Over 17-month complete clinical brain response with a well-tolerated lapatinib plus capecitabine combination in a very young patient afflicted by HER2-positive metastatic breast cancer.

This report describes a case of ab initio metastatic HER2-positive breast cancer in a very young patient. The onset of breast cancer at such a young age is uncommon and could delay the diagnosis with unquestionable impact on the prognosis. Unfortunately, the patient experienced cerebral progression during first-line treatment. Indeed, brain metastases occur in about one-third of HER2-positive metastatic breast cancer patients during trastuzumab-based treatment. The small molecule lapatinib is active in established cerebral disease, and we report a complete brain response longer than expected, thanks to a well-tolerated, orally administered combination of lapatinib and capecitabine.