Giant-cell pneumonia and lung tumorlets in a leukemic four-year-old child

The authors report the case of a 4-year-old child whose death resulted from acute lymphoblastic leukemia (ALL) and giant-cell pneumonia. Typical lung tumorlets were occasionally observed. On electron microscopic study it was possible to demonstrate a large number of neurosecretory granules in the tumorlet cells, identical to those present in Kulchitsky's cells. These studies suggest the occurrence of an abnormal immune process.