Origin, pattern of bone metastasis and need for surgery in patients with Metastatic bone disease treated at tertiary hospital in Northern Tanzania. A hospital based cross sectional study

Bones are the third most common sites for cancer metastasis after lung and liver. Bone metastasis cause skeletal complications (SREs) that affect the quality of life of patients with bone metastasis. Management of these patients depend on the primary tumor and pattern of bone metastasis. The aim of this study was to describe the origin, distribution pattern of bone metastases, common SREs and proportion of patients with bone metastasis that need surgery. A cross sectional study was conducted among cancer patients with Metastatic bone disease attending KCMC Hospital from November 2022 to April 2023. Data was collected from patients files, histopathology and radiology reports by a structured extraction sheet. VAS, SINS and Mirels scores was used to document pain severity, spinal instability and fracture risk respectively. The ASIA impairment scale was used for documenting neurological deficits in patients with spine metastasis. Data was entered and analyzed in SPSS version 25.0 A total of 72 participants were enrolled. Their mean age was 69 {+/-} 11 years and (75%) were male. Prostate cancer (65.3%) was the leading cause of metastatic bone disease followed by breast cancer (18.1%). Most of patients with MBD have multiple lesions (91.7%) involving multiple sites but the spine (93.1%) was the mostly affected site. Osteoblastic lesions were the predominant radiological type by 59.7% followed by osteolytic lesions which accounted for 23.6% of the study participants. 30.6% had pathological fractures and half of these occurred in patients with osteolytics lesions. 36.1% of the study participants had an indication for surgical treatment of the bone metastasis. Most of MBD originate from Prostate and Breast cancer giving multiple lesions involving multiple sites but the spine remains to be the most affected site. Even though about a third of the patients had SREs that needed surgical intervention but few are expected to be operated considering the prognosis. This calls for more emphasis on prevention of SREs and use of appropriate less invasive therapies to prevent progression of the disease.