The occurrence of multiple primary cancers is rare; it can be missed as a disease progression. The etiology remains controversial. We report a case of a 55-year-old female with metastatic renal cell carcinoma treated with sutent followed by left sided nephrectomy. Follow-up CT showed increase in the size of the right axillary lymph nodes which was proven after biopsy to be metastatic adenocarcinoma of the breast. Any suspicious disease progression in a single site not compatible with disease history should be biopsied for confirmation. The relationship between renal cell carcinoma and breast cancer is still unclear, and more case reports are required to determine this relationship.