1 Bone Cancer
Risk Factors:
Bone cancers account for 0.5% of all malignant neoplasms in the human. There are three main types of bone cancer. Osteosarcoma, which arises most often in the growing ends of long bones; chondrosarcoma, which develops in the metaphysis; and Ewing’s sarcoma, which according to recent evidence may arise from primitive nervous tissue in the bones of the axial skeleton. Several additional types of bone cancer are much less common, and include chordoma, fibrous histiocytoma, and fibrosarcoma.
Osteosarcoma has a bi-modal distribution with peaks in adolescence and late in life. Early studies of incidence and mortality indicate that higher and sustained increased prevalence in young males might be related to the adolescent growth spurt. The adolescent peak for osteosarcoma appears to be related to the pubertal growth spurt, and the rising incidence after middle age has been linked to Paget’s disease.
A role for genetic susceptibility is suggested from the association of osteosarcoma with retinoblastoma and the Li-Fraumeni syndrome; and from the near-absence of Ewing’s sarcoma in Blacks and Asians. Further research is needed in this area.
Prevention:
No primary prevention measures are presently available. Bone cancer is rare in B.C., and no screening maneuvers have been identified to date to reduce mortality from the disease.
References:
- Miller RW, Boice JD Jr., Curtis RE, Bone cancer. In Schottenfeld D, Fraumeni JF Jr.. (Eds) Cancer Epidemiology and Prevention 2nd Ed. 1996. Oxford University Press, Oxford. Pp971-983.
2 Soft Tissue Sarcomas
Risk Factors:
Cancers of soft tissue account for about 1% of all malignant neoplasms and for about 1% of all cancer deaths. Generally speaking, the statistics in Canada indicate an upward trend in both incidence and mortality of soft tissue sarcomas.
Ionizing radiation at high doses is known to produce a variety of sarcomas, but accounts for only a small fraction of the cases. Thorotrast, vinyl chloride, inorganic arsenic, and androgenic steroids can induce hepatic angiosarcomas, and recent studies have linked soft tissue sarcomas with occupational exposures to herbicides, mainly phenoxyacetic acids and chlorophenols.
An excess of soft tissue sarcomas has been reported in patients receiving therapeutic immunosuppression for renal transplantation and other conditions, although risk is not as high as for non-Hodgkin’s lymphoma.
Prevention:
No recommendations regarding primary prevention can be made at this time. No screening maneuvers are available for soft tissue sarcomas.
References:
- Zahm SH, Tucker MA, Fraumeni JF Jr.. Soft tissue sarcomas. In: Schottenfeld D, Fraumeni JF Jr. (Eds) Cancer Epidemiology and Prevention 2nd Ed. 1996. Oxford University Press, Oxford, Pp984-999.