Secondaries are common in a/e -

Metastasis may occur in any bone but most commonly involve axial skeleton (e.g. vertebra, pelvis, ribs. skull, sternum) Proximal femur, and humerus in descending order. Red marrow in these areas are rich in capillary network, slow blood flow and nutrient environment facilitates the implantation and growth of the tumour cells. Metastasis in small bone of hand and feet are uncommon. Metastatic tumors are the most common form of skeletal malignancy.