The purpose of this research is to investigate whether patients who previously had endoprosthesis surgery experience memory, thinking, or heart problems. It will also help determine how often these problems occur.

At your first visit you will be asked to do the following:

1. Sign the consent document.
2. Patient Interview: An interview will be conducted by the study coordinator on the research team. They will ask your past surgical history, health history, medications, and your cognition.
3. Informant Interview: A close friend, spouse of relative of you will be interviewed about your day-day cognition.
4. Memory Interview: You will be evaluated on your memory and thinking skills three total times. One to determine baseline, and then repeated at one year and two years. You will answer questions that evaluate various thinking abilities such as concentration, memory, reasoning, and learning.
5. Blood Draw: You will have a blood draw three times (4.2-5 tablespoons) to determine your baseline, 1 year, and 2 year research results.

6: Echocardiogram: You will be asked to have three echocardiograms. One to determine baseline, and then repeated at one year and two years.

Inclusion Criteria:

• Patient has an endoprosthesis after extremity malignancy

Exclusion Criteria:

• Current fracture or infection around the endoprosthesis
• Patient is pregnant

150 patients to complete cardiology part of the study (questionnaires, blood test, echocardiogram).

150 patients to complete cognitive part of the study (questionnaires, interviews, blood test).

Patient groups may overlap.