Inclusion Criteria:

   - Patients with histologically or cytologically confirmed locally advanced breast cancer
   that is refractory to chemotherapy or other therapeutic agents or with a history of
   breast cancer with new evidence of a local recurrence (defined as a chest wall or
   breast recurrence and/or nodal recurrence); the diagnosis will be made based on
   clinical and pathologic features

   - Patients must be >18 years of age.

   - Karnofsky Performance Status (KPS) score > 70

   - Patts must have normal organ function as defined below:

      - total bilirubin < 1.5 x institutional upper limit of normal

      - AST(SGOT)/ALT(SGPT) < 2.5 x institutional upper limit of normal

      - creatinine < 1.5 x institutional upper limit of normal

   - Patients must have left-ventricular ejection fraction > 50% at baseline.

Exclusion Criteria:

   - Patients who have contraindications to radiotherapy, such as scleroderma,
   dermatomyositis, or severe cutaneous manifestations of systemic lupus erythematosus
   (SLE)

   - History of allergic reactions attributed to compounds of similar chemical or biologic
   composition to lapatinib

   - Uncontrolled intercurrent illness including, but not limited to, ongoing or active
   infection, symptomatic congestive heart failure, or psychiatric illness/social
   situations that would limit compliance with study requirements

   - Women who are pregnant or lactating, as well as women of child-bearing potential who
   are unwilling or unable to use an acceptable method of birth control to avoid
   pregnancy for the duration of the study