<prompt> Which of the following tumour is associated with raised serum alkaline phosphatase levels?OsteoclastomaOsteosarcomaMultiple myelomaChondrosarcoma  <response>: Serum alkaline phosphatase SAP It is generally elevated, but is of no diagnostic significance. It has been considered a useful parameter for follow up of a case of osteosarcoma. A rise of SAP after an initial fall after tumour removal is taken as an indicator of recurrence or metastasis. Reference: Maheshwari; Essential Ohopaedics; Page no: 240 