Objectives: The aim of this study was to explore the distribution features of metastatic bony lesions in prostate cancer.
Materials and methods: Bone scans with 99mTc-methylene diphosphonate were performed in 144 patients with pathologically proven prostate cancer, and distribution regularity of metastatic bony lesions was analyzed retrospectively.
Results: A total of 2000 lesions of bone metastasis were detected in 102 patients, 28.9% of which were distributed in the ribs, 14.8% in thoracic vertebrae, 13.8% in the ilium, and 8.0% in the lumbar vertebrae. The distribution of metastatic bony lesions was correlated with the total number of lesions. The proportion of metastatic lesions of vertebrae and pelvis was up to 84.5% (49/58) in fewer bone metastases. The proportion gradually decreased with an increase in the total number of lesions, but the proportion of the bony lesions, except for the vertebrae and pelvis, gradually increased with an increase in the total number of lesions. Ninety-nine percent (903/912) of metastatic bony lesions, except for the vertebrae and pelvis, coexisted with metastasis of vertebrae or pelvis, whereas only 1.0% (9/912) of those were detected in no metastasis of the vertebrae and pelvis; their difference was significant (χ2=876.4, P=0.000). About 98.8% (571/578) of metastatic costal lesions coexisted with vertebrae metastasis, but only 1.2% (7/578) of these were detected in no metastasis of vertebrae; their difference was significant (χ2=550.3, P=0.000). The difference between left body and right body was not significant (χ=1.3, P=0.249).
Conclusion: Metastatic bony lesions of prostate cancer are located mainly in the vertebrae and pelvis in the early stage. The distribution of metastatic bony lesions is not only characterized by spreading to left body and right body randomly, but also presents the tendency of developing with orderliness to a certain extent in the whole body.