Lack of increased risk for extracranial, nonleukemic neoplasms in recipients of recombinant deoxyribonucleic acid growth hormone.

This report describes cases of new extracranial nonleukemic neoplasms in recombinant human GH (rhGH) recipients. The data are largely from the National Cooperative Growth Study (NCGS), with over 51,000 patient-years at risk from 12,209 patients treated with Protropin rhGH. In addition to case reports of extracranial tumors from the NCGS enrollees, there have been reports from non-NCGS patients. Ten cases of new extracranial neoplasms have been reported from this total study population, and there have been eight cases whose second neoplasms were extracranial in nature. For the new cases, the number of observed cases is compared with the number of expected cases, as derived from incidence rates published by the National Cancer Institute's SEER (Surveillance, Epidemiology, and End Results) Program. The standard morbidity ratio (SMR), defined as the number of observed cases/expected cases, is calculated for males and females separately, with further subgroup analysis based upon age. For the NCGS population, the SMRs were not statistically distinguishable from unity (i.e. 1). When the number of non-NCGS Protropin patients is estimated and SMRs are calculated for the total Protropin-treated group, the SMRs remain statistically indistinguishable from one. At present, these data suggest that rhGH does not increase the risk for developing nonleukemic extracranial neoplasms. Because a small number of additional cases could significantly alter the SMR calculations, meticulous reporting and continued surveillance must continue.