EGF and renal cell carcinoma: Similarly, renal cell carcinomas that metastasize to the bone present as osteolytic lesions in the pelvis, ribs, and spine [17], Conversely, prostate cancer bone metastases exhibit sclerotic bone upon radiographic analysis, suggesting an overtly osteoblastic process (though resorption plays a role as well) [18] fueled by bone morphogenic protein (BMP), epidermal growth factor (EGF), and platelet-derived growth factor (PDGF) [19,20].