Vitamin D, Leptin, Vitamin D Receptor Polymorphism, and Treatment-Related Morbidity in Ovarian Cancer

Inclusion Criteria: * Patients must have a histologic diagnosis of ovarian, fallopian tube, or primary peritoneal carcinoma per pre-treatment biopsies by laparoscopy, or interventional radiology, paracentesis, or CT guided core biopsy. Histologic documentation of the original primary tumor is required via the pathology report. * Patients must have adequate: Renal function: Glomerular Filtration Rate (GFR) \> 30; Gastrointestinal absorption: No underlying malabsorption syndrome (i.e. inflammatory bowel disease, celiac disease) * Ability to tolerate oral medication * Patients taking vitamin D at the time of enrollment without a diagnosis of vitamin D deficiency * Patients of childbearing potential must have a negative pregnancy test prior to the study entry and be practicing an effective form of contraception. * If applicable, patients must discontinue breastfeeding prior to study entry. * Patients must be at least 18 years old Exclusion Criteria: * Patients with a known pre-existing diagnosis of vitamin D deficiency. * Patients with renal disease and a GFR \<30 * Patients with primary hyperparathyroidism * Patients with other invasive malignancies, with the exception of nonmelanoma skin cancer. * Patients with concomitant endometrial cancer diagnosed at the time of their ovarian cancer are allowed to participate if the endometrial cancer is International Federation of Gynecology and Obstetrics stage 1B or less. * Patients of childbearing potential, not practicing adequate contraception, patients who are pregnant, or patients who are breastfeeding are not eligible for this trial.