Double primary malignancies could be divided into two categories, depending on the interval between tumor diagnoses. A secondary malignancy could be defined as a new cancer that has occurred as a result of previous treatment with radiation or chemotherapy. Second primary malignancy can occur at any age but it's commonly at old age. A 46 premenopausal female patient presented to our outpatient clinic complaining from a mass in her right breast, routine metastatic work-up for distant metastasis declared multiple hepatic metastases, RT renal mass, and bone metastases. Palliative radiotherapy to tender and weight bearing sites followed by 4 cycles of systemic chemotherapy FEC regimen were received. Tru-cut needle biopsy from renal mass detected renal cell carcinoma of clear cell type, the patient started sunitinib and tamoxifen with bisphosphonate (Zoledronic acid), assessment of the response revealed reduction of the size and number of HFLs, and the size of renal mass, so the patient was decided to do cytoreductive nephrectomy and then continued on TAM and sunitinib. Collectively, due to the rising incidence of multiple primary malignancies, further studies should be done not only for better clinical evaluation and treatments but also for accurate determination of possible causes, pathogenesis, effective managements and screening programs.