Late effects of treatment of cancer in infancy.

Eighty-six children were diagnosed with cancer in infancy, followed for at lest 5 years, and assessed for late effects of disease and therapy. One child subsequently died from respiratory failure and 3 died from second primary cancers. Another patient survived second primary cancers of the skin. The high frequency of new cancers (4 observed, 0.09 expected) was attributable to host susceptibility factors and treatment effects. Kyphoscoliosis was diagnosed in 44 patients, 40 of whom had received radiotherapy to the spine. Other patients had neurologic deficits, pulmonary fibrosis, hypoplastic breasts, bowel adhesions, thyroid nodules, musculoskeletal defects, and liver fibrosis associated with tumor therapy. Sequelae of cancer were more common after treatment in infancy than in later childhood. Improved treatments and knowledge of natural history can reduce adverse effects of therapy.