This is an observational retrospective study where data will be collected from a medical claims database derived from a large national managed care organization with over five million members. Members enrolled in a Medicare supplement program will also be included. The objective of this study is to determine the incidence of cancer among patients who have used REGRANEX (becaplermin) compared to patients who have not used REGRANEX (becaplermin). REGRANEX (becaplermin) is an FDA-approved prescription medicine that contains a platelet-derived growth factor that is used for the treatment of foot ulcers in patients with diabetes. Patients who were treated with REGRANEX (becaplermin) between January 1998 and June 2003 will be identified in a health insurance claims database. Another group of patients who have not been treated with REGRANEX (becaplermin) but have similar characteristics to patients treated with REGRANEX (becaplermin) will also be identified during the same time frame in the database. Medical record abstraction and review will be conducted to verify all incident cancers identified. Follow-up for study outcomes will be conducted from the date of accrual through termination of health-plan membership or December 2003 (whichever comes first). The date of accrual is the date of REGRANEX (becaplermin) exposure for each exposed patient and his or her matched unexposed comparison patients. Any incidence of death from cancer will also be identified. The primary outcome measure in the study will be the incidence rate of cancers of all kinds, grouped by organ site in patients who have used REGRANEX (becaplermin) and patients who have not used REGRANEX (becaplermin). A secondary objective is a similar comparison of the incidence of death from cancer. This is an observational study; no investigational drug will be administered.