Sunitinib monotherapy in a patient with primary breast cancer

Sunitinib is an oral multi-targeted tyrosine kinase inhibitor approved for use in patients with advanced renal cell carcinoma (RCC). However, despite its preclinical biological effect on breast cancer, it is yet to be proven effective for clinical use in patients with breast cancer. The present report describes a case of a 69-year-old woman with advanced clear-cell RCC and a luminal B subtype invasive ductal carcinoma of the right breast that showed a partial response to monotherapy with sunitinib. This is the first report of the effect of sunitinib monotherapy in a patient with early-stage breast cancer.