How often do you look closely at your skin? A change in a mole or a sore that doesn't heal could be signs of skin cancer. 
Dr. Kimberly Kolar is a dermatologist with Skin Cancer and Dermatology Institute in Reno. If you have a question for her, call 858-2222 between 5 p.m. and 6 p.m. tonight.

1)  Let's start with moles... what should we look for - in terms of changes to the appearance?
If your mole or spot is any of the following, get it checked out: if the shape is asymmetrical, if the border is irregular or jagged, if the color is uneven, if the mole is larger than the size of a pea, if the mole has changed during the past few weeks or months.

2)  Are some people at higher risk than others for developing skin cancer?
Risk factors vary for different types of skin cancer. Some risk factors include: having lighter natural skin, people who have a family history of skin cancer, who are exposed to the sun more frequently than others, who have a history of sunburns - especially early in life and people who have a history of indoor tanning.

3)  The higher the SPF- the better?
An SPF 15 product blocks about 94% of UVB rays; an SPF 30 product blocks 97% of UVB rays; and an SPF 45 product blocks about 98% of rays. Experts recommend choosing a water-resistant sunscreen and re-applying every few hours.

4)  Many adults go to the tanning bed for a "base tan" before summer... bad idea?
Many medical professionals believe a base tan is not a safe tan.

5)  What about vitamin D and sun exposure... How much do you really need and is there a safe way to soak in the UV rays?
The sun is an excellent source of vitamin D, but it is hard to quantify how much vitamin D you get from time in the sun and the risk of skin cancer may outweigh the benefits. The major dietary source of vitamin D comes from fortified diary, along with some yogurts, cereals, fatty fish and fish liver oils.

For future questions, call the Skin Cancer and Dermatology Institute at 775-324-0699 or go to