The diagnosis of cancer can be made only after a careful clinical examination and several laboratory tests ate required  to accurately know the primary site of origin of cancer, type of cancer and to learn the extent of spread of the disease.These are necessary for planning effective treatment. Identifying cancer cells with the help of a microscope in an aspirate of body issue or scrapings of fluids aspirated by a needle and syringe is called cytology. The examination of a piece of body tissue after processing is called biopsy and histopathology examination. Endoscopes passed in to the body are used to diagnose cancer of deep seated internal organs like oesophagus, stomach, intestines, thoracic and abdominal cavities. For diagnosing leukamia, blood examination is essential. Plain X-ray pictures are used to diagnose cancers of bone. Some times special X-rays like Barium X-rays, angiograms etc. are taken. Ultrasound scanning, CT scanning, NMR scanning and scanning by radio isotopes are also used depending the site of cancer. Certain biochemical tests are undertaken to diagnose mulriple myeloma. Generally, the doctor will do two or three tests for a suspected cancer.