The investigators hypothesis is that secondary causes of bone loss are prevalent in patients with breast and prostate cancer, and those patients with secondary causes of bone loss are at higher risk for treatment related bone loss. The goals of this pilot study are to estimate the prevalence of secondary causes of osteoporosis in a cohort of patients with nonmetastatic breast and prostate cancer with osteopenia and osteoporosis.

The interaction of aging, cancer, and bone loss is poorly understood. Cancer or cancer therapy could potentially accelerate bone loss and increase the risk for osteopenia or osteoporosis. The hypothesis of this observational study is that secondary causes of bone loss are prevalent in patients with breast and prostate cancer who are high risk for treatment related bone loss. In order to test this hypothesis, this prospective pilot study will systematically evaluate secondary causes of bone loss in a cohort of patients with nonmetastatic breast and prostate cancer with osteopenia/osteoporosis.

1. Identify patients with nonmetastatic breast cancer newly diagnosed with osteopenia/osteoporosis (Dual Energy X-ray Absorptiometry Bone Density scan T-score average between hip (femoral neck) and spine (L1-L4) of less than -1.0 to -2.5/ less than -2.5, respectively).
2. Identify patients with nonmetastatic prostate cancer newly diagnosed with osteopenia/osteoporosis (Dual Energy X-ray Absorptiometry Bone Density scan T-score average between hip (femoral neck) and spine (L1-L4) of less than -1.0 to -2.5/ less than -2.5, respectively).
3. Refer patient to City of Hope Endocrinology Osteoporosis Clinic.
4. Approach patient in consecutive order in which they have been referred to Endocrinology Osteoporosis Clinic.
5. Describe the study to the patient: patient consents or refuses.
6. Once consented, the patient's medical records are reviewed and Dual Energy X-ray Absorptiometry Bone Density reports are obtained from City of Hope records or the screening medical institution records to confirm diagnosis of osteopenia/osteoporosis or normal bone health.
7. Study participants will undergo an evaluation for secondary causes of bone per standard of care with patient questionnaires.
8. Furthermore, laboratory tests that support secondary causes of bone loss will be retrospectively collected via chart review.

Inclusion Criteria

1. Diagnosis of nonmetastatic breast cancer or diagnosis of nonmetastatic prostate cancer
2. Measurement of bone mineral density by Dual Energy X-ray Absorptiometry (DEXA) within 6 months of enrollment into study.
3. Patients of all ages are eligible but need to qualify for standard DEXA screening
4. Patients of all performance status are eligible
5. Patients are able to give informed consent

Exclusion Criteria

1. Patients previously diagnosed or treated for osteoporosis/osteopenia
2. Stage IV cancer

Adults with newly diagnosed osteopenia and osteoporosis with diagnosis of non-metastatic breast or prostate cancer