Low- and high-risk non-T and non-B and T-cell acute lymphoid leukemia (ALL) in childhood: different duration of remission and survival.

In a prospective, nonrandomized trial clinical (initial WBC and chest film) and immunological (surface immunoglobulin and rosetting with pretreated sheep red blood cells) criteria were used to stratify 69 children with previously untreated acute lymphoid leukemia (ALL). Forty of 61 evaluable patients had low-risk ALL (initial WBC less than or equal to 20,000/mm3, no mediastinal mass) and were treated less intensively. Twenty-one of 61 patients had high-risk ALL (initial WBC greater than 20,000/mm3 and/or mediastinal mass) and were treated more intensively. Of the high-risk patients 15 had non-T non-B and 6 T ALL. Sixty of 61 patients went into complete remission. After a median observation period of 27 months, 32 of 40 low-risk, 7 of 14 high-risk non-T non-B, and none of 6 high-risk T ALL patients were in continuous first remission. Thirty-six of 40 low-risk, 9 of 15 high-risk non-T non-B, and none of 6 T ALL patients were alive. Despite more intensive treatment, the duration of remission and the survival were significantly shorter in the high-risk than in the low-risk patients. Among the high-risk ALL, non-T non-B ALL did better than T ALL.