natural freckles or birthmarks might begin to appear virtually anywhere on the body. The lips, too, can develop brown spots, although that's less common than such marks on the face, hands, chest and shoulders. Sometimes these spots on the lips are nothing more than benign lesions after sun exposure. But sometimes they are cause for concern, because these spots can imply more serious health conditions.
Significance and Identification
Brown spots on the lips, like any flat, dark marks that develop elsewhere on the body, must be examined by a physician, as they could be precancerous. Although they're usually just sun or liver spots that develop with age, there is no visible difference between precancerous and benign spots during the lesions' first stages. Brown spots on the lips can appear in a variety of ways: closer in toward the mouth or around the lip line, as a single spot or as multiple spots, freckle-size or larger, and light to deep in shading.
The root cause for brown spots on the lip is sun exposure. Ultraviolet rays penetrate the skin, including the lips, and UV damage might not show up until a few years after it occurs in the tissues below the surface. This is common for aging skin that has been overexposed to the sun, damaging the collagen protein. Sun exposure causes abnormal cell functioning, often leading to discoloration--a potential sign of more dangerous medical conditions.
Pregnancy is not a cause of brown spots on the lips; but it does make the spots darker.
Benign Brown Spots
The terms "age spots," "liver spots" and "sun spots" share the same meaning and frequently are used interchangeably. These flat, dark spots, like moles, have no significance to the skin or overall health. These benign spots can appear on lips that have a history of overexposure to UV rays. They are permanent, and they can increase in quantity over time.
Pre-Cancerous Brown Spots
Sometimes brown spots in the lips indicate a pre-cancerous condition technically called actinic cheilitis, often referred to as "farmer's lip" or "sailor's lip," which stems from excessive lifetime UV exposure. Most common on the lower lip, individuals with this condition not only have brown spots on the lips, but also complain of dryness and cracking. According to a report on this condition featured on SkinSight.com, actinic cheilitis is more common in older, fair-skinned men, particularly smokers. The same source reports that squamous cell carcinoma skin cancer develops in 6 percent to 10 percent of patients with actinic cheilitis.
Cancerous Brown Spots
Brown spots on the lips can indicate skin cancer. An estimated 3,500 new cases of skin cancer of the lips occur each year, and 90 percent of them are squamous cell carcinoma, according to an April 2008 MSNBC Health report, "Not just lip service: Gloss can invite skin cancer." If diagnosed in its early stages and treated properly, this form of cancer is not as serious as other types, according to the report. But left untreated, this carcinoma can cause lip disfigurement, and in rare cases it can spread and become deadly.
Oral malignant melanoma, though less common, is the more serious form of skin cancer that might first be identified by brown spots on the lips.
Patients concerned with brown spots on the lips should first consult a dermatologist. If the spots are simply age or sun spots, they may be treated with laser therapy, which will correct the discoloration and irregularity of the tissue to diminish the spot's appearance. If the brown spots indicate a more serious condition, follow the doctor's treatment path. In most cases, laser therapy is the preferred method.
The lips are especially sensitive to UV rays. The best way to protect them from sun is not only by applying sunscreen lip balms with a minimum SPF of 30, but by wearing lipstick with zinc oxide instead of lip gloss, Manhattan dermatologists Francesca Fusco and Bruce Robinson said in the MSNBC report. Wearing lip gloss (particularly high-shine) in the sun worsens UV penetration, according to Robinson.