1 Department of Pediatrics, Yale School of Medicine, 333 Cedar Street, New Heaven, Connecticut 06511
The quantitative data supplied by Drs. Oleinick and Glass are greatly appreciated. In view of the small size of the study sample reported by Putnam, Moore, and Mitchell,1 it is true that a significant increase in leukemia or lymphoma could still exist undetected. Infectious lymphocytosis has often been characterized by an extra-ordinary proliferation of cells to levels tenfold or more above normal. Such a phenomenon might be followed in later years by increased risk of malignancy 130 times normal or above.