Natural History Study of Fungal Infections of the Blood in Patients With Cancer or in Patients Who Have Undergone a Stem Cell Transplant

RATIONALE: Gathering information about how often fungal infections of the blood occur in patients with cancer or in patients who have undergone stem cell transplant may help doctors learn more about the disease.
PURPOSE: This natural history study is collecting information about fungal infections of the blood over time from patients with cancer or from patients who have undergone a stem cell transplant.