title: Not all second cancers are secondary. In regard to Mourad et al: "Radiation-induced sarcoma following radiation prophylaxis of heterotopic ossification".
authors.affiliation: NIU Neutron Therapy Facility, Fermilab, PO Box 500, Mail Stop 301, Batavia, IL 60510, USA. Electronic address: jameswelsh@charter.net.
authors.forename: James S
authors.initials: JS
authors.lastname: Welsh