Second primary cancer due to radiotherapy and chemotherapy.

Cancer patients are treated successfully with chemotherapy, radiotherapy, or a combination of both. However, many agents used in cancer chemotherapy as well as ionizing radiation are known carcinogens. The long survival of cancer patients treated successfully for their primary cancer made possible the observations of late effects of radiotherapy and chemotherapy and, in particular, the occurrence of second primary cancers. In this report we review the cases of five patients with second primary malignancies and wish to emphasize the importance of a thorough follow-up of patients treated successfully for and possibly cured of a primary cancer.