Clinicopathological guide to malignant bone tumours: A retrospective analysis of the cancer registry at Kilimanjaro Christian Medical Centre in northern Tanzania

Background: Primary neoplasms of the skeleton are rare. This study aimed at determining the spectrum of different malignant bone tumours at a tertiary hospital cancer registry in the Northern Zone of Tanzania, along with related symptoms, clinical presentations, and clinical diagnosis accuracy (using histology as the standard).

Methods: This retrospective study reviewed bone specimen records in the cancer registry at Kilimanjaro Christian Medical Centre (KCMC) in Tanzania, for the period from 1 January 1998-31 December 2012. Patient information for corresponding cancer registry records was traced from hospital files and x-ray reports. Data were analysed using a mixed quantitative and qualitative approach.

Results: Two hundred twenty-five malignant bone tumours were recorded at KCMC Cancer Registry over a period of 14 years. Seventy-five with adequate records were analysed. Fortyseven patients (62.7%) were male. Mean age was 34.1 (standard deviation 20) years. The femur was affected in 26 cases (34.7%). Osteosarcoma (22 cases; 29.3%) was the most common malignant bone tumour. Clinicians correctly preliminarily diagnosed multiple myeloma, osteosarcoma, and ameloblastoma, but had inexperience with carcinomas and other types of sarcomas. Chronic osteomyelitis and metastatic lesions were mentioned frequently by radiologists as the diagnosis of some malignant bone tumours that turned out to be carcinomas or sarcomas on histology.

Conclusions: Clinician and radiologist training of other types of malignant bone tumours other than multiple myeloma, osteosarcoma, and ameloblastoma is required. An Orthopaedic Biopsy Form (OBF) was developed to address high loss to follow-up (66.7%).