Tehran University of Medical Sciences International Journal of Hematology-Oncology and Stem Cell Research 2008-2207 10 1 2016 04 08 56 60 EN Farhad Shahi Department of Hematology and Medical Oncology, Cancer Research Center, Cancer institute, Imam Khomeini Hospital Complex, Tehran University of Medical Science, Tehran, Iran Marziye Ghalamkari Internal Medicine Resident, Imam Khomeini Hospital Complex, Tehran University of Medical Science, Tehran, Iran Mehrzad Mirzania Department of Hematology and Medical Oncology, Cancer Research Center, Cancer institute, Imam Khomeini Hospital Complex, Tehran University of Medical Science, Tehran, Iran Mahdi Khatuni Internal Medicine Resident, Imam Khomeini Hospital Complex, Tehran University of Medical Science, Tehran, Iran 2015 10 11 2015 10 12  The coexistence of two malignancies is rarely seen. A little association between hematologic malignancies especially multiple myeloma and renal cell carcinoma has been reported in the recent past. Several case series revealed a bidirectional association between these two malignancies which may be due to the common risk factors, similar cytokine growth requirements and clinical presentation. Here, we aim to describe a patient who had multiple myeloma and in his work up renal cell carcinoma was found out incidentally. We would like to create awareness among clinicians for the coincidence of Renal cell carcinoma and Multiple myeloma. https://ijhoscr.tums.ac.ir/index.php/ijhoscr/article/view/347 https://ijhoscr.tums.ac.ir/index.php/ijhoscr/article/download/347/476