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Radioisotopes are used in diagnosing primary and metastatic bone tumours because of the high sensitivity. Diagnosing bone tumours using technetium methylene diphosphonate (Tc-99m MDP) on 9 randomly selected whole-body bone scans have been demonstrated by clinical studies of patients for illustrative review. Upon sati-sfactory testing of the e.cam® Single Photon Emission Computed Tomography at the Nuclear Medicine Depart-ment (Korle-Bu Teaching Hospital), scans of patients provided essential physiologic information about the sites of bone lesions and prognosis as shown by sequential changes in tracer uptake. The bone scintigrams were clas-sified either as normal or pathologic. Of the 197 patients (91 males and 106 females) who underwent radioacti-ve whole-body bone scans in the year 2006, the peak age at bone tumour detection was between 51 and 60 yea-rs. From qualitative analyses of the reported cases, 114 patients were diagnosed with bone tumours, but ~ 17 % were found to be primary, while ~ 83 % were metastatic in nature. The observation confirmed other published data that bone tumours with origin in the cells of bone are not prevalent compared to tumours that metastasize from other parts of the body, such as breast, cervix and prostate. Breast, prostate and cervical cancers contribut-ed respectively to 34 %, 19 % and 18 % of the bone tumour cases, but only 3 % were diagnosed with osteoporo-sis (a relatively rare type of bone disease).

3′-Fluoro-3′-deoxy-thymidine (FDT), a fluorinated analog of 3′-azido-thymidine (AZT), is both more active against the HIV virus but also more toxic than AZT. Because of its fluorine atom, it can be labeled with 18 F to be used to monitor this drug's biodistribution and targeting. A new synthesis for FDT, suited for 18 F labeling, has been developed. After protecting the 5′-hydroxy group with a trityl group, the 3′-hydroxy group was subtituted with a mesyl group in the lyxo configuration. Treatment with 18 F potassium fluoride and crown-18 ether yielded the 18 F-labeled fluoro derivative which on detritylation afforded 18 F FDT with 7% labeling efficiency. This is the first reported synthesis of 3′- fluoro-5′-O-trityl deoxythymidine using potassium fluoride and preparing its 18 F labeled analog. The time required to incorporate 18 F in the intermediate compound and isolate the end-product is reasonably short (approximately 2 h) which will allow sufficient time to conduct biological studies with this short-lived radionuclide.