Comparison of distribution characteristics of metastatic bone lesions between breast and prostate carcinomas.

The purpose of the present study was to investigate the distribution characteristics of bone metastases in breast and prostate carcinomas. Bone scintigraphies were performed in 504 cancer patients. We studied the correlation between the distribution and total number of metastatic bone lesions, and compared the distribution of metastatic bone lesions between breast and prostate carcinomas. In the early stage, the distribution in the thoracic vertebrae, lumbar vertebrae and pelvis of the metastatic lesions of the prostate carcinoma (81.0%, 47/58) was significantly higher than that of the breast carcinoma (41.7%, 63/151; χ(2)=27.6, P=0.000). The distribution of the lesions in the thoracic skeleton in the cases of the breast carcinoma (65.6%, 99/151) was significantly higher than that of the prostate carcinoma (27.6%, 16/58; χ(2)=24.8, P=0.000); however, the distributions in the advanced cases were not markedly different. The differences in the proportions of the metastatic lesions in the lumbar vertebrae (χ(2)=56.1, P=0.000) and ribs (χ(2)=39.1, P=0.000) in the cases of the prostate carcinoma, and in the sternum (χ(2)=31.2, P=0.000), skull (χ(2)=26.5, P=0.000) and femur (χ(2)=13.6, P=0.001) in the cases of the breast carcinoma were significant. Between the breast and prostate carcinomas, the differences in the proportions of the metastatic lesions of certain bones were also significant. In cases with few bone metastases, the proportion of sternum metastases of patients with breast carcinoma (17.9%) was significantly higher than that of patients with prostate carcinoma (1.7%; χ(2)=12.7, P=0.000); the proportion of metastases in the lumbar vertebrae of prostate carcinoma (39.7%) was significantly higher than that of breast carcinoma (13.9%; χ(2)=15.4, P=0.000); the proportion of rib metastases of breast carcinoma (27.2%) was significantly higher than that of prostate carcinoma (8.6%; χ(2)=9.6, P=0.002). In cases with extensive bone metastases, the proportions of metastatic lesions in the sternum and lumbar vertebrae in breast and prostate carcinomas were not significantly different (P>0.05). In conclusion, the distribution of bone metastases is correlated with the total number of metastatic bone lesions in breast and prostate carcinoma patients, and has different characteristics in different lesions.