1. Skeletal metastasis resulting from a carcinoma may occur without any clinical evidence of a primary lesion.
2. The prostate is the most common source of skeletal metastasis; the breast, second; the kidney, third, while the stomach, lung, thyroid and other organs are involved less frequently and in the order given.
3. The size of the primary lesion is no index of the probability of metastasis.
4. Metastasis to bone may occur many years following the primary operation, and in the present series of cases of breast cancer skeletal metastasis was observed as late as eighteen and twenty-five hundredths years postoperatively.
5. Irradiation of the osseous lesions relieves pain and prolongs the life of the patient.