Amanda, I'm 28 and just went through surgery to have a nodular malignant melanoma removed off my leg. It was 1.6 mm thick, and just like other posters, had a sentinal lymph node biopsy done. The doctors were looking for which lymph nodes the cancer might have spread to, if it had. Since my melanoma was on my leg, the closest lymph nodes were in my groin. So, on the day of my surgery, they removed a small section of my leg around the melanoma (down to the muscle) and then biopsied 4 lymph nodes in my groin. My leg is healed very well and the cancer had not spread anywhere!
At first I had a hard time getting anyone to tell me the chances of this cancer spreading to my lymph nodes. I was very scared and was thinking that it had DEFINITELY spread, since no one would give me any numbers. But then my surgeon gave me a rough estimate and I felt much better about my chances. I guess I just let my imagination run wild, and it got away from me. I kept looking at my 2-year old and worrying about things I might miss.
I was actually misdiagnosed over a year ago. I asked a general practioner to remove this "thing" off my leg because I wasn't sure what it was. She told me it was scar tissue from me probably shaving off a mole. I knew I never had a mole there, but she was the expert, right, and if it was just scar tissue......well, my son (being a curious 2-year old) would always press on this "thing" on mommy's leg everytime I would wear shorts or a skirt. This past fall I finally called a dermatologist out of the phone book to have another opinion about it. He biopsied it, and it was a nodular malignant melanoma. What had me so worried after I heard all of this was that it had been on my leg ever since I was pregnant. (Going on 3 years), And I just thought to myself, "It has surely spread by now."
My point to you is this, you don't know what miracles are in store for you. Write down any questions you have for your doctors, get second opinions, listen to your inner self, and be thankful for each day!