We investigated the eventual diagnosis in patients referred to a tertiary centre with a possible diagnosis of a primary bone malignancy. We reviewed our database from between 1986 and 2010, during which time 5922 patients referred with a suspicious bone lesion had a confirmed diagnosis. This included bone sarcoma in 2205 patients (37%), benign bone tumour in 1309 (22%), orthopaedic conditions in 992 (17%), metastatic disease in 533 (9%), infection in 289 (5%) and haematological disease in 303 (5%). There was a similar frequency of all diagnoses at different ages except for metastatic disease. Only 0.6% of patients (17 of 2913) under the age of 35 years had metastatic disease compared with 17.1% (516 of 3009) of those over 35 years (p < 0.0001). Of the 17 patients under 35 years with metastatic disease, only four presented with an isolated lesion, had no past history of cancer and were systematically well. Patients under the age of 35 years should have suitable focal imaging (plain radiography, CT or MRI) and simple systemic studies (blood tests and chest radiography). Reduction of the time to biopsy can be achieved by avoiding an unnecessary investigation for a primary tumour to rule out metastatic disease