Malignant bone tumours of the foot

INTRODUCTION Malignant osseous foot tumours are uncommon. Their oncological outcomes have been poorly documented in the literature so far. The aim of this study was to establish the incidence and to evaluate the oncological outcomes of such patients. METHODS Our large orthopaedic oncology database was used to review 70 malignant osseous foot tumour patients. RESULTS The age at diagnosis of malignant osseous foot tumours demonstrated a bimodal distribution peaking in the second and eighth decades of life. Overall, 55 primary malignant bone tumours of the foot (79%) were identified. The median duration from onset of symptoms to diagnosis was 52 weeks (interquartile range [IQR]: 17-104). Eight primary tumours (15%) underwent an accidental excision (ie intralesional excision of a malignant bone tumour where some of the tumour has been left behind, also known as a 'whoops procedure') prior to referral to our unit. Forty-six patients (84%) underwent surgery overall and thirteen of these developed recurrence or metastases. Seven of eight patients with a previous accidental excision underwent amputation. Fifteen osseous metastatic foot lesions were identified. The median length of foot symptoms to diagnosis was 24 weeks (IQR: 20-36 weeks). The median time to death following diagnosis of osseous foot metastases was 20.1 months (IQR: 11.3-27.8 months). CONCLUSIONS A high index of suspicion and awareness of clinical features of malignant osseous foot tumours are both essential to avoid diagnostic delays. Amputation is associated with a respectable outcome for patients who have undergone previous accidental excisions.