Investigation of Genetic Determinants of Capecitabine Toxicity

Inclusion criteria

• women with breast cancer in whom single agent capecitabine therapy is being considered
• aged 18 years and older

Exclusion criteria

• patients who have previously received capecitabine are excluded
• patients cannot be receiving capecitabine in combination with another cancer chemotherapy; concurrent use of trastuzumab is not permitted; concurrent use of zoledronic acid is allowed
• serum albumin less than 3.0 g/dL within the last 30 days
• creatinine clearance (CrCL) or glomerular filtration rate (GFR) less than 60 mL/min [/body surface area (BSA)] (within the last 30 days)
• inability to understand and give informed consent to participate
• patients with a history of inflammatory bowel disease requiring therapy or patients with chronic diarrhea syndromes or paralytic ileus
• patients with prior or concurrent pelvic irradiation
• patients who use an ostomy for fecal excretion
• there is no limit on the number of prior chemotherapies; the decision to use capecitabine is determined solely by the treating physician