Radiation-induced malignant tumors of bone in patients with Hodgkin's disease

Sixteen cases of radiogenic malignant bone tumors which developed in patients 4 to 31 y after they had received radiation therapy for Hodgkin's disease are compared with 70 similar cases occurring after radiation exposure for other causes. No significant differences in age at irradiation, latent period, histology of tumors or radiographic characteristics were found between the Hodgkin's cases and those of the comparison series. Fourteen of the 16 tumors in Hodgkin's patients, or 87%, were diagnosed in the 15-y period between 1971 and 1985 in contrast to only 34% of the larger non-Hodgkin's series. This difference appears significant and is associated with a doubling of the proportion of Hodgkin's patients who are now living past the minimum latent period for such tumors. The median dose in the Hodgkin's patients, 4000 cGy, is less than the 5100-cGy median in the other patients, and the range and protraction of the total doses are much less. In Hodgkin's patients who have received total nodal irradiation, the volume of osseous tissue which is exposed may reach 25% of the total in the body. This is much greater than in most other treatment plans. Six of the Hodgkin's patients received chemotherapy within a few months of irradiation; only three of 70 non-Hodgkin's patients did so. All of the last factors may have modified the risk of radiation carcinogenesis in the Hodgkin's patients but the data are not yet adequate for quantitation of the effect.