This is a phase II placebo-controlled intervention trial assessing aspirin (ASA) as a UV protectant in patients at risk for melanoma.

While melanoma risk is largely genetically determined, exposure to ultraviolet (UV) radiation in sunlight is the major environmental risk factor. Although sunscreen use can reduce melanoma risk 2-fold, its efficacy has been questioned, and most patients do not apply sunscreens properly.

This study will evaluate the downstream effects of aspirin (ASA) in human blood and skin moles (nevi) following oral ingestion. We will determine if chronic ingestion of ASA can modulate UV-sensitivity of the skin, UV-induced damage in nevi, and PGE2 levels in blood and nevi.

Inclusion Criteria:

• Must have at least 2 nevi (each >5 mm diameter) not clinically suspicious for melanoma that can be biopsied.
• Must be older than age 18.
• Must be able to receive informed consent and sign an approved consent form that conforms to federal and institutional guidelines.

Exclusion Criteria:

• The patient cannot speak / understand English or Spanish.
• The patient is pregnant or breastfeeding.
• The patient is a prisoner, critically or mentally ill, or otherwise incapacitated or considered vulnerable.
• The patient has history of allergic reaction to ASA.
• The patient has history of severe asthma.
• The patient has been taking ASA or any NSAID in the past 2 weeks.
• The patient has been taking a blood thinner in the past 2 weeks.
• The patient has history of bleeding disorder.
• The patient has history of peptic ulcer disease.
• The patient has had recent intense UV exposure in the past month.