ABSTRACT
Introduction@#Bone scan is the modality of choice for evaluation of bone metases in asymptomatic patients primary malignancy. The distribution and pattern of bone metases in prostate, breast, and lung malignancies are investigated using bone scan results. This could aid future interpretation of bone scans and narrow down the differential diagnoses by establishing the likely regional location of metastatic bone disease in commonly encountered malignancies. @*Materials and methods@#Chart review of a total of 411 patients with histologically proven malignant disease, who underwent bone scan in the Division of Nuclear Medicine of the Philippine Heart Center for the first time from October 2013 to October 2016, was conducted. @*Results@#Out of 411 patients, 149 had metastatic bone disease; 42 (28.2%) had lung cancer, 26 (17.4%) had prostate cancer, 60 (40.3%) had breast cancer, while the remaining 21 (14.1%) had other primary malignancies. Majority of the lessions were multiple and were found in the ribs, vertebrae and pelvic bones for lung cancer; ribs, lower thoraric and lumbar vertebrae, and pelvic bones for prostate and breast cancer. @*Conclusion@#There was no scintigraphic pattern attributable to a particular malignancy but rather, sites of predilection were observed in this study. The top 3 regions of distribution of bone metasis were as follows: for lung cancer, 1. ribs, 2. vertebrae, 3. pelvic bones; for prostate cancer,1. lower thoracic and lumbar vertebrae, 2. pelvic bones; 3. ribs; for breast cancer, 1. lower thoracic and lumbar vertebrae, 2. ribs, 3. pelvic bones. Involvement of the long bones wasw highest among lung and prostate cancers; whereas metasis to the sternum was most commonly seen in breast cancer.