Western Nevada College's Melanie Pfeiffer is known for her fight and determination on the softball field.Now, the sophomore player potentially faces her biggest fight - for her life. On April 20, Pfeiffer was diagnosed with melanoma, an often lethal form of skin cancer.So now, at the time of year when most students' thoughts turn toward free-spirited fun and decompression, Melanie's mind is suddenly focused on her own mortality and the inescapable reality of surgery this Friday. It's a lot for anybody to deal with, let alone a sophomore in college, but Pfeiffer has high hopes that she will beat the …