Blood samples will be collected for research purposes. Planned studies include exploration of certain gene mutations and serum markers as predictors of response to ipilimumab treatment. Research lab studies will also evaluate if circulating tumor cells (CTC) can be accurately detected and isolated from the blood using novel laboratory techniques and if they are a prognostic/predictive marker for treatment response. Test results will not be given to participants or their physicians. In some cases, CTC may be grown for long-term cell lines for further research.